Hsu W.-CCHI-HAU CHENRUEY-JIEN CHENSONG-NAN CHOW2020-02-192020-02-1920041028-4559https://scholars.lib.ntu.edu.tw/handle/123456789/460812Objective: We report two cases of lower abdominal tumor with acute bowel obstruction. Preoperatively, gynecologic tumors were considered to be the cause. However, colorectal cancer was discovered during exploratory laparotomy. Case Reports: An 81-year-old obese woman suffered from lower abdominal pain for some days, and there had been no stool passage for 2 weeks. Plain abdominal film revealed a dilated bowel lumen. A right ovarian cystic tumor was noted from pelvic sonography. The bowel obstruction was considered to be a result of external compression of the ovarian tumor. However, adenocarcinoma of the colon with lymph nodes and right ovary metastasis was confirmed by exploratory laparotomy. In the second case, a 45-year-old obese woman had problems with changed bowel habit (diarrhea and frequency) in the last 6 months. A huge uterus above the umbilicus with multiple myomas were revealed by pelvic sonography. Plain abdominal film showed a distended bowel lumen. Multiple huge exophytic myomatous masses in the uterus and metastatic adenocarcinoma to the left ovary were confirmed at laparotomy. Conclusion: Although a lower abdominal tumor with bowel obstruction can be considered to be a result of a gynecologic tumor by physical examination and sonography, colorectal cancer should be included in the differential diagnosis. ? 2004 Taiwan Association of Obstetric & Gynecology.[SDGs]SDG3journal article10.1016/S1028-4559(09)60056-52-s2.0-67651121793