The progression in astrocytic tumors.

Progression represents the qualitative tumor evolution during the time. Recently it received great consideration, mainly since the introduction of the neuroradiological imaging (CT and MRI). A series of 224 supratentorial astrocytic tumors of the juvenile and adult age have been analyzed: we found the morphological features of progression in 26% of them. These data introduce, perhaps, the most important information about progression: the "crisis" of the concept that low-grade tumors are stable lesions during the time.