Abstract: | A 51-year-old woman visited our clinic her chief complaint being right hypogastric discomfort. An abdominal ultrasonography revealed a circular, cystic mass in the right hypogastric region. A colorectal radiography disclosed a semi-globular shadow defect at the end of the cecum and did not visualize the appendix. A colorectal endoscopy revealed a submucosal tumor accompanied by a central dimple which seemed to represent the ostium appendicis vermiformis. Based on a preoperative diagnosis of submucosal tumor, the patient underwent a partial resection of the cecum. A histopathological examination of tissue removed led to a diagnosis of endometriosis of the appendix. In Japan, 7 cases of endometriosis of the appendix have been reported to date. In those cases, endometriosis of the appendix was detected as a lesion accompanying endometriosis of some other site or during laparotomy was based on a diagnosis of acute appendicitis. Unlike these cases, the patient presented here had been diagnosed by a preoperative colorectal radiography and endoscopy as having a submucosal tumor of the appendix. |