Transformed teratomas represent a rare and aggressive form of germ cell tumor, characterized by the presence of a malignant somatic component within a typically mature teratoma.

This study aims to better understand the epidemiological, clinical, and histopathological characteristics of these atypical tumors.

Over a 13-year period, seven cases were included, as well as one case of carcinoid tumor, two cases of squamous cell carcinoma, and four cases of papillary thyroid carcinoma. Most of the patients were postmenopausal women presenting with large cysts.

The prognosis of transformed teratomas depends on early diagnosis, the nature of the transformed tissue, and the possibility of achieving complete surgical excision. Multidisciplinary management and rigorous follow-up are essential to improve survival in patients affected by this rare entity.