Epidemiological trends of HPV-related anal cancers amongst males globally: A systematic literature review.

Abstract

492 Background: Anal cancer is associated with human papillomavirus (HPV), a sexually transmitted infection, which can be prevented by the HPV vaccination. Few countries do recommend vaccination for the male population, but all males are at risk of contracting HPV. This study aimed to identify the latest evidence on the incidence of anal cancer and pre-cancer related to HPV in males globally and to analyze the epidemiological trends. Methods: A systematic literature search was performed using Medline and EMBASE. Studies containing original anal cancer incidence data in males published between January 1, 2008 and March 23, 2018 in English were included. Results: The global incidence of anal cancers and pre-cancers among the general male population was identified in 25 studies with observations ranging between 1968 and 2014. Incidence over time was reported in Australia and Europe. In an Australian national study, anal cancer incidence increased from 0.77 to 1.3 per 100,000 persons from 1982-2005, and in the UK from 0.79 to 1.06 per 100,000 persons from 1962-2002. In Denmark, the anal cancer range increased from 0.20-0.41 to 0.69-1.3 per 100,000 person-years (PYs) from pre-2000 to post-2000, and in France from 0.2 to 0.5 per 100,000 PYs from 1982-2012. In two national US studies, the mean incidence of pre-cancers was 1.5 in the period 1997-2009, and 0.41 from 1978-2007 per 100,000 PYs. The burden of anal cancers and pre-cancers increased the most among high-risk males reported in US studies. For HIV-positive males, mean incidence of cancer increased from 10.5 during 1980-1989 to 42.3 in 1996-2004 per 100,000 PYs, and for HIV-positive MSM, incidence increased from 47 to 270 per 100,000 PYs between 1984 and 2013. The mean pre-cancer incidence among HIV-positive males increased from 1.7 during 1980-1989 to 29.5 in 1996-2004 per 100,000 PYs. Conclusions: This systematic literature review demonstrates the increase in anal cancer and pre-cancer incidences over time in men, especially in high-risk male populations. The burden of anal cancers and pre-cancers increase over time in all male populations highlights the unmet medical need and the importance of preventative interventions such as HPV gender-neutral vaccinations.