[Mucoid carcinoma of the anus and perianal fistula: a clinical case and review of the literature]. 
The Authors describe a case of mucoid anal carcinoma occurring in a perianal fistula.  Surgical treatment was an abdomino-perineal resection (Miles' operation).  On the basis of their experience and of the results reported in the literature, the Authors discuss the clinical and histological aspects of this association.