Three Cases of Anal Cystic Lesions in Our Hospital

Abstract

Anal cystic lesions are extremely rare. From October 2011 to August 2023, 3 (0.12%) of the 2498 anal surgery cases performed in our hospital had cystic lesions. They were 38, 56, and 69 years old, all male, and cystic lesions were located anterior to the anus. The cysts were elastic and soft, and the preoperative diagnosis was thrombosed external hemorrhoids or cysts, but histopathologic examination revealed epidermal cysts in two cases and teratoma in one case. Teratomas in the anus show similar histological features to tailgut cysts and retrorectal cyst-hamartomas, and are thought to be rare cysts caused by the remnants of cloaca. They are usually located in the retrorectal space; cases located in the perianal region are extremely rare, and only four cases including ours have been reported in Japan. We present each case and report a case of teratoma in the anal region with a review of the literature.