Primary meningeal rhabdomyosarcoma in a child with hypomelanosis of Ito.

Intracranial rhabdomyosarcomas are rare neoplasms, and those thought to be primary meningeal tumors are even more rare. Hypomelanosis of Ito is a neurocutaneous disorder believed to involve a defect in cells of neural crest origin. We report the case of a 15-month-old boy with hypomelanosis of Ito who developed a primary meningeal rhabdomyosarcoma. The patient initially presented with hydrocephalus and 2 months later developed neurologic signs localizing to the spinal cord. Radiologic studies revealed widespread leptomeningeal enhancement with compression of the spinal cord at C5-C7. A brain biopsy revealed a tumor diffusely involving the meninges. Microscopically, the tumor was composed of rhabdomyoblasts, many of which showed prominent cross-striations on routine hematoxylin-eosin staining. To the best of our knowledge, this is the first reported case of meningeal rhabdomyosarcoma in a patient with hypomelanosis of Ito and the fourth reported case of a primary meningeal rhabdomyosarcoma reported in the world literature.