Consent statement:Written informed consent was obtained from the patient’s parents to publish this report in accordance with the journal’s patient consent policy
Abstract: Primary mediastinum immature teratoma with somatic-type malignant transformation (SM) is extremely rare, and the clinical prognosis is poor. Immature teratoma with SM is hardly to be eradicated by chemotherapy for the poor sensitivity, therefore surgical resection is recommended whenever possible for it may offer a better survival. We herein report a case of a chemotherapy-resistant and extremely giant immature teratoma who received en bloc resection with pathologic findings of foci of sarcoma and poorly differentiated squamous cell carcinoma, and the literature is reviewed. To our best knowledge, this is the largest primary mediastinum immature teratoma with somatic-type malignant transformation treated with an en bloc resection so far.
Key words: Primary mediastinum immature teratoma, somatic-type malignant transformation, en bloc, surgery