A efficacy analysis of intensity-modulated radiotherapy or three-dimensional conformal radiotherapy for resected thoracic esophageal squamous cell carcinoma

Abstract

Objective To analyze retrospectively the clinical therapeutic effect and toxicities of three-dimensional conformal radiotherapy ( 3DCRT) or intensity modulated radiotherapy ( IMRT) for resected stage Ⅱ/Ⅲ thoracic esophageal squamous cell carcinoma ( TESCC). Methods A total of 251patients with resected TESCC underwent 3DCRT or IMRT at the Cancer Hospital ( Institute) , Chinese Academy of Medical Sciences between 2004. 1 t0 2009. 7 enrolled. Postoperative radiotherapy applied via 3DCRT ( 20 patients) or IMRT (231 patients) with a median total dose of 60 Gy. The Kaplan-Meier methodwas used to calculate the survival rates, and the log-rank test was used for univariate analysis. The Cox proportional model was used for multivariate analysis. Results The follow-up rate was 98. 8％ . 159 and 57 patients were followed t0 3 and 5 years, respectively. The 1-, 3-and 5-year overall survival ( OS) rates for all the patients were 90. 8％ , 56. 1％ and 45. 8％ , respectively. For the stage Ⅱa, Ⅱb, and Ⅲ stage patients , the 5-year OS rates were 65. 0％ , 53. 8％ and 38. 4％ , respectively ( X2 = 7. 30 , P = 0. 026) . The 5-year OS rates were 64. 9％ and 40. 4％ for the patients with negative and positive lymph node metastasis ( X2 =7. 04 , P = 0. 008 ) . Univariate analysis showed that the significant prognostic factors include UICC 2002 stage, the degree of differentiation, lymphatic metastasis and vascular carcinomatous thrombus ( X2 =7. 30 ,7. 04 , 8. 34 ,9. 40 , P = 0. 026 , 0. 008 , 0. 004 ,0.002 ) . Multivariate analysis revealed that the grade of differentiation, lymphatic metastasis and vascular carcinomatous thrombus were independent prognostic factors ( X2 = 6. 86, 5. 27, 4. 24, P= 0. 009, 0. 022, 0. 040 ). Treatment failure occurred in 58 patients because of systemic metastases , 14 cervical lymph node recurrence , 17 abdominal lymph node metastases, and 31 0f intrathoracic recurrence. Five patients had grade 2 0r worse late treatment-related anastomotic stenosis , and 8 patients died from late treatment-related gastrointestinal bleeding. Conclusions Postoperative prophylactic 3DCRT or IMRT of TESCC can provide a favorable local control rate and acceptable toxicity. Postoperative radiotherapy should be included into the standard treatment of Stage ⅢTESCC or TESCC with lymph node metastasis. Key words: Esophageal neoplasms/surgery; Intensity-modulated radiotherapy,postoperative; Three-dimensional conformal radiotherapy,postoperative; Prognosis