RESUMO
Objective To explore the incidence and related predictive factors for acute symptomatic esophagitis in patients with locally advanced non?small cell lung cancer ( NSCLC ) treated with intensity?modulated radiation therapy ( IMRT) . Methods Data were collected retrospectively from 256 patients with inoperable or unresectable stage Ⅲ NSCLC treated in our hospital between January 2007 and December 2011. The radiotherapy target volume included primary lung cancer and lymphatic drainage area involved,with a median dose of 60 Gy in 30 fractions (50-70 Gy).Of all the patients,109 patients (42.6%) received concurrent chemotherapy. Grade ≥2 acute esophagitis ( AE ) ( symptomatic esophagitis ) which occurred during radiotherapy and within 3 months after completion of radiotherapy served as the outcome event. National Cancer Institute Common Terminology Criteria for Adverse Events version 3.0( NCI?CTCAE3.0) was used to evaluate the grade of AE. The logistic regression model was used to analyze the predictive factors. Results A total of 174 patients ( 68%) had treatment?related grade ≥2 AE;154 patients ( 60. 2%) had grade 2 AE and 20 patients (7.8%) had grade 3 AE.The median dose when grade≥2 AE occurred was 30 Gy (11?68 Gy).For grade≥2 AE,multivariate analysis showed that esophageal V5?V60,mean dose,and age were independent predictive factors (P=0.021,0,0.010).For grade ≥3 AE,multivariate analysis showed that esophageal V50?V60 ,concurrent chemotherapy,and body mass index ( BMI) were independent predictive factors ( P= 0.010,0.003,0.019 ) . Old age and higher BMI were the protective factors for grade≥2 and ≥3 AE, respectively. Conclusions For patients with locally advanced NSCLC treated with IMRT, esophageal V50—V60 and concurrent chemotherapy are predictive factors for grade ≥3 AE,and esophageal V50 has a high predictive value for both grade ≥2 and ≥3 AE.