DNA analysis for predisposition to cancer. What I learned about myself from the genetic test

The introduction of molecular genetic analyzes into clinical practice has allowed medicine to achieve great success in the diagnosis and treatment of oncology. Modern methods create additional opportunities for making an accurate diagnosis and determining predisposition, prognosis, as well as for an individual approach to cancer therapy based on the genetic analysis of tumor cells.

Cancer tests are performed in the following situations:

assessment of predisposition to hereditary forms of malignant neoplasms;

clarification of the diagnosis in doubtful cases;

determining the effectiveness of chemotherapy.

These types of studies are performed on modern equipment at an affordable cost in the Allel laboratory in Moscow.

Predisposition to hereditary cancer

As a result of the test, mutations in genes that indicate a hereditary predisposition to oncology can be detected. Such a study is mandatory if first-degree relatives have or had a disease at a young age (usually before 40 years). Often there are 3 hereditary forms of oncology:

mammary cancer;

ovarian cancer;

colon cancer.

These diseases have characteristic genetic damage that indicates a predisposition. However, there is more and more data on the role of heredity in the development of other types of oncology (stomach, lung, prostate, etc.).

Identification of predisposition in this case allows you to put the patient on dispensary observation and promptly remove the tumor in the early stages if it occurs.

Selection of effective chemotherapy regimens

Genetic tests are also important for advanced cancers. In this case, by examining the DNA of tumor cells, one can choose an effective therapy, as well as predict its effectiveness. For example, if there are a large number of copies of the Her-2 / neu gene in the tumor tissue of breast or stomach cancer, therapy with Trastuzumab is indicated, and Cetuximab has an effect only in the absence of mutations in the K-ras and N-ras genes in cells colon cancer.

In this case, genetic analysis allows you to determine the effective type of therapy for the disease.

Establishing diagnosis

Molecular tests in oncology are used to make a correct diagnosis. Some malignant tumors have characteristic genetic damage.

Deciphering genetic analysis

The results contain information about the state of the patient's DNA, which may indicate predisposition to certain diseases or sensitivity to certain types of treatment. As a rule, in the description of the genetic analysis, the mutations for which the test was performed are indicated, and their significance in a particular clinical situation is determined by the doctor. It is extremely important that the attending physician has all the necessary information about the possibilities of molecular diagnostics in oncology.

How is genetic analysis performed?

In order to make a genetic analysis for the presence of a predisposition to hereditary forms of cancer, the patient's whole blood is needed. There are no contraindications to the test, special preparation is not required.

To perform a genetic analysis of an already existing tumor, the tumor cells themselves will be required. It should be noted that diagnostic methods for detecting circulating DNA of cancer cells in the blood are already being developed.

There are various methods for detecting mutations in genes. Most commonly used:

FISH analysis - fluorescent in situ hybridization. Allows you to analyze large sections of DNA (translocations, amplifications, duplications, inversions) of chromosomes.

Polymerase chain reaction (PCR). It helps to study only small fragments of DNA, but it has a low price and high accuracy.

Sequencing. The method allows you to completely decipher the sequence of genes and find all existing mutations.

The test for hereditary cancer predisposition is passed once, as the DNA sequence does not change. Only individual cells can mutate.

In the presence of a tumor in a patient, its DNA can be examined several times (for example, before and after chemotherapy), since tumor cells have a high ability to mutate.

The accuracy of DNA genetic analysis for oncology in the Allel laboratory in Moscow is 99-100%. We use modern methods that have proven their effectiveness in scientific research, at a relatively low cost of research.

Indications for genetic analysis

According to various data, the share of hereditary forms of cancer accounts for about 5-7% of all cases of malignant neoplasms. The main indication for determining predisposition is the presence of oncology in first-degree relatives at a young age.

The indication for the study of DNA of already existing tumor cells is the very presence of a tumor. Before genetic testing is carried out, a physician should be consulted to determine what tests are needed and how they may affect therapeutic measures and prognosis.

Modern methods of genetic analysis can identify predisposition, as well as improve the effectiveness of cancer prevention and treatment. Today, a personalized approach is used in every specialized clinic in Moscow, which allows you to select exactly those treatment regimens that will have the maximum possible effect on a particular patient. This reduces the price and increases the effectiveness of the treatment of the disease.

Head of
"Oncogenetics"

Zhusina
Julia Gennadievna

Graduated from the Pediatric Faculty of the Voronezh State Medical University. N.N. Burdenko in 2014.

2015 - internship in therapy on the basis of the Department of Faculty Therapy of the Voronezh State Medical University. N.N. Burdenko.

2015 - certification course in the specialty "Hematology" on the basis of the Hematological Research Center in Moscow.

2015-2016 – therapist of the VGKBSMP No. 1.

2016 - the topic of the dissertation for the degree of candidate of medical sciences "study of the clinical course of the disease and prognosis in patients with chronic obstructive pulmonary disease with anemic syndrome" was approved. Co-author of more than 10 publications. Participant of scientific and practical conferences on genetics and oncology.

2017 - advanced training course on the topic: "interpretation of the results of genetic studies in patients with hereditary diseases."

Since 2017 residency in the specialty "Genetics" on the basis of RMANPE.

Head of
"Genetics"

Kanivets
Ilya Vyacheslavovich

Kanivets Ilya Vyacheslavovich, geneticist, candidate of medical sciences, head of the genetics department of the medical genetic center Genomed. Assistant of the Department of Medical Genetics of the Russian Medical Academy of Continuous Professional Education.

He graduated from the Faculty of Medicine of the Moscow State University of Medicine and Dentistry in 2009, and in 2011 he completed residency in the specialty "Genetics" at the Department of Medical Genetics of the same university. In 2017 he defended his thesis for the degree of candidate of medical sciences on the topic: Molecular diagnosis of copy number variations of DNA segments (CNVs) in children with congenital malformations, phenotype anomalies and/or mental retardation using SNP high-density oligonucleotide microarrays»

From 2011-2017 he worked as a geneticist at the Children's Clinical Hospital. N.F. Filatov, scientific advisory department of the Federal State Budgetary Scientific Institution "Medical Genetic Research Center". From 2014 to the present, he has been in charge of the genetics department of the MHC Genomed.

Main activities: diagnosis and management of patients with hereditary diseases and congenital malformations, epilepsy, medical genetic counseling of families in which a child was born with a hereditary pathology or malformations, prenatal diagnostics. During the consultation, an analysis of clinical data and genealogy is carried out to determine the clinical hypothesis and the required amount of genetic testing. Based on the results of the survey, the data are interpreted and the information received is explained to the consultants.

He is one of the founders of the School of Genetics project. Regularly makes presentations at conferences. He lectures for geneticists, neurologists and obstetricians-gynecologists, as well as for parents of patients with hereditary diseases. He is the author and co-author of more than 20 articles and reviews in Russian and foreign journals.

The area of professional interests is the introduction of modern genome-wide studies into clinical practice, the interpretation of their results.

Reception time: Wed, Fri 16-19

Head of
"Neurology"

Sharkov
Artem Alekseevich

Sharkov Artyom Alekseevich– neurologist, epileptologist

In 2012, he studied under the international program “Oriental medicine” at Daegu Haanu University in South Korea.

Since 2012 - participation in the organization of the database and algorithm for the interpretation of xGenCloud genetic tests (http://www.xgencloud.com/, Project Manager - Igor Ugarov)

In 2013 he graduated from the Pediatric Faculty of the Russian National Research Medical University named after N.I. Pirogov.

From 2013 to 2015 he studied in clinical residency in neurology at the Federal State Budget Scientific Institution "Scientific Center of Neurology".

Since 2015, he has been working as a neurologist, researcher at the Scientific Research Clinical Institute of Pediatrics named after Academician Yu.E. Veltishchev GBOU VPO RNIMU them. N.I. Pirogov. He also works as a neurologist and a doctor in the laboratory of video-EEG monitoring in the clinics of the Center for Epileptology and Neurology named after A.I. A.A. Ghazaryan” and “Epilepsy Center”.

In 2015, he studied in Italy at the school "2nd International Residential Course on Drug Resistant Epilepsies, ILAE, 2015".

In 2015, advanced training - "Clinical and molecular genetics for practicing physicians", RCCH, RUSNANO.

In 2016, advanced training - "Fundamentals of Molecular Genetics" under the guidance of bioinformatics, Ph.D. Konovalova F.A.

Since 2016 - the head of the neurological direction of the laboratory "Genomed".

In 2016, he studied in Italy at the school "San Servolo international advanced course: Brain Exploration and Epilepsy Surger, ILAE, 2016".

In 2016, advanced training - "Innovative genetic technologies for doctors", "Institute of Laboratory Medicine".

In 2017 - the school "NGS in Medical Genetics 2017", Moscow State Scientific Center

Currently, he is conducting scientific research in the field of epilepsy genetics under the guidance of Professor, MD. Belousova E.D. and professor, d.m.s. Dadali E.L.

The topic of the dissertation for the degree of Candidate of Medical Sciences "Clinical and genetic characteristics of monogenic variants of early epileptic encephalopathies" was approved.

The main areas of activity are the diagnosis and treatment of epilepsy in children and adults. Narrow specialization - surgical treatment of epilepsy, genetics of epilepsy. Neurogenetics.

Scientific publications

Sharkov A., Sharkova I., Golovteev A., Ugarov I. "Optimization of differential diagnostics and interpretation of results of genetic testing by the XGenCloud expert system in some forms of epilepsy". Medical Genetics, No. 4, 2015, p. 41.
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Sharkov A.A., Vorobyov A.N., Troitsky A.A., Savkina I.S., Dorofeeva M.Yu., Melikyan A.G., Golovteev A.L. "Surgery for epilepsy in multifocal brain lesions in children with tuberous sclerosis." Abstracts of the XIV Russian Congress "INNOVATIVE TECHNOLOGIES IN PEDIATRICS AND PEDIATRIC SURGERY". Russian Bulletin of Perinatology and Pediatrics, 4, 2015. - p.226-227.
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Dadali E.L., Belousova E.D., Sharkov A.A. "Molecular genetic approaches to the diagnosis of monogenic idiopathic and symptomatic epilepsy". Abstract of the XIV Russian Congress "INNOVATIVE TECHNOLOGIES IN PEDIATRICS AND PEDIATRIC SURGERY". Russian Bulletin of Perinatology and Pediatrics, 4, 2015. - p.221.
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Sharkov A.A., Dadali E.L., Sharkova I.V. "A rare variant of type 2 early epileptic encephalopathy caused by mutations in the CDKL5 gene in a male patient." Conference "Epileptology in the system of neurosciences". Collection of conference materials: / Edited by: prof. Neznanova N.G., prof. Mikhailova V.A. St. Petersburg: 2015. - p. 210-212.
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Dadali E.L., Sharkov A.A., Kanivets I.V., Gundorova P., Fominykh V.V., Sharkova I.V. Troitsky A.A., Golovteev A.L., Polyakov A.V. A new allelic variant of type 3 myoclonus epilepsy caused by mutations in the KCTD7 gene // Medical genetics.-2015.- v.14.-№9.- p.44-47
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Dadali E.L., Sharkova I.V., Sharkov A.A., Akimova I.A. "Clinical and genetic features and modern methods of diagnosing hereditary epilepsy". Collection of materials "Molecular biological technologies in medical practice" / Ed. corresponding member RANEN A.B. Maslennikova.- Issue. 24.- Novosibirsk: Academizdat, 2016.- 262: p. 52-63
*
Belousova E.D., Dorofeeva M.Yu., Sharkov A.A. Epilepsy in tuberous sclerosis. In "Brain Diseases, Medical and Social Aspects" edited by Gusev E.I., Gekht A.B., Moscow; 2016; pp.391-399
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Dadali E.L., Sharkov A.A., Sharkova I.V., Kanivets I.V., Konovalov F.A., Akimova I.A. Hereditary diseases and syndromes accompanied by febrile convulsions: clinical and genetic characteristics and diagnostic methods. //Russian Journal of Children's Neurology.- T. 11.- No. 2, p. 33-41. doi: 10.17650/ 2073-8803-2016-11-2-33-41
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Sharkov A.A., Konovalov F.A., Sharkova I.V., Belousova E.D., Dadali E.L. Molecular genetic approaches to the diagnosis of epileptic encephalopathies. Collection of abstracts "VI BALTIC CONGRESS ON CHILDREN'S NEUROLOGY" / Edited by Professor Guzeva V.I. St. Petersburg, 2016, p. 391
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Hemispherotomy in drug-resistant epilepsy in children with bilateral brain damage Zubkova N.S., Altunina G.E., Zemlyansky M.Yu., Troitsky A.A., Sharkov A.A., Golovteev A.L. Collection of abstracts "VI BALTIC CONGRESS ON CHILDREN'S NEUROLOGY" / Edited by Professor Guzeva V.I. St. Petersburg, 2016, p. 157.
*
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Article: Genetics and differentiated treatment of early epileptic encephalopathies. A.A. Sharkov*, I.V. Sharkova, E.D. Belousova, E.L. Dadali. Journal of Neurology and Psychiatry, 9, 2016; Issue. 2doi:10.17116/jnevro20161169267-73
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Golovteev A.L., Sharkov A.A., Troitsky A.A., Altunina G.E., Zemlyansky M.Yu., Kopachev D.N., Dorofeeva M.Yu. "Surgical treatment of epilepsy in tuberous sclerosis" edited by Dorofeeva M.Yu., Moscow; 2017; p.274
*
New international classifications of epilepsy and epileptic seizures of the International League against epilepsy. Journal of Neurology and Psychiatry. C.C. Korsakov. 2017. V. 117. No. 7. S. 99-106

Head of
"Prenatal Diagnosis"

Kyiv
Yulia Kirillovna

In 2011 she graduated from the Moscow State Medical and Dental University. A.I. Evdokimova with a degree in General Medicine Studied in residency at the Department of Medical Genetics of the same university with a degree in Genetics

In 2015, she completed an internship in Obstetrics and Gynecology at the Medical Institute for Postgraduate Medical Education of the Federal State Budgetary Educational Institution of Higher Professional Education "MGUPP"

Since 2013, he has been conducting a consultative appointment at the Center for Family Planning and Reproduction, DZM

Since 2017, he has been the head of the Prenatal Diagnostics department of the Genomed laboratory

Regularly makes presentations at conferences and seminars. Reads lectures for doctors of various specialties in the field of reproduction and prenatal diagnostics

Conducts medical genetic counseling for pregnant women on prenatal diagnostics in order to prevent the birth of children with congenital malformations, as well as families with presumably hereditary or congenital pathologies. Conducts interpretation of the obtained results of DNA diagnostics.

SPECIALISTS

Latypov
Artur Shamilevich

Latypov Artur Shamilevich – doctor geneticist of the highest qualification category.

After graduating from the medical faculty of the Kazan State Medical Institute in 1976, for many years he worked first as a doctor in the office of medical genetics, then as head of the medical genetic center of the Republican Hospital of Tatarstan, chief specialist of the Ministry of Health of the Republic of Tatarstan, teacher at the departments of Kazan Medical University.

Author of more than 20 scientific papers on the problems of reproductive and biochemical genetics, participant in many domestic and international congresses and conferences on the problems of medical genetics. He introduced methods of mass screening of pregnant women and newborns for hereditary diseases into the practical work of the center, performed thousands of invasive procedures for suspected hereditary diseases of the fetus at different stages of pregnancy.

Since 2012, she has been working at the Department of Medical Genetics with a course in prenatal diagnostics at the Russian Academy of Postgraduate Education.

Research interests – metabolic diseases in children, prenatal diagnostics.

Reception time: Wed 12-15, Sat 10-14

Doctors are admitted by appointment.

Geneticist

Gabelko
Denis Igorevich

In 2009 he graduated from the medical faculty of KSMU named after. S. V. Kurashova (specialty "Medicine").

Internship at the St. Petersburg Medical Academy of Postgraduate Education of the Federal Agency for Health and Social Development (specialty "Genetics").

Internship in Therapy. Primary retraining in the specialty "Ultrasound diagnostics". Since 2016, he has been an employee of the Department of the Department of Fundamental Foundations of Clinical Medicine of the Institute of Fundamental Medicine and Biology.

Area of professional interests: prenatal diagnosis, the use of modern screening and diagnostic methods to identify the genetic pathology of the fetus. Determining the risk of recurrence of hereditary diseases in the family.

Participant of scientific and practical conferences on genetics and obstetrics and gynecology.

Work experience 5 years.

Consultation by appointment

Doctors are admitted by appointment.

Geneticist

Grishina
Christina Alexandrovna

In 2015 she graduated from the Moscow State Medical and Dental University with a degree in General Medicine. In the same year, she entered residency in the specialty 30.08.30 "Genetics" at the Federal State Budgetary Scientific Institution "Medical Genetic Research Center".
She was hired in the Laboratory of Molecular Genetics of Complexly Inherited Diseases (Head - Doctor of Biological Sciences Karpukhin A.V.) in March 2015 as a research laboratory assistant. Since September 2015, she has been transferred to the position of a researcher. He is the author and co-author of more than 10 articles and abstracts on clinical genetics, oncogenetics and molecular oncology in Russian and foreign journals. Regular participant of conferences on medical genetics.

Area of scientific and practical interests: medical genetic counseling of patients with hereditary syndromic and multifactorial pathology.

Consultation with a geneticist allows you to answer the following questions:

Are the child's symptoms signs of a hereditary disease? what research is needed to identify the cause determining an accurate forecast recommendations for conducting and evaluating the results of prenatal diagnosis everything you need to know about family planning IVF planning consultation field and online consultations

took part in the scientific-practical school "Innovative genetic technologies for doctors: application in clinical practice", the conference of the European Society of Human Genetics (ESHG) and other conferences dedicated to human genetics.

Conducts medical genetic counseling for families with presumably hereditary or congenital pathologies, including monogenic diseases and chromosomal abnormalities, determines the indications for laboratory genetic studies, interprets the results of DNA diagnostics. Advises pregnant women on prenatal diagnostics in order to prevent the birth of children with congenital malformations.

Geneticist, obstetrician-gynecologist, candidate of medical sciences

Kudryavtseva
Elena Vladimirovna

Geneticist, obstetrician-gynecologist, candidate of medical sciences.

Specialist in the field of reproductive counseling and hereditary pathology.

Graduated from the Ural State Medical Academy in 2005.

Residency in Obstetrics and Gynecology

Internship in the specialty "Genetics"

Professional retraining in the specialty "Ultrasound diagnostics"

Activities:

Infertility and miscarriage

She is a graduate of the Nizhny Novgorod State Medical Academy, Faculty of Medicine (specialty "Medicine"). She graduated from the clinical internship of the FBGNU "MGNTS" with a degree in "Genetics". In 2014, she completed an internship at the clinic of motherhood and childhood (IRCCS materno infantile Burlo Garofolo, Trieste, Italy).

Since 2016, she has been working as a consultant doctor at Genomed LLC.

Regularly participates in scientific and practical conferences on genetics.

Main activities: Consulting on clinical and laboratory diagnostics of genetic diseases and interpretation of results. Management of patients and their families with suspected hereditary pathology. Consulting when planning a pregnancy, as well as during pregnancy on prenatal diagnostics in order to prevent the birth of children with congenital pathology.

Cancer kills millions of people every year. Among the causes of death, cancer ranks second after cardiovascular diseases, and in terms of the fear that accompanies it, it is definitely the first. This situation has developed because of the perception that cancer is difficult to diagnose and almost impossible to prevent.

However, every tenth case of cancer is a manifestation of mutations inherent in our genes from birth. Modern science allows them to catch and significantly reduce the risk of disease.

Oncology experts talk about what cancer is, how much genetics influences us, who should get genetic testing as a preventative measure, and how it can help if cancer is already detected.

Ilya Fomintsev

Executive Director of the Foundation for the Prevention of Cancer "Not in vain"

Cancer is essentially a genetic disease. Mutations that cause cancer are either inherited, and then they are in all cells of the body, or appear in some tissue or a specific cell. A person can inherit from their parents a specific mutation in a gene that protects against cancer, or a mutation that itself can lead to cancer.

Non-hereditary mutations occur in initially healthy cells. They occur under the influence of external carcinogenic factors, such as smoking or ultraviolet radiation. Basically, cancer develops in people in adulthood: the process of occurrence and accumulation of mutations can take more than a dozen years. People go through this path much faster if they inherited a breakdown already at birth. Therefore, with tumor syndromes, cancer occurs at a much younger age.

This spring, a wonderful article came out - about random errors that occur during the duplication of DNA molecules and are the main source of oncogenic mutations. In cancers such as prostate cancer, their contribution can be as high as 95%.

Most often, non-hereditary mutations are the cause of cancer: when a person has not inherited any genetic damage, but during life, errors accumulate in the cells, which sooner or later lead to the appearance of a tumor. Further accumulation of these breakdowns already inside the tumor can make it more malignant or lead to the emergence of new properties.

Despite the fact that in most cases, oncological diseases arise due to random mutations, one must take the hereditary factor very seriously. If a person knows about the inherited mutations that he has, he will be able to prevent the development of a particular disease, the risk of which he has a very high risk of developing.

There are tumors with a pronounced hereditary factor. These are, for example, breast cancer and ovarian cancer. Up to 10% of these cancers are associated with mutations in the BRCA1 and BRCA2 genes. The most common type of cancer among our male population - lung cancer - is mostly caused by external factors, and more specifically, by smoking. But if we assume that external causes have disappeared, then the role of heredity would become approximately the same as in breast cancer. That is, in relative terms for lung cancer, hereditary mutations are seen rather weakly, but in absolute numbers it is still quite significant.

In addition, the hereditary component quite significantly manifests itself in cancer of the stomach and pancreas, colorectal cancer, and brain tumors.

Anton Tikhonov

scientific director of the biotechnology company yRisk

Most cancers are caused by a combination of random events at the cellular level and external factors. However, in 5-10% of cases, heredity plays a predetermining role in the occurrence of cancer.

Let's imagine that one of the oncogenic mutations appeared in a germ cell, which was lucky to become a human. Each of the approximately 40 trillion cells of this person (as well as his descendants) will contain a mutation. Therefore, each cell will need to accumulate fewer mutations in order to become cancerous, and the risk of developing a certain type of cancer in a mutation carrier will be significantly higher.

An increased risk of developing cancer is passed from generation to generation along with a mutation and is called hereditary tumor syndrome. Tumor syndromes are quite common - in 2-4% of people, and cause 5-10% of cancer cases.

Thanks to Angelina Jolie, hereditary breast and ovarian cancer, which is caused by mutations in the BRCA1 and BRCA2 genes, has become the most famous tumor syndrome. In women with this syndrome, the risk of developing breast cancer is 45-87%, while the average probability of this disease is much lower - 5.6%. The likelihood of developing cancer in other organs also increases: the ovaries (from 1 to 35%), the pancreas, and in men also the prostate gland.

Almost any cancer has hereditary forms. Tumor syndromes are known to cause cancer of the stomach, intestines, brain, skin, thyroid gland, uterus, and other less common types of tumors.

Knowing that you or your relatives have a hereditary tumor syndrome can be very helpful in reducing the risk of developing cancer, diagnosing it at an early stage, and treating the disease more effectively.

Carrier syndrome can be determined using a genetic test, and the fact that you should take the test will be indicated by the following features of family history.

Several cases of the same type of cancer in the family;

Diseases at an early age for this indication (for most indications - before 50 years);

A single case of a specific type of cancer (eg, ovarian cancer);

Cancer in each of the paired organs;

More than one type of cancer in a relative.

If any of the above apply to your family, you should consult a geneticist who will determine if there is a medical indication for a genetic test. Carriers of hereditary tumor syndromes should undergo thorough cancer screening in order to detect cancer at an early stage. And in some cases, the risk of developing cancer can be significantly reduced with the help of preventive surgery and drug prophylaxis.

Despite the fact that hereditary tumor syndromes are very common, Western national health systems have not yet introduced genetic testing for mutation carriers into widespread practice. Testing is recommended only if there is a specific family history that points to a specific syndrome, and only if the person is known to benefit from testing.

Unfortunately, such a conservative approach misses many carriers of the syndromes: too few people and doctors suspect the existence of hereditary forms of cancer; high risk of the disease is not always manifested in family history; many patients do not know about the diseases of their relatives, even when there is someone to ask.

All this is a manifestation of modern medical ethics, which says that a person should know only what will bring him more harm than good.

Moreover, doctors leave the right to judge what is benefit, what is harm, and how they relate to each other, exclusively to themselves. Medical knowledge is the same interference in worldly life, like pills and operations, and therefore the measure of knowledge should be determined by professionals in bright clothes, otherwise, no matter how something happens.

I, like my colleagues, believe that the right to know about one's own health belongs to people, not to the medical community. We are doing a genetic test for hereditary tumor syndromes so that those who want to know about their risks of developing cancer can exercise this right and take responsibility for their own lives and health.

Vladislav Mileiko

Director of Atlas Oncology Diagnostics

As cancer develops, cells change and lose their original genetic "look" inherited from their parents. Therefore, in order to use the molecular features of cancer for treatment, it is not enough to study only hereditary mutations. Molecular testing of samples obtained from a biopsy or surgery should be performed to find out the weak points of the tumor.

Genome instability allows the tumor to accumulate genetic disorders that may be beneficial to the tumor itself. These include mutations in oncogenes - genes that regulate cell division. Such mutations can greatly increase the activity of proteins, make them insensitive to inhibitory signals, or cause increased production of enzymes. This leads to uncontrolled cell division, and subsequently to metastasis.

what is targeted therapy

Some mutations have known effects: we know exactly how they change the structure of proteins. This makes it possible to develop drug molecules that will act only on tumor cells, and at the same time will not destroy normal cells of the body. Such drugs are called targeted. For modern targeted therapy to work, it is necessary to know what mutations are in the tumor before prescribing treatment.

These mutations can vary even within the same type of cancer. (nosology) in different patients, and even in the same patient's tumor. Therefore, for some drugs, molecular genetic testing is recommended in the instructions for the drug.

Determination of tumor molecular changes (molecular profiling) is an important link in the clinical decision chain, and its importance will only grow with time.

To date, more than 30,000 studies of antitumor therapy are being conducted in the world. According to various sources, up to half of them use molecular biomarkers to enroll patients in a study or for monitoring during treatment.

But what will molecular profiling give the patient? Where is its place in clinical practice today? Although testing is mandatory for a number of drugs, this is just the tip of the iceberg of current molecular testing capabilities. Research results confirm the impact of various mutations on the effectiveness of drugs, and some of them can be found in the recommendations of international clinical communities.

However, at least 50 additional genes and biomarkers are known, the analysis of which may be useful in the choice of drug therapy (Chakravarty et al., JCO PO 2017). Their determination requires the use of modern methods of genetic analysis, such as high throughput sequencing(NGS). Sequencing makes it possible to detect not only common mutations, but also to “read” the complete sequence of clinically significant genes. This allows you to identify all possible genetic changes.

At the stage of analysis of the results, special bioinformatic methods are used that help to identify deviations from the normal genome, even if an important change occurs in a small percentage of cells. The interpretation of the result obtained should be based on the principles of evidence-based medicine, since the expected biological effect is not always confirmed in clinical studies.

Due to the complexity of the process of conducting research and interpreting the results, molecular profiling has not yet become the "gold standard" in clinical oncology. However, there are situations in which this analysis can significantly influence the choice of treatment.

Exhausted possibilities of standard therapy

Unfortunately, even with the right treatment, the disease can progress, and there is not always a choice of alternative therapy within the standards for this cancer. In this case, molecular profiling can reveal "targets" for experimental therapies, including those in clinical trials (eg TAPUR).

the range of potentially significant mutations is wide

Some cancers, such as non-small cell lung cancer or melanoma, are known to have multiple genetic alterations, many of which could be targets for targeted therapy. In this case, molecular profiling can not only expand the choice of possible treatment options, but also help prioritize the choice of drugs.

Rare types of tumors or tumors with an initially poor prognosis

Molecular research in such cases helps to identify a more complete range of possible treatment options at an early stage.

Molecular profiling and treatment personalization require the collaboration of specialists from several fields: molecular biology, bioinformatics and clinical oncology. Therefore, such a study, as a rule, is more expensive than conventional laboratory tests, and only a specialist can determine its value in each case.

Genetic analysis - for money!

if you have no family history of cancer,

it is unlikely that you have a mutated gene;

genetic testing for cancer can be expensive, from a few thousand to tens

thousand rubles;

there is no guarantee that testing will tell if you will get cancer.

Cancer is not usually inherited, but some types - most commonly breast, ovarian, and prostate cancer - are highly gene-dependent and can be inherited.

We all have certain genes that protect us from cancer - they correct DNA damage that occurs naturally when cells divide.

Inherited mutated versions or "variants" of these genes greatly increase the risk of cancer, since the altered genes cannot repair damaged cells, which can eventually form a tumor.

The BRCA1 and BRCA2 genes are examples of genes that increase the chance of cancer if they change. Mutations in the BRCA gene significantly increase a woman's chance of developing breast and ovarian cancer. That is why Angelina Jolie underwent surgery to remove the mammary gland. In men, these genes also increase the likelihood of developing breast and prostate cancer.

Breast cancer genes BRCA1 and BRCA2

If there is a defect (mutation) in one of your BRCA genes, your risk of breast and ovarian cancer is greatly increased.

For example, in women with a mutation in the BRCA1 gene, the probability of developing breast cancer is 60-90%, and ovarian cancer is 40-60%. In other words, out of 100 women with a defect in the BRCA1 gene, urano or later will develop breast cancer, and ovarian cancer.

The defect in the BRCA genes occurs in about one person out of, but Ashkenazi Jews have a much higher risk of this (about one in 40 people has a mutated gene).

But the BRCA genes are not the only genes that increase the risk of cancer. Recently, researchers have identified over 70 new gene variants that are associated with an increased risk of breast, prostate and ovarian cancer. These new gene variants alone only slightly increase the risk of cancer, but when combined, they can significantly increase the likelihood of it.

If you or your partner has a gene that is highly likely to cause cancer, such as a mutated BRCA1 gene, it can be passed on to your children.

How to know if there is a risk of cancer?

If you have a history of cancer in your family and you are concerned that you too may get sick, you may be able to get a genetic test for cancer in a private or public laboratory and they will tell you if you have inherited genes that can cause cancer.

This is called preventive (predictive) genetic testing. “Predictive” means that it is done in advance, and a positive test result indicates that you have a significantly increased risk of cancer. This does not mean that you have cancer or that you will definitely get it.

You may need to be tested for cancer if one of your relatives has already been found to have the mutated gene, or if your family has had multiple cases of cancer.

Genetic testing for cancer: advantages and disadvantages

a positive test result means you can take steps to manage your cancer risk - you can start to live a healthier lifestyle, get regular screenings, take preventive medicines, or have preventive surgery (see "Risk Management" below);
knowing the outcome can help relieve the stress and anxiety that comes from ignorance.

some genetic tests do not give specific results - doctors can determine the variation in a gene, but not know what this can lead to;
a positive result can cause a feeling of constant anxiety - for some people it is easier not to know what threatens them, and they only want to know if they do get cancer.

How is a genetic test done for cancer?

Genetic testing takes place in two stages:

A relative with cancer gets a blood test to determine if they have the cancer-causing gene (this should be done before any healthy relative is tested). The result will be ready in 6-8 weeks.
If your relative's blood test is positive, you may have predictive genetic testing to determine if you have the same mutated gene. Your doctor will refer you to your local genetic testing service for a blood draw (bring a copy of your relative's test results with you). Results will be ready within 10 days after your blood is drawn, but this will most likely not happen during your first appointment.

The Breakthrough Breast Cancer charity explains the importance of these two steps: “Without first analyzing the genes of a diseased relative, testing a healthy person will be like reading a book, looking for a typo in it and not knowing where it is or whether it is there at all.”

Predictive testing is finding a typo in a book when you know what page and line it is on.

A positive result is not a reason to panic

If predictive genetic testing is positive, it means you have a mutated gene that makes you more likely to get cancer.

This does not mean that you will definitely get cancer - your genes only partially influence whether you will get it in the future. Other factors also play a role, such as your medical history, lifestyle, and environment.

If you have one mutated BRCA gene, there is a 50% chance that you will pass it on to your children and a 50% chance that your siblings will also have it.

You may want to discuss the results with members of your family who may also have this gene mutation. The genetics team will discuss with you how a positive or negative test result will affect your life and relationships with your family.

Your doctor may not tell anyone that you have had a genetic test for cancer or disclose the results without your permission.

How to reduce the risk of cancer?

If the test result was positive, there are a number of options for avoiding cancer. Surgery is not the only way out. Ultimately, there are no right or wrong actions - only you can decide what to do.

Regular examination of the mammary glands

If you have a mutation in the BRCA1 or 2 gene, you need to monitor the condition of your breasts and changes in them by regularly feeling your breasts for lumps. Learn what to look out for, including new knots and shape changes.

Breast Cancer Screening

If you're at risk for breast cancer, you can get an annual screening in the form of a mammogram or MRI to monitor your health and diagnose cancer early if it does occur.

The earlier breast cancer is detected, the easier it is to treat. The chances of a complete recovery from breast cancer, especially if it is detected early, are quite high compared to other forms of cancer.

Unfortunately, there is currently no reliable screening method for ovarian or prostate cancer.

Healthy lifestyle

You can reduce your risk of cancer if you lead a healthy lifestyle, such as exercising a lot and eating right.

If you have a mutated BRCA gene, be aware that other factors can make you more likely to get breast cancer. You should avoid:

If the family has had cases of cancer, women are encouraged to breastfeed their children whenever possible.

Medicines (chemoprophylaxis)

According to recent studies, treatment with tamoxifen or raloxifene is recommended for women with an increased risk of breast cancer. These medicines can help reduce your risk.

Preventive surgery

During a prophylactic operation, all tissues (such as the breast or ovaries) in which cancerous growths can appear are removed. People with a defective BRCA gene should consider prophylactic mastectomy (removal of all breast tissue).

In women who have undergone prophylactic mastectomy, the risk of developing breast cancer for the rest of their lives will not exceed 5%, which is less than the average for the population. However, a mastectomy is a difficult operation, and it can be psychologically difficult to recover from it.

Surgery may also be used to reduce the risk of ovarian cancer. Women who had their ovaries removed before menopause not only have a drastically reduced risk of ovarian cancer, but also have a 50% reduced risk of breast cancer, even with hormone replacement therapy. However, this means that you will not be able to have children (unless you store eggs or embryos in a cryobank).

In women with a mutated BRCA gene, the risk of ovarian cancer begins to rise sharply only after the age of 40. Therefore, women under 40 should usually take their time with surgery.

How to tell close relatives?

Most likely, the genetic clinic will not contact your relatives after the cancer test - you yourself must report the results to your family.

You may be given a standard letter to send to your relatives, which lists the test results and contains all the information they need to get themselves diagnosed.

However, not everyone wants to undergo genetic testing. Your close relatives (such as your sister or daughter) may be screened for cancer without a genetic test for cancer.

Family planning

If your predictive genetic test is positive and you want to start a family, you have several options. You can:

Have a child naturally, with the risk that the child will inherit the gene mutation from you.
Adopt a child.
Use a donor egg or sperm (depending on which parent has the mutated gene) to avoid passing the gene to the child.
Get prenatal genetic testing to determine if your baby will have the mutated gene. Then, based on the test results, you can decide whether to continue or terminate the pregnancy.
Use preimplantation genetic diagnosis, a technique that allows you to select embryos that have not inherited a gene mutation. And yet there is no guarantee that the use of this technique will lead to a successful pregnancy.

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All materials on the site have been checked by doctors. However, even the most reliable article does not allow taking into account all the features of the disease in a particular person. Therefore, the information posted on our website cannot replace a visit to the doctor, but only complements it. Articles are prepared for informational purposes and are advisory in nature. If symptoms appear, please consult a doctor.

Genetic tests for cancer - pros and cons

A group of scientists from the United States conducted the largest study in the history of medicine, the purpose of which was to search for genetic mutations that can lead to breast and ovarian cancer. The study involved almost women. As part of the study, women underwent genetic testing for 25 types of genome mutations that can lead to the development of breast and ovarian cancer. In addition, their family histories, their current health status, and their past medical history were studied. Seven percent of the women who took part in the study had at least one of the 25 mutations.

Scientists from the Stanford University School of Medicine and the Fox Chase Cancer Center in Philadelphia (Stanford University School of Medicine and Fox Chase Cancer Center) for the first time carried out such a large-scale work. According to them, this study can clarify the situation with the interpretation of genetic screening, in which there is still no clarity.

"The results of this study will help refine our risk assessments and recommendations for ovarian and breast cancer prevention," says Allison Kurian, MD, Associate Professor of Medicine and Health Research and Policy at Stanford. "Better understanding of cancer risks can help women and their healthcare providers make better informed decisions about cancer treatment options."

For example, Dr. Kurian explained that, based on their research, some women at high risk for breast cancer may consider prophylactic mastectomy, while women at lower risk, such as twice the average risk, may instead have intensive regular screening. , including magnetic resonance imaging of the breast.

Increasingly, women who are tested for a group of cancer-related mutations are getting mixed results. Advances in DNA sequencing have made it faster, easier and cheaper to identify mutations in an ever-growing group of cancer-related genes. However, with the exception of a few well-studied mutations such as BRCA1 and BRCA2, the exact effect of most of them is still not fully understood.

The researchers assessed the mutation status of women with and without cancer. Women were divided into subgroups according to their age, ethnicity and family history of cancer in order to determine the relative risk of developing cancer for each of the mutations.

Dr. Kurian and her colleagues found that 8 kinds of mutations were associated with the development of breast cancer, and 11 were associated with ovarian cancer. The risk of developing cancer in women with mutations increased by 2 to 40 times compared with women without mutations.

For the most part, the results of the new study are consistent with what has already been obtained in smaller studies conducted earlier. But there were also some surprises. It turned out that one of the mutations suggesting an increased risk of developing breast cancer also increases the likelihood of developing ovarian cancer. Three other mutations that were previously thought to increase the risk of breast cancer actually do not.

"One of the surprising findings was an association of an increased risk of ovarian cancer with mutations in a gene called ATM," Dr. Kurian said. “While this risk was relatively small numerically, it was nonetheless statistically significant and, to the best of our knowledge, these data were not previously known. Of course, additional studies will still be needed to provide more accurate recommendations to potential patients when such a mutation is detected during screening.”

The popularity of genetic screening skyrocketed after it became known that Hollywood star Angelina Jolie underwent mastectomy and oophorectomy surgery. The reason for these operations, quite traumatic, was the discovery during the screening of the mutant BRCA1 gene, later called the “Joli gene”. The risk of developing breast cancer in the presence of a mutation in this gene is 87%, and ovarian cancer is 50%. After surgery, this figure dropped to 5%.

In America, women have chosen to follow Jolie: According to a 2014 study, the popularity of the query "preventive mastectomy" on 11 sites analyzed after Jolie's announcement increased from about three thousand to almost one hundred thousand. And information about the detection of mutations in the BRCA1 and BRCA2 genes (mutations of both of them can lead to cancer) began to be searched by 174 thousand people instead of 44 thousand before. With an average cost of $3,000 for a test, the researchers estimated that the Jolie effect would generate $14 million in profits for healthcare organizations in just two weeks.

In addition to the analysis for determining mutations in the BRCA genes, there are already more advanced tests that read near-genes, breakdowns in which are also associated with the development of a number of oncological diseases. Mutations in them often have less penetrance than in BRCA1/2, but it is known that they are indeed associated with some increase in the risk of developing the disease. Among the genes often included in these tests are PTEN, CHEK2, NBN, TP53, PALB2, and a few others.

Genetic testing in Russia

In Russia, tests for individual mutations of the most common hereditary diseases, such as cystic fibrosis or phenylketonuria, are still available. “Unfortunately, we are lagging behind in oncology, also because of the difficulties with registering such tests. In our center, you can take tests based on pyrosequencing technologies (first-generation technologies), which determine several of the most common mutations in the BRCA1 and 2 genes for our population. But so far, of course, this is far from a comprehensive analysis of the entire genome " , - Kamil Khafizov, head of the scientific group for the development of new diagnostic methods based on high-throughput sequencing technologies, told MedNews.

An additional problem is that in Russia, tests based on NGS sequencing (Next Generation Sequencing) technologies do not yet have registration certificates, and therefore cannot be introduced into the practice of diagnostic centers and laboratories. In scientific centers, they are now being carried out as part of research work - due to the fact that patients' access to this kind of diagnostics is difficult, and the issue of paying for tests remains open. There are private companies that offer genetic tests to look for mutations that are responsible, among other things, for a predisposition to specific hereditary diseases. You can also order a complete genome analysis in them. But so far these are not official diagnostic tests, and they are presented, rather, as some kind of entertaining genetics.

The most important point is that not every person who has a defective gene will certainly get cancer. Even if this defective gene is present, each person has a second "healthy" allele received from the second parent.

In the meantime, such a concept as “genetic discrimination” has already developed: in the United States, several lawsuits have already been considered from people who were fired from their jobs after receiving the results of genetic testing. So, one American woman was diagnosed with an 80% chance of developing breast cancer - and the employer hastened to say goodbye to her.

In the United States, such checks have already become routine in many large enterprises: health insurance is expensive, so hiring a person with a high risk of serious illness is not profitable.

What employee genes are undesirable for the employer

In addition to common diseases that require expensive treatment, genes also determine behavior that is undesirable for the employer. Perhaps in the future, testing will be carried out for these genes:

Grm7 is the gene responsible for human cravings for alcohol.
MAOA - people with a mutation in this gene (also called the "warrior gene") will be prone to violence, fights at corporate events and disruption of negotiations.
DATi - mutations in this gene provoke hooliganism and violation of corporate rules.
REV-ERB and Per-2 - the activity of these two genes determines whether a person will be a "lark" or "owl", and, accordingly, whether he will be prone to work schedule violations.
Met158 - This mutation of the COMT gene causes excessive anxiety, carriers of this gene will be prone to post-traumatic stress and obsessive-compulsive disorder.

Today, it is too early to talk about pathogenetic therapy (correction of genes responsible for the development of a number of diseases): this is a matter of a rather distant future. So far, based on genetic tests, it is possible to prescribe personalized therapy in a number of cases, and this can indeed alleviate the course of the disease and even allow people with severe hereditary syndromes to live a full life. But how much screening is needed for healthy people? Unfortunately, many people may react negatively and unconstructively to the information that they have a predisposition to cancer. Because of the experiences, many will no longer be able to adequately perceive the information that the likelihood of developing the disease is not critical. Therefore, the question of whether it is worthwhile to screen the healthy population for all known predispositions, including cancer, is still very controversial.

In general, while we can definitely say: general genetic testing is still too expensive and not very necessary. Experts recommend screening for certain genes only if you are at risk for a particular disease - if, for example, your immediate family suffered from it. In all other cases, such testing only leads to unjustified financial costs and may be an unnecessary cause for concern and anxiety. And, of course, each genotyping test must be accompanied by a consultation with a geneticist: only he can correctly interpret the results and develop a strategy to reduce the identified risks.

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Analysis for genetic predisposition to cancer

Not so long ago, when an oncological disease was detected, patients simply gave up, because it was quite difficult to hope for some kind of positive ending. But now the treatment of such ailments has become possible. Most neoplasms can be easily cured, but only if cancer is detected in time and measures are taken immediately.

Oncology predisposition analysis is a true ally in matters of health. Many countries introduce such a procedure without fail.

There are many tools that can identify the disease at a very early stage. During this period, the state of the disease is not yet manifested in symptoms.

Heredity

There are genes that protect us from cancer, which are inherited from close relatives. However, we do not always receive only positive elements. In the case when twenty or more genes are in a disturbed state, the vulnerability to the development of tumors may increase.

Despite the fact that not everyone talks about this topic in families, it is necessary to find out exactly whether there were people with cancer in your family. This information will help in the future to determine the strategy of prevention or treatment.

To know exactly about the possible risks, it is necessary to do an analysis for a genetic predisposition to cancer.

By taking the cancer predisposition test, you can, if necessary, tune in to a healthier lifestyle and bring in proper nutrition and all the elements that accompany health.

The risks associated with the appearance of oncological ailments can be calculated thanks to twenty-two genes that have their own specific focus. You can check the predisposition to cancer by making an appropriate analysis.

Principle of genetic testing

The information contained in human genes helps to detect cancer susceptibility. In identifying risks, not only the history of diseases of the genus, but also a physical examination are effective: a genetic blood test for cancer becomes the best help in determining the complete picture.

DNA testing for diseases remains relevant throughout life, from birth to death. You can return to it and apply it in any suitable situation. Therefore, it is important, if necessary, to contact specialists and conduct this study.

The history of family diseases, embedded in DNA, helps to determine the degree of probability of the occurrence of an ailment, to identify the very predisposition. In treatment and prevention, this information becomes fundamental.

To know in advance the predisposition to cancer means to be ready to strike back at the disease. It is thanks to an objective assessment of what is happening that it is possible to build a treatment strategy and, with minimal effort, money and time, cope with the disease at a time when the likelihood of treatment effectiveness is greatest.

Another significant point in this diagnosis is the psychological side. It is quite difficult to maintain inner peace and not worry, suspecting that you have an oncological disease. For some, it will be enough to go through the study once and for all to let go of the fears and stories associated with diseases of the family.

Consulting is divided into several important elements:

Collection of information about the patient's history.
Analysis of genetic information.
Search for tools to reduce risks.
Psychological consultation.
Further measures.

If the result of the analysis for a genetic disposition is negative, this does not mean that visits to medical facilities are no longer required. The likelihood of neoplasms is always there, so it is very important not to forget about prevention and examinations by a doctor, which are recommended to be carried out systematically.

How to check the mammary gland?

Quite disappointing forecasts in this area. A large percentage of women are faced with this particular form of cancer. Only timely detection of the disease and competent therapy gives an almost one hundred percent guarantee of healing.

A breast cancer test in the form of an ultrasound examination is necessary for every woman every year.

After a woman passes the age of thirty-five, a mammogram is recommended, which is also enough to do once a year. This procedure is an x-ray of the mammary glands, which is carried out without any pain.

Risk group

Women should be more careful in this matter if the onset of menstruation occurred at a very early life period (up to twelve years).
You should also take your health seriously to those representatives of the beautiful half of humanity who, having crossed the thirty-year milestone, did not give birth.
This group includes women who have relatives who are faced with this disease.
It should also be periodically checked for those who have already been diagnosed with breast disease.

In the event that you have enlarged lymph nodes in the armpit area, seals are palpated, some strange changes occur with the skin, and there is also discharge from the nipples, you should immediately consult a doctor and undergo the necessary examination.

"Equipment for fast and accurate analysis"

Prostate

Prostate cancer is perhaps the most common ailment among the male half, which has stepped over the age of forty-five. To feel calm and confident, it is enough to undergo a transrectal ultrasound examination every two years. You will also need a couple of tests for prostate cancer tumor markers.

These studies reflect the situation quite accurately. It should be borne in mind that food intake is undesirable before the analysis and the prostate gland should be in a calm state, that is, after other similar studies, you must wait at least seven days. With prostate adenoma, as well as prostatitis, an annual study to detect cancer is necessary.

Colon

Another major cancer threat is colorectal cancer. The best way to check this area for tumors is with a colonoscopy, which looks at the colon for abnormalities. In the process, you can also take a piece of tissue for analysis directly from the intestine, as well as remove small polyps.

This procedure is recommended for those over fifty, every five years. In those situations where the pathology was found in close relatives, colonoscopy should be done starting at the age of forty. It is necessary to carefully monitor all changes in the work of the intestine. Colorectal cancer can present with bleeding, constipation, and diarrhea. If these symptoms are present, you should consult a specialist.

Skin cancer

Melanoma is a fairly serious health threat. Given the current trends, the pursuit of tanning and the popularization of solariums, it is imperative to check the health of your skin. Even a simple examination by a doctor may be enough to detect the disease.

A change in skin tone, as well as the structure of those elements that are on it (moles and age spots, seals and ulcers) is a signal to think about the state of the body.

Cervical cancer

Unfortunately, not everyone goes to the doctor on time, so the situation often acquires an irreparable status. This pathology can develop regardless of the age of the woman. Also heredity does not matter.

Cervical cancer can be detected during a routine gynecological examination. In order to respond in time, it is enough just to undergo scheduled inspections. Diagnosis of this area is absolutely painless. It is enough just one procedure a year from the moment a woman begins to live sexually.

Diagnosis includes a meeting with a gynecologist, a colposcopy and a Pap test. The last part of the diagnosis is performed in parallel with the doctor's examination. A woman needs to be wary of various pathologies that are harbingers of oncology.

No matter how confident you are in your health, do not neglect prevention and regular check-ups at the frequency recommended by doctors. The price of carelessness is too high - your health.

Genetic analysis for cancer

The high incidence of cancer forces oncologists to work daily on issues of early diagnosis and effective treatment. Genetic analysis for cancer is one of the modern methods of cancer prevention. However, is this study so reliable and should it be prescribed to everyone? is a question that worries scientists, doctors, and patients.

Indications

Today, genetic analysis for cancer allows you to identify the risk of developing oncopathologies:

mammary gland;
ovaries;
cervix;
prostate;
lungs;
intestines and colon in particular.

Also, there is a genetic diagnosis for some congenital syndromes, the existence of which increases the likelihood of developing cancer in several organs. For example, Li-Fraumeni syndrome indicates the risk of cancer of the brain, adrenal glands, pancreas and blood, and Peutz-Jeghers syndrome indicates the likelihood of oncopathologies of the digestive system (esophagus, stomach, intestines, liver, pancreas).

What does such an analysis show?

To date, scientists have discovered a number of genes, changes in which in most cases lead to the development of oncology. Every day, dozens of malignant cells develop in our body, but the immune system, thanks to special genes, is able to cope with them. And with breakdowns in certain DNA structures, these genes do not work correctly, which gives a chance for the development of oncology.

Thus, the BRCA1 and BRCA2 genes protect women from developing ovarian and breast cancer, and men from prostate cancer. Breakdowns in these genes, on the contrary, show that there is a risk of developing carcinoma of this localization. An analysis for a genetic predisposition to cancer just provides information about changes in these and other genes.

Breakdowns in these genes are inherited. Everyone knows the case of Angelina Jolie. Her family had a case of breast cancer, so the actress decided to undergo a genetic diagnosis, which revealed mutations in the BRCA1 and BRCA2 genes. True, the only thing the doctors could help in this case was to perform an operation to remove the breast and ovaries so that there was no point of application for the mutated genes.

Are there any contraindications to the test?

There are no contraindications to the delivery of this analysis. However, it should not be done as a routine examination and equated with a blood test. After all, it is not known how the result of the diagnosis will affect the psychological state of the patient. Therefore, an analysis should be prescribed only if there are strict indications for this, namely, registered cases of cancer in blood relatives or if the patient has a precancerous condition (for example, a benign breast lesion).

How is the analysis carried out and do I need to prepare somehow?

Genetic analysis is quite simple for the patient, as it is carried out by a single blood sampling. After the blood is subjected to molecular genetic testing, which allows you to determine mutations in the genes.

There are several reagents specific to a particular structure in the laboratory. In one blood draw, a test for breakdowns in several genes can be carried out.

The study does not require special preparation, however, it will not hurt to follow the generally accepted rules when donating blood. These requirements include:

Exclusion of alcohol a week before the diagnosis.
Do not smoke for 3-5 days before donating blood.
Do not eat 10 hours before the examination.
For 3-5 days before donating blood, follow a diet with the exception of fatty, spicy and smoked foods.

How reliable is this analysis?

The most studied is the detection of breakdowns in the BRCA1 and BRCA2 genes. However, over time, doctors began to notice that years of genetic research did not significantly affect the mortality of women from breast and ovarian cancer. Therefore, as a screening diagnostic method (performed by each person), the method is not suitable. And as a survey of risk groups, genetic diagnosis takes place.

The main focus of the analysis on the genetic predisposition to cancer is that if a certain gene is broken, a person has a risk of developing cancer or a risk of passing this gene to their children.

Whether or not to trust the results obtained is a personal matter for each patient. Perhaps, if the result is negative, preventive treatment (removal of the organ) should not be carried out. However, if breakdowns in the genes are found, then it is definitely worth closely monitoring your health and regularly conducting preventive diagnostics.

Sensitivity and specificity of the analysis for genetic predisposition to oncology

Sensitivity and specificity are concepts that indicate the validity of a test. Sensitivity tells you what percentage of patients with a defective gene will be detected by this test. And the specificity indicator indicates that with the help of this test, exactly the gene breakdown that encodes a predisposition to oncology, and not to other diseases, will be detected.

Determining percentages for the genetic diagnosis of cancer is quite difficult, since there are many cases of positive and negative results to be investigated. Perhaps later, scientists will be able to answer this question, but today it can be said with certainty that the survey has high sensitivity and specificity, and its results can be relied upon.

The received answer cannot 100% assure the patient that he will get sick or not get cancer. A negative genetic test result indicates that the risk of developing cancer does not exceed the average in the population. A positive answer gives more accurate information. Thus, in women with mutations in the BRCA1 and BRCA2 genes, the risk of breast carcinoma is 60-90%, and ovarian carcinoma is 40-60%.

When and to whom is it appropriate to take this analysis?

This analysis does not have clear indications for delivery, whether it be a certain age or the state of health of the patient. If the mother of a 20-year-old girl was diagnosed with breast cancer, then she should not wait 10 or 20 years to be examined. It is recommended to immediately undergo a genetic test for cancer in order to confirm or exclude the mutation of genes encoding the development of oncopathologies.

Regarding prostate tumors, every man over 50 years of age with prostate adenoma or chronic prostatitis will benefit from genetic diagnosis in order to also assess the risk. But it is most likely inappropriate to perform diagnostics on people whose families did not have cases of a malignant disease.

Indications for genetic analysis for cancer are cases of detection of malignant neoplasms in blood relatives. And an examination should be prescribed by a geneticist, who will then evaluate the result. The age of the patient for taking the test does not matter, since the breakdown in the genes is inherent from birth, so if at the age of 20 the BRCA1 and BRCA2 genes are normal, then it makes no sense to perform the same study after 10 years or more.

Factors distorting the results of the analysis

With proper diagnosis, there are no exogenous factors that can affect the result. However, in a small number of patients during the examination, genetic damage may be detected, the interpretation of which is impossible due to insufficient knowledge. And in combination with unknown changes with mutations in cancer genes, they can affect the test result (i.e., the specificity of the method is reduced).

Interpretation of results and norms

Genetic testing for cancer is not a rule-of-thumb test, and you should not expect a patient to get a result that clearly states “low”, “medium”, or “high” risk of developing cancer. The results of the examination can only be evaluated by a geneticist. The patient's family history influences the final conclusion:

The development of malignant pathologies in relatives under 50 years of age.
The occurrence of tumors of the same localization in several generations.
Repeated cases of cancer in the same person.

How much does such an analysis cost?

Today, such diagnostics are not paid by insurance companies and funds, so the patient has to bear all the expenses.

In Ukraine, the study of one mutation costs about 250 UAH. However, several mutations must be investigated for the validity of the data. For example, for breast and ovarian cancer, 7 mutations (UAH 1,750) are being investigated, for lung cancer – 4 mutations (UAH 1,000).

In Russia, a genetic analysis for breast and ovarian cancer costs about 4,500 rubles.

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The information on this site is provided for informational purposes only! It is not recommended to use the described methods and recipes for the treatment of cancer on your own and without consulting a doctor!

The composition of the genetic complex:

Breast cancer 1 BRCA1: 185delAG
Breast cancer 1 BRCA1: 3819delGTAAA
Breast cancer 1 BRCA1: 3875delGTCT
Breast cancer 1 BRCA1: 300 T>G (Cys61Gly)
Breast cancer 1 BRCA1: 2080delA

Breast cancer is the most common form of cancer in women. So, in Russia, of all women with cancer, every fifth (21%) has this particular pathology - breast cancer.
Every year, more than 65 thousand women hear a terrible diagnosis, more than 22 thousand of them die. Although it is possible to completely get rid of the disease in the early stages in 94% of cases. This complex includes the determination of mutations in the BRCA1 and BRCA2 genes.

Breast cancer and heredity:

Breast cancer has been considered a risk factor in family history for many years. About a hundred years ago, cases of familial breast cancer were described, passed down from generation to generation. Some families only have breast cancer; in others, other types of cancer appear.
About 10-15% of breast cancer cases are hereditary. The risk of developing breast cancer for a woman whose mother or sister had this disease is 1.5-3 times higher compared to women whose immediate family did not have breast cancer.
Breast cancer is one of the most researched cancers in the world. Every year new information about the nature of this oncological disease appears and methods of treatment are developed.

BRCA1 and BRCA2 genes:

Back in the early 1990s, BRCA1 and BRCA2 were identified as predisposing genes for breast and ovarian cancer.
Inherited mutations in the BRCA1 and BRCA2 genes lead to an increased lifetime risk of developing breast cancer. Both of these genes are related to ensuring the stability of the genome, and more precisely, in the mechanism of homologous recombination for the repair of double-stranded DNA.
In addition to breast cancer, mutations in the BRCA1 gene appear in ovarian cancer, with both types of tumors developing at an earlier age than in non-hereditary breast cancer.

BRCA1-associated tumors are generally associated with a poor prognosis for the patient, since they most often refer to triple-negative breast cancer. This subtype is so named due to the lack of expression of three genes in tumor cells at once - HER2, estrogen receptors and progesterone, therefore, treatment based on the interaction of drugs with these receptors is impossible.
The BRCA2 gene is also involved in the processes of DNA repair and maintenance of genome stability, partly together with the BRCA1 complex, partly through interaction with other molecules.

Mutations characteristic of certain communities and geographic groups are also described for the inhabitants of our country. Thus, in Russia, BRCA1 mutations are mainly represented by five variations, 80% of which are 5382insC. Mutations in the BRCA1 and BRCA2 genes lead to chromosomal instability and malignant transformation of cells in the breast, ovaries, and other organs.

Risk of breast cancer in women with BRCA1 and BRCA2 gene mutations:

Women who carry mutations in one of the BRCA1 and BRCA2 genes have a higher risk of developing breast and ovarian cancer (less often other types of cancer) than others.
It should be emphasized that the degree of risk of developing breast cancer varies depending on the family history. The risk of getting breast cancer again in a woman with a mutation who has already had breast cancer is 50%. The risk of developing ovarian cancer in carriers of a mutation in the BRCA1 gene is 16-63%, and in carriers of a mutation in the BRCA2 gene - 16-27%.

Indications for the appointment of the study:

As part of the program of screening and prevention of breast cancer in order to identify the likelihood of a hereditary predisposition.
Women whose relatives have a mutation in one of the genes.
Women with a family history of breast or ovarian cancer.
Women who have had breast cancer before the age of 50 or who have had bilateral breast cancer.
Women who have had ovarian cancer.