Analysis of treatment outcome and prognostic factor with three-dimensional conformal radiotherapy for thoracic esophageal squamous cell carcinoma

Abstract

Objective To evaluate the impact of gross tumor volume(GTV)on prognosis of three-dimensional conformal radiotherapy(3DCRT)in esophageal carcinoma.Methods From Jan.2004 to Oct.2007,131 stageⅠ-Ⅲb patients with unreseetable esophageal carcinomas who received 3DCRT with 60 Gy/ 30f/6w were analyzed retrospectively.The effectiveness of related prognostic factors on survival was evaluated by univariate and multivariate analyses.Results The following-up rate was 100%.By univariate analysis,the 1-,2-and 3-year local tumor control rates were 71%,64%and 60%for patients with GTV volume≤40 cm3,and 43%,32%and 28%for those with GTV volume>40 cm3(X2=13.16,P=0.000).respectively.The 1-,2-and 3-year local tumor control rates were 67%,59%,59%for T1+2 patients,62%,53%,50%for T3 patients,and 41%,28%,19%for T4 patients,respectively(X2=13.25,P=0.001).The 1-,2-and 3-year survival rates were 78%,53%,46%for patients of GTV volume≤40 cm3 and 45%.27%and 7%for patients of GTV volume>40 cm3(X2=21.55,P=0.000).The 1-,2-and 3-year survival rates were 71%,50%and 39%for patients with T1+2,68%,46%and 25%with T3,and 36%,18%and 15%with T4,repectively(X2=14.35,P=0.001).The 1-,2-and 3-year survival rates for patients with tumor length≤5 cm were 75%,50%and 44%,compared with 53%,35%and 18%with tumor length>5cm(X2=5.99,P=0.014).By multivariate analysis,GTV volume and T stage were likelv to be independent prognostic factors for local tumor control rates(X2=7.07,P=0.008;X2=6.63,P=0.036).Only the GTV volume was associated with the overall survival rate(X2=15.82,P=0.000).Conclusions GTV volume is independent prognostic factor.The larger the GTV volume is,the worse the prognosis will be. Key words: Esophageal neoplasms/radiotherapy; Radiotherapy,three-dimensional comformal; Prognosis