A Case Report of a Giant Mucinous Cystadenoma Suspected to Be Associated with Ovarian Remnant Syndrome After Bilateral Adnexectomy: Diagnostic Pitfalls and Implications for Clinical Management

Background

Mucinous cystadenoma of the ovary is one of the common benign ovarian neoplasms. Nevertheless, when a huge pelvic mass develops years after bilateral adnexectomy, determining its tissue origin and establishing a differential diagnosis poses substantial challenges, complicating the clinical management of such secondary pelvic lesions. Case Presentation: This study reports a rare case of a giant pelvic mass occurring many years after bilateral adnexectomy in a 65-year-old Han Chinese female. Intraoperative exploration and postoperative histopathology confirmed the lesion as an ovarian mucinous cystadenoma, which was presumed to arise from residual ovarian tissue after previous surgery, consistent with ovarian remnant syndrome (ORS). However, the ovarian origin of this lesion was comprehensively determined based on prior surgical records, intraoperative findings, and histopathological morphology, without further confirmation by definitive immunohistochemical staining.