Markers of Immune Function and Survival Among Cancer Patients With HIV in the United States: A Population-based Registry Linkage Study

BACKGROUND: People with HIV (PWH) and cancer have greater cancer-specific mortality than patients without HIV, which may reflect effects of immunosuppression. We aimed to describe the associations between low CD4 cell counts and cancer-specific mortality in PWH with cancer. METHODS: We used linked data from HIV and cancer registries to study 12 common cancers in PWH in 14 registries in the United States and Puerto Rico in 2008-2019. We used Cox regression to estimate hazard ratios (HRs) for the association of CD4 counts measured after cancer diagnosis (0-49, 50-99, 100-199, and 200+ CD4 cells/mm3) with cancer-specific mortality, adjusted for demographic and cancer-related factors. We estimated 3-year cancer-specific cumulative mortality using Fine-Gray models. RESULTS: We evaluated 12,087 PWH and cancer (the most common being non-Hodgkin lymphoma [NHL, N=2311], prostate cancer [N=1681], and Kaposi sarcoma [KS, N=1423]). Cancer-specific mortality was significantly greater for individuals with a CD4 count of 0-49 compared to 200+ cells/mm3 for NHL (HR=1.82, 95%CI=1.30-2.53), prostate cancer (HR=3.98, 95%CI=1.56-10.15), KS (HR=4.16, 95%CI=1.49-11.67), lung cancer (HR=1.69, 95%CI=1.33-2.14), colorectal cancer (HR=2.79, 95%CI=1.58-4.92), and liver cancer (HR=1.44, 95%CI=1.01-2.70). For lung cancer, those with a CD4 count of 200+ cells/mm3 had 3-year cancer-specific cumulative mortality of 52% versus 72% for those with a CD4 count of 0-49. CONCLUSION: Among PWH with cancer, cancer-specific mortality increased with lower CD4 counts, including for solid tumors not associated with HIV, e.g., prostate and lung cancer. These results highlight the role of immunity in control of cancer.