A 19-year-old woman undergoes laparotomy for a 15 cm adnexal cyst. The cyst contains hair, sebaceous material and teeth, arising from a Rokitansky protuberance. Microscopy shows mature tissues derived from all three germ layers. What is this tumour, and which variant carries malignant potential?
- A Serous cystadenoma; focal epithelial proliferation predicts malignancy
- B Immature teratoma; the neural tissue component determines grade
- C Mature cystic teratoma; struma ovarii is the variant with malignant potential ✓
- D Mucinous cystadenoma; pseudomyxoma peritonei signals malignant transformation
Correct answer: C. Mature cystic teratoma; struma ovarii is the variant with malignant potential
Explanation
Mature cystic teratoma (dermoid cyst) is the commonest ovarian tumour, typically in young women, containing mature elements of all three germ layers with hair, sebum and teeth from a Rokitansky protuberance. Struma ovarii, composed predominantly of mature thyroid tissue, is the recognised variant that can rarely be hyperfunctional or undergo malignant transformation. Immature teratoma is a separate malignant entity graded by immature neuroepithelium, and pseudomyxoma peritonei is linked to mucinous tumours, usually appendiceal, not dermoids.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.