Isolated colonic metastasis from breast cancer 11 years after primary diagnosis

Colon is a very rare site of metastasis from breast cancer. Its diagnosis is challenging. We report a new case of 56-year-old woman who was previously treated for lobular breast carcinoma 11 years ago. Radiologic features on barium enema and computed tomography (CT) were concordant with primary cancer of the transverse colon. The true diagnosis was made by immunohistochemical study of hemicolectomy specimen, which showed positivity for CA 15-3, cytokeratin 7, estrogen receptor, and progesterone receptor and negativity for cytokeratin 20 and carcinoembryonic antigen (CEA). The patient received chemotherapy and hormonal therapy. After a follow-up of 17 months, she is still alive with no evidence of recurrence. Literature review revealed that diagnosis should be suspected in the presence of bowel disorders in women with history of breast cancer even several years later. Surgery is beneficial in only isolated colonic metastasis. Otherwise, the treatment is based on systemic therapy. The prognosis is usually poor.