Efficacy of Intensity Modulated Radiation Therapy After Surgery in Early Stage of Esophageal Carcinoma;

Inclusion Criteria: * Stage T2-3N0M0 disease of TESCC patients confirmed by pathology studies who received R0 operations in Cancer Institute \& Hospital，CAMS； * KPS≥70 before radiotherapy; * Did not receive neoadjuvant or adjuvant treatment; * No clear recurrent or metastatic lesions before radiotherapy; * Intensity modulated radiation therapy(IMRT) is accepted; * Regular follow-up. Exclusion Criteria: * Exploratory thoracotomy or palliative surgery; * No clear recurrent or metastatic sites; * Recurrence or metastasis is not certain; * death of no definite cause. * Irregular follow-up;