germinoma

A germinoma is a type of germ-cell tumor, which is not differentiated upon examination. It may be benign or malignant.

Germinomas are thought to originate from an error of development, when certain primordial germ cells fail to migrate properly. Germinomas lack histologic differentiation, whereas nongerminomatous germ-cell tumors display a variety of differentiation. Like other germ-cell tumors, germinomas can undergo malignant transformation.

The tumor is uniform in appearance, consisting of large, ...