Rare Case of Sarcomatoid Squamous Cell Carcinoma Arising in an Ovarian Mature Teratoma.

Although mature cystic teratoma (MCT) is benign, malignant transformation (MT) occurs in ∼ 1% to 2% of all cases, and usually consists of squamous cell carcinoma (SCC), which accounts for ∼ 80% of the cases. Spindle-cell (sarcomatoid) carcinoma (SCSC) is an uncommon type of SCC, comprising up to 3% of all cases. The lack of characteristic symptoms and specific imaging findings may lead to preoperative misdiagnosis.