Incidental risk of malignancy in mature cystic teratoma: experience of a single tertiary center

We aimed to evaluate the incidental risk of malignancy in mature cystic teratomas (MCT) and check the management. We retrospectively reviewed records of patients diagnosed and treated with MCT and divided patients into two groups as pure MCT and malignant transformation of MCT. In our clinic incidence of incidental malignant transformation of ovarian MCTs was 2.7%. Median age (p = 0.005) and mass size (p = 0.027) were statistically higher in malignant group. The most common histological type of malignant transformations was malignant struma ovarii (35.7%). In malignant group, five-year disease-free survival was 66.7% and five-year overall survival was 86.7%. Although the risk of malignancy in mature cystic teratomas is rare, it should not be ignored. Age, mass size, and preoperative imaging should all be evaluated with suspicion and if available, frozen section should be used. Management is inconsistent as a result of its rarity. New management practices should be developed with further studies.

Dermoid cyst; Mature cystic teratoma; Malignancy; Malignant transformation

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