Elective nodal irradiation is not necessary in chemoradiotherapy for postoperative loco-regional recurrent esophageal cancer

Purpose: The purposes of the present study were to evaluate prognostic factors for patients with postoperative loco-regional recurrent esophageal cancer treated with chemoradiotherapy by multivariate analysis and to determine which irradiation is better, involved field irradiation or elective nodal irradiation, by matched-pair analysis. Methods: We reviewed records for 80 patients with postoperative loco-regional recurrent esophageal cancer treated by chemoradiotherapy between 2000 and 2014. The median follow-up period was 62.0 months. Thirty-one cases were treated with elective nodal irradiation and were randomly matched by risk factors to 49 cases treated with involved field irradiation (1:1). Results: Fifty-one patients had disease recurrence again, and irradiated-field failure was observed in 26 patients. The 5-year overall survival rate was 30.5% with a median survival period of 26.5 months. Grade 3 or higher late toxicity was observed in only one patient. In multivariate analysis, short disease-free interval and anastomotic recurrence were statistically significant unfavorable prognostic factors for overall survival (hazard ratios: 2.1 and 2.5, respectively). Matched-pair analysis including disease-free interval, pattern of recurrence and number of recurrent regions revealed that overall survival rate and irradiated-field control rate in patients treated with involved field irradiation were significantly better than those in patients treated with elective nodal irradiation (P = 0.016 and P = 0.014, respectively). Conclusions: Short disease-free interval and anastomotic recurrence are unfavorable factors and elective nodal irradiation is not necessary in chemoradiotherapy for patients with postoperative loco-regional recurrent esophageal cancer.