Authors: Berndt Wowra Alexander Muacevic JörgChristian Tonn
Publish Date: 2009/02/01
Volume: 94, Issue: 1, Pages: 69-
Abstract
Objective A comparison of treatment parameters and quality of clinical outcome in patients with single brain metastases treated with two different technologies for radiosurgery Gamma Knife and CyberKnife Methods Treatment parameters were statistically analyzed Clinical outcome was assessed by matchedpair analysis based on the treatment device differences in dose prescription and the date of the treatment Patients were matched according to their tumor size age gender primary cancer and Radiation Therapy Oncology Group score Survival postradiosurgery local and distant tumor control and complications were analyzed Predictive factors were investigated Results 423 single brain metastases were treated with Gamma Knife and 73 with CyberKnife Tumor volumes were similar The parameters minimum tumor dose maximum tumor dose prescription isodose volume conformality index homogeneity index volume of tissue receiving a dose of 10 Gy or more were significantly larger in Gamma Knife group Sixtythree patients were good matches These showed the same pattern in parameters Concerning the outcome analysis only overall survival differed significantly between groups twice as long with CyberKnife P 003 According to pooled data dose was predictive of local failure whole brain radiation therapy and chemotherapy were predictive of toxicity the Radiation Therapy Oncology Group score was predictive of survival after radiosurgery and date of treatment was predictive of overall survival No factor predicted new brain metastases including whole brain radiation therapy Conclusions The most important result of this study was the finding that the obvious differences in treatmentrelated parameters between Gamma Knife and CyberKnife had no impact on the quality of the clinical outcome after radiosurgery Survival time increased chronologically presumably due to an intensified anticancer therapy in the more recent era of the CyberKnife treatments
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