OBJECT: In this study, the authors evaluate the long-term results after Gamma Knife radiosurgery of cranial base meningiomas. This study is a follow-up to their previously published report on the early results. METHODS: Between January 1994 and December 2001, the authors treated benign cranial base meningiomas in 108 patients using low-dose Gamma Knife radiosurgery. The tumor volumes ranged from 1.7 to 55.3 cm3 (median 8.1 cm3), and the radiosurgery doses ranged from 8 to 12 Gy (median 12 Gy) to the tumor margin. RESULTS: The mean duration of follow-up was 86.1 months (range 20-144 months). Tumor volume decreased in 50 patients (46%), remained stable in 51 patients (47%), and increased (local failure) in 7 patients (6%). Eleven patients experienced tumor recurrence outside the treatment field. Among these patients, marginal failure was seen in 5 and distant recurrence was seen in 6. Seven patients were thought to have malignant transformation based on histological or radiological characteristics of the lesion. The actuarial progression-free survival rate, including malignant transformation and outside recurrence, was 93% at 5 years and 83% at 10 years. Neurological status improved in 16 patients (15%). Permanent radiation injury occurred in 7 patients (6%). CONCLUSIONS: Gamma Knife radiosurgery is a safe and effective treatment for cranial base meningiomas as demonstrated with a long-term follow-up period of > 7 years. Surgeons must be aware of the possibility of treatment failure, defined as local failure, marginal failure, and malignant transformation; however, this may be the natural course of meningiomas and not related to radiosurgery.
OBJECT: In this study, the authors evaluate the long-term results after Gamma Knife radiosurgery of cranial base meningiomas. This study is a follow-up to their previously published report on the early results. METHODS: Between January 1994 and December 2001, the authors treated benign cranial base meningiomas in 108 patients using low-dose Gamma Knife radiosurgery. The tumor volumes ranged from 1.7 to 55.3 cm3 (median 8.1 cm3), and the radiosurgery doses ranged from 8 to 12 Gy (median 12 Gy) to the tumor margin. RESULTS: The mean duration of follow-up was 86.1 months (range 20-144 months). Tumor volume decreased in 50 patients (46%), remained stable in 51 patients (47%), and increased (local failure) in 7 patients (6%). Eleven patients experienced tumor recurrence outside the treatment field. Among these patients, marginal failure was seen in 5 and distant recurrence was seen in 6. Seven patients were thought to have malignant transformation based on histological or radiological characteristics of the lesion. The actuarial progression-free survival rate, including malignant transformation and outside recurrence, was 93% at 5 years and 83% at 10 years. Neurological status improved in 16 patients (15%). Permanent radiation injury occurred in 7 patients (6%). CONCLUSIONS: Gamma Knife radiosurgery is a safe and effective treatment for cranial base meningiomas as demonstrated with a long-term follow-up period of > 7 years. Surgeons must be aware of the possibility of treatment failure, defined as local failure, marginal failure, and malignant transformation; however, this may be the natural course of meningiomas and not related to radiosurgery.
Authors: Elena Vera; J Bryan Iorgulescu; Daniel M S Raper; Karthik Madhavan; Brian E Lally; Jacques Morcos; Samy Elhammady; Jonathan Sherman; Ricardo J Komotar Journal: J Neurol Surg B Skull Base Date: 2014-03-12
Authors: Leland Rogers; Igor Barani; Marc Chamberlain; Thomas J Kaley; Michael McDermott; Jeffrey Raizer; David Schiff; Damien C Weber; Patrick Y Wen; Michael A Vogelbaum Journal: J Neurosurg Date: 2015-01 Impact factor: 5.115
Authors: Matthew R Reynolds; Ammar H Hawasli; Rory K J Murphy; Wilson Z Ray; Joseph R Simpson; Robert E Drzymala; Keith M Rich Journal: J Spine Neurosurg Date: 2013-02-01