Smoking Associated with Increased Risk of Cervical Cancer in HPV-Infected Women
According to a recent article in the Journal of the National Cancer Institute, smoking increases the risk of developing cervical cancer in women infected with the human papillomavirus.
The cervix is a glandular organ that is located at the bottom of the uterus. Although rates of invasive cervical cancer have greatly declined with the use of screening with pap smears, researchers are evaluating variables which cause the initial development of cervical cancer. The human papillomavirus (HPV) is a sexually transmitted disease that is the primary cause of cervical cancer. HPV is present in virtually all cases of invasive cervical cancer. However, the majority of women infected with HPV do not develop cervical cancer. Previous data analysis has indicated that multiple births or oral contraceptive use may increase the risk of developing cervical cancer in women with HPV. However, further studies need to be conducted in order to verify this finding.
Researchers from Kaiser Permanente in Portland, Oregon and a division from the National Cancer Institute recently performed a clinical study involving over 1,800 women. At enrollment of the study, women had to test positive for HPV, but could not have any tumors on their cervix. The women filled out a survey regarding information such as the number of children they had, oral contraceptive use and smoking habits. These women were followed for 10 years.
The researchers discovered that smoking was correlated with a strong association in an increased risk of developing cervical cancer in these women. However, the number of children and oral contraceptive use did not appear to have a correlation in the development of cervical cancer. Former smokers and women who smoked less than one pack of cigarettes per day had three times the incidence of cervical cancer or a pre-cancerous condition, compared to women who never smoked. Women who smoked one or more packs per day had four times the incidence of cervical cancer or a pre-cancerous condition, compared to women who never smoked.
These researchers concluded that smoking increases the risk of developing cervical cancer in women who are infected with HPV. The authors caution that this group of women had a relatively low birth rate, so the association between an increasing number of births and the development of cervical cancer may not be appropriately addressed in this study. Women infected with HPV who smoke may wish to discuss the results of this study with their physician to determine their individual risk of developing cervical cancer.
Reference: Castle PE, Wacholder S, Lorincz AT, et al. A prospective study of high-grade cervical neoplasia risk among human papillomavirus-infected women.
Journal of the National Cancer Institute. 2002;94:1406-1414.