January is Cervical Cancer Awareness Month. Because of this, I would like to take this opportunity to provide education regarding cervical cancer risk factors and prevention for women. According to the American Cancer Society, there are several factors that put women at risk for cervical cancer.
The following are those risk factors:
Human Papilloma Virus (HPV) infection.
Weakened immune system.
Diet low in fruits and vegetables.
Oral contraceptives - long-term use.
Multiple full term pregnancies - three or more full term pregnancies increase the risk.
Young age at the first full term pregnancy - first full term pregnancy younger than 17 years increases the risk.
Diethylstilbestrol (DES) - DES is a hormone drug that was used between 1940 and 1971.
Family history of cervical cancer.
The cervix is the opening into the uterus or womb in a woman's body. The uterus is where a baby grows. Cervical cancer begins in the cells that line the cervix. The cell change that results in cancer is typically slow to develop. The normal cells of the cervix slowly change into pre-cancer cells that can eventually turn into cancer. These precancerous changes are known as dysplasia, cervical intraepithelial neoplasia (CIN) or squamous intraepithelial lesion (SIL). Of those cells that do progress, it usually takes at least three to seven years to become cancer.
Although there are several risk factors for cervical cancer, the highest risk factor is infection with the Human Papilloma Virus (HPV). HPV is not one single virus. There have been more than 100 different sero-types identified. Some types, having a higher risk of persistent infection progressing to cervical cancer, are considered high risk types. Sexually Transmitted Infections (STI) are commonly found in groupings. Chlamydia being the most commonly reported STI in the U.S. has also been found to be a risk factor for cervical cancer.
Smoking has been shown to increase the incidence of cervical cancer. Women who smoke are about twice as likely to get cervical cancer as those who do not. It may be due to damage to the DNA in the cervical cells by the carcinogens produced by smoking. Smoking also weakens the immune system making it more difficult to fight HPV infections.
The incidence of cervical cancer has decreased dramatically in the United States. This is primarily due to the development and widespread use of routine cytologic screening with the Pap smear. Pap test entails scraping cells from the cervical transformation zone and evaluating with a microscope. This allows detection of precancerous changes and the ability to implement therapy prior to progression to cancer. In the recent past, we have also had the ability to couple Pap tests with testing for high risk HPV types that pose a higher risk for persistent infection that can progress to cancer. Because we have been successful in convincing the majority of women in the United States to have an annual screening, the incidence of cervical cancer has fallen, while the diagnosis and treatment of precancerous changes has increased. In 1975 the incidence of cervical cancer was 14.4 per 100,000 women in the U.S.; by 2008 it had declined to 6.6. The American Cancer Society's estimate for 2012 was 12,170 new cases in the U.S. Currently, the majority of cancers are found in women who have never had a pap smear or had inadequate screening per the recommended guidelines.
Vaccinations for HPV have also been added, although the vaccine does not protect against all types of HPV. It is projected that significant benefit will not be achieved until approximately 20 years after extensive vaccination of a population has been initiated. By initiating extensive vaccination, future benefit is to be expected.
The most recent recommendations by the American Congress of Obstetricians and Gynecologists is to begin cervical cancer testing/screening at age 21. For women 21-29 years of age, testing should begin with a Pap test every three years. The ACOG recommends for women age 30-65 either a three-year screening with Pap smear alone or five-year testing with combined Pap smear and HPV screen. The latest recommendations from the ACOG indicate screening should be discontinued at age 65. However, women age 65 years and older do get cervical cancer. Women who have had a high grade precancerous change are advised to continue screening for 20 years even if this goes beyond age 65. Other high risk patients such as those with AIDs or HIV, prior DES exposure or other suppressed immune systems should have altered and more frequent screening.
Things to remember
The important things for women to remember regarding cervical cancer:
1. Lifestyle choices can make a difference in your risk of getting a cervical cancer.
2. Having screening pap smears, with or without HPV screening, can decrease your risk of cervical cancer.
3. There are false negative and false positive pap smears. Generally, long term pre-cancer changes with cervical cancer decreases the risk a lesion will be undetected if enough pap smears are done.
4. Screening recommendations do not take into consideration the fact, that most people extend the interval between recommended evaluations which increases the risk of undetected abnormality.
5. See your physician regularly. Your physician may alter your recommended testing based on your individual risks or previous experiences.
6. No testing is foolproof. Even with testing it is possible to develop a cervical cancer, but our national experience speaks to the benefit of implementing routine screening.
(Sources: American Cancer Society, American Congress of Obstetricians and Gynecologists, Centers for Disease Control and Prevention of the United States Department of Health and Human Services, Medical Institute for Sexual Health, Brian L. Welch, M.D., FACOG personal knowledge and experience)
Brian Welch, M.D., is board certified in obstetrics and gynecology. He is affiliated with Trimark OB/GYN and is on the staff of Trinity Regional Medical Center.