When size deceives: a giant 23 kg ovarian tumor mimicking malignancy in a young woman

Abstract

Mucinous borderline ovarian tumors are epithelial ovarian neoplasms characterized by epithelial proliferation and nuclear atypia in the absence of stromal invasion and commonly occur in women of reproductive age. We reported the case of a 25-year-old woman with progressive abdominal distension over two years. She had a height of 157 cm, weight of 115 kg, and a body mass index of 46.7 kg/m². Clinical examination revealed a massive abdominopelvic mass measuring approximately 40×40 cm occupying the entire abdomen. Magnetic resonance imaging demonstrated a 40×28×28 cm multiloculated cystic lesion extending to the epigastrium, containing enhancing solid components, papillary projections, and a large enhancing solid plaque measuring 15×6 cm. Loculated ascites with focal peritoneal thickening was also noted. Serum CA 19-9 was markedly elevated at 1950 U/ml, while other tumor markers remained within normal limits. Staging laparotomy revealed a giant 45×45 cm solid-cystic ovarian mass weighing 23 kg along with approximately 100 ml of straw-colored ascitic fluid, without evidence of gross peritoneal deposits. Histopathological examination confirmed the diagnosis of a mucinous borderline ovarian tumor. This case highlights the rare occurrence of giant mucinous borderline ovarian tumors in contemporary clinical practice and demonstrates the association of markedly elevated CA 19-9 levels with mucinous ovarian neoplasms. Complete surgical excision remains the cornerstone of management and is associated with an excellent prognosis when the disease is confined to the ovary.