Has the Expected Shift in HIV-Related Cancers Occurred? Findings from a Long-Term HIV Cohort in Turkey

Background/Objectives: Despite widespread antiretroviral therapy (ART) use, whether the expected transition from AIDS-defining to non-AIDS-defining cancers has occurred in settings with persistent late HIV presentation remains unclear. We examined long-term cancer patterns, determinants, and survival outcomes in a large HIV cohort. Methods: This retrospective, single-center cohort included 1419 people living with HIV followed between 2006 and 2024. Patients who developed malignancy were classified as AIDS-defining cancers (ADC) or non-AIDS-defining cancers (NADC). Immuno-virological parameters were assessed at HIV and cancer diagnosis. Survival was analyzed using Kaplan-Meier methods, and predictors of mortality were evaluated using Cox proportional hazards regression. Determinants of ADC development were assessed using multivariable logistic regression. Temporal changes were evaluated by trend analysis. Results: Sixty-six patients (4.6%) developed malignancy (31 ADC, 35 NADC). Late HIV presentation was common, with 72.7% having CD4+ T-lymphocyte counts < 350 cells/mm³ at cancer diagnosis, particularly among ADC cases. Most ADCs (93.5%) occurred within 24 months of HIV diagnosis. Overall survival did not differ between ADC and NADC groups (log-rank p = 0.14). Although mortality declined after 2015, temporal changes in ADC and NADC proportions did not reach statistical significance (p = 0.14). In Cox regression analysis, viral suppression before death or last follow-up was independently associated with lower mortality risk (HR 0.12; 95% CI 0.05-0.31). Lower CD4+ T-lymphocyte counts were associated with ADC development, and a CD4+ T-lymphocyte threshold of 295 cells/mm³ showed good discriminative performance (AUC = 0.83), although this cutoff should be interpreted cautiously due to the lack of external validation. Conclusions: In this long-term cohort from Türkiye, a clear epidemiological transition from ADC to NADC could not be demonstrated. The cancer spectrum remained strongly influenced by late HIV presentation and advanced immunodeficiency. Sustained viral suppression was independently associated with lower mortality risk, supporting the importance of early HIV diagnosis, timely ART initiation, and sustained virological control.