- Category: Cancer/Malignancies
- Published on Sunday, 18 May 2014 00:00
- Written by Liz Highleyman
People with HIV -- especially those with light skin -- continue to have a significantly increased risk of developing melanoma in the era of highly effective antiretroviral therapy, and should protect themselves from the sun, according to a meta-analysis published in the April 16 edition of the open-access journal PLoS ONE.
AIDS-defining cancers such as Kaposi sarcoma have declined dramatically since the advent of combination highly active antiretroviral therapy (HAART), but people with HIV may still be at higher risk for various non-AIDS malignancies.
Catherine Olsen from QIMR Berghofer Medical Research Institute in Brisbane, Australia, and colleagues performed a systematic review and meta-analysis to evaluate the risk of melanoma among HIV positive people before and after the advent of HAART.
The study authors searched the Medline, Embase, and ISI Science Citation Index databases through April 2013, looking for cohort studies of people with HIV or AIDS that permitted quantitative assessment of the link with melanoma.
Out of 288 relevant articles, the researchers identified 21 that met the inclusion criteria. Among these, 8 reported pre-HAART data and 13 reported post-HAART data. A majority (12 studies) were done in the U.S., 8 in Europe, and 1 in Australia. About half included data about race/ethnicity, an important consideration because lighter skin color is a risk factor for melanoma. Median follow-up duration ranged from 2 to 10 years.
- In the pre-HAART studies, the pooled relative risk for the association between HIV/AIDS and melanoma was 1.26 overall -- or 26% increased risk -- rising to 1.28 in studies that adjusted for race/ethnicity.
- In the post-HAART studies, the pooled relative risk was again 1.26, an association with borderline statistical significance.
- In studies that accounted for race/ethnicity, relative risk rose to 1.50 -- a significant 50% increase.
- Results showed significant heterogeneity, or variability, between studies, but positive associations between HIV and melanoma risk were observed in most subgroups.
"People with HIV/AIDS remain at a significantly increased risk of developing melanoma in the post-HAART era," the researchers concluded.
The authors acknowledged that their review might have missed studies that showed no association between HIV and melanoma due to "publication bias," or the greater likelihood of publishing studies with interesting or positive results. On the other hand, the included studies may not have had a long enough follow-up period to capture development of melanoma over time, so the true association could be underestimated.
"The increased risk of melanoma in populations with HIV/AIDS may be related to effects of HIV infection on the immune system although these are complex, including not only immunodeficiency, but also chronic immune activation and inflammation, and immune dysfunction and senescence," they noted in their discussion.
There were not enough data on people diagnosed with AIDS -- indicating advanced immune suppression -- or on duration of HIV infection, CD4 count, or duration of ART to examine their influence in a multivariate analysis. However, one of the studies that stratified by CD4 count found that people with <200 or 200-500 cells/mm3 had a higher risk of melanoma, but not those with >500 cells/mm3.
The researchers also noted that people with HIV might be diagnosed with melanoma more often because they receive more regular medical care -- including surveillance for skin lesions -- or because white people with HIV/AIDS may have higher levels of recreational sun exposure.
"White skinned people with HIV/AIDS would benefit from regular screening of the skin for suspicious pigmented lesions, and since they also have a significantly increased risk of developing keratinocyte skin cancers (at least two-fold) they should be counseled to avoid excessive sun exposure," the authors recommended.
CM Olsen, LL Knight, AC Green, et al. Risk of Melanoma in People with HIV/AIDS in the Pre- and Post-HAART Eras: A Systematic Review and Meta-Analysis of Cohort Studies. PLoS ONE 9(6):e95096. April 16, 2014.