Breast and Axillary Metastasis with Colon Cancer Primary Origin

Introduction: Colon cancer is the third most common cancer in gastrointestinal (GI) malignancies. Colorectal cancer most commonly metastasizes to the liver and lung. Metastasis to the breast from extramammary tumors are uncommon and metastatic colon carcinoma (MCC) to the breast is extremely rare. Case Presentation: We reported a 43-year-old woman with breast metastasis with colon origin. The patient presented with breast mass with mucinous adenocarcinoma. Conclusions: Metastasis to the breast from the colonic origin is possible. However, its occurrence is rare when mucinous adenocarcinoma of the breast mass is reported, and GI origin must be considered.