Cancer survivorship and sexual orientation

Abstract

Boehmer et al1 used California Health Interview Survey (CHIS) data to compare self-reported cancer survivorship among heterosexual, homosexual, and bisexual Californians. Among 29 cancer types covered, but not separately reported, was nonmelanoma skin cancer (NMSC), the most common of all cancers.2 NMSC is characterized by its higher incidence in whites and its low case fatality rate. Consequently, major differences in the ethnic composition of heterosexual (50% whites) and homosexual (67% whites) men suggest that NMSCs may have contributed significantly to the doubled rate of cancer survivorship in gay men. Unfortunately, most of the 29 cancer types, including NMSC, were lumped together as “other cancer.” This category should have been broken down in meaningful categories for readers to judge the extent to which the increased self-reported cancer survivorship in gay men was due to prior NMSCs, aquired immunodeficiency syndrome (AIDS)-associated cancers (Kaposi sarcoma, non-Hodgkin lymphoma),3 or tobacco- or alcohol-related cancers. Overall, 8.25% of homosexual men and 5.04% of heterosexual men reported a prior cancer (odds ratio [OR], 1.9; 95% confidence interval [CI], 1.5-2.5). The authors are encouraged to present corresponding prevalence estimates in homosexual and heterosexual men and ORs with 95% CI for 1) all cancers excluding NMSCs to partly account for the skewed ethnic composition of the studied groups of heterosexual and homosexual men, and 2) all cancers excluding AIDS-associated cancers to learn to what extent gay men with AIDS accounted for the observed excess of prior cancers. The authors mention that men tend to underreport prior cancers more than women. If gay men resemble women more than heterosexual men in this regard, such reporting bias may well explain the apparent higher rate of cancer survivorship in gay compared with heterosexual men. Boehmer et al1 acknowledge that cautious interpretation of their findings is warranted because survivorship and incidence are 2 completely different things. Unfortunately, however, among the unsupported messages from this study that have already spread in the news media in Europe, is that gay men are at a double risk of getting (not of having had) a cancer diagnosis, and at a much younger age, than heterosexual men. Carefully designed and properly controlled prospective studies are urgently needed to qualify this message. So far, only 1 population-based study has evaluated the prospective cancer risk in gay men and lesbians. Among 5000 Danish persons in same-sex partnerships, there was no evidence of an increased cancer incidence, except among gay men with AIDS.4 The authors made no disclosures Morten Frisch MD, PhD, DSc(Med)*, * Department of Epidemiology Research, Statens Serum Institut, DK-2300 Copenhagen S, Denmark.