Ovarian borderline mucinous tumor with carcinosarcomatous mural nodule: a case report of a rare entity and review of the literature

Background Ovarian mucinous tumors are histologically classified into benign, borderline, and malignant categories, with borderline tumors generally demonstrating an intermediate prognosis. However, ovarian borderline mucinous tumors with malignant mural nodules are associated with poor prognosis, where sarcomatous and anaplastic carcinoma mural nodules are common, whereas carcinosarcomatous mural nodules are rare. Case presentation This report describes a case of a 27-year-old female patient presenting with a two-year history of abdominal distension. Imaging studies revealed a large cystic-solid mass with abnormal signal characteristics. The patient underwent exploratory laparotomy combined with fertility-sparing staging surgery for suspected ovarian malignancy. Postoperative pathological diagnosis confirmed ovarian borderline mucinous tumor with carcinosarcomatous mural nodule. The patient subsequently received adjuvant chemotherapy, and at 5.5 months of follow-up, there has been no evidence of recurrence. Conclusion This case provides novel insights into the diagnosis of ovarian borderline mucinous tumor with a carcinosarcomatous mural nodule, contributing to an enhanced understanding and recognition of carcinosarcomatous mural nodules.