Meijer O W M, Vandertop W P, Baayen J C, Slotman B J
Department of Radiation Oncology, VU University Medical Center, Amsterdam, The Netherlands.
Int J Radiat Oncol Biol Phys. 2003 Aug 1;56(5):1390-6. doi: 10.1016/s0360-3016(03)00444-9.
In this single-institution trial, we investigated whether fractionated stereotactic radiation therapy is superior to single-fraction linac-based radiosurgery with respect to treatment-related toxicity and local control in patients with vestibular schwannoma.
All 129 vestibular schwannoma patients treated between 1992 and June 2000 at our linac-based radiosurgery facility were analyzed with respect to treatment schedule. Dentate patients were prospectively selected for a fractionated schedule of 5 x 4 Gy and later on 5 x 5 Gy at the 80% isodose in 1 week with a relocatable stereotactic frame. Edentate patients were prospectively selected for a nonfractionated treatment of 1 x 10 Gy and later on 1 x 12.5 Gy at 80% isodose with an invasive stereotactic frame. Both MRI and CT scans were made in all 129 patients within 1 week before treatment. All patients were followed yearly with MRI and physical examination.
A fractionated schedule was given to 80 patients and a single fraction to 49 patients. Mean follow-up time was 33 months (range: 12-107 months). There was no statistically significant difference between the single-fraction group and the fractionated group with respect to mean tumor diameter (2.6 vs. 2.5 cm) or mean follow-up time (both 33 months). Only mean age (63 years vs. 49 years) was statistically significantly different (p = 0.001). Outcome differences between the single-fraction treatment group and the fractionated treatment group with respect to 5-year local control probability (100% vs. 94%), 5-year facial nerve preservation probability (93% vs. 97%), and 5-year hearing preservation probability (75% vs. 61%) were not statistically significant. The difference in 5-year trigeminal nerve preservation (92% vs. 98%) reached statistical significance (p = 0.048).
Linac-based single-fraction radiosurgery seems to be as good as linac-based fractionated stereotactic radiation therapy in vestibular schwannoma patients, except for a small difference in trigeminal nerve preservation rate in favor of a fractionated schedule.
在这项单机构试验中，我们研究了对于前庭神经鞘瘤患者，分次立体定向放射治疗在治疗相关毒性和局部控制方面是否优于基于直线加速器的单次放射外科治疗。
对1992年至2000年6月期间在我们基于直线加速器的放射外科治疗机构接受治疗的129例前庭神经鞘瘤患者的治疗方案进行分析。有齿状患者前瞻性地选择接受5×4 Gy、随后在1周内于80%等剂量线处接受5×5 Gy的分次治疗方案，使用可重新定位的立体定向框架。无齿状患者前瞻性地选择接受1×10 Gy、随后在80%等剂量线处接受1×12.5 Gy的非分次治疗方案，使用侵入性立体定向框架。所有129例患者在治疗前1周内均进行了MRI和CT扫描。所有患者每年进行MRI和体格检查随访。
80例患者接受了分次治疗方案，49例患者接受了单次治疗。平均随访时间为33个月（范围：12 - 107个月）。单次治疗组和分次治疗组在平均肿瘤直径（2.6 vs. 2.5 cm）或平均随访时间（均为33个月）方面无统计学显著差异。仅平均年龄（63岁 vs. 49岁）有统计学显著差异（p = 0.001）。单次治疗组和分次治疗组在5年局部控制概率（100% vs. 94%）、5年面神经保留概率（93% vs. 97%）和5年听力保留概率（75% vs. 61%）方面的结果差异无统计学意义。5年三叉神经保留率的差异（92% vs. 98%）达到统计学意义（p = 0.048）。
对于前庭神经鞘瘤患者，基于直线加速器的单次放射外科治疗似乎与基于直线加速器的分次立体定向放射治疗效果相当，除了在三叉神经保留率方面存在小差异，分次治疗方案更具优势。
