Primary sigmoid adenocarcinoma metastasis to the breast in a 28-year-old female: a case study and a review of literature.

Metastasis to the breast from colorectal carcinoma is rare, only a few cases have been reported in the literature, and no cases have been reported in a young, 28-year-old patient. This report confirms the occurrence of the disease in a younger age group. The patient was referred to the Breast Clinic with a history of a gradually increasing lump in her right breast for two weeks' duration. On clinical examination, a 2-cm firm lump was noted in the upper inner quadrant of the right breast, which was clinically benign; however, histological examination of the breast core biopsy together with immunohistochemistry confirmed metastatic colorectal adenocarcinoma. The primary colorectal carcinoma was later confirmed to be a stage pT4N2M1 tumor, and the Duke stage was C1. Histology with immunohistochemistry is very important in the diagnosis of cases of this nature, but the clinical correlation should be taken into consideration at multidisciplinary team meetings to decide the final management of the patient.