三维适形放射治疗常规外照射后复发的非小细胞肺癌

3-D conformal radiation therapy for postradiation recurrent non-small cell lung cancer:a clinical phase Ⅰ trial

目的 研究三维适形放射治疗常规放射治疗后复发的非小细胞肺癌可行性 ,观察近期疗效及早期并发症的发生率。方法 2 0 0 0年 10月至 2 0 0 1年 2月 ,12例非小细胞肺癌疗后复发病例 ,由美国CMS公司 2 .6 .1三维治疗计划系统设计放射治疗计划 ,剂量体积直方图 (DVH)评价和优化放射治疗计划 ,体部固定装置及多叶光栏技术实施适形放射治疗。计划靶区为临床所见肿瘤区外放 1.0～ 1.5cm ,计划照射剂量为 4 0～ 6 0Gy ,2 .5～ 3.0Gy/次 ,1次 /d ,5d/周。照射方法为固定野、非共面野或旋转弧。计划靶区体积 (PTV)中位体积为 2 95cm3 (76 .4～ 5 12 .4cm3 )。按美国放射肿瘤学协作组(RTOG)和世界卫生组织 (WHO)标准观察急性放射反应及近期疗效。结果 12例患者均顺利完成治疗。初次放射治疗至再放射治疗的中位间隔时间为 19个月 (12～ 32个月 ) ,再放射治疗肿瘤中位剂量5 1.2Gy(42 .0～ 6 7.5Gy)。近期疗效为完全缓解 (CR) 8.3% (1/12 ) ,部分缓解 (PR) 6 6 .7% (8/12 ) ,无变化 (NR) 2 5 .0 % (3/12 ) ,进展 (PD) 0 % (0 /12 ) ,总有效率为 75 .0 % (9/12 )。根据RTOG分级 ,急性放射性食管炎发生率 1～ 2级 16 .7% (2 /12 ) ,3级 0 % (0 /12 ) ;急性放射性肺炎发生率 1～ 2级 16 .7% (2 /12 ) ,3级 0 % (0

Objective To evaluate the feasibility of reirradiation for postradiation recurrent non small cell lung cancer(NSCLC) using 3 dimensional conformal radiotherapy (3 D CRT) and to assess the immediate responses and acute side effects.Methods Between Oct. 2000 and Feb. 2001,12 NSCLC patients with local recurrence after their initial radiotherapy received retreatment with 3 D CRT. Radiotherapy was designed by the US CMS 2.6.1 3 D treatment planning system and dose volume histography (DVH) was used to verify and optimize the radiation plan. Multileaf collimation technique and immobilization devices for treatment position were used to achieve validity and accuracy of radiotherapy. The planning target volume (PTV) encompassed 1.0 1.5?cm safety margin beyond the clinical target volume (CTV). The total irradiation dose, ranging from 40 Gy to 60 Gy ,was delivered at 2.5 3.0 Gy once daily,5 days per week. The median PTV volume was 295 cm 3 (range:76.4 512.4 cm 3). The immediate responses and acute side effects were evaluated according to the WHO and RTOG criterion system. Results All 12 patients completed their second course radiotherapy. The median period between the courses was 19 months(12 32). The median radiation therapy dose to the gross tumor volume(GTV) was 51.2?Gy(42.0 67.5?Gy). The overall immediate response rate(CR+PR) was 75.0%(9/12).According to the RTOG criterion,Grade 1 2 acute radiation esophagitis occurred in 16.7%(1/12) and Grade 1 2 acute radiation pneumonitis occurred in 16.7%(2/12) patients.Grade 1 2 bone marrow suppression occurred in 8.3%(1/12) of patients and Grade 1 2 myocardial injury was present in 16.7% (2/12) of patients. The median follow up duration was 5 months.Conclusions 3 D conformal radiotherapy can be considered as an effective and feasible approach to re treat postradiation local recurrence of NSCLC with good responses and without any early serious complications. Long term survival and possible specific injury should await further study.