Cervical Cancer Screening
What is cervical cancer?
Cervical cancer begins in the cervix, the part of the uterus that opens to the vagina. Before doctors started using the Pap test in the 1950s, cervical cancer was the leading cause of death from cancer in women. In the United States, the Pap test saves the lives of 70% of the women who might have died from cervical cancer without the test. Recent advances in screening and work on a vaccine could help the effort to wipe out cervical cancer.
Every year, about 10,520 women in the United States get cervical cancer and about 3,900 women die from it. In other countries, cervical cancer affects approximately 500,000 women each year. In some parts of the world, it is still the most common cancer in women.
What causes cervical cancer?
The human papillomavirus, or HPV causes almost all cases of cervical cancer. HPV is a common sexually transmitted virus that usually goes away by itself. Most people with HPV never even know they have it.
There are two types of HPV—"low risk" and "high risk." Some low risk HPV infections can cause genital warts. Sometimes, if the high-risk type of HPV does not go away on its own, it may cause abnormal, or pre-cancerous, cells to form. If these abnormal cells are not found and treated, they may become cancer. In most women, the cells in the cervix return to normal after the body's immune system destroys the HPV infection.
What are the current cervical cancer screening guidelines?
The American Cancer Society (ACS) and the American College of Obstetricians and Gynecologists (ACOG) say that
- Women should be screened for cervical cancer about 3 years after they start having sexual intercourse.
- Screenings should start by the time a woman is 21 years old.
- Women should be screened every year with a regular Pap test. As an alternative, the newer liquid based Pap test can be used every year or every 2 years.
- All women 30 years old or younger should get cervical cytology (cancer) screening at least every two years.
- Some women age 30 and older who have had 3 normal Pap tests in a row don't need to get a Pap test every year. They can get the test every 2 or 3 years. Talk with your doctor about the best screening schedule for you. Even though women with normal results don't need to have a Pap test every year, they should go to their doctor every year for a check up, including a pelvic exam.
- According to ACS, women age 70 and older who have had 3 or more normal Pap test results in a row and no abnormal test in the last 10 years can stop having Pap tests. ACOG, however, recommends that women over the age of 70 should still get Pap tests every 2 or 3 years. Talk to your doctor to decide the best plan for you.
Do I need a Pap test if I've had a hysterectomy?
The answer to this question depends on why you had a hysterectomy.
- If you had a hysterectomy to treat cervical cancer, you should continue to have regular Pap tests to make sure the cancer hasn't come back.
- If you had a hysterectomy to treat pre-cancerous changes in your cervix you should continue to have regular tests for at least a few years after the surgery.
- If you had a hysterectomy to treat uterine or ovarian cancer, your doctor may advise you to have Pap tests regularly, since the tests are helpful in finding recurrences of these cancers.
- If you had a hysterectomy where your cervix was not removed (called a subtotal or supracervical hysterectomy), you should have regular tests until you are at least 70 years old. Since your cervix wasn't removed, there is still a chance you could develop cervical cancer.
- If you had a total hysterectomy (the entire uterus, including the cervix was removed) for a reason other than cancer or pre-cancer, you may not need to have the Pap or HPV test any more. Check with your doctor first, since some conditions may mean that you should continue to be tested.
- If you had a hysterectomy and are immunosuppressed (e.g. HIV, AIDS, transplant recipient), you may be more likely to develop problems from an HPV infection andyou should have a Pap test annually.
A Few Things to Remember
- The single most important thing that a woman can do is to participate in a regular screening program. All women who are screened have a dramatic reduction in the risk of cervical cancer compared to women who do not get tested.
- Most cervical cancer is preventable. Early detection of abnormal cell changes is important. Cervical cancer is rare and almost always prevented through regular screening and treatment of pre-cancerous changes.
- The new screening options including liquid-based Pap tests and the test for high-risk HPV are important developments for women and their physicians. In the future an HPV vaccine may prevent many Pap test abnormalities and most cervical cancer.