Cervical Cancer

Worldwide, cervical cancer is the second most common cancer in women. In the United States, the incidence of cervical cancer has steadily declined over the last few decades, largely because of the widespread use of Pap smears. Still, the American Cancer Society estimates that more than 11,000 cases of cervical cancer will be diagnosed in the United States in 2007.    

Causes

Several factors increase your risk for cervical cancer by increasing your risk of exposure to the human papillomavirus (HPV). HPV is now believed to be the cause of almost all cervical cancer; HPV types 16 and 18 are the strains that cause most of the cancer cases. Other types of HPV cause genital warts and common warts on other parts of the body. Research suggests that often two of the following factors are present when cervical cancer develops:

• You have had sex with many partners.

• You became sexually active before you were 18.

• You smoke.

• Your immune system is weakened, such as in women who have human immunodeficiency virus (HIV) or are on medications to suppress their immune system after a transplant.

Symptoms

Cervical cancer is generally detected early, with a Pap smear, when there are no symptoms. Symptoms can include:

• Abnormal vaginal bleeding after intercourse

• Pain or discomfort in the vagina

• Odorous discharge from the vagina

• Pain with urinating.

Prevention

A vaccine is now available to prevent infection with HPV, a major cause of cervical cancer. The vaccine protects against HPV strains 16 and 18, which cause about 70 percent of cervical cancers, and against types 6 and 11, which cause about 90 percent of genital warts. The vaccine does not protect against HPV strains 31 or 45, which can also cause cervical cancer. The vaccine is approved for females ages 9 to 26 and for women who have Pap smear abnormalities.

The vaccine is given in three doses over six months. If a woman is already infected with one of the HPV strains 16, 18, 6 or 11, the vaccine cannot protect her from the effects of that strain. (It will protect her against the three other strains, however.) The vaccine also will not protect against infection with other HPV strains, so regular Pap tests are still important.

Because the vaccine is new, experts don't know how long it will continue to offer protection. Studies so far, however, have shown that the vaccine continues to be effective against HPV 16 for four years.

Although the vaccine is not routinely recommended for females older than 26 or for males, another vaccine is currently being tested for use in boys and young men.

Method for Detecting Cervical Cancer

A Papanicolaou (Pap) smear is a simple procedure for women that involves swabbing a small sample of cells from the cervix during a pelvic exam. These cells are transferred to a slide and then examined and evaluated by a certified laboratory. In addition to testing for cancerous or precancerous conditions, the Pap smear is also useful for detecting some types of infections.

If the Pap test result is mildly abnormal -- containing atypical squamous cells (ASC) -- another test may be done to determine if there is an infection with a high-risk type of HPV. If this test shows a high-risk HPV infection, a colposcopy -- an examination of the cervix with a special instrument that magnifies the cells -- may be done.

Cervical cancer screening should begin approximately three years after a woman begins having vaginal intercourse, but no later than 21 years of age. Screening should be done every year with conventional Pap tests or every two years using liquid-based Pap tests.  At or after age 30, women who have had three normal test results in a row may get screened every two to three years. Women 70 years of age and older who have had three or more normal Pap tests and no abnormal Pap tests in the last 10 years, and women who have had a total hysterectomy, may choose to stop cervical cancer screening.

More frequent Pap smears are recommended for women who have had an abnormal Pap smear in the past five years or who are HIV positive. Women with HIV infection may need more frequent Pap smears as their disease progresses.

To ensure the most accurate test results with your Pap smear, avoid using a vaginal douche or any type of lubricant for 24 hours before having a Pap smear. If you have used either, tell your doctor before the procedure.

Regular Pap smear screening makes it possible to find early evidence of cancer, when the disease is easier to cure. When diagnosed early, cervical cancer can be cured in almost all cases.