Three cases of Cerebral Germinomas, one of them situated in the pineal region (topical) and two ectopical of the so called suprasellar or chiasmal Germinomas are studied. These last ones may be more aggressive than the congeneral topical ones, since besides it's dissemination throughout the basal cisternas they usually infilstrate into de walls of the III Ventricle, Fornix, Hypothalamus, Chiasma and Optic nervs. A high level of proteins in the spinal fluid without proportional increase of the cells is characteristic. Globulins are the predominant fraction of the increased spinal fluid proteins, as indicated by the highly positive laboratory test. These globulins are possibly produced by the lymphocytes which are part of this neoplasm. The high level of protein in the spinal fluid without proportional increase of the cells, in the presence of intracranial syndrome in a child or adolescent, with anatomical signs of basal localization make the possibility of a Chiasmal Germinona highly probable.