Primitive cerebral neuroectodermal tumor with rhabdomyoblastic differentiation.

A case is presented of a primitive neuroectodermal tumor located in the left frontal cerebrum, which demonstrated electron microscopic and immunocytochemical evidence of rhabdomyoblastic differentiation. Within the group of supratentorial primitive neuroectodermal tumors, only medulloepithelioma has previously been shown to manifest "divergent" differentiation. In several respects our case is analogous to infratentorial "medullomyoblastoma."