The most common sexually transmitted disease in the U.S., chlamydia, may increase the risk of developing cervical cancer, according to a recent study published in The
Journal of the American Medical Association (
Cervical cancer is one of the more preventable types of cancer. There are a number of risk factors that can increase the risk of developing cervical cancer, such as smoking, a poor diet, HIV infection and failure to undergo regular screening. The most important risk factor is infection with a sexually transmitted disease called the human papillomavirus (HPV). Scientists have long known that HPV infection is a step in the development of almost all cervical cancers; however, they have also believed that there must be other factors, as the majority of women with HPV do not develop cervical cancer.
During this recent study, researchers analyzed blood samples from 128 women with invasive cervical cancer and 533 women who did not have cervical cancer and then directly compared the two groups. Women with any type of chlamydia infection were approximately 2.5 times more likely to develop cervical cancer, compared with women who had no evidence of chlamydia infection. Moreover, women with a particular subtype of chlamydia, serotype G, were 6 times more likely to develop cervical cancer.
The researchers in this study are unsure exactly how chlamydia increases cervical cancer risk. They speculate that perhaps immune system cells active at the site of chlamydia infections could be damaging normal cells and causing them to turn cancerous. Further research in larger groups is needed to confirm the results of this study and determine exactly how chlamydia contributes to cervical cancer risk.
The two best ways to reduce the risk of developing cervical cancer are to avoid the risk factors and to have an annual Pap smear. Routine screening with a Pap smear is used to detect cancerous cells in the cervix
early as well as to detect abnormal cells in the cervix before they become cancerous. A Pap smear consists of the removal of cells from the cervix and examination of these cells under a microscope.
The results of this study also suggest that screening for chlamydia infection may play a crucial role in the future for reducing the risk of cervical cancer, however more research is needed to determine the extent of this risk. (
JAMA, Vol 285, No 1, 2001)