Acute esophageal toxicities in patients with stage Ⅲ non-small cell lung cancer treated by three-dimensional conformal radiotherapy combined with concurrent chemotherapy / 中华放射肿瘤学杂志

ABSTRACT

Objective To investigate the radiation-induced esophageal toxicities in Ⅲ stage non-small cell lung cancer (NSCLC) treated by three-dimensional conformal radiotherapy (3DCRT) combined with concurrent chemotherapy, and to find the relevant predictive factors. Methods From September 2006 to October 2007, 37 patients with stage Ⅲ NSCLC were treated by 3 DCRT (60 Gy in 30-34 fractions) con-currently with navelbine and cisplatin (NP). Chemotherapy was given in the first and fifth week. Univariate and multivariate analyses and receiver operating characteristic curves (ROC) were used to assess the associ-ation of radiation-induced esophagitis and correlated factors. Results Of all the patients, 91.89% (34/37) developed radiation-induced esophagitis, including grade 1 in 11 patients, grade 2 in 9, grade 3 in 14 and grade 4 in none. According to Spearman correlative analysis, the correlative factors included mean esophagus dose (MED), the LETT_(40)、LETT_(45)、LETT_(50)、LETT_(55)、LETT_60)of esophagus.All the 11 factors had good correlation with esophagitis in univariate analysis, while only V_55 was independ-ently associated with esophagitis in multivariate analysis. The ROC analysis indicated that the cut-off point of the curve was 30% with the area under ROC curve of 0.906, (P=0.000). Grade 2 or 3 radiation esophagi-tis occurred in all the patients with esophageal V_55 > 30%, while only in 36% ( 8/22 ) of those with V_55<30%. Conclusions 3DCRT combined with concurrent chemotherapy in patients with stage Ⅲ NSCLC could develop severe esophagitis. Dosimetric parameters (MED, LETT_(40),LETT_(45),LETT_(50),LETT_(55),LETT_(60),V_(40),V_(45),V_50,V_55,V_(60))are related with esophagitis,V_55 with V_55 > 30% being the most valuable predictor.