Primitive Neuroectodermal Tumor of the Brain Associated with Malignant Rhabdoid Tumor of the Liver: A Histologic, Immunohistochemical, and Electron Microscopic Study

A 14-day-old white male, born with a large primitive neuroectodermal tumor of the left cerebral hemisphere, was found to have a solitary rhabdoid tumor in the liver incidentally at autopsy. Cells resembling the liver rhabdoid cells were also found by histology, immunohistochemistry, and electron microscopy in the brain tumor. The concurrence of rhabdoid cells in the tumors of the brain and liver suggests a common histogenesis and further supports the previous suggestion that the rhabdoid tumor is of neuroectodermal origin. The rhabdoid tumor in the liver in this case is likely to be a metastatic tumor from the brain rather than a second primary tumor.