Biology and Microscopic Morphology of Posterior Fossa Tumors

Brain tumors are among the most frequent neoplastic diseases of childhood, being sur-passed in frequency only by leukemia and, in early infancy, by renal neoplasms. Whereas in early infancy supratentorial tumors predominate, starting with the fourth or fifth year the number of infratentorial tumors exceeds that of cerebral neoplasms, the rates being 60% to 40%, respectively, in the statistics of Koos and Miller1 or 55% to 45% according to Brett.2 After adolescence, the figures fall rapidly down to about 20%, and supratentorial tumors are again predominant. A satisfying explanation of this and of many other biological aspects of childhood central nervous system (CNS) tumors is at present not available. These points have been recently discussed in extenso by Giuffre.3