Table of Contents
Washington University Experience | NEOPLASMS (EMBRYONAL) | Medulloblastoma, Histologically Defined | Extensive Nodularity (MBEN) | 4A3 Medulloblastoma, desmoplastic-nodular (Case 4) H&E 4X
Sections of the "posterior fossa mass" show a small round blue cell tumor with extremely high cellularity, cell wrapping, and nuclear molding. Most of these tumor cells appear undifferentiated, with hyperchromatic nuclei and very scant eosinophilic cytoplasm. There are numerous mitotic figures and karyorrhectic debris. Within the sheets of "blue cells," there are "pale" nodular areas where the tumor cells appear differentiated with a fibrillary background and moderate amounts of eosinophilic cytoplasm.
