Synchronous anal mucinous adenocarcinoma and anal tuberculosis presenting as chronic anal fistula: Challenging management

Abstract

Metachronous anal tuberculosis to an anal adenocarcinoma is an exceptional condition. The aim of our study was to report management of the first case of synchronized anal canal adenocarcinoma and anal canal tuberculosis and report our multidisciplinary approach. A 71-year-old man was admitted for non-healing anal fistula. Rectal examination at supine position showed an ulcerative growth at the medio-superior quadrant on a radius of 2cm from the anal verge. Digital rectal examination assessed no tumor in the anorectum. Biopsy of fistulae confirmed diagnosis of anal mucinous adenocarcinoma with coexisting anal tuberculosis. Further exploration confirmed diagnosis with no distal metastasis, no active pulmonary tuberculosis and no immunodepression. Adjuvant anti-bacillary chemotherapy was initiated 1 month prior to adjuvant radio-chemotherapy. Patient was re-admitted at the 6th week following the last dose of radio-chemotherapy for surgery. On long-term evaluation at 10 months, the patient reported absence of symptoms with weight gain. Association of both entities is rare. Chronic inflammatory damage may possibly initiate a sequence of metaplasia and dysplasia, resulting in neoplastic transformation. Anal canal adenocarcinoma treatment follows same guidelines as rectal cancer. Extra-pulmonary tuberculosis treatment follows anti-bacillary protocol with consequent side effects. Therefore, our case is a unique clinical challenge for physicians. Management decision was multidisciplinary process. Their pathophysiology relationship is yet to be understood. Moreover, each entity has defined and individual therapeutic protocols and indications. All this taken into consideration, such case presents a clinical and therapeutic challenge for physicians.