Breast Cancer Metastasis to Colon

Breast cancer metastasis to the colon is exceedingly rare, with only 17 reported cases in the literature thus far. This report describes a 67-year-old female who presented to the Emergency Department for large volume melena in the setting of bilateral metastatic ductal breast carcinoma, left triple negative and right HER2+, and T4N0M0 non-small cell lung cancer. On routine CT abdomen/pelvis imaging, the patient had a 7 cm mass arising from the transverse colon. Colonoscopy revealed a non-obstructing necrotic mass in the proximal descending colon. The patient underwent a partial colectomy, small bowel resection, and gastric wedge resection. The patient recovered from surgery and was discharged home with palliative services. The patient passed away four months after discharge due to numerous metastases.