Why is a Pap test prescribed, how is it performed, interpretation of the analysis. Cytological examination of scrapings of the cervix and cervical canal (Papanicolaou staining, Pap test)

The basis for early diagnosis of cervical cancer is the Pap smear ( PAP test). A smear is a scraping of the uterine tissue and examination of the cells under a microscope. Like all human organs, the uterus consists of different layers of cells. The outer surface consists of epithelium; they are constantly replaced with new ones. During the process of maturation and replacement, cells move along the surface, where they are sometimes deposited and can be taken for analysis. The widespread use of simple cytological examination has reduced the incidence of cervical cancer by 2 times. The Pap test is also informative in some other cases. For example, when examining any discharge (urine, feces, sputum, etc.), it is possible to recognize cancer of the bladder, stomach, and lungs. However, the Pap test is most often used in gynecology.

The founder of medical cytology, Georgios Papnikolaou, discovered that malignant tumor cells enter the vaginal secretion. Accordingly, the study of this secretion for pathological cells has become the basis for the early diagnosis of tumors.

A PAP test is mandatory for all women during a gynecological examination, starting from the age of 21, annually. Thanks to the introduction of this test into the work of gynecologists, the incidence of cancer among women was reduced by 60-70%. To obtain the material, the doctor scrapes the epithelium from the surface of the cervix and cervical canal. The analysis is best carried out on days 10-20 of the cycle. In the laboratory, samples are stained for better study. The type of cells, their size, number and structural features, etc. are assessed. The result is usually ready in 1-3 days. The smear may be positive or negative. If the result is negative, there are no atypical cells; the cells have the same size and shape. A positive result reveals cells of different shape and size, and their location is not normal. The smear results indicate what changes were detected:

ASC-US– abnormal cells of the surface epithelium, their appearance is associated with dysplasia, papilloma virus, chlamydia and other infections, atrophy of the mucosa during menopause. It is recommended to be tested to detect the human papillomavirus (HPV), which is one of the main causes of cervical cancer.

LSIL– squamous cell lesions of low severity. The causes may be dysplasia, papilloma virus. The risk of cancer is low. It is recommended to conduct an HPV test and colposcopy.

ASC-H– abnormal epithelial cells. Reasons for detecting cells: precancerous changes, initial form of cancer. Extended colposcopy is recommended.

HSIL– high-grade squamous cell lesions. These lesions can develop into cancer cells. Causes: high-grade dysplasia, cervical cancer. Colposcopy or biopsy recommended .

A.G.C.– abnormal glandular cells. Causes: high-grade dysplasia, endometrial cancer, cervical cancer. HPV analysis, colposcopy, and endometrial curettage are recommended.

AIS– squamous cell carcinoma, cells typical of cervical cancer. Causes: cervical cancer, high-grade dysplasia. Diagnostic curettage and diagnostic excision (removal of a section of mucous membrane) are recommended.

Benign glandular changes– wandering cells of connective tissue. Their detection may be evidence of endometrial cancer or precancerous changes. For women who have not reached menopause and do not have other adverse symptoms, benign glandular cells are considered normal. Diagnostic curettage is recommended.

Despite all the information and high significance of the PAP test, its results depend on the quality of the material taken and some other factors. Therefore, the results may be erroneous.

False positive PAP test– the result indicates the presence of dysplasia, although the woman is healthy. This result may be due to previous inflammatory or infectious diseases of the genital organs, erosion, or hormonal disorders. A repeat PAP test and colposcopy are recommended.

False negative PAP test– indicates the absence of the disease, although it is present. The reason may be incorrect sampling of material for analysis, or a laboratory error. It is recommended to perform a colposcopy in addition to the PAP test.

Possible pathologies in the conclusion of a Pap test:

- inflammatory process - inflammation caused by infection must be treated, after which a repeat PAP test is prescribed. If the examination reveals a papilloma virus, the patient undergoes long-term treatment under the constant supervision of the attending physician.

- atypical epithelial cells - moderate changes, deviations from the norm, but not yet cancer cells. Most often, atypical cells disappear on their own. If dysplasia is detected, treatment is carried out.

— high-level epithelial pathology is a serious cell pathology, but not yet cancer. Only in 1-2% of cases of such a conclusion cancer is detected during biopsy. Further examination, colposcopy, biopsy is required.

— epithelial neoplasia is a serious form of pathology of epithelial cells. A thorough examination and immediate treatment are required.

- cancer in situ - the development of cancer cells in a limited area, without spreading to other areas.

Thus, the Pap test helps to identify not only cancerous and precancerous conditions. During the analysis, inflammation, infections, and cervical atrophy can be detected. Modern cytological examination is one of the most effective methods for diagnosing neoplasms.

Description

Material under study See description

The Papanicolaou staining method is a specially developed method that allows the greatest degree of reliability to identify early precancerous diseases of the cervix.

Cervical cancer ranks third in the structure of malignant neoplasms of the reproductive system. Until 1992, the incidence of cervical cancer was decreasing, but now there is a tendency for this pathology to increase again. The development of the tumor occurs gradually, over several years, so preventive examinations of women using the cytological method are very important.

Currently, when conducting screening programs to detect cervical cancer, precancerous and background conditions, Papanicolaou staining of cellular material is used - the Pap test. The Papanicolaou staining method allows one to assess the degree of maturation of the cytoplasm and stains nuclei with atypia well. The term “atypia” has different interpretations in different countries: in central Europe it is defined as malignancy, in the WHO nomenclature it is “less than dysplastic intraepithelial changes.”

Carrying out a Pap test has a number of features. An important point is to correctly take the material and fix it. The cellular material is taken with brushes of a special configuration in “mirrors” to avoid the ingress of foreign material. The transfer of material should occur quickly, without drying out; rapid fixation of the wet smear in 96% ethanol is required. Papanicolaou staining of smears goes through a number of stages, then the cellular material enclosed in the balm is subjected to cytological analysis.

Material to be examined: scrapings from the endocervix, exocervix, as well as mixed scrapings applied to a glass slide.

Literature

Kulakov V.I. and others. “Modern approaches to the diagnosis of papillomavirus infection of the female genitals and their significance for screening for cervical cancer. Gynecology". 2000; 1 (2): 4 - 8.

Preparation

No special preparation is required for the study. Please note that gynecological tests are taken for children under 16 years of age only in the presence of their parents. Medical offices do not perform cervical scrapings or smears on pregnant women who are 22 weeks or more pregnant because the procedure can cause complications. If necessary, you can contact your doctor to take material.

Interpretation of results

Interpretation of research results contains information for the attending physician and is not a diagnosis. The information in this section should not be used for self-diagnosis or self-treatment. The doctor makes an accurate diagnosis using both the results of this examination and the necessary information from other sources: medical history, results of other examinations, etc.

The protocol for a standardized cytological report, based on the Bethesda classification (revision 2001), as well as on a standardized cytological description according to the Order of the Ministry of Health, consists of the following sections:

quality of the drug: - adequate; - inadequate.
cytogram/description: - epithelial cells within normal limits replaced by - negative for intraepithelial pathology or malignancy; - or describe the detected pathological changes in the epithelium.
cytogram/features: main categories of pathological changes in the epithelium: a) atypical squamous cells (ASC) - PCNS (ASC-US) - undetermined - reactive changes or dysplasia I-weak-CIN-1, most often associated with inflammation; - not excluding B-PIP (ASC-H); - Low grade squamous intraepithelial lesions (LSIL): - H-PIP (ASC-H) - CIN 1 (dysplasia I - mild), human papillomavirus infection - HPV. - high degree of squamous intraepithelial lesions (HSIL): - B-PIP (ASC-B) - CIN 2 (dysplasia II - moderate), CIN 3 (dysplasia III - severe), cancer in situ. - squamous cell carcinoma; b) atypical glandular cells (AGS)
cytogram/other types: other non-neoplastic changes (if detected);
additional clarifications: the specific infectious agent is indicated (if detected).

Pap smear(PAP test, cervical smear, PAP Smear) is an important screening test for the early diagnosis of cervical cancer. Sometimes it is called “cervical smear for cytology, smear for oncocytology.” This accessible, simple and painless method helps to identify precancerous conditions or the development of a cancerous tumor in the cervix, begin treatment at an early stage and prevent the progression of the disease. PAP smears have significantly reduced the incidence and mortality of cervical cancer, especially in developed countries.

Increased risk factors for developing cervical cancer: a large number of sexual partners, early onset of sexual activity (before 18 years of age), a history of genital warts, bad habits (smoking).

It is recommended to undergo regular preventive examination, at least once a year, for all women who are sexually active, especially if she is diagnosed with a high oncogenic risk human papillomavirus or changes in the mucous membrane are detected during colcoscopy. Next, based on the results of the cervical smear, the doctor will determine how often you will need to repeat this test.

The gynecologist takes a scraping of the cells lining the cervical canal and applies it to a glass slide. Usually 2 preparations are prepared: from the endocervix (the mucous membrane covering the vaginal part of the cervix) and the exocervix (the mucous membrane lining the cervical canal). A special Papanicolaou stain is used to identify atypical cells. The smears are then examined under a microscope to identify possible changes: inflammation, abnormal or cancerous cells.

Preparing for a Pap test. To obtain the most accurate result, a number of conditions must be met before performing a Pap test. It is not recommended to conduct an examination during menstruation, in the presence of an inflammatory process. 48 hours before taking a PAP smear, you must refrain from sexual intercourse, the use of tampons, the use of any vaginal creams, suppositories and medications, douching and vaginal douches. A smear should be taken before a gynecological examination, colposcopy or no earlier than 48 hours after these manipulations. It is also advisable to take a shower instead of a bath 2 days before the Pap test.

Interpretation of results. First, the quality of the smear is assessed: high-quality, low-quality. If the quality of the smear is unsatisfactory, the smear must be repeated. The Pap smear can be positive or negative (Pap class I).

Norm. Normally, there are no atypical cells; all cells are of the same shape and size (negative Pap smear).

Cytological smear interpretation, Pap test results. The presence of cells of different shapes and sizes, their pathological position is characterized as a positive Papanicolaou smear. These tests show the presence of atypical cells, which often sounds scary to women who do not understand what it means. A positive smear result for atypical cells does not mean that you have cancer or a precancerous condition, but only indicates the need for further research. The cause of the appearance of atypical cells may be the presence of inflammation (chlamydia, herpes infection, gonorrhea, trichomoniasis), infection with the human papillomavirus (HPV). These changes are more often characterized as grade II dysplasia. In this case, it is necessary to carry out the necessary treatment and repeat the smear after 3-6 months. With human papillomavirus infection, koilocytosis of cells is often detected. Koilocytes are squamous epithelial cells of irregular shape, with clear boundaries. Koilocytes vary in size and are usually larger than normal cells. The nuclei are enlarged to varying degrees, the nuclear membrane is uneven and folded. Around the nucleus there is a clearing zone of the cytoplasm.

Cytological classification according to Papanicolaou:

1st class - normal cytological picture;
2nd class - changes in cell morphology caused by an inflammatory process in the vagina and (or) cervix;
3rd class - single cells with abnormalities of nuclei and cytoplasm (suspicion of malignant neoplasm);
4th class - individual cells with obvious signs of malignancy;
Class 5 - a large number of typical cancer cells. The diagnosis of a malignant neoplasm is beyond doubt.

When classifying according to the Bethesda System (TBS), the following terms may appear in the cytologist’s report:

ASCUS (atypical squamous cells of undetermined significance) or APNZ (squamous cell atypia of undetermined significance);
CIN (cervical intraepithelial neoplasia) or CIN (cervical intraepithelial neoplasia) (the term is used as a synonym for cervical dysplasia)
LSIL Low-Grade Squamous Intraepitelial Lesions) or N-PIP (low-grade squamous intraepithelial lesion)
HSIL (High-Grade Squamous Intraepitelial Lesions) or B-PIP (high-grade squamous intraepithelial lesion).

If the cytologist's conclusion indicates mild, moderate, or severe dysplasia (N-PIP and V-PIP), in these cases colposcopy is performed, as well as separate diagnostic curettage of the mucous membrane of the cervical canal and the body of the uterus with histological examination of scrapings.

How much does it cost to have a Pap smear test?
Review of prices for Pap tests in leading laboratories in Moscow(as of August 2014)
— 825 rubles + 250 rubles for taking a smear;
— 1,100 rubles + Taking a smear/scraping: 390 rubles
— 1730 rub.
1545 rub. + 380 rub. for taking the material.
— 1020 rub. + 300 rub. for taking a smear
— 1030 rub. + taking a smear 390 rub.

S.I. Rogovskaya, V.N. Prilepskaya. Prevention of human papillomavirus infection and cervical cancer (Gynecology. Volume 9/N 1/2007::: Topic: PATHOLOGY OF THE CERVIX AND GENITAL INFECTIONS)

Essentially, Papanicolaou cytological examination is one of the staining methods for microscopic examination and is based on the different reaction of cell structures to acidic and basic dyes.
But the undoubted merit of George Papanicolaou is that he was the first to use this staining method and substantiate its importance for the diagnosis of precancerous and cancerous diseases of the cervix. The first description of the method appeared in 1928, and in 1943 the method officially began to be used for the cytological diagnosis of cervical cancer practically worldwide. Currently, the Pap test (named after the scientist) is the main diagnostic method for this common fatal disease in women.

How is the PAP test performed?

After collecting the material, it is sent to the laboratory, where it is first stained with hemotoxylin or orange with basic dyes, and then with an acidic dye.
often eosin. As a result of staining, changes in the nuclei and cytoplasm of cells can be easily determined. First, the nature of the pathological process is determined - inflammatory,
reactive, malignant, then, based on the composition and changes (degrees of severity of signs of atypia) of cellular elements, a differential diagnosis of malignant and benign processes is carried out.

How is the PAP test assessed?

Since 1954, a classification into five classes has been used, which was developed by D. Papanicolaou. This classification is still used in some laboratories in Russia, but in world practice it is not used and represents
historical interest only.

Classes (1954)	Cytological picture
	Normal cytological picture
	Changes in the morphology of cellular elements caused by an inflammatory process in the vagina or cervix
	Single cells with abnormalities of the cytoplasm and nuclei. The diagnosis is not clear enough; a repeat cytological examination is required or a histological examination of biopsy tissue is necessary to study the condition of the cervix.
	Individual cells with signs of malignancy: nuclear enlargements, nuclear changes, abnormal cytoplasm, chromatic aberrations
	A large number of malignant cells

What systems are used to evaluate the Pap test?

WHO classification

In 1968, the World Health Organization proposed a new descriptive test scoring system based on morphological criteria. Papanicolaou class 2 was divided into three forms of atypia, class 3 was described in three forms of dysplasia - mild, moderate and severe, class 4 was described as in situ cancer, and 5 as invasive cancer.

Description (1968)	CIN (1978)	Bethesda 1988	Classes (1954)
Fine	Fine	Negative for intraepithelial lesion or malignancy (NIL)	Class I
	Inflammatory atypia or tumor	ASCUS	Class II
HPV	HPV	Low-Grade SIL	Class II
Atypia with HPV	Atypia, "condylomatous atypia" and "koilocytic atypia"	Low-Grade SIL	Class II
Mild dysplasia	I CIN	Low-Grade SIL	Class III
Moderate dysplasia	II CIN	High-Grade SIL	Class III
Severe dysplasia	CIN III	High-Grade SIL	Class III
Cancer in situ	Cancer in situ	High-Grade SIL	Class IV
Invasive Cancer	Invasive Cancer	Invasive Cancer	Class V

CIN classification

In 1978, Richart proposed a histological classification and introduced the term CIN (cervical intraepithelial neoplasia) - cervical intraepithelial neoplasia, the degrees of which corresponded to the degrees of dysplasia of the WHO classification.

Bethesda system classification

In 1988, the US National Cancer Institute proposed a new
cytological, Papanicolaou test evaluation system - Bethesda system, which is still used in world medicine. All changes were divided into 2 types - ASCUS (atypical squamous cells of undetermined significance) squamous cell atypia of undetermined significance and SIL (Squamous Intraepitelial Lesions) squamous intraepithelial lesions , which in turn were divided into 2 categories - low severity (LSIL - Low-Grade Squamous Intraepitelial Lesions) and high severity - (HSIL - High-Grade Squamous Intraepitelial Lesions)

What are benign cell changes?

In some processes, benign changes occur in the epithelial cells of the cervix. These changes are assessed by the Pap test as inflammatory atypia, atypia caused by papillomavirus, or as mixed atypia or as atypia of undetermined significance.

Causes of benign changes

Pregnancy
Exposure to chemicals (medicines)
Infection caused by actinomycetes
Atrophic vaginitis
Radiation injury (with radiation therapy)
Intrauterine contraceptive device (spiral)

What are atypical squamous epithelial cells

What is cervical dysplasia

Dysplasia (or cervical intraepithelial neoplasia - CIN) of the cervix is a pathological process that begins in the transitional metaplastic epithelium and is expressed in the appearance of atypical cells against the background of increased proliferation of basal and parabasal cells. Dysplasia can progress to squamous cell carcinoma (cervical cancer ) or spontaneously regress or regress after treatment.

What is ASCUS

What is Low-Grade SIL

What is High-Grade SIL

What are atypical glandular cells

Using the Pap test, atypical glandular epithelial cells can be identified.

What to do if there is an abnormal Pap test

For cytological features of the LSIL type (low-grade cervical intraepithelial lesions or features of HPV and CIN I), the International Agency for Research on Cancer recommends:

Options	Events
Option 1	Carry out a repeat cytological examination after 3 months. Then, if the smear is normal (negative), repeat again after 6 months, after 1 year and after 2 years. If LSIL (positive) results are repeated, refer the woman for colposcopy
Option 2	Perform a colposcopy. In the absence of abnormal colposcopic signs (normal), the cytological examination should be repeated after 6 or 12 months (depending on whether an oncogenic type of HPV is present or not). When indicated, a biopsy and diagnostic curettage of the mucous membrane of the cervical canal is performed. If the results of colposcopy are unsatisfactory (when an adequate conclusion cannot be made), therapy for the concomitant pathology should be prescribed (anti-inflammatory or estrogen therapy is possible) and colposcopy should be repeated

This is a test that evaluates the structure of the cells of the cervix. It received its name in honor of the Greek physician Papanikolaou, who first introduced it into medical practice in the 50s of our century. In Russia, this study is also called the Pap test or its other name is “cervical cytology” (from the word “cyto” - cell). A Pap test helps identify various changes in the structure of cervical cells that can lead to the development of cancer. Detection of these changes and their appropriate treatment prevents the development of cancer.

Thus, the main purpose of performing cytology is prevention (i.e. prevention) of cancer. For example, in the USA, where a Pap test is mandatory during preventive examinations by a gynecologist, the incidence and mortality from cervical cancer has decreased by 70% over the past 40 years.

Can a Pap test detect cervical cancer?

Yes. But the main role of the test is to detect changes in cells that usually precede the appearance of cancer. These changes are also called precancerous changes. Several years usually pass from the appearance of abnormalities in the structure of cells to the appearance of cancer. And if a Pap test is regularly performed during this time interval, which will reveal these abnormalities, then with the help of early treatment it is possible to prevent the development of cancer or to detect it at very early stages. To confirm and clarify the diagnosis of cancer detected by cervical cytology, other additional studies are carried out.

Does the Pap test help detect or prevent cancer in other organs?

No. This test allows you to evaluate the structure of only the cells of the cervix and no other organs. The cervix is a narrow tube located in the lower part of the uterus, which at its outer end opens into the vagina. On the outside, it is covered with thin pink epithelium, which in appearance resembles the tissue in your mouth. This epithelium consists of 4 layers of cells of different structures and is called “stratified squamous epithelium”.

The inside of the neck is covered with epithelium, consisting of one row of cylindrical cells. Therefore, this epithelium is called “columnar epithelium”. It has a bright red color. Cytology of the cervix examines the structure of cells located both outside and inside.

How is cervical cytology performed?

A Pap test is performed during a gynecological examination. The doctor will ask you to undress and lie down on the gynecological chair. In order to see the cervix, the doctor will insert a special instrument called a speculum into the vagina. After removing vaginal discharge, using a small brush and a wooden spatula, the doctor makes a scraping for examination from the outer and inner surfaces of the cervix. This is a completely painless procedure lasting 5-10 seconds.

The cells are applied to special glasses and sent to the laboratory, where they are examined under a microscope by a cytologist. The cytologist determines whether the sent material contains cells with a changed structure or not, and reports this to the gynecologist (usually in the form of a written report). Since the doctor scrapes them off when collecting cells, some women, after cytology, may have extremely slight, spotting bleeding from the genital tract over the next 1-2 days.

Do I need to prepare in any way for a Pap test?

Yes. To collect cytology, come in the first few days after the end of menstruation. 2 days before the PAP test, it is not recommended to use any medications for vaginal use, spermicidal contraceptives, vaginal lubricants, or moisturizers. All this can affect the true picture of the structure of cervical cells.

It is not recommended to conduct a study if there are symptoms such as itching and, which may indicate a possible infection. In this case, it is better to consult a doctor to find out the cause of these symptoms.

How often should cytology be performed?

The first Pap test should be performed immediately after sexual activity begins. Then once a year, during your annual preventive visits to the gynecologist, regardless of whether you are sexually active or not. If for 3 years in a row you have good Pap test results (i.e., no changes in the structure of cervical cells are detected), then a Pap test is performed once every 2-3 years until the age of 65. After age 65, the Pap test can be discontinued, provided all previous results have been good.

Of course, the frequency of Pap tests may vary. Your doctor may recommend performing this test more frequently if you have a history of cervical cell abnormalities and/or have risk factors for cancer, such as:

more than one sexual partner or a partner who has other sexual partners besides you
early onset of sexual activity (before 18 years of age)
past or current sexually transmitted diseases (), especially such as genital herpes and papillomas on the genitals
HIV infection
smoking

How accurate is the Pap test?

Like any test in medicine, the Pap test is not always 100% accurate. Those. Sometimes the cervical cytology report describes pathological changes, but in fact they are absent. This result is called a false positive. Or, on the contrary, the conclusion of the Pap test is good, while in reality there are disturbances in the structure of the cells. This result is called a false negative.

The most common cause of false-positive cervical cytology results is the presence of inflammation in the vagina or cervix. In this situation, if the doctor sees an abnormal Pap test + signs of inflammation, it is usually recommended to carry out a course of anti-inflammatory treatment and repeat the Pap test after its completion.

The reasons for a false negative Pap test may be the following:

too few cells were on the glass for examination
presence of infection in the vagina and cervix
blood in the test
use of vaginal medications and lubricants 1-2 days before the test

Proper preparation and regular testing (as recommended by your gynecologist) helps reduce the frequency of unreliable Pap test results to a minimum.

A What if the Pap test shows abnormal cells?

In this case, the doctor recommends additional examination. This could be as simple as repeating the Pap test some time after the first result. Sometimes a special test is prescribed - colposcopy. - this is a study when the cervix is examined by a gynecologist under high magnification (usually 7-15 times) using an instrument called a colposcope (similar to a large microscope). During such an examination, the doctor can see the area where the pathological changes detected in the Pap test are located.

In addition, during colposcopy, the doctor decides whether you need it to clarify the diagnosis. Depending on the result of the Pap test and colposcopy (with or without a biopsy), your doctor may recommend either simple observation with periodic repetition of cervical cytology, or removal of the detected pathological cells.