Background: Immunesuppression for HIV-infection or anti-rejection therapies aftter organ transplantation is a well known risk factor for cancer. This increased risk has been well documented for young adults, whereas few data are available on older persons. In this study, we assessed the impact of cancer in HIV-positive persons (HIV+) and in transplant persons (TRP) aged 50 years or older.

Methods: Data from a multi-cohort study conducted in Italy and France were analysed. Individuals >=50 years of age were selected from the original study group constituted by 2002 HIV+ seroconverters from Italy, 6072 HIV+ from France and 2755 Italian TRP (1844 kidney, 702 heart, 159 liver and 50 lung TRP). Sex- and age-standardized incidence ratios (SIR) and 95% confidence intervals (CI) were computed to quantify the cancer risk as compared to the general population. Among HIV+, the risk of cancer was also assessed according to treatment with highly active antiretroviral therapies (HAART).

Results: This analysis was based on 94 cancers diagnosed in 833 HIV+, and on 154 cancers  diagnosed in 1558 TRP >=50 years of age. The SIRs for all cancers decreased with ageing, ranging from 5.1 (95% CI:4.0-6.5) in HIV+ aged 50-59 to 2.1 (95% CI:1.4-3.1) in HIV+ aged 60 or older. In TRP, the SIRs for all cancer were 2.5 (95% CI:2.0-3.1) and 1.6 (95% CI: 1.2-2.0), respectively. In HIV+, the protective effect of HAART was more evident in those aged 50-59 (SIR=6.8 in never treated and SIR=2.4 in ever treated) than in HIV+ aged >=60 (SIR=2.8 and SIR=1.6, respectively). This pattern of cancer occurrence was peculiar to virus-related cancers (e.g., Kaposi’s sarcoma, non-Hodgkin’s lymphoma, liver cancer). SIRs for lung cancer in both groups were significantly increased but did not significantly differ according to HAART and/or age. The survival of both HIV+ and TRP was significantly reduced by the diagnosis of cancer, but the difference in survival was not associated with ageing (p=0.20).

Conclusions: The findings of this analysis suggest that in aged individuals with acquired immunesuppression the spectrum of cancer pattern is similar to the one observed in younger persons with immunosuppression. However, the burden of cancer will increase in absolute terms in these population groups, because of the increasing proportion of older individuals among both HIV+ and TRP calling for primary and secondary preventive interventions.