Synchronous squamous carcinoma of the anus and adenocarcinoma of the rectum.

: Recent literature has reported several series of synchronous adenocarcinoma of the colon, but there has not been a reported case of synchronous squamous carcinoma of the anus and adenocarcinoma of the rectum. This article describes a patient with a large squamous carcinoma of the anus along with a large adenocarcinoma of the rectum, and also discusses a current review of the etiology and treatment of squamous carcinoma of the anus.