Malignant Transformation in Mature Cystic Teratomas of the Ovary: Case Reports and Review of the Literature.

Malignant transformation occurs in 1.5-2% of mature cystic teratomas (MCT)s of the ovary and usually consists of squamous cell carcinoma, whereas other malignancies are less common. Diagnosis and treatment represent a challenge for gynecologic oncologists. The preoperative detection is very difficult and the diagnostic accuracy of imaging examinations is uncertain. The tumor is usually detected post-operatively based on histopathologic findings. This paper reviewed 206 consecutive patients who underwent surgery for a histologically-proven MCT of the ovary between 2010 and 2017. Malignant transformation occurred in 3 (1.5%) of them, and consisted of squamous cell carcinoma in one, type 2 papillary renal carcinoma in one, and papillary thyroid carcinoma in another one. The paper reported the clinical, radiological and histological features of these cases and reviewed the literature data on the treatment options.