Appendiceal submucosal mass as presentation of intestinal endometriosis

Submucosal lesions are mass-like protuberances into the gastrointestinal lumen covered by normal mucosa. Making a definitive diagnosis is difficult because of the number of benign and malignant lesions and extrinsic compression. Here we report the case of a 42-year-old woman referred for colon polypectomy. Colonoscopy revealed a polypoid formation with externalization from the appendicular orifice covered by normal mucosa and another formation at the sigmoid colon. The histopathology of both lesions was normal. Endoscopic ultrasound showed a hypoechoic lesion that was slightly heterogeneous in the fourth layer, and CT colonography confirmed the findings. Surgical therapy with ileocolic resection and resection of the sigmoid lesion was performed. Surgical specimens revealed an appendicular intussusception by endometriosis and endometrial foci in the sigmoid. Intestinal endometriosis may have several presentations, but it should always be considered in the differential diagnosis of a submucosal lesion in the colon.