Pap Smear Test: What Is It and When Should It Be Done?

Cervical cancer is a very common disease that causes the death of millions of women each year. Fortunately, the Pap smear test allows for early diagnosis and improves life expectancy.
Pap Smear Test: What Is It and When Should It Be Done?

Written by Luis Rodolfo Rojas Gonzalez, 30 May, 2021

Last update: 30 May, 2021

The female genitalia is a structure where many diseases can appear, and endanger a woman’s life. Because of this, there are gynecological tests that must be performed periodically, and one of these tests is the Pap smear test. But what is it and when is it necessary?

The cervix has different areas, such as the ectocervix located towards the vagina and an endocervix towards the interior of the uterus. Both have different cells, and, in this sense, cells of the ectocervix will be flat with multiple layers, while those of the endocervix will be cylindrical and mucosecretory.

Between the two epithelium, there’s an area called the squamo-columnar junction, which functions as a kind of transition zone. Cervical cancer appears more frequently in this area due to the low height of the cells. Therefore, the constant study of these structures is essential.

What is a Pap smear test?

The Pap test is very important.
This study is done to detect cervical cancer early.

Also known as cervical cytology, this is an exam that allows you to study the structure of the cells of the cervix, both the endocervix and the ectocervix. The main purpose of the Pap smear is to diagnose cervical cancer in women.

This test was developed by Dr. George Nicholas Papanicolau and has been used as a research method in the identification of cervical neoplasms since the 1950s. In fact, several studies claim that it’s one of the most important achievements when it comes to detecting diseases.

Cervical cells are deformed in the presence of cancer due to the denaturation of their proteins (when they lose their structure). In addition, the cell nucleus is affected by changes in DNA and increased cellular motility.

The Pap test can detect the presence of human papillomavirus (HPV) infections. Therefore, the test is useful to identify cellular changes that may turn into cancer in the future.

When is it necessary to have a Pap smear test?

First of all, it’s important to note that all women should have a gynecological check-up regularly to detect any abnormalities in time. Therefore, both breast self-examination for breast cancer prevention and timely medical check-ups with the gynecologist should be carried out.

One of the most important tests for a gynecological check-up is, as we’ve said, the Pap test. American Family Physician magazine recommends that all women over the age of 21 take this test. However, the frequency may vary depending on the patient’s age.

Women with no history of cancer between the ages of 21 and 65 should have this test at least every 3 years. However, women between the ages of 30 and 65 can have a Pap test every 5 years accompanied by an HPV test.

This medical examination doesn’t have major contraindications, but it isn’t recommended in women under 21 years of age due to the low incidence of cervical cancer at this age. In addition, neither should women over 65 with no history of cancer or hysterectomy be tested.

Preparation before the exam

The Pap test is a quick test that usually doesn’t require a lot of preparation. However, it’s important not to get tested during menstruation, as menstrual blood can make it difficult to see cervical cells.

On the other hand, experts recommend not to have sex or to apply vaginal douches in the 2 days before the exam. Spermicidal creams, foams, and gels are also contraindicated, because they can eliminate or hide abnormal cells.

It is advisable to wear comfortable clothes that aren’t too tight, so it’ll be easier and quicker to undress. Epilation (hair removal) isn’t necessary for the exam, do whatever makes you feel more comfortable in front of your doctor.

How is the Pap smear carried out?

This medical examination must always be performed at a gynecological appointment by qualified professionals. At the time of the exam, the doctor will ask you to remove your clothes from your lower body or take your clothes off completely, depending on the case. You should then lie down on the stretcher.

The Pap test is done in a medical position called a gynecological position or lithotomy. At this point, you should bend your knees and place your feet in a special area of the table called the stirrup. When in this position, the doctor will insert an instrument called a speculum into the vagina.

The speculum is an instrument that separates the vaginal walls and allows the observation of the cervix, the introduction of which is usually felt as a pressure in the region. After examining the cervix, the doctor inserts a special brush to remove the cells from the endocervix, and spreads these cells on a slide.

The endocervical cells must be removed afterwards and this is done with an instrument called a spatula. Sample collection generally doesn’t cause pain in patients. After removing the samples to be studied, the specialist will remove the speculum and the examination will be completed.

It’s possible to resume daily activities after the exam, and the patient doesn’t need to take any specific precautions in the following hours.

Analysis of the results

Pap smear
It’s always important to have the support of a gynecologist.

A Pap smear is negative when no abnormal cells are found, either in the endocervix or in the ectocervix. Women with a negative result don’t need to follow any specific care and must be examined again in 3 years.

On the other hand, a positive result is when abnormal cells are detected in any of the areas. Depending on the cells affected, some of the following may be found in the exam:

  • Atypical squamous cells of undetermined significance (ASC-US): In this case, there are abnormal cells in the ectocervix, although they’re not always precancerous. This result is usually due to the presence of HPV infection, and further studies are needed.
  • Scaly intraepithelial lesion: This result is a little more delicate and indicates the presence of abnormal cells that are precancerous. These cells can be low or high grade, which will determine how quickly they can progress to cervical cancer.
  • Atypical gland cells (AGC): An AGC indicates the presence of abnormal gland cells, that is, the endocervix. However, it still won’t be clear whether they’re pre-cancerous or not, and so further studies should be carried out to determine their origin.
  • Squamous cell carcinoma or adenocarcinoma: In some cases, the cells are so altered that the doctor can clearly diagnose the cancer. When this occurs, it’s necessary to quickly determine the extent of it to decide the best therapy to be followed.

A fundamental gynecological examination

The Pap test is one of the most important gynecological exams and should be performed periodically. It allows for early diagnosis of changes in the cervix and can prevent the development of cancer.

Despite its usefulness, this test can give false positives. Because of this, additional studies are always necessary in the presence of abnormal results. On the other hand, there may be false negatives, although their incidence is almost nil if the above recommendations are followed.

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