2025 Volume 50 Issue 3 Pages 299-305
A 79-year-old woman with a diagnosis of gastrointestinal perforation, presenting with abdominal pain and intra-abdominal free air on computed tomography scan. Prior to the perforation, she had received chemotherapy for advanced breast cancer for 3 months, and the chemotherapy had shown efficacy: a tumor in the right axilla involved lymph nodes reduced in size from 54 mm to 21 mm, and the serum level of the tumor marker, CEA, decreased from 17.4 ng/ml to 10.5 ng/ml. Emergency laparotomy revealed an 8-mm perforation of the jejunum, 20 cm from the Treitz ligament. We performed a partial small bowel resection. Histopathological examination showed tumor cell invasion of the submucosal to subserosal layers. The tumor cells exhibited edematous changes, suggesting cellular degeneration and the antitumor effects of chemotherapy. Intestinal perforation due to breast cancer metastasis is extremely rare, and the mechanism of such perforation remains unclear. In this case, evidence of the efficacy of chemotherapy was obtained from the imaging findings, serum tumor marker levels, and histopathological findings. Based on the findings, we considered that the intestinal perforation was caused by the response to chemotherapy in this case.
