A 34-year-old woman presents with progressive abdominal distension over two years. At laparotomy she has a huge multiloculated cystic ovarian mass filling the abdomen, weighing 14 kg, with smooth glistening walls filled with sticky gelatinous mucin. Frozen section shows no atypia and no stromal invasion. What is the most likely diagnosis?

• A Serous cystadenoma
• B Mature cystic teratoma
• C Mucinous cystadenoma ✓
• D Borderline serous tumour

Explanation

Mucinous cystadenomas are classically the largest of all benign ovarian tumours and can reach enormous sizes filling the whole abdomen. They are unilateral, multilocular, filled with thick mucin, and lined by a single layer of tall columnar mucin-secreting epithelium resembling endocervical or intestinal cells. Serous cystadenomas are more commonly bilateral and smaller, dermoids contain ectodermal elements such as hair and fat, and borderline serous tumours show epithelial proliferation with atypia absent here.

Reference: DC Dutta's Textbook of Gynecology, 9th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.