A recent Danish study published in the Journal of the American Academy of Dermatology found that overall, people with HIV had an increased risk of developing certain types of skin cancer. The three types of cancers that affect the skin are:
Basal cell carcinoma (BCC): the most common form of skin cancer, mainly caused by excess exposure to the sun or other ultraviolet light sources and most common in fair-skinned people. These cancers start in the lower level of the skin.
Squamous cell carcinoma (SCC): similar to BCC but starting in the upper layer of the skin.
Malignant melanoma (MM): a less common but more aggressive type of skin cancer, caused by sun exposure and ultraviolet light.
In the study, researchers found that people living with HIV were twice as likely to develop BCC, and five times as likely to develop SCC. The investigators compared the risk factors of the three types of skin cancer between HIV-positive people enrolled in the cohort study (4,280 participants) to that of the general Danish population (21,399 controls). To factor in sun exposure from childhood, the authors also examined cancer incidence in the siblings of participants from both arms of the study.
“This unique study design using high-quality, population-based nationwide data enabled us to address potential confounding by skin type and family-related sun behavior, and to provide data on skin cancer risk in HIV-infected patients from more northern parts of the world,” said researchers in a report by NAM AIDSmap.
“The increased risk of BCC was restricted to patients reporting MSM [men who have sex with men] as route of HIV. There seemed to be an association between immunosuppression and SCC-risk for [HIV-positive] patients. The risk of MM was not increased when compared with the background population, but [the] low number of MM cases makes definitive conclusion difficult.”
Fortunately, due to the treatment advancements made with antiretroviral therapy, not only are people with HIV living long healthy lives these days, their rates of AIDS-related cancers (i.e. Kaposi Sarcoma and non-Hodgkin lymphoma) have dramatically declined since the 1990s. Unfortunately, rates of other malignancies not traditionally associated with HIV-related conditions are increasing.
Despite these findings, it’s unclear if HIV itself is associated with an increased risk of skin cancer. The main cause of skin cancer is sun exposure or ultraviolet light, but immunosuppression may also increase the risk.
“One could argue that the increased risk of BCC might be driven primarily by sun exposure or sunbed use in youth/adulthood not accounted for by the sibling model since previous data suggest that [HIV-positive] MSM might have increased recreational UV-exposure,” suggest the authors.
BCC and SCC are usually treated by surgery and the prognosis after treatment of these cancers is very good. MM is also treated by surgery, which is usually successful if the cancer is spotted at an early stage, NAM AIDSmap reports.
“With this nation-wide, population-based cohort study, we have demonstrated that [HIV-positive] patients have an increased risk of BCC and SCC,” conclude the authors. “The risk of SCC seemed to increase with increasing level of immunosuppression while the increased risk of BCC was restricted to patients reporting MSM as route of [contraction].”