[Amplification of L-myc oncogene in malignant meningioma. Case report]

Amplification of L-myc oncogene was noticed in a malignant meningioma originating from the right sphenoidal wing of a 54-year-old female. The patient underwent three surgical resections plus radiotherapy over a period of 11 years and then the growth rate of the tumor became much greater with a severely invasive appearance. Using Southern blot hybridization, L-myc amplification was examined on the specimen resected at the fourth operation. As a result, approximately five-fold amplification was confirmed, which has not been previously reported except for that in a small cell carcinoma of the lung. This result may suggest that L-myc amplification is responsible to some extent for the malignant transformation in this meningioma.