Endometriosis of the Sigmoid Colon Presenting as Colitis or Malignancy with Bowel Obstruction: Two Surgical Case Reports.

Background Endometriosis is a chronic gynecological condition characterized by the presence of endometrial-like tissue outside the uterus, often causing pain, infertility, and gastrointestinal symptoms like constipation. While intestinal involvement is less common, it can, in rare cases, lead to bowel obstruction. The prevalence of intestinal endometriosis ranges from 3% to 37% of all cases, with bowel obstruction due to endometriosis being particularly rare, occurring in 0.1% to 0.7% of cases. The most common sites of intestinal involvement include the ileum 38.3%, rectosigmoid 34.5%, ileocecal junction and appendix 14.9%, and rectum 10.2%. (1) We present two cases whose endometriosis involved the sigmoid colon, mimicking as a colitis or malignancy with primary bowel obstruction, required surgival interventions and histopathology confirmation to the origin of tissue.