The cervix is the lower, narrow part of the uterus (womb) located between the bladder and the rectum. It forms a canal that opens into the vagina, which leads to the outside of the body.
Precancerous conditions of the cervix are identified as cells that appear to be abnormal, but are not cancerous at the present time. However, the appearance of these abnormal cells may be the first evidence of cancer that develops years later.
Precancerous changes of the cervix usually do not cause pain and, in general, do not cause any symptoms. They are detected with a pelvic exam or a Pap test.
Squamous intraepithelial lesions (SIL) is aterm that refers to abnormal changes in the cells on the surface of the cervix.
According to the National Cancer Institute (NCI), changes in these cells can be divided into two categories:
Low-grade SIL refers to early changes in the size, shape, and number of cells that form the surface of the cervix. They may go away on their own, or, with time, may grow larger or become more abnormal, forming a high-grade lesion. These precancerous low-grade lesions may also be called mild dysplasia or cervical intraepithelial neoplasia 1 (CIN 1). These early changes most often occur in women between the ages of 25 and 35, but can appear at any age.
High-grade SIL means there are a large number of precancerous cells, and, like low-grade SIL, these precancerous changes involve only cells on the surface of the cervix. The cells often do not become cancerous for many months, perhaps years. High-grade lesions may also be called moderate or severe dysplasia, CIN 2 or 3, or carcinoma in situ. They develop most often in women between the ages of 30 and 40, but can occur at any age.
If abnormal cells on the surface of the cervix spread deeper into the cervix, or to other tissues or organs, the disease is then called cervical cancer, or invasive cervical cancer. Cervical cancer occurs most often in women over the age of 40. It is different from cancer that begins in other parts of the uterus and requires different treatment. Most cervical cancers are squamous cell carcinomas and adenocarcinomas.
The mortality rates for cervical cancer have declined sharply as Pap screenings have become more prevalent. About 12,900 cases of invasive cervical cancer will be diagnosed in the US during 2001. Some researchers estimate that noninvasive cervical cancer (also referred to as "carcinoma in situ") is nearly four times more common than invasive cervical cancer.
The following have been suggested as risk factors for cervical cancer:
Chlamydia and Cervical Cancer
New research has shown that chlamydia, the most common sexually transmitted disease in the US, may increase a woman's risk of developing cervical cancer. In the study, published in the Journal of the American Medical Association (JAMA), women who showed signs of any type of chlamydial infection in their blood were two-and-a-half times more likely to develop cervical cancer, when compared to women with no sign of infection. Although the reason for this increased risk is still under investigation, researchers speculate that immune system cells that are activated at chlamydia infection sites may damage normal cells.
Early detection of cervical problems is the best way to prevent cervical cancer. Routine, annual pelvic examinations and Pap tests can detect precancerous conditions that often can be treated before cancer develops. Invasive cancer that does occur would likely be found at an earlier stage. Pelvic examinations and Pap tests are the methods used to determine if there are cervical problems. Women who are or have been sexually active, or are age 18 or older, should have regular checkups, including a pelvic exam and Pap test.
According to the National Institutes of Health (NIH):
A pelvic exam and Pap test allow the physician to detect abnormal changes in the cervix. If an infection is present, it is treated and the Pap test is repeated at a later time. If the exam or Pap test suggests something other than an infection, a repeated Pap test and other tests are performed to determine the problem.
Women who have had a hysterectomy (surgery to remove the uterus, including the cervix) should ask their physician's advice about having pelvic exams and Pap tests.
Symptoms of cervical cancer usually do not appear until abnormal cervical cells become cancerous and invade nearby tissue.
The symptoms of cervical cancer may resemble other conditions or medical problems. Consult a physician for diagnosis.
When cervical problems are found during a pelvic examination, or abnormal cells are found through a Pap test, a cervical biopsy may be performed.
There are several types of cervical biopsies that may be used to diagnose cervical cancer, and some of these procedures that can completely remove areas of abnormal tissue may also be used for treatment of precancerous lesions. Some biopsy procedures only require local anesthesia, while others require a general anesthesia. Several types of cervical biopsies include:
Specific treatment for cervical cancer will be determined by your physician based on:
Treatment may include:
LEEP or conization may also be used to remove abnormal tissue.