The authors described an uncommon case of 64-year-old male with mucinous adenocarcinoma arising in a long-standing anal fistula. After an appropriate staging, en bloc abdominoperineal resection with distal sacrectomy and myocutaneous flap reconstruction was performed. Post-operative period was uneventful. Pathological examination showed mucinous adenocarcinoma arising in anal fistula and invading the cortex, medulla of sacrum, and surrounding soft tissue. All surgical margins were free and there was no nodal metastasis. The patient had no evidence of recurrence after 2-year follow-up. The present paper reported a successful radical surgery for locally advanced primary adenocarcinoma of anal fistula, and reviewed the recent treatment options and their outcomes in patients with primary adenocarcinoma of anal fistula. A ‘new’ diagnostic criteria for primary adenocarcinoma associated with anal fistula are proposed in the discussion. Algorithm for the diagnosis and management of primary adenocarcinoma associated with anal fistula is shown at the end of this paper.

Keywords: Anal fistula, Malignancy, Surgery, Review, Algorithm

Received 8 Jun 2018 | Revised 27 Oct 2018 | Accepted 28 Oct 2018