A systematic review and meta-analysis of mortality in anal cancer patients by HIV status

Abstract

Advances in HIV treatments have resulted in life expectancies among people with HIV (PWH) that are similar to people without HIV (non-PWH), provided that PWH have access to these treatments. As a result of increased survival times, diagnosis of non-AIDS-defining cancers, including anal cancer (AC), has increased among PWH. The purpose of this meta-analysis was to determine if PWH have a higher hazard of mortality compared to non-PWH following AC diagnosis in the post-highly active antiretroviral therapy (HAART) era. We searched PubMed, Embase, Web of Science, and conference abstracts from Jan 1, 1996 - October 31, 2018. Our analysis included longitudinal studies of adults diagnosed with AC which measured a hazard ratio (HR) of overall or cancer-specific mortality comparing PWH versus non-PWH. Using a random-effects model, we estimated the primary outcome, pooled overall survival HR, and the secondary outcome, cancer-specific survival HR. Study quality was assessed using the Newcastle-Ottawa Scale. Thirteen studies were relevant for inclusion, twelve of which had a low risk of bias. Meta-analysis of the studies reporting an overall survival HR found a non-significant pooled HR of 1.11 (95% CI: 0.85-1.44). Meta-analysis of the six studies reporting cancer-specific survival HR found a non-significant pooled HR of 1.15 (95% CI: 0.69-1.93). Heterogeneity was low and medium, respectively. Overall survival and cancer-specific survival HRs indicate that although PWH had higher mortality than non-PWH, the effects were not statistically significant. There is therefore no significant overall survival nor cancer-specific survival differences between PWH and non-PWH in the era of modern treatment.

Keywords: Anal cancer; HIV; Hazard ratio; Meta-analysis; Survival.