[Anorectal tumor pathology and its diagnosis]

Anal cancer is very rare, but its diagnosis is often too late. Treatment is usually non surgical and can be very effective. Prognosis can be improved by earlier diagnosis. Proctoscopy is mandatory for all symptomatic patients. Could an high risk population be determined, the incidence of anal cancer could fall. By contrast, rectal cancer is one of the most frequent and its prognosis has not been improved. Hope can be found in screening and prevention; these will be more effective when the transformation sequence of adenoma to cancer will be entirely explained.