What is it?
Cancer of the uterine cervix (cervical cancer) is caused by an uncontrolled growth of cells in the cervix. The cervix is the narrowed lower portion of a woman’s uterus (womb). It is shaped like a cone and connects the uterus to the vagina. The uterine cervix is often referred to as the neck of the womb.
Since the introduction of the cervical screening programme in the UK, rates of cervical cancer have decreased. Cervical cancer is now the eleventh most common type of cancer in women in the UK and accounts for 2% of all new cancer cases in women. However, in developing nations without screening programmes cervical cancer is still a very serious health problem and cervical cancer continues to be the second most common type of cancer in women worldwide (after breast cancer).
Vaccination against HPV is available, but it will be many years before this reduces cervical cancer incidence further. Vaccination does not prevent all types of cervical cancer so vaccinated women are still advised to undergo regular screening.
Almost all (80-90%) of cervical cancers are squamous cell carcinomas. These occur in the flattened cells that cover the cervix, known as squamous cells. Most other cases are adenocarcinomas, rising from glandular cells of the upper cervix. A few cervical cancers are mixtures of both types.
Cervical cancer often has a pre-cancerous stage with abnormal changes in the cells of the cervix. These changes are termed “dyskaryosis” if detected on a liquid based cytology test (LBC) or cervical intraepithelial neoplasia (CIN) if detected on a biopsy. If left untreated, dyskaryosis or CIN may progress to cervical cancer. With early detection, cervical cancer is usually easily treatable.
Early detection and treatment can prevent cervical cancer, but the LBC screening test is not perfect and will not detect pre-cancerous states or cancer in all cases. If left untreated cervical cancer is almost always fatal. Given time, cervical cancer can spread to the rest of the uterus, bladder, rectum, and abdominal wall. It may involve the pelvic lymph nodes and may then spread (metastasise) to other organs throughout the body.
Human papillomavirus (HPV) (Wart virus) infection is the most important risk factor for cervical cancer. HPV is linked with around 95% of all cases of cervical cancer. HPV is a group of over 90 viruses that cause warts in a variety of places on the body, including the cervix. However, only some types are known to cause cervical cancer. The types that affect the cervix, vagina and vulva are usually spread sexually.
Types of HPV are divided into “high risk” and “low risk” categories based on their association with cervical cancer. HPV 16, 18, 31, and 33 are considered “high risk” because they have been linked with an increased risk for cervical, vaginal and vulval cancer. Other types such as HPV 6 and HPV 11 cause most cases of genital warts but are considered “low risk” because they rarely lead to cancer.
Women who have many sexual partners or women who started having sex at a young age are more likely to get cervical cancer. This is true because such activities increase the likelihood of picking up an infection with a “high risk” human papilloma virus (HPV). It is not correct to say that women who get cervical cancer have it because they were promiscuous (slept around). A woman could have only slept with one man and still caught the virus if he was infected. In addition, not all women with cervical cancer have HPV virus infection.
Weakening of the immune system through smoking, poor diet or other infections (including HIV/AIDS) may increase the risk of cervical cancer. Cigarette smoking suppresses the immune system and may damage the DNA in the cells of the cervix. Smokers are about twice as likely as non-smokers to get cervical cancer.
Precancerous changes in the cervix (CIN) usually do not cause any symptoms. By the time a woman notices symptoms, such as increased vaginal discharge and/or abnormal bleeding between menstrual periods or after intercourse, invasive cancer has usually developed and may have already spread to nearby tissues.
There are many conditions other than cancer that can cause abnormal vaginal bleeding and discharge. It is important to see your doctor for preventative screening and to determine the cause of any symptoms you may have.
Cervical screening tests are used to detect cancerous and precancerous changes in the cervix.
Liquid based cytology (LBC) test – (previously the Cervical smear test)
Cervical cells are collected for microscopic examination by a trained healthcare professional using a small brush, and the cells are placed into a pot of fluid. This test replaces the previous cervical smear test (the Papanicolaou (Pap) cervical smear) which used a wooden spatula to scrape cells off the cervix which were then spread onto a glass slide. This new LBC test is now widely used to screen for precancerous changes in cervical cells. It reduces the chances of an inadequate test and also allows the specimen to be tested for the presence of high risk HPV types.
Colposcopy – a follow-up test that may be advised if abnormal cells are found on an LBC test or if frequent inadequate LBC tests are obtained. Colposcopy is a simple examination that involves using a magnifying instrument to look closely at the cervix, checking for abnormal areas. At colposcopy, if abnormal looking areas are found on the cervix, small pieces of tissue (biopsies) will be removed for examination by a pathologist. A biopsy and microscopic (histopathology) examination is the only way to tell for sure whether abnormal cells are cancerous, precancerous, or look abnormal for some other reason.
If cancer is found, it will then be “staged.” Staging is a careful and thorough examination and classification of the extent of the disease (that is how far the cancer has spread and what body organs are involved). It includes an internal examination carried out under anaesthetic by a gynaecological oncologist (expert in cancer treatment) and radiological imaging such as CT or MRI scans.
Stages range from Stage 0 (precancerous stage) to Stage IVB (widespread metastatic cancer). Staging is a very important part of the diagnostic process; treatment options and patient outcomes depend in large part on the stage of the cancer.
Treatment of cervical cancer depends on the stage of the disease. If the cancer is either limited to the lining of the cervix or contained within the cervix, then the tissue containing the abnormal cells can usually be removed by a surgical operation.
More advanced cervical cancer may require surgery to remove the affected tissue and organs, followed by radiation treatments to destroy any remaining cancerous cells. If the cancer has spread to other sites (metastasised), intravenous cytotoxic chemotherapy may be required.
As methods of diagnosis, treatments, and therapeutic drugs are constantly evolving, if you have cervical cancer your gynaecological oncologist (expert in cancer treatment) will discuss treatment options and help choose a personalised treatment plan that is best for you.