Anorectal squamous carcinoma in two homosexual men.
D000328:Adult; D001005:Anus Neoplasms / Q000453:epidemiology* / Q000276:immunology; D002294:Carcinoma, Squamous Cell / Q000453:epidemiology* / Q000276:immunology; D006716:Homosexuality; D006801:Humans; D008297:Male; D008875:Middle Aged; D012004:Rectal Neoplasms / Q000453:epidemiology* / Q000276:immunology; D012306:Risk