Primary intracranial rhabdomyosarcoma producing proptosis.

A case is reported of a primary rhabdomyosarcoma occurring in the right subfrontal region of a 16 year old girl. The patient suffered from dull frontal headache and proptosis for three months before hospitalization. The circumscribed and demarcated neoplasm involved the dura mater, and invaded the frontal sinus and roof of the orbit on the same side. The pathogenesis of the tumour is thought to be related to aberrant differentiation of unstable mesenchyme. A suggestion is made that the "medullomyoblastoma" should be classified as a type of neoplasm of mixed mesenchymal and neuroepithelial origin.