非小细胞肺癌伽玛刀治疗后并发放射性肺不张分析

An analysis of radiotherapy-induced alelectasis complicated stereotactic body radiation therapy(body gamma-knife)for patients with medically inoperable non-small-cell lung cancer

目的:回顾分析伽玛刀大分割适形放射治疗非小细胞肺癌(non small cell lung cancer,NSCLC)后并发非肿瘤性肺不张的原因,进一步完善大分割适形放射治疗。方法:488例非小细胞肺癌(NSCLC)分为中央型(262例)和周围型(226例),分别进行了伽玛刀分次治疗,剂量3Gy-8Gy/次,处方剂量50%-70%剂量线,1次/日,5次/周,连续照射,总次数5-16次,总剂量35Gy-60Gy。结果:非小细胞肺癌中央型伽玛刀治疗3-6月后共出现20例放射性肺不张,而周围型未出现放射性肺不张,两组差异明显。结论:放射性肺不张是肺癌大分割适形放射治疗中很少报道的严重并发症,区分中央型和周围型分别实施治疗可能有效减轻治疗的严重并发症,中央型肺癌进行精确放疗时有必要将1,2级支气管作为剂量限制性器官。

Objective：By retrospective analysis of radiotherapy-induced alelectasis complicated stereotactic body radiation therapy（body gamma-knife）for patients with medically inoperable non-small-cell lung cancer,to improve the methed of high-dose conformal radiotherapy.Methods： A total of 488 medically inoperable patients with biopsy-confirmed non-small-cell lung cancer（NSCLC） included peripheral tumor（226 patients）and centre tumor（262 patients）,underwent treatment prospectively using the stereotactic gamma-ray whole-body therapeutic system（body gamma-knife radiosurgery）.A total dose of 35 to 60 Gy was delivered at 3 to 8 Gy/fraction to the 50% to 70% isodose line covering the planning target volume,one fraction one day and five fraction one week.Results： Three to six months after treatment,there were twenty cases of radiation therapy-induced atelectasis occurred in centre tumor and no one occurred in peripheral tumor,there was significant difference between patients with peripheral VS central tumors.Conclusion： Radiation therapy-induced alelectasis is a significant clinical complication of dose escalation for lung cancer.Based on our study results,the high-dose conformal radiotherapy should be used more carefully for patients with central tumors than for peripheral tumor due to excessive toxicity.It＇s necessaary to make grade 1 and 2 bronnchus as a dose-limited oragn for patients with medically inoperable non-small-cell lung cancer theating by stereotactic body radiation therapy.