High-dose radiation-induced meningiomas.

BACKGROUND: Numerous neoplasms within the CNS have been reported as radiogenic in origin; radiation-induced meningiomas are at least five times more numerous than gliomas or sarcomas in the world literature. METHODS: The authors review 10 cases of cerebral meningiomas following high-dose radiotherapy in patients operated for neoplasm of the nervous system. The pathologic and clinical aspects of this unusual complication are analyzed in all cases in the world literature. RESULTS: There is a female predominance (F-M ratio: 3:2) and the patients are young (mean age: 33.1 years; median: 29 years). The average latency period is 14.4 years (range: 9-21 years). The first disease is acute lymphocytic leukemia (ALL) in 40% of cases. Radiation induced meningiomas are atypical in four cases. Recurrence was observed in one case without malignant transformation. CONCLUSION: High-dose radiation-induced meningiomas have the following characteristics: (1) children appear particularly sensitive to the development of this tumor; (2) there is a female predominance, otherwise than is observed in low-dose meningioma; (3) these tumors present a peak frequency in the third decade of life; and (4) frequently, these tumors are atypical and recur. Finally, it is essential that every new case be reported to throw light on this particular pathologic correlation with its many grey areas.