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

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 251 patients with resected TESCC underwent 3DCRT or IMRT at the Cancer Hospital (Institute), Chinese Academy of Medical Sciences between 2004. 1 to 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 method was 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 to 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 (χ2 = 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 (χ2 =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 (χ2 =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 (χ2 = 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 of intrathoracic recurrence. Five patients had grade 2 or 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 III TESCC or TESCC with lymph node metastasis. (authors)