Cancer in Lesbian, Gay, and Bisexual People

SUMMARY Gay men are nearly twice as likely to report cancer than heterosexual or bisexual men, according to a large survey of California residents, while lesbian and bisexual women had higher rates of uterine and cervical cancer, respectively.

By Matt Sharp

Lesbian, gay, and bisexual (LGB) people are often at risk for cancer due to lifestyle factors, cultural issues, HIV disease, and other factors. But it has been a challenge to ascertain whether cancer rates and outcomes differ in these populations compared to heterosexuals, as data on sexual orientation is not typically collected through standard methods.

A new analysis published in the May 9, 2011, advance online edition of the American Cancer Society's journal Cancer provides some compelling information on the question of cancer prevalence among lesbian, gay, and bisexual people in California. (The analysis did not specifically assess transgender people or the influence of gender identity.)

The study looked at more than 120,000 adults (age 18-70 years) who took part in the California Health Survey in 2001, 2003, and 2005. This household-based survey asked about participants' sexual orientation and if they had ever been diagnosed with cancer. If participants had been diagnosed with a malignancy, they were asked to give other details about their diagnosis and health status.

The investigators then used logistic regression to analyze cancer prevalence in men and women, as well as self-reported health of male and female cancer survivors -- defined by the authors as people "living with, through, and beyond a diagnosis of cancer" -- by sexual orientation.

Cancer in Men

The results showed that overall cancer rates for gay men were almost twice as high as for heterosexual and bisexual men (8% vs 5%, respectively). "Bisexual men were mostly similar to heterosexual men," with respect to cancer rates and self-reported health, the authors wrote.

Of the 51,233 men in the study, 3690 said they had been diagnosed with cancer, and the rate was significantly higher among gay men compared to bisexual or heterosexual men. Gay men surveyed were also approximately 10 years younger than bisexual or heterosexual men at the time of cancer diagnosis. (41 vs 50 vs 51 years, respectively).

Unfortunately the California Health Survey did not collect information about HIV status. People with HIV have higher rates of AIDS-related cancers including Kaposi sarcoma and non-Hodgkin lymphoma, as well as some non-AIDS cancers such as anal, lung, and testicular cancer. The authors acknowledged this weakness in their study.

The higher cancer rate among gay men may have been due in part to greater prevalence of anal cancer, which is known to be greater among men who have sex with men and especially among HIV positive gay men. However, prostate cancer was reported less often by gay men (about one-third the prevalence of other men), consistent with past research showing lower prostate cancer rates among men with HIV.

Cancer in Women

Out of 71,112 women surveyed 7252 said that they had been diagnosed with cancer. Cancer prevalence ranged from 6% to 9% for women, but unlike men, overall prevalence did not differ according to sexual orientation.

Looking at individual cancers, the investigators found that lesbians were more likely to have had uterine cancer. Bisexual women were least likely to report uterine cancer, but were more than twice as likely to report cervical cancer than other groups, which was highly statistically significant. Rates of breast cancer did not differ according to sexual orientation in this analysis.

Outcomes and Recommendations

Among women cancer survivors, lesbians and bisexual women tended to be more likely than heterosexual women to report fair or poor health. Among men, in contrast, there were no differences by sexual orientation in cancer survivors' self?reported health.

People in the LGBT community are most certainly aware of higher prevalence of cancer among their peers. Yet this study provides more detailed information that can be used to help set priorities for cancer programs for this population, including screening, prevention, and other services.

"Specifically for men, the greatest need is for interventions that target cancer prevention in gay men, given the disparity by sexual orientation in cancer prevalence," the study authors recommended. "Our study indicates for women the greatest need is for interventions that target lesbian and bisexual cancer survivors to improve their health perceptions."

"Given the existence of a screening test for cervical cancer, the Papanicolaou [Pap] test, our findings suggest a need to target bisexual women with screening interventions to reduce the prevalence of cervical cancer in this population," they added.

Investigator affiliations: Department of Community Health Sciences, Boston University School of Public Health, Boston, MA; Department of Biostatistics, Boston University School of Public Health, Boston, MA.

6/14/11

Reference
U Boehmer, X Miao, and A Ozonoff. Cancer, survivorship and sexual orientation. Cancer (abstract). May 9, 2011 (Epub ahead of print).