A fatal case of carcinoma arising from a pilonidal sinus tract

We report a male patient with carcinoma arising on the basis of neglected s acrococcygeal pilonidal sinus disease. Following initial operation, perform ed without suspicion of malignancy, histology demonstrated cellular atypia and an increased mitotic rate. A second, wider tissue excision was recommen ded but the patient declined further surgery. Two years later, he presented with fungating carcinoma involving the rectum but again declined surgery. This rare case demonstrates that the presence of carcinoma should be suspec ted in long-standing, although innocent-looking, pilonidal sinus disease. I n the circumstance of uncertain histologic diagnosis, more generous surgica l sampling is required. Every effort must be made to overcome patient's rel uctance to accept a second, possibly life-saving procedure.