This group of tumors includes germinomas, embryonal carcinomas, teratomas, endodermal sinus tumors, choriocarcinomas, and mixed tumors. Most germ cell tumors occur most frequently at the pineal gland with the exception of germinoma. Fatty tissue or calcification may be seen in teratomas. Histologically, germinomas range from more benign processes to highly malignant and can metastasize throughout the CSF spaces. The imaging appearance does not aid in determining aggressiveness. Lesions uniformly enhance.