26. Retrospective analysis of HIV-infected men with anal cancer attending the Toronto General Hospital Immunodeficiency Clinic, Toronto, Ontario, Canada (1985–2013)

Abstract

Background: The incidence of anal cancer (AC) in Canada is 1.5/100 000 but HIV-infected individuals have incidence rates from 49–144/100 000. It is important to examine risk factors for this difference. Methods: A retrospective chart review was performed to look at risk factors in patients with the diagnosis of ‘anal cancer’ attending the Toronto General Hospital Immunodeficiency Clinic (TGH-IC) in Toronto, Ontario, Canada, from 1985 to 2013. There were 5200 clinic attendees. Results: 36 (0.96%) males attending TGH-IC were diagnosed with AC between 1985 and 2013; 17 (47%) were diagnosed since 2008. 7 (19.4%) are deceased; 6 (16.7%) as a result of AC. Mean age at diagnosis was 56 ± 9.8 years compared with mean age at TGH-IC of 48 ± 15.9 years (P = 0.015). 33 (91.7%) were on anti-retroviral therapy (ART) at time of diagnosis. Compared with current ART use, 30 (90.9%) vs 727 (72.6%; P = 0.015) were on nucleoside reverse transcriptase inhibitors (NRTIs); 22 (66.7%) vs 554 (55.3%; P = 0.015) were on protease inhibitors; 8 (24.2%) vs 471 (47.0%; P = 0.015) were on NNRTIs. Median CD4 count at diagnosis was 265 cells mm^–3, compared with the TGH-IC of 425 cells mm^–3 (P = 0.04). A tobacco history (former or current) was found in 24 (72.7%) with AC vs 2232 (41%) without AC (P = 0.015). 35 (97.2%) underwent treatment: combination chemotherapy and radiation therapy being the most common in 23 (63.9%). Conclusions: In 28 years, there have been a total of 36 males diagnosed with anal cancer at TGH-IC. They were older, had a lower CD4 count and were more likely to be smokers. Combination chemotherapy and radiation therapy remains the mainstay of treatment for AC.