Research Links HPV Infection to Increased Risk for Skin Cancer

A research team led by the Cancer Center's Margaret Karagas, PhD, Professor of Epidemiology at Dartmouth Medical School, has found that people with several skin types of human papillomaviruses (HPVs) were more likely to develop certain skin cancers compared to people with no HPVs.

Focus article photo

Margaret Karagas, PhD

The population-based study, published by the British Medical Journal, also found that association between the HPVs and skin cancer was greater among people who took immunosuppression drugs.

The most common skin cancers (basal cell carcinoma and squamous cell carcinoma) are increasing globally. Ultraviolet radiation is the main established risk factor; however, HPV infection—of which there are more than 100 types—also may play a role in their development. Research has identified increased risks for people with skin HPV-types called beta HPVs. These skin type HPVs are different from the "high risk" mucosal type HPVs that cause cancer of the cervix and other anogenital cancers.

The Karagas research team, in collaboration with dermatologists, dermatopathologists, and pathologists throughout New Hampshire and bordering regions, studied 2,366 people living in New Hampshire. The group consisted of 663 people with squamous cell carcinoma, 898 people with basal cell carcinoma, and 805 healthy controls. In addition to interviewing the study participants, the researchers measured HPV antibodies in the blood samples from those people with basal cell and squamous cell carcinoma.

Results showed that people with squamous cell carcinoma, but not basal cell carcinoma, were more likely to have the beta HPV-types compared to people in the control group. The likelihood of having squamous cell carcinoma increased with the number of HPV-types people had. Patients with squamous cell carcinoma were 1.4 times more likely to have two to three types of HPV, and 1.7 times more likely to have greater than eight types of HPV, compared with the control group.

The researchers also found that people who used immunosuppressant drugs long term had more than a threefold risk of squamous cell carcinoma in relation to HPV, but a precision larger study is needed to confirm this.

"Given the widespread and growing occurrence of these malignancies, our results raise the possibility of reducing the health and economic burden of these cancers through prevention or treatment of human papillomavirus infection," says Dr. Karagas. "However, there is still much we need to understanding about these skin forms of HPVs and the biology of their behavior.

October 27, 2010