Radiological‐pathological correlation of malignant teratoma with liposarcomatous transformation: Proven by repeated transthoracic needle biopsy

A mediastinal germ cell tumor with a sarcomatous component is extremely rare and is accompanied by a poor prognosis. Clinical and radiologic diagnosis is very difficult. Herein, we report a rare case of anterior mediastinal malignant teratoma containing a growing liposarcomatous component and detail the diagnostic process. The case was diagnosed by repeated transthoracic needle biopsy and correlated with changes in follow‐up chest computed tomography and serum tumor markers. We also provide a review of the literature.