An appraisal of the World Health Organization classification of tumors of the central nervous system.

An important development in the classification of tumors of the central nervous system was the nomenclature recommended by the World Health Organization in 1979. Since then, wide usage has suggested that the classification be modified to account for problems that neuropathologists have encountered. Although no classification is ideal, modification of certain tumor categories, particularly from the perspective of childhood brain tumors, is desirable. These are discussed in detail. Greater emphasis on standardization of the localization of brain tumors is also recommended. This appraisal suggests changes that will allow a consensus on nomenclature of central nervous system tumors so that a workable classification is the end product.