Abstract: ObjectiveTo explore the prognosis and the related factors in T4 esophageal carcinoma with three-dimensional conformal radiotherapy (3D-CRT). MethodsOne hundred and thirty patients with esophageal cancer were treated with 3D-CRT with total irradiation dose of 50~76 Gy. Gender, age, location of primary tumor, the different bite, the lesion length in barium esophagogram, the largest diameter of lesion in CT scanning image, metastasis of lymph node, M stage, dose of irradiation, chemotherapy and recent efficacy were used as analysis factors for Cox regression univariate and multivariate analysis. ResultsAfter radiotherapy, CR was in 34, PR in 83 and NR in 13 patients; and the rate of total efficiency(CR+PR) was 90%. 1-,3-and 4-year survival rates and median was 57.69%, 22.73%, 16.92% and 14.2 months, respectively. With univariate analysis, location of primary tumor, the different bite, the lesion length in barium esophagogram, the largest diameter of lesion in CT scanning image, metastasis of lymph node or organ, and recent efficacy were related with prognosis of esophaeal cancer after 3D-CRT (P<0.05); but gender, age, dose of irradiation and chemotherapy were not related with prognosis of esophaeal cancer(P>0.05). With multivariate analysis, location of primary tumor, different bite, lesion length in barium esophagogram, metastasis of lymph node and M stage were independent prognostic factors. ConclusionFor patients at T4 stage esophageal cancer with 3D-CRT, the main prognostic factors were location of primary tumor, different bite, the lesion length in barium esophagogram, metastasis of lymph node and M stage.