[Meningioma following irradiation for vascular nevus. A case report].

A case of meningioma that developed 37 years after irradiation therapy for vascular nevus of the scalp over the right frontoparietal region was reported. A 49-year-old male was admitted to the hospital of Gifu University on October 26, 1979, because of a generalized seizure. He had been born with a vascular nevus affecting the right frontoparietal scalp, for which he began receiving local irradiation at the age of 12. The total dose was not known because the only source of information regarding this treatment was the patient's memory. From the age of 17, the suffered from occasional attacks of dysesthesia in the left side of his body without consciousness disorder. He otherwise remained well for the intervening 37 years. Upon admission, he had a vascular nevus remaining with post irradiation skin changes over the right frontoparietal region. General and neurological examination were not remarkable. Right carotid angiogram and CT scan disclosed the presence of a right frontal tumor. A right frontotemporal craniotomy was performed on December 4, 1979 and a hard tumor was found firmly attached to the dura and bone at the right site. All visible tumor and involved bone were completely removed without difficulty. Histological examination of the surgical specimen showed the characteristic features of a transitional meningioma. There was no evidence of malignancy in the sections examined. Since Mann et al reported a malignant meningioma following irradiation therapy for optic nerve glioma, there have been many reports, over seventy cases of so-called radiation-induced meningioma. However, a meningioma following irradiation therapy for vascular nevus of scalp or face is exceedingly rare.(ABSTRACT TRUNCATED AT 250 WORDS)