Traumatic sigmoid colon rupture due to breast cancer metastasis: a case report.

The metastasis of breast cancer to the gastrointestinal tract is rare. Herein, we presented the case of an 85-year-old woman who had a history of invasive lobular carcinoma and experienced complete colon rupture due to relatively low-energy trauma. The patient underwent bilateral total mastectomy and axillary dissection following preoperative chemotherapy 6 years ago. She had a local recurrence 2 years after the surgery and underwent chemotherapy. Subsequently, the cancer metastasized to the thoracolumbar area and retroperitoneum. In addition, the patient fell from a height of 30 cm while hanging laundry and her abdomen hit a hose reel. Emergency surgery was performed, and the entire circumference of the sigmoid colon was ruptured. The ruptured colon lesion was resected, and the stump was closed. A double-barrel transverse colostomy was created as it was impossible to lift the stump up to the abdominal wall. Histopathological examination revealed the invasive lobular carcinoma metastasis and a linitis plastica-like change of the colon wall, which probably consequently weakened. In addition, minimal trauma can damage the gastrointestinal tract that had invasive lobular carcinoma metastasis.