Carcinoma in Anorectal Fistulas of Crohn’s Disease with Seton Drainage

In December 2004, an anorectal fistula at the 11 o’clock position was treated with seton drainage. In January 2005, another fistula at the 5 o’clock position was also treated with seton drainage. The anus was stenotic, ! 1.5 cm in diameter due to chronic anorectal inflammation and scarring. In October 2005, a granulation around the fistula enlarged with elastic hard contents. Biopsy revealed adenocarcinoma. CT and magnetic resonance imaging (MRI) showed a massive tumor around the anorectal fistula invading the muscle and the perineal space. Abdominoperineal resection was performed with a combined resection of the posterior wall of the vagina due to the tumor invasion. Pathological findings showed a moderately differentiated adenocarcinoma in and around the fistula invading the surrounding tissue. Postoperatively, she received chemotherapy with UFT (tegafur and uracil). Her CD condition has remained stable without any signs of cancer recurrence so far 24 months since the radical operation.