17-year-old female presented to her primary physician's office for a regular physical and was found to have a large intra-abdominal mass on physical exam, confirmed with ultrasound and CT scan, which revealed a large multiloculated cystic right ovarian mass. Her preoperative beta hCG, AFP and LDH were normal. Her CA 125 was elevated.

Surgical biopsy: confirmed ovarian mucinous cystadenoma and with adjacent mature cystic teratoma.

Pathology: Right adnexa: A large, tan-pink, lobulated mass weighing 322 g and measuring 18.3 x
12.2 x 5.7 cm was sent to pathology. Sectioning revealed a multiloculated cystic structure which exuded a tan/yellow, mucoid, viscous fluid when cut. Solid areas were interspersed among multiloculated cysts. A single nodular excrescence measuring 0.7 cm was located in one of the cyst walls. Sectioning of this nodule revealed a cystic cavity filled with amorphous, granular debris mixed with hair.

Discussion

Mucinous cystadenomas are benign ovarian epithelial neoplasms. They vary widely in size, are usually multilocular, and primarily cystic. They can be associated with other ovarian tumors such as teratomas, granulosa cell, carcinoid, and Brenner tumors. They represent 20-25% of all benign ovarian neoplasms and 75-85% of all ovarian mucinous tumors.