Definition
Cervical cancer is cancer that starts in the cervix ( the lower part of the uterus (womb) that opens at the top of the vagina).
Causes, incidence, and risk factors
Worldwide, cervical cancer is the third most common type of cancer in women.
Cervical cancers start in the cells on the surface of the cervix.
There are two types of cells on the cervix's surface: squamous and columnar. The majority of cervical cancers are from squamous cells.
The development of cervical cancer is very slow. It starts as a pre-cancerous condition called dysplasia. This pre-cancerous condition can be detected by a Pap smear and is 100% treatable. That is why it is so important for women to get regular Pap smears. Most women that are diagnosed with cervical cancer today have not had regular Pap smears or they have not followed up on abnormal results.
Undetected, pre-cancerous changes can develop into cervical cancer and spread to the bladder, intestines, lungs, and liver. It can take years for pre-cancerous changes to turn into cervical cancer. Patients with cervical cancer do not usually have problems until the cancer is advanced and has spread.
Almost all cervical cancers are caused by HPV (human papilloma virus). HPV is a common virus that is spread through sexual intercourse. There are many different types of HPV, and many do not cause problems. However, only certain strains of HPV actually lead to cervical cancer. (Other strains may cause genital warts.)
Other risk factors for cervical cancer include:
- Having sex at an early age
- Multiple sexual partners
- Sexual partners who have multiple partners or who participate in high-risk sexual activities
- Women whose mothers took the drug DES (diethylstilbestrol) during pregnancy in the early 1970s to prevent miscarriage
- Long-term use of birth control pills (more than 5 years)
- Weakened immune system
- Infections with genital herpes or chronic chlamydia infections
- Poor economic status (may not be able to afford regular Pap smears)
Symptoms
Most ot the time, early cervical cancer has no symptoms. Symptoms that may occur can include:
- Continuous vaginal discharge, which may be pale, watery, pink, brown, bloody, or foul-smelling
- Abnormal vaginal bleeding between periods, after intercourse, or after menopause
- Periods become heavier and last longer than usual
Symptoms of advanced cervical cancer may include:
- Loss of appetite
- Weight loss
- Fatigue
- Pelvic pain
- Back pain
- Leg pain
- Single swollen leg
- Heavy bleeding from the vagina
- Leaking of urine or feces from the vagina
- Bone fractures
Treatment
Treatment of cervical cancer depends on the stage of the cancer, the size and shape of the tumor, the age and general health of the woman, and her desire to have children in the future.
Early cervical cancer can be cured by removing or destroying the pre-cancerous or cancerous tissue. There are various surgical ways to do this without removing the uterus or damaging the cervix, so that a woman can still have children in the future.
Types of surgery for early cervical cancer include:
- LEEP (Loop Electrosurgical Excision Procedure) - uses electricity to remove abnormal tissue
- Cryotherapy - freezes abnormal cells
- Laser therapy - uses light to burn abnormal tissue
A hysterectomy (removal of the uterus but not the ovaries) is not often performed for cervical cancer that has not spread. It may be done in women who have repeated LEEP procedures. However, in more advanced disease, a radical hysterectomy may be performed. This type of hysterectomy removes the uterus and much of the surrounding tissues, including internal lymph nodes and upper part of the vagina. In the most extreme surgery, called a pelvic exenteration, all of the organs of the pelvis, including the bladder and rectum, are removed.
Radiation may be used to treat cancer that has spread beyond the pelvis, or cancer that has returned. Radiation therapy is either external or internal. Internal radiation therapy uses a device filled with radioactive material, which is placed inside the woman's vagina next to the cervical cancer. The device is removed when she goes home. External radiation therapy beams radiation from a large machine onto the body where the cancer is located. It is similar to an x-ray.
Chemotherapy uses drugs to kill cancer. Some of the drugs used for chemotherapy for cervical cancer include 5-FU, Cisplatin, Carboplatin, Ifosfamide, Paclitaxel, and Cyclophosphamide. Sometimes radiation and chemotherapy are used before or after surgery.
Expectations (prognosis)
Many factors influence the outcome of cervical cancer. These include:
- The type of cancer
- The stage of the disease
- The age and general physical condition of the woman
Pre-cancer conditions are completely curable when followed up and treated properly. The chance of being alive in 5 years (5-year survival rate) for cancer that has spread to the inside of the cervix walls but not outside the cervix area is 92%.
However, the 5-year survival rate falls steadily as the cancer spreads into other areas.
Complications
- Some types of cervical cancer do not respond well to treatment.
- The cancer may come back (recur) after treatment.
- Women who have treatment to save the uterus have a high risk of the cancer coming back (recurrence).
- Surgery and radiation can cause problems with sexual, bowel, and bladder function.
Prevention
A new vaccine to prevent cervical cancer is now available. In June 2006, the U.S. Food and Drug Administration approved the vaccine called Gardasil, which prevents infection against the two types of HPV responsible for the majority of cervical cancer cases. Studies have shown that the vaccine appears to prevent early-stage cervical cancer and precancerous lesions. Gardasil is the first approved vaccine targeted specifically to prevent any type of cancer.
Practicing safe sex (using condoms) also reduces your risk of HPV and other sexually-transmitted diseases. HPV infection causes genital warts. These may be barely visible or several inches wide. If a woman sees warts on her partner's genitals, she should avoid intercourse with that person.
To further reduce the risk of cervical cancer, women should limit their number of sexual partners and avoid partners who participate in high-risk sexual activities.
Getting regular Pap smears can help detect pre-cancerous changes, which can be treated before they turn into cervical cancer. Pap smears work very well in spotting such changes, but they must be done regularly. Annual pelvic examinations, including a pap smear, should start when a woman becomes sexually active, or by the age of 20 in a non-sexually active woman. If abnormal changes are seen, a colposcopy with biopsy should be performed.
If you smoke, quit. Cigarette smoking is associated with an increased risk of cervical cancer.
References
Lowy DR, Schiller JT. Prophylactic human papillomavirus vaccines. J Clin Invest. 2006 May;116(5):1167-73.
Villa LL, Ault KA, Giuliano AR, et al. Immunologic responses following administration of a vaccine targeting human papillomavirus Types 6, 11, 16, and 18. Vaccine. 2006 May 15 [Epub ahead of print].
US Food and Drug Administration. FDA Licenses New Vaccine for Prevention of Cervical Cancer and Other Diseases in Females Caused by Human Papillomavirus. Rockville, MD: National Press Office; June 8, 2006. P06-77.
Source : http://www.healthline.com
