Abstract
Primary retroperitoneal serous adenocarcinoma (PRSA) is a rare malignancy of which only seven cases have been reported in the literature. The clinical features and outcomes of PRSA are not well understood. We herein report a case of PRSA with liver metastasis in a 74-year-old woman who was treated with surgical excision. The tumor cells were positive for estrogen receptor, Wilms tumor 1, PAX8, p53, and cytokeratin AE1/AE3. The final diagnosis was PRSA and liver metastasis. The pathological features of PRSA resemble those of ovarian serous carcinoma, which suggests that a combination of surgical excision with adjuvant chemotherapy may be the best option.