Cervical screening
THE CERVIX AND SCREENING
The lower part of the uterus is called the cervix.
Your doctor or nurse may need to see or touch the cervix during an exam.
The surface of the outside of the cervix is covered with flat cells called squamous cells. The cervical canal is full of column-shaped glandular cells that produce mucous. The place where these cells come together is known as the transformation zone. In this area, cells may develop abnormalities. These cells that line the cervix are the ones examined during cervical cancer screening.
WHAT IS CERVICAL SCREENING?
Cervical screening can detect changes in the cells of the cervix at an early stage. Early discovery of these changes may help prevent the development of cancer.
All women within a certain age span who have a registered GP can have cervical screening performed. Often, women are encouraged to be screened every three years.
During the test, your doctor or nurse takes a sample of the cells in your cervix. This procedure is known as liquid-based cytology or Pap smear. The cells obtained are later studied in a laboratory.
Regular screening is the best way to detect changes in the cells of the cervix at an early phase. At times, cellular changes may go unnoticed. In spite of this, cervical screening may prevent cancer in the majority of women.
Although the procedure is highly effective, patients should consult with their GP if any unusual symptoms show up. An example of such a symptom is bleeding after intercourse or between menstrual cycles. Screening is recommended even if you have never had sexual relations, with penetration or not.
PREPARING FOR THE TEST
Cervical screening detects changes in the cells of the cervix at an early phase. It is not a test for cancer, although the changes in these cells may lead to cancer in the future.
Detection is made possible by a test called liquid-based cytology. This test is also known as a Pap smear.
It is a simple procedure that takes less than five minutes. The doctor or nurse performing the procedure will gently place an instrument called speculum in your vagina. A small brush is then used to gently collect cells from the cervix. Some women find the procedure a bit uncormfortable, although it should not be painful.
It is best for the test not be performed during your period. It is also important to tell your doctor if you are pregnant. He or she may propose waiting until after you deliver.
Many women feel worried or ashamed of having a test of this nature. If you experience these feelings, it may be worthwhile to let your GP know. He or she may be able to calm you down.
RESULTS
Most women's results come back normal. Sometimes, a test may reveal that changes have taken place in the cells of the cervix. This does not mean that you have cancer. It means that some of your cells are abnormal and that you will require further testing.
Changes in cells are often caused by infection, inflammation, or certain medications you may be taking at the time.
Always let your doctor or nurse know if you are taking other types of medication.
Most abnormal results reveal minor changes in cells known as low-grade dyskaryosis. If this shows up on your report, the sample may be tested for human papillomavirus (HPV).
A small number of women have moderate or severe changes in these cells, known as high-grade dyskaryosis. If this happens, your GP will recommend further tests.
CERVICAL INTRAEPITHELIAL NEOPLASIA
Cervical intraepithelial neoplasia (CIN) occurs when there are changes on the surface of squamous cells in the cervix. It is not a type of cancer. However, having CIN increases women's chances of developing cervical cancer, which is why it is classified as a pre-cancerous condition.
Not all of the causes are known, although smoking may lead to increased risk. It is thought that the primary cause is infection by some types of HPV.
There is a vaccine that can protect women from two of the most common types of HPV. These vaccines do not work with all types of HPV, which is why it is important to have a cervical screening.
CINs do not always require treatment. However, if treatment is necessary, it is often successful.
Both HPV and CIN have no symptoms, which is why it is really important to have regular cervical screening performed in order to find possible changes to cells at an early phase.
Diagnosis
A colposcopy provides detailed images of the cervix using a specially adapted microscope called a colposcope. The colposcope acts as a magnifying class, allowing your health-care provider to clearly examine the entire cervix. A colposcopy is used to confirm whether you have a CIN—or, in rare cases, cancer—and the severity of the finding.
A specialist physician or nurse may perform a colposcopy. Before your exam, you will have a chance to talk to doctors or nursing staff about the results of your screening exam and discuss any worries you might have.
During the test, you will have to remain on a table or specially designed chair. An instrument called a speculum will be gently inserted in your vagina so that your vagina stays open for inspection of the cervix. Liquid coloring is used so that the abnormal areas clearly stand out. The colposcope, which remains outside your body, allows for a bright light to be seen from inside the cervix. A small sample (biopsy) may be taken of the cells. These cells will be examined under a laboratory microscope.
A colposcopy takes between 15 and 20 minutes. It is generally painless, although you may feel some pain if a biopsy is taken. The biopsy may also cause slight bleeding that lasts a couple of days.
Classification
CIN grading is based on how deep the cell changes penetrate the surface of the cervix:
- CIN 1 - when a third of the thickness of the surface layer of the cervix is affected.
- CIN 2 - when two thirds of the thickness of the surface layer of the cervix is affected.
- CIN 3 - when the entire thickness of the surface layer of the cervix is affected.
Knowing the CIN grade aids in planning the most optimal treatment.
Often only a small part of the cervix reveals abnormal changes.
CIN 3 is also known as carcinoma-in-situ. Although this may sound like cancer, CIN 3 is not cervical cancer. Cancer is developed when the deeper layers of the cervix are affected by abnormal cells. However, it's important that if CIN 3 is picked up during screening tests, plans are made to treat it as soon as possible.
Treatment
You may not need any treatment for CIN 1. This is because cells showing CIN 1 often return to normal. You may need to have more frequent screening tests to check for any further changes.
If you have CIN 2 or 3, your doctor may remove the abnormal cells.
There are different types of treatment.
Large loop excision of the transformation zone (LLETZ) is the most commonly used treatment. Usually, patients are given a local anesthetic. Once you are comfortable, the abnormal cells will be removed with a thin wire loop. The treatment takes about 5 to 10 minutes.
Some women have a cone biopsy. Normally, general anesthesia is given for this procedure. However, local anesthesia is used in some cases. Your doctor takes a small, cone-shaped piece of tissue from your cervix, which will be examined under a microscope.
Other treatments for CIN include the following:
- laser therapy
- cold coagulation
- cryotherapy
- hysterectomy (however, these are rarely needed for CIN).
Your doctor will explain which treatment is most suitable for you and what to expect before and after treatment.