Ethnic Disparities in Cancer Reflect Disparities in HIV Care

While several cancers associated with immunosuppression are much more common in White men who have sex with men living with HIV (MSMWH) than in the male general population, they are even more frequently seen in Black and Hispanic MSMWH. 

This suggests that racial and ethnic disparities in access to antiretroviral therapy and viral suppression are playing a role, said the authors of an analysis published last month in AIDS. 

“Disparities in cancer risk may serve as an important proxy for disparities in HIV care,” they wrote.

The researchers at the National Cancer Institute leveraged data from the HIV/AIDS Cancer Match Study, which covers 13 US states and the District of Columbia. For this analysis, they examined cancer incidence in over 350,000 MSMWH followed for 3.2 million person years, between 2001 and 2019.

They focused on Kaposi sarcoma, non-Hodgkin lymphoma, Hodgkin lymphoma, anal cancer, and liver cancer — all malignancies that are associated with viral infections and immunosuppression. They restricted their analysis to MSM because behavioral factors (such as anal sex) contribute to increased exposure to viral infections in this population.

The study’s intersectional lens is valuable, Gita Suneja, MD, said in an interview. “It is looking at racial and ethnic disparities within an already minoritized group, which is men who have sex with men living with HIV,” said the professor of radiation oncology at the University of Utah, Salt Lake City, Utah, who was not involved in the study.

“It’s really profound to me to sit back and think about how these disparities intersect, and how somebody can be so marginalized: it’s not just race or ethnicity, it’s not just having a stigmatized medical condition, it’s the confluence of all of these factors that leads to exclusion from care and poor outcomes.”

Standardized incidence ratios (SIRs), using men of the same ethnicity and age in the general population as the comparator, were reported for MSMWH of different racial/ethnic groups. For non-Hodgkin lymphoma, the SIR was 3.11 for White MSMWH, rising to 4.84 for Black MSMWH and 5.46 for Hispanic MSMWH. 

For Hodgkin lymphoma, the SIRs were 6.35, 7.69, and 11.5, respectively. For Kaposi sarcoma, they were many orders of magnitude higher, at 417 for White MSMWH, 772 for Black MSMWH, and 887 for Hispanic MSMWH.

In contrast, for anal cancer and liver cancer, the highest SIRs were among White MSMWH.

Given the role of immunosuppression, the researchers wanted to see whether cancer incidence differed according to prior AIDS diagnosis. However, they found that within each racial/ethnic group, there were no statistically significant differences in SIR according to AIDS status.

“There were disparities across the board for [racially minoritized] groups, regardless of immunosuppression status, which leads us to believe that it isn’t just about the diagnosis of AIDS, but about many other factors that we’re not capturing in the paper,” first author Benton Meldrum, MPH, told Medscape Medical News.

One study limitation is that AIDS diagnosis is an imprecise proxy for immunosuppression. It does not capture the duration and severity of immunosuppression, nor the extent of immune restoration. Many people with a previous AIDS diagnosis are now virally suppressed.

Database studies have inherent limitations in terms of the range of parameters recorded. In an ideal world, Meldrum said, they would have had access to information on CD4 count and viral suppression over time, as well as socioeconomic factors such as income and insurance status.

Differences in timely HIV diagnosis, viral suppression, and continued engagement in care are thought to drive the differences in cancer incidence. “HIV control today helps mitigate the risk of cancer development down the road,” Suneja said.

While not addressed by this study, there may be additional differences in cancer survival. Differences in cancer care, including prompt diagnosis and access to effective treatment, could play a role.

In terms of practical interventions to address these disparities, Suneja highlights the value of programs which help patients navigate a complex healthcare system. This may include care coordination navigation, peer navigation, and delivering services in community settings.

Such interventions don’t only benefit marginalized groups but help improve healthcare access and outcomes for everyone, she said. Even people with insurance and high health literacy often struggle to remain engaged.

“When we design healthcare systems to best serve those that have been left furthest behind, we all do better,” Suneja said.

The study was funded by the Intramural Research Program of the National Cancer Institute. Suneja and Meldrum reported having no relevant financial relationships. 

Roger Pebody is a freelance journalist based in Paris, France.