Patterns of failure after salvage chemoradiotherapy for postoperative loco-regional recurrent esophageal cancer: 20-year experience in a single institution in Japan

Purpose The purpose of the present study was to evaluate patterns of recurrence after salvage chemoradiotherapy (SCRT) for postoperative loco-regional recurrent esophageal cancer. Methods We reviewed records for 114 patients with postoperative loco-regional recurrent esophageal cancer treated by platinum-based chemoradiotherapy between 2000 and 2020, and we evaluated the patterns of failure in patients who had recurrence again or who had been observed for 2 years or more after SCRT at the last observation date. Results One hundred and three patients were enrolled in this study. The median observation period for survivors was 60 months. Fifty-three patients died of esophageal cancer and nine patients died of other diseases. The 5-year overall survival rate, cause-specific survival rate and disease-control rate were 43.7%, 45.3% and 37.0%, respectively. Sixty-five patients had failure after SCRT. In those patients, 26 patients had only distant organ or non-regional lymph node metastases, 26 patients had only loco-regional failure, and 13 patients had both. Of those 65 patients, 64 patients showed failure within 42 months after SCRT. Of 39 patients with loco-regional failure, failure in the irradiated field was observed in 28 patients. Of those 28 patients, 27 patients showed failure within 24 months and the other patient showed failure at 26.5 months. Conclusions The patterns of failure after SCRT for patients with postoperative loco-regional recurrent esophageal cancer were shown. The patterns of failure suggest that follow-up for at least 4 years after SCRT should be performed for those patients.