Skin cancer rates are higher among HIV-positive people than among the general population, according to data reported at the fourth IAS conference on HIV Treatment, Pathogenesis and Prevention (IAS 2007) in Sydney. The new findings suggest that skin cancer screening should be a component of routine HIV care, even for those with healthy immune systems.
Nancy Crum-Cianflone, MD, and her colleagues with the TriService AIDS Clinical Consortium in Bethesda, Maryland, explained that skin cancer is more common among patients with compromised immune systems, notably organ transplant recipients receiving immunosuppressive drugs.
While there has been no shortage of research showing that rates of Kaposi’s sarcoma (KS) have dropped sharply over the past 10 years due to the widespread use of antiretroviral (ARV) treatment, there has been little data regarding the incidence of non-AIDS skin cancers.
To explore rates of melanoma and both squamous cell and basal cell carcinomas, Dr. Crum-Cianflone’s group evaluated data from a cohort of 4,507 HIV-positive patients. Enrolled between 1987 and 2006, the participants had been followed for an average of 5.4 years.
The average age of the participants upon entering the study was 29 years. Forty-five percent of the patients enrolled were black; 44 percent were white.
The investigators report that 260 (5.8%) of the HIV-positive patients developed skin cancer while participating in the study. There were 201 cases of KS, 48 basal cell carcinomas, 13 melanomas (malignant) and 7 squamous cell carcinomas. Nine patients developed more than one type of skin cancer.
While KS was the most common form of skin cancer in the cohort, the researchers documented a significant drop in its incidence. After the introduction of combination therapy, the rate of KS declined to 180 per 100,000 person-years of follow up. Prior to ARV treatment advances, the rate had been 1,590 per 100,000 person-years of follow up.
Conversely, rates of non-AIDS skin cancers have remained the same since 1987. In the earlier years of the epidemic, melanoma and carcinoma rates were 300 per 100,000 person-years of follow up; since the late 1990s, rates have held relatively steady at 220 per 100,000 person-years of follow up.
Comparing these data to those mined from U.S. cancer registries, the authors reported a 2.3-fold increased risk for basal cell carcinoma among HIV-positive patients and a 3.1-fold increased risk for malignant melanoma.
The risk of squamous cell cancer was no higher among the HIV-positive patients than among the general population.
The greater risk of skin cancer was not associated with immune suppression. The average CD4 count at the time of cancer diagnosis was 432 cells, suggesting an increased risk even among those in earlier stages of HIV disease. Similarly, there were no associations between skin cancer risk and having either a high viral load or a history of human papillomavirus infection—a major cause of squamous cell cancer.
In summary, Dr. Crum-Cianflone’s group wrote that, in light of the significant increase in basal cell carcinoma and malignant melanoma, “Implementation of skin cancer screening should be considered given the aging HIV population.”
Source:
Crum-Cianflone N, Marconi V, Weintrob A, et al. Increased incidence of skin cancers among HIV-infected persons [Abstract MOPEB086]. Fourth International AIDS Society Conference on HIV Treatment, Pathogenesis and Prevention, Sydney, 2007.
