Cervical Cancer

Overview

The cervix is the lower part of the uterus. Each year in the United States, an estimated 12,000 women are diagnosed with cancer of the cervix.[1]

Most cervical cancers are linked to infections with high-risk types of human papillomavirus (HPV). Vaccines are now available to prevent infection with certain types of HPV, and are most effective when administered before a woman becomes sexually active.

Cancerous and precancerous changes to the cervix may first be detected through a pelvic exam or Pap test. Identification and management of precancerous changes to the cervix may prevent the development of invasive cervical cancer.

If cervical cancer or precancer is suspected, a physician may use a colposcope (lighted microscope) to better visualize the cervix, and may perform a biopsy to remove a sample of tissue for further evaluation.

Prevention and Screening

The chance of an individual developing cancer depends on both genetic and non-genetic factors. A genetic factor is an inherited, unchangeable trait, whereas a non-genetic factor is a variable in a person’s environment, which can often be changed. Non-genetic factors may include diet, exercise, or exposure to other substances present in our surroundings.

Hereditary or Genetic Factors

At this time, researchers have not identified hereditary factors that contribute to the development of cervical cancer.

Environmental or Non-Genetic Factors

HPV infection: Most cases of cervical cancer are caused by infection with a high-risk type of humanpapillomavirus (HPV). HPV types 16 and 18 are thought to account for roughly 70 percent of all cervical cancers, but several other high-risk types of HPV contribute to cervical cancer as well. The types of HPV that cause genital infections are transmitted sexually and are extremely common. Many infections resolve on their own, but some persist and lead to precancer or cancer of the cervix, vulva, vagina, penis, and anus. HPV also contributes to some cases of head and neck cancer.

Human Immunodeficiency Virus (HIV): Infection with HIV-1 or HIV-2 may contribute to the development of cervical cancer by suppressing the immune system.

Cigarette smoking: Cigarette smoking is consistently linked with an increased risk of developing cervical cancer. The link between smoking and cervical cancer may be explained at least in part by increased persistence of high-risk HPV infections in women who smoke.[2]

Prevention

HPV vaccine: The use of vaccines that prevent infection with two high-risk types of HPV is expected to substantially reduce the occurrence of cervical cancer. Gardasil® and Cervarix® both protect against HPV types 16 and 18. Gardasil also protects against HPV types 6 and 11, which account for most cases of genital warts. Use of these vaccines has the potential to eliminate most (but not all) cases of cervical cancer. Women who are vaccinated should continue to be screened for cervical cancer. It is important to note that these vaccines are intended to prevent infection with HPV; the vaccines do not treat existing infections or cervical cancer. Because infection with HPV is very common and often occurs soon after an individual becomes sexually active, vaccination is likely to have the greatest effect when administered before a girl becomes sexually active.

Condom use: Because vaccination does not protect against all high-risk types of HPV, supplementing use of the vaccine with other approaches to HPV prevention is important. Consistent use of condoms may reduce the risk of HPV infection.[3]

Detection and Treatment of Precancerous Changes to the Cervix: Cervical cancer is thought to be preceded by precancerous changes to the cervix. Detection and treatment of these changes can prevent the development of invasive cervical cancer. Regular cervical cancer screening (discussed below) offers the best approach to early detection.

Screening and Early Detection

For several types of cancer, progress in the area of cancer screening has led to earlier cancer detection and better outcomes. The term screening refers to the regular use of certain examinations or tests in persons who do not have any symptoms of a cancer but are at risk for that cancer.

The American Cancer Society recommends that cervical cancer screening begin about three years after a woman begins having vaginal intercourse, but no later than the age of 21.[4]

Papanicolaou (Pap) test: Routine screening with a Pap test is used to detect abnormal cells on the cervix. During a Pap test, a sample of cells from the cervix is taken with a small wooden spatula or brush and examined under the microscope.

If the Pap test identifies abnormal cells, women may undergo a colposcopy for further evaluation.[5] During a colposcopy, a physician uses a microscope called a colposcope to better see the cervix. If abnormal areas are identified, the physician may perform a biopsy (remove a sample of tissue for additional evaluation). The results of the biopsy allow the physician to diagnose cancer or precancerous conditions.

HPV Testing: The recognition that certain types of HPV can cause cervical cancer led to the development of a test to identify women infected with high-risk types of HPV. One use for HPV testing is further evaluation of women with an indeterminate Pap test result. HPV testing may also be combined with Pap testing during initial cervical cancer screening, but this is not recommended for young women (those under 30) because many young women have HPV infections that will clear without causing serious cervical abnormalities.[6]

Learn More

In order to learn more about the most recent information available concerning the treatment of cervical cancer, click on the appropriate stage.

Precancerous Changes to the Cervix: Cervical abnormalities that may progress to invasive cervical cancer if left untreated.

Stage I: Cancer has not spread beyond the uterus.

Stage II: Cancer involves the tissues surrounding the cervix (parametria) or the upper portion of the vagina, but has not spread to the lymph nodes.

Stage III: Cancer has spread to the lower vagina or sides of the pelvis, causes a blockage of drainage from the kidney, and/or involves nearby lymph nodes.

Stage IV: Cancer invades the bladder or rectum or has spread outside of the pelvis.

Recurrent/Relapsed: Cervical cancer is still detected or has returned (recurred/relapsed) following an initial treatment with surgery, radiation therapy, and/or chemotherapy.

References:


[1] American Cancer Society. Cancer Facts and Figures 2010.

[2] Koshiol J, Schroeder J, Jamieson DJ et al. Smoking and Time to Clearance of Human Papillomavirus Infection in HIV-Seropositive and HIV-Seronegative Women. American Journal of Epidemiology. 2006;164:176-183

[3] Winer RL, Hughes JP, Feng Q et al. Condom Use and the Risk of Genital Human Papillomavirus Infection in Young Women. New England Journal of Medicine. 2006;354:2645-54.

[4] American Cancer Society. American Cancer Society Guidelines for the Early Detection of Cancer. Accessed June 25, 2010.

[5] Wright Jr. TC, Massad S, Dunton CJ et al. 2006 consensus guidelines for the management of women with abnormal cervical cancer screening tests. American Journal of Obstetrics and Gynecology. 2007;346-355.

[6] Wright Jr. TC, Massad S, Dunton CJ et al. 2006 consensus guidelines for the management of women with abnormal cervical cancer screening tests. American Journal of Obstetrics and Gynecology. 2007;346-355.