非小细胞肺癌三维适形放疗放射性肺损伤临床及剂量学因素分析

目的 探讨非小细胞肺癌(NSCLC)根治性三维适形放疗(3DCRT)后放射性肺损伤发生因素.方法 搜集86例接受根治性3DCRT[处方剂量≥60～66 Gy,1.8～2.0 Gy/(次·d),5 d/周]的NSCLC患者资料,对性别、年龄、吸烟史、心脏病史、肺功能、发病部位、临床分期、病理诊断、是否合并化疗等临床因素以及放疗剂量、射野数量、平均肺受量(MLD)、正常肺体积剂量(V_5～V_(65)间隔5 Gy)等剂量学因素与放射性肺损伤之间的关系进行回顾性分析.采用CTC 3.0标准对放射性肺损伤进行分级,单因素及多因素分析筛选预测因素.结果 中位随访期12个月(1～36个月),12例发生≥3级放射性肺损伤.单因素分析V_5～V_(35)MLD等因素与放射性肺损伤有关,而与全部临床因素、放疗剂量、照射野数、V_(40)～V_(65)等无关.筛选单因素分析中有统计学意义的因素进行Logistic回归分析,结果仅V_5是放射性肺损伤发生的独立预后因素(χ~2=5.15,P=0.023).V_5≤45%组放射性肺损伤发病率为2%,V_5>45%组为26%(χ~2=10.24,P=0.001).结论 受照体积可能比受照剂量对放射性肺损伤发生的影响更大.众多剂量学因素与放射性肺损伤发生相关,其中V_5是独立预后因素.

Clinical and dosimetric factors associated with radiation-induced lung damage in patients with non-small cell lung cancer treated with three-dimentional conformai radiotherapy

Objective To investigate the factors associated with radiation-induced lung damage in non-small cell lung cancer (NSCLC) treated with radical three-dimensional conformal radiotherapy (3DCRT). Methods Eighty-six patients with NSCLC were treated by radical 3DCRT (total dose 60-66 Gy, 1.8-2.0 Gy/f, 5 d/w). Several clinical and dosimetric factors were analyzed retrospectively, inclu-ding sex, age, smoking history, heart disease history, pulmonary function, tumor location, clinical stage,pathological diagnosis, chemotherapy, total dose, numbers of fields, mean lung dose (MLD), V_5, V_(10),V_(15), V_(20), V_(25), V_(30), V_(35), V_(40), V_(45), V_50, V_55, V_(60) and V_(65). Radiation-induced lung damage was graded ac-cording to the Common Terminology Criteria for Adverse Events version 3.0. Univariate and multivariate an-alyses were performed to identify the predictive factors. Results The median follow-up was 12 months (range, 1-36 months). The incidence of≥ grade 3 radiation-induced lung damage was 13.9%. In univari-ate analysis, V_5, V_(10),V_(15), V_(20), V_(25), V_(30), V_(35)and MLD were all significantly associated with radiation-induced lung damage, while the clinical factors, total dose, numbers of fields, V_(40), V_(45), V_50, V_55, V_(60)and V_(65) were not. In Logistic regression analysis, Vs was the only factor significantly associated with radiation-induced lung damage (χ~2=5.15,P=0.023). The incidence of ≥ grade 3 radiation-induced lung damage in the group with V_5≤45% and V_5 > 45% were 2.3% and 26.2%, respectively (χ~2= 10.24, P = 0.001). Conclu-sions The lung damage may dependent on the irradiated volume more than the radiation dose. A number of doaimetric factors are significantly associated with radiation-induced lung damage. However , V_5 should be considered in radical 3DCRT for NSCLC patients to reduce the incidence of radiation-induced lung damage.