ADENOCARCINOMA IN THE ANAL-CANAL ASSOCIATED WITH A FISTULA - REPORT OF A CASE

Adenocarcinoma in the anal canal associated with an anal fistula is ex tremely rare, and in most eases its origin is difficult to ascertain b ecause the primary sites have already been destroyed before any diagno sis of malignancy is able to be made, We report herein the case of a 6 2-year-old man found to have papillary adenocarcinoma with partial muc inous carcinoma associated with an anal fistula. The tumor was not exp osed to the mucosal surface of the anal canal or rectum and an abdomin operineal resection was carried out. Macroscopic findings suggested th at the tumor had developed from the anal fistula; however, the tumor s howed a positive result when tested for O-acetylated sialic acids. Thi s test also proved positive in the mucus of normal rectal mucosa, but not in the mucus of the anal glands, We speculated that the results of these tests mag indicate that this tumor could have originated from t he rectal mucosa, from where it migrated into the anal fistula.