Her‐2/neu evaluation in Sister Mary Joseph’s nodule from breast carcinoma: a case report and review of the literature

Sister Mary Joseph’s nodule (SMJN) involving the umbilicus can often be a clinical sign of metastatic cancer, but rarely cancer originating from the breast. We report a rare case of umbilical metastases from breast cancer and reviewed the literature. A 54‐year‐old woman was referred to a pre‐surgery clinic for an examination of an umbilical nodule. The patient had a history of ductal breast carcinoma. Cytological smear from fine needle aspiration showed epithelial neoplastic cells resembling those of breast carcinoma. Neoplastic cells from tissue were positive for cytokeratin 8–18, estrogen and progesterone receptor and negative for E‐cadherin and had a low proliferative index. Her‐2/neu immunodetection showed a 2+ equivocal positive rate, but Her‐2/neu gene amplification was found on the cytological smear by fluorescence in situ hybridization analysis. Similar results were obtained within a tissue section. Concordant findings have been obtained when comparing the recent American Society of Clinical Oncology/College of American Pathologists scoring system. Fine needle aspiration from the SMJN is a useful tool for the diagnosis of metastatic breast cancer. Furthermore, the predictive biomarkers for tumors of the breast, hormonal receptors and Her‐2/neu not only assist with the identification of the source of the metastatic disease but also provide clinical information for patient management.