Sister Mary Joseph's nodule is sometimes the first sign of an internal malignancy, including gastrointestinal, gynecological, or malignancy of unknown primary. It is rarely the sole presentation of a primary peritoneal cancer. In this report, we present the case of a 70-year-old female with umbilical drainage and a computed tomography scan consistent with solitary umbilical nodule. Excision of the nodule revealed adenocarcinoma of likely müllerian origin. Surgical staging did not show any evidence of malignancy with the exception of pelvic washings. She was considered to have primary peritoneal adenocarcinoma and was treated with adjuvant chemotherapy.
Keywords: Müllerian origin; Umbilical metastasis.