HIV Infection, Cancer Treatment Regimens, and Cancer Outcomes Among Elderly Adults in the United States

Importance: HIV-infected patients with cancer have an elevated cancer-specific mortality rate compared with HIV-uninfected patients with cancer. However, to our knowledge, studies describing this association have not adjusted in detail for cancer treatment, despite evidence of suboptimal cancer treatment in the setting of HIV. Objective: To compare cancer-specific mortality in HIV-infected and HIV-uninfected patients with cancer after adjusting for available data on receipt of specific cancer treatments. Design, Setting, and Participants: We used Surveillance, Epidemiology, and End Results-Medicare linked data to identify 308 268 patients in the United States (age, ≥65 years), including 288 with HIV infection, with nonadvanced cancers of the colorectum, lung, prostate, or breast diagnosed between 1996 and 2012 who received standard, stage-appropriate cancer treatment during the year after cancer diagnosis. Data analysis was done from August 2016 to September 2018. Exposures: HIV infection identified by the presence of Medicare claims. Main outcomes: Overall mortality, cancer-specific mortality, and relapse or cancer-specific mortality after initial treatment. Results: In this database study of 308 268 patients with nonadvanced cancer (168 998 men and 139 270 women; age, ≥65 years), HIV-infected patients (n = 288) had significant elevations in the overall mortality rate compared with HIV-uninfected patients for cancers of the colorectum (hazard ratio [HR], 1.73; 95% CI, 1.11-2.68; P = .02), prostate (HR, 1.58; 95% CI, 1.23-2.03; P < .01), and breast (HR, 1.50; 95% CI, 1.01-2.24; P = .05). Cancer-specific mortality was elevated for prostate (HR, 1.65; 95% CI, 0.98-2.79; P = .06) and breast cancer (HR, 1.85; 95% CI, 0.96-3.55; P = .07). Compared with their HIV-uninfected counterparts, HIV-infected men with prostate cancer also experienced significantly higher rates of relapse or death (HR, 1.32; 95% CI, 1.03-1.71; P = .03) as did HIV-infected women with breast cancer (HR, 1.63; 95% CI, 1.09-2.43; P = .02). Conclusions and Relevance: In the United States, elderly HIV-infected patients with cancer, particularly prostate and breast cancers, have worse outcomes than HIV-uninfected patients with cancer. This disparity persists even after adjustment for administered first-course cancer treatments and will become increasingly relevant as the HIV population in the United States continues to age.