Pap test with interpretation of the cytological examination of the smear. Cytological analysis: how the Pap test is performed and why it is needed

general information

The Pap test can quite effectively detect precancerous changes in the epithelium - cervical intraepithelial neoplasia varying degrees gravity.

This type of examination is mandatory for women over 30 years of age, especially those who have previously or are currently diagnosed with high-oncogenic risk human papillomavirus, as well as for women who have areas of altered epithelium detected during colposcopic examination of the cervix.

The number of preparations (glasses) can be from 1 to 3. Most often, it is necessary to examine two preparations - epithelium from the endocervix and exocervix. The material must be collected using special cytobrushes. Methodology for preparing a specimen for Papanicolaou cytology.

The biomaterial is taken using a special cervical brush. Immediately after taking the biomaterial, an imprint smear is prepared by touching all surfaces of the cytobrush to the surface of the slide. The probe is disposed of. The prepared smear is dried in air. The glass with the dried smear is placed in a cuvette and fixed at 96%. ethyl alcohol rectified within 5 minutes.

Place the finished drug in individual packaging (plastic or paper bag), attach it to the direction with a stapler and send it to the laboratory. It is allowed to store glasses with fixed or dried smears in sealed packaging at a temperature of 2-8 oC for 10 days.

According to international standards, the first Pap test is performed 3 years after becoming sexually active or at age 21 (whichever comes first). Then - once a year. If for 3 years in a row the results of the Pap test do not reveal changes in the structure of the cells of the cervix, the 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 negative.

Preparing for the study

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

Interpretation of results

The Pap smear can be positive or negative (Pap class I). Normally, there are no atypical cells; all cells are of the same shape and size (negative Pap smear). The presence of cells of different shapes and sizes, their pathological position is characterized as a positive Papanicolaou smear.

Cytological classification according to Papanicolaou

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

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Used in gynecology, the Papanicolaou smear is a simple, painless test that is used to diagnose endometrial and cervical cancer. It is based on the work of George Papanicolaou, who discovered that cancer cells shed into vaginal secretions.

Research principle

Every year, 500 thousand women are diagnosed with cervical cancer worldwide. Over the past 30 years, the incidence has decreased by more than 2 times. This is largely due to widespread use screening cytological examination.

The mainstay of early detection of cervical cancer in large populations for the last 60 years has been the Papanicolaou smear.

What is a Pap test (also called a Pap smear)?

This is an exfoliative cytological procedure with staining of the resulting material. In other words, a Pap smear is a scraping of the tissues of the superficial layer of the cervix and examination of the resulting cells under a microscope after treatment with special dyes. The method is also used to detect cancer Bladder, stomach and lungs. Any body secretions (urine, feces, sputum, prostate secretions), as well as biopsy material, are suitable for it.

However, the Pap smear is most often used for diagnosis initial stages. The material is taken from the transition zone of the cervix, where the columnar epithelium cervical canal borders on flat stratified epithelium lying on the vaginal part of the cervix. The resulting sample is placed on a glass slide, stained, and examined under a microscope to look for abnormal or malignant cells.

What does it show?

It detects precancerous and malignant changes (cancer) of the cervix. After a few minutes, the analysis can reveal either her cervix at a stage when the tumor is not accompanied external changes and damage to surrounding tissues. At this time, the malignant neoplasm is successfully cured. Therefore, a Pap test is recommended regularly for all women over the age of 21.

Pap test based on liquid cytology helps in detection. At the same time, additional research to detect viral DNA. This pathogen is a major risk factor for the development of cervical cancer. When using the liquid cytology method, the material is placed not on a glass slide, but in a test tube with a liquid preservative.

A smear for the human papillomavirus is prescribed in case of doubt about the results of a cytological examination. Both traditional analysis and liquid-based cytology have equal diagnostic effectiveness. Both of these methods can be used in practice.

HPV testing is not performed in women under 30 years of age due to high prevalence of this infection in the specified age group. In addition, the infection is often transient, meaning it can disappear.

Although the interpretation of results largely depends on the qualifications and experience of the doctor, there are objective ways to improve diagnostic accuracy. Thus, special computer programs. Some clinics retest some swabs for quality control.

Much depends on proper preparation women for research.

Preparing for the test

The analysis is carried out during scheduled inspection at the gynecologist. You need to inform your doctor about the medications you are taking. contraceptives and other hormonal drugs.

Special preparation for the Pap test:

• refrain from vaginal intercourse for 48 hours before the test;
• at the same time, do not use vaginal tampons, douche, or use medications or contraceptives inserted into the vagina;
• It is advisable to pre-treat, if any.

Pap test, in other words Pap smear

On what day of the cycle should I take the test?

There are no special restrictions. The only condition is the absence of menstrual or other uterine bleeding. However, the analysis can be taken even during menstruation, but its accuracy is reduced.

If a woman has bleeding or cervicitis (inflammation of the cervix), this is not a contraindication for the study. These symptoms may be caused by precancer or malignancy, which can be detected during screening.

Indications

For timely diagnosis malignant tumors, a simple method that has no contraindications is needed. A cervical Pap test is a screening test that allows most women to be examined regularly.

Table. When is the best time to do a Pap test?

Some women are at risk of developing malignant tumor higher than average. They may need more frequent testing.

At-risk groups:

• women infected with HPV or HIV;
• survivors and sexually transmitted diseases;
• patients with weakened immune systems;
• early onset of sexual life;
• multiple sexual partners;
• having;
• smoking or drug use.

A Pap test during pregnancy is mandatory to exclude infections and precancerous diseases. No danger for expectant mother and he is not carrying a baby.

How is it carried out?

To carry out the analysis the following are used:

• gynecological chair and lamp;
• metal or plastic vaginal dilator;
• examination gloves;
• cervical spatula and special brush;
• test tube or slide.

How is a Pap smear performed?

The patient is positioned on a gynecological chair. Her tailbone should be at the edge of the chair to ensure a good view when inserting the dilator.

A speculum is placed into the vagina. It is recommended to warm it up first warm water for the comfort of a woman. In some clinics, if necessary, it is not used a large number of special lubricant to facilitate insertion of the expander.

The surface of the cervix should be completely open and thoroughly examined by the doctor. It is necessary to visualize the squamous epithelium, transition zone and external os. The transition zone is the area where squamous epithelium transforms into glandular epithelium. HPV affects this area. Therefore, cell selection is carried out in this zone. In addition, material is taken from the surface of the cervix and from the area of ​​the external pharynx.

If necessary, the cervix is ​​cleaned of secretions with a soft swab. The material is taken with a spatula or a special brush, turning them around its axis.

Depending on the equipment used, the resulting material is either placed in a special solution, which is in a test tube, or on a glass slide, onto which a fixative is then applied and placed in an alcohol solution.

The study is completed within a few minutes. It's painless. After the analysis, it is better to avoid sexual intercourse, use of tampons and douching for 5 days.

Can I take a bath after a Pap test?

Complications and limitations

Adverse effects from a Pap smear are very rare. The woman should be warned about the possibility of weak bloody discharge. This is fine. Another complication is the addition of an infection. However, its likelihood is very low, since the procedure does not damage blood vessels and sterile instruments are used.

Although the Pap smear is one of the best screening methods, it has its limitations. The sensitivity of a single Pap test in detecting cervical dysplasia averages 58%. This means that the existing disease will be detected in only half of the women who actually have it. Approximately 30% of women newly diagnosed with cervical cancer had negative result analysis performed.

HPV testing has higher sensitivity. In the group of women over 30 years of age, it allows diagnosing dysplasia in 95% of cases. However, in younger women such analysis becomes less informative.

results

If the results of the Pap test show the presence of abnormal cells, the patient is scheduled for colposcopy. This test helps detect precancerous and malignant changes through a biopsy - removing a piece of tissue for microscopic analysis. If a precancerous disease is detected and treated in time, this will save the patient from cancer.

How many days does the analysis take?

The result is ready in 1-3 days; when using automatic analyzing systems, the time to obtain the result is reduced. In some public clinics The waiting time for results increases to 1-2 weeks.

There are 5 classes of smears:

1. Normal, no atypical cells.
2. Cellular changes associated with inflammatory disease vagina or cervix.
3. Single cells with altered cytoplasm or nucleus.
4. Individual malignant cells.
5. Atypical cells in large numbers.

The Bethesda classification system is also used. In accordance with it, a low and a high degree of change are distinguished. Low includes koilocytosis and grade I CIN. High includes CIN II, III and carcinoma in situ. This corresponds to smear classes 3-5.

As a result of the analysis, you can see the following designations:

• NILM is normal, corresponds to smear class 1.
• ASCUS – atypical cells of undetermined significance. They can be caused by dysplasia, HPV infection, chlamydia, and mucosal atrophy during menopause. HPV testing and a repeat Pap test after a year are necessary.
• ASC-H is an atypical squamous epithelium that occurs with CIN II-III degrees or early cancer. The tumor occurs in 1% of women with this result. An extended colposcopy is prescribed.
• LSIL - a small number of altered cells, indicates mild dysplasia or HPV infection. HPV testing is necessary, and if the virus is detected, colposcopy. A repeat Pap smear is performed after a year.
• HSIL – pronounced changes corresponding to grade II-III CIN or cancer in situ. Without treatment within 5 years, cancer will develop in 7% of these patients. Colposcopy with biopsy or diagnostic excision is prescribed.
• AGC - modified glandular cells, which occur with dysplasia and cancer of the cervix and uterine body. HPV testing, colposcopy, and curettage of the cervical canal are prescribed. If a woman is over 35 years old and has irregular uterine bleeding, separate diagnostic curettage.
• AIS – carcinoma in situ, an early stage of a malignant tumor. Colposcopy, diagnostic excision, and separate diagnostic curettage are indicated.
• High-grade SIL – squamous cell carcinoma.
• Adenocarcinoma is a tumor that develops from glandular epithelium cervical canal.

Benign glandular changes are considered a normal variant in women with normal menstrual cycle. If there is irregular bleeding, or the patient is in menopause, diagnostic endometrial curettage is indicated to exclude uterine cancer.

For any version of the Pap test, consultation with a gynecologist is necessary.

This study received its name from the Greek scientist Georgios Papanikolaou, a pioneer of cytology and early cancer diagnosis. The Pap test helps to identify those cellular changes in the cervical epithelium, which can subsequently lead to cancer, and begin treatment in a timely manner. Today this analysis is used all over the world, and it has already saved the lives of hundreds of thousands of women.

How is a PAP test performed?

The procedure for collecting cell material is painless. It is carried out during an examination in a gynecological chair. First, using a cotton swab, the doctor cleans the surface of the cervix from secretions, then using a special brush, the material for research is taken, which is applied to a glass slide. This piece of glass will go to the laboratory, where it will be studied under a microscope.

How often should a cytological smear be taken for analysis?

The Association for Cervical Pathology and Colposcopy gives the following recommendations in this regard.

All women should begin undergoing cytological examination 3 years after the start of sexual activity, but no later than 21 years.

Women from 21 to 49 years old need to undergo a cytological examination every 3 years, and from 50 to 65 years old - every 5 years. However, there is a category of women with weakened immune systems (HIV-infected, after an organ transplant, after chemotherapy or chronic use of steroids) who should undergo this test annually. Gynecologists also advise women over 30 years of age to normal indicators cytological smears At every three-year checkup, do a human papillomavirus DNA test.

Women 65 years of age and older who have had three cytology tests negative in the past 10 years may no longer have cytology screening for cervical cancer. However, this does not apply to those who have previously been treated for cervical cancer, carriers of HIV infection or women with weakened immune systems. They need to keep testing.

A special group consists of women who have undergone surgery to remove reproductive organs. After a complete hysterectomy (removal of the uterus along with the cervix), cytological screening is no longer necessary, unless this operation was performed as part of the treatment of cancer or pre-cancer of the cervix. If the amputation affected only the uterus, without removing the cervix (supravaginal amputation), then cytological screening must be continued, adhering to general principles prevention of cervical cancer.

How to prepare for research?

First of all, a cytological smear is not taken during menstruation and during inflammatory processes of an infectious nature.

In order not to blur the pictures, two days before the study it is not recommended to douche, insert tampons, suppositories or creams into the vagina.

You should also abstain from sexual intercourse two days before visiting a gynecologist.

What the results say

Typically, your doctor will receive your Pap test results within 1–2 weeks. And if atypical cells are found in them, this does not mean a death sentence. An identified deviation from the norm is only a call to be wary and pass additional examinations. In this case, colposcopy is first prescribed. This is a procedure for examining the vulva, vagina and cervix using a special device - a colposcope, which helps to identify the presence of lesions of the cervical epithelium and determine their nature. And based on this study, the doctor decides whether a cervical biopsy is needed.

Pap test is taking a sample for analysis to identify gynecological diseases in a woman. Pap test, cytology smear, cervical smear, cytological smear, Pap test - these are all variants of the name of the same gynecological examination, very important, informative and at the same time very simple. A Pap test or cytology smear is required during a gynecological examination for every woman.

· what is the pap test for?

Pap test allows you to detect the slightest changes in microflora and cellular composition vagina, cervical canal and cervix, which can subsequently lead to dysplasia and the development of cancer. When regular checkups a gynecologist and a papa test, such changes will be detected at the earliest stage, allowing you to prescribe and carry out the maximum possible effective treatment. This is very important, since in Ukraine alone, for example, cervical cancer is the second most common cause of female mortality from oncological diseases. The only way to identify a precancerous process is regular gynecological examination, cytology smear, And

The Pap test is used for early diagnosis of dysplasia () and cervical cancer. At the same time, a smear for cervical cytology alone cannot always be a confirmation of cancer; for diagnosis it has great importance colposcopic picture and the results of analysis for HPV (papillomavirus, human papillomavirus). The final reliable diagnosis is obtained by performing a biopsy - laboratory test a fragment of tissue suspicious for cancer taken for analysis.

A smear for cytology, according to the rules, is taken from the canal and surface of the cervix with a special spatula. The taken material is applied to glass and sent to the cytology laboratory. In the laboratory, a cytological smear is stained using the Papanicolaou method, and then laboratory doctors carefully examine the sample for any abnormalities. cellular structure, assessing the reactions of the studied material to reagents.

· When and Who needs a dad test?

1. Every woman should have a cytological smear at least once a year, starting at the age of 18 or the beginning of sexual activity. In the absence of sexual intercourse, a Pap test is permissible once every 3 years.

2. Twice a year a cytological smear is recommended when using hormonal contraception, as well as women who suffer from genital herpes.

3. The reason for more frequent cytological examinations is frequent change female sexual partners, overweight (obesity), infertility, presence genital warts genitals.

The incidence of cervical cancer increases with age, so cytology smears must be done regularly throughout life. A woman should systematically undergo a cytological smear and Pap test even after menopause has occurred.

· Risk factors for developing cervical cancer:

1. Early onset of sexual activity;

2. Multiple sexual partners;

3. Viral infections, particularly HPV, herpes virus (HSV), or HIV;

4. Presence of cancer of the reproductive system in the past;

5. Weakened immune system;

6. Smoking.

· preparation for a cytological smear

The only obstacle to performing a papa test is menstruation; in its absence, a cytological smear is taken at any time. It is recommended to abstain from sexual intercourse 48 hours before the test; you should not use vaginal creams and suppositories, douching and taking baths and vaginal showers.

· Pap test: results and evaluation of the analysis

In gynecology there are five various stages development of pathology. At the first stagedad - the test is negative - that is, health is normal. Positive results Pap test gives results at stages 2, 3, 4 and 5 of pathology.

Stage 1: means a normal cytological picture (absence of cells with any abnormalities), characteristic of healthy women in gynecological terms.

Stage 2: morphological changes in cells are observed, which are caused by the inflammatory process. This stage is generally normal, but requires a more thorough examination of the woman to identify the causes of inflammation, the presence of infection, etc.

Stage 3: detection of single cells with abnormalities in the structure of the nuclei and cytoplasm. This stage means the presence of a malignant process is suspected. In this case, it is necessary to take a repeat cytological smear and histological examination and targeted biopsy to confirm or remove suspicions.

Stage 4: this stage means that individual cells with obvious malignant changes have been detected. In this case, carrying out is mandatory!!!

Stage 5: At this stage, a large number of obvious typical cancer cells are determined. Such results of the pap test mean that the diagnosis of a malignant process, that is, cancer, is beyond any doubt.

Despite the fact that a smear for cervical cytology has a fairly high reliability, the final diagnosis is established exclusively after colposcopy and the results obtained from a cervical biopsy.

Among other things, the pap test does not provide any information about the condition of the ovaries and uterus, and they are also at risk of cancer. Therefore, if there is a suspicion of cancer and a negative pap test, it is mandatory to conduct a vaginal ultrasound and examination of the pelvic organs in the woman.

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SYNONYMS

Pap smear, Pap test, Pap test, Pap smear.

RATIONALE FOR PAP smear

The morphological analysis method is based on the study and evaluation of cellular material.

PURPOSE OF PAP TEST

Revealing morphological features cells characterizing a specific pathological process.

INDICATIONS FOR PAP smear collection

Screening for cervical cancer (see section “Cervical dysplasia”).

PREPARATION FOR THE STUDY (PAP smear)

During the day before the test, you should not douche or use vaginal preparations. It is advisable to abstain from sexual intercourse for 1–2 days before the test. You cannot take material for research during menstruation.

PAP TEST TECHNIQUE AND FOLLOW-UP CARE

Material for research: scraping from the cervical canal and from the surface of the ectocervix. To obtain the material, the following instruments are used: Eyre's spatula (for taking smears from the surface of the ectocervix), Volkmann spoon, screenet, endobranche (for taking endocervical smears, etc.). To obtain optimal cytological results, samples should be taken separately from the ectocervix and endocervix. The material is taken before bimanual examination. After examining the cervix using mirrors without preliminary treatment, lightly scrape the surface of the pathologically changed area or the surface of the ectocervix around the external os. Material is taken from the cervical canal after removal of the mucus plug. From the resulting material, prepare one thin, uniform smear over the entire length of a clean, dry glass slide and fix it by air drying. The dried smear is labeled.

INTERPRETING PAP smear results

CLASSIFICATION OF CERVICAL PAP smears

• First class - no atypical cells, normal cytological picture.
• The second class is a change in the morphology of cellular elements caused by an inflammatory process in the vagina and/or cervix.
• The third class is single cells with abnormalities of the cytoplasm and nuclei.
• The fourth class is individual cells with obvious signs of malignancy: increased nuclear mass, cytoplasmic abnormalities, nuclear changes, chromosomal aberrations.
• Fifth class - a large number of atypical cells are observed in the smear.

In practical work, it is advisable to use modern standardized reports of the main types of this classification or cytological reports corresponding to certain histological diagnoses.

In 1989 Working group The National Cancer Institute, meeting in Bethesda (Maryland, USA), proposed a two-stage system for assessing the results of a cytological study, later called the “Maryland” or “Bethesda” system. Similarities clinical manifestations, the results of cytological and molecular biological studies, as well as the same treatment tactics, made it possible to combine koilocytosis (see section “Hapillomavirus infection of the genital organs”) and CIN I and classify them as a low degree of PIP. For the same reasons, CIN II, III and carcinoma in situ were classified as high degree PIP. According to the Maryland system, unclassified atypical squamous epithelial cells include cells that do not meet the criteria for changes in one or another degree of malignancy. This category does not include atypical cells that arise from inflammation, atrophy or repair, since according to the Maryland system they are considered benign.

Standardization of cytological examination results facilitates their comparison and reduces the likelihood of diagnostic errors. In addition, during recent years repeat cytological screening techniques are used to improve the efficiency of the cytological method. In particular, three new methods have been approved to improve the information content of Pap smears: computer screening of negative Pap smears, Pap test in solution and autocytology system. When performing a Pap test in solution, smears are taken using brushes and immediately placed in a special solution in a test tube, which is sent to the laboratory, where the smear is prepared. Before placing cells on a glass slide, the solution is shaken and filtered, i.e. One layer of epithelial cells is subjected to microscopy. An increase in the accuracy of cytological diagnostics when performing this technique is achieved by overcoming all the errors associated with the preparation of a smear.

The principle of the autocytological system is an automated computer differential diagnosis Pap smears. The scanned cells, which have undergone preliminary dispersion and centrifugation in order to separate blood and other components from them, are compared with standards stored in the computer memory for various morphological characteristics. As a result, the reliability of diagnosis significantly increases and the proportion of false negative results of cytological examination decreases.

When establishing a cytological diagnosis of CIN or cancer (Papanicolaou smear class 3–5 or high-grade PIP according to the Maryland system), an in-depth study is necessary - colposcopy and biopsy of the cervix with curettage of the mucous membrane of the cervical canal. In case of an inflammatory type of smear (Papanicolaou smear class 2, low-grade PIP, or the presence of unclassified atypical squamous epithelial cells according to the Maryland system), a repeat examination after sanitation is indicated, as well as HPV typing.

OPERATIONAL CHARACTERISTICS OF PAP smear

The method makes it possible to assess the structure and cellular level of damage to tissues caught in the smear. Cytological criteria are based on the severity of signs of cellular atypia, of which there are more than 80, but only 10 of them are the most constant.

The cytological method is highly reliable - an indicator of early cytological diagnosis of precancer and early stages RSM is approximately 80%. However, method errors, ranging from 5% to 40%, cover both harmless viral proliferation and genuine precursors of cancer. Negative cytological data do not exclude the presence of cervical microcarcinoma, therefore, each patient, when the pathological focus is localized on the vaginal part of the cervix, must undergo a targeted biopsy and curettage of the mucous membrane of the cervical canal.

FACTORS AFFECTING THE RESULT OF PAP smear

• Failure to comply with material collection techniques.
• Technical errors associated with the preparation of the drug.
• Qualification of pathologist.

ALTERNATIVE METHODS

A viable alternative to cytological screening for low- and middle-income countries economic development recognized screening test VIA (visual inspection with acetic acid - visual assessment of the condition of the ectocervix after treatment acetic acid) followed by immediate cryodestruction of identified pathological foci. To detect CIN II or more severe defeats cervix, the sensitivity of the VIA screening test is 71% and the specificity is 74%.