Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, Indiana; Indiana University Health Proton Therapy Center, Bloomington, Indiana.
Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, Indiana.
Int J Radiat Oncol Biol Phys. 2015 Feb 1;91(2):261-7. doi: 10.1016/j.ijrobp.2014.10.011.
We evaluated patient and treatment parameters correlated with development of temporal lobe radiation necrosis.
This was a retrospective analysis of a cohort of 66 patients treated for skull base chordoma, chondrosarcoma, adenoid cystic carcinoma, or sinonasal malignancies between 2005 and 2012, who had at least 6 months of clinical and radiographic follow-up. The median radiation dose was 75.6 Gy (relative biological effectiveness [RBE]). Analyzed factors included gender, age, hypertension, diabetes, smoking status, use of chemotherapy, and the absolute dose:volume data for both the right and left temporal lobes, considered separately. A generalized estimating equation (GEE) regression analysis evaluated potential predictors of radiation necrosis, and the median effective concentration (EC50) model estimated dose-volume parameters associated with radiation necrosis.
Median follow-up time was 31 months (range 6-96 months) and was 34 months in patients who were alive. The Kaplan-Meier estimate of overall survival at 3 years was 84.9%. The 3-year estimate of any grade temporal lobe radiation necrosis was 12.4%, and for grade 2 or higher radiation necrosis was 5.7%. On multivariate GEE, only dose-volume relationships were associated with the risk of radiation necrosis. In the EC50 model, all dose levels from 10 to 70 Gy (RBE) were highly correlated with radiation necrosis, with a 15% 3-year risk of any-grade temporal lobe radiation necrosis when the absolute volume of a temporal lobe receiving 60 Gy (RBE) (aV60) exceeded 5.5 cm(3), or aV70 > 1.7 cm(3).
Dose-volume parameters are highly correlated with the risk of developing temporal lobe radiation necrosis. In this study the risk of radiation necrosis increased sharply when the temporal lobe aV60 exceeded 5.5 cm(3) or aV70 > 1.7 cm(3). Treatment planning goals should include constraints on the volume of temporal lobes receiving higher dose. The EC50 model provides suggested dose-volume temporal lobe constraints for conventionally fractionated high-dose skull base radiation therapy.
我们评估了与颞叶放射性坏死发展相关的患者和治疗参数。
这是对 2005 年至 2012 年间接受颅底脊索瘤、软骨肉瘤、腺样囊性癌或鼻窦恶性肿瘤治疗的 66 例患者队列的回顾性分析，这些患者至少有 6 个月的临床和影像学随访。中位放疗剂量为 75.6Gy（相对生物效应[RBE]）。分析的因素包括性别、年龄、高血压、糖尿病、吸烟状况、化疗的使用以及左右颞叶的绝对剂量-体积数据。广义估计方程（GEE）回归分析评估了放射性坏死的潜在预测因素，而中位有效浓度（EC50）模型估计了与放射性坏死相关的剂量-体积参数。
中位随访时间为 31 个月（范围 6-96 个月），存活患者的中位随访时间为 34 个月。3 年总生存率的 Kaplan-Meier 估计值为 84.9%。3 年任何级别颞叶放射性坏死的估计值为 12.4%，2 级或更高放射性坏死的估计值为 5.7%。在多变量 GEE 中，只有剂量-体积关系与放射性坏死的风险相关。在 EC50 模型中，从 10 到 70Gy（RBE）的所有剂量水平都与放射性坏死高度相关，当颞叶接受 60Gy（RBE）的绝对体积（aV60）超过 5.5cm3 时，3 年内任何级别的颞叶放射性坏死的风险为 15%，或者 aV70>1.7cm3。
剂量-体积参数与发生颞叶放射性坏死的风险高度相关。在本研究中，当颞叶 aV60 超过 5.5cm3 或 aV70>1.7cm3 时，放射性坏死的风险急剧增加。治疗计划目标应包括限制颞叶接受更高剂量的体积。EC50 模型为常规分割高剂量颅底放射治疗提供了颞叶剂量-体积限制建议。
