Esophageal cancer patients' survival after complete response to definitive chemoradiotherapy: a retrospective analysis

Background Chemoradiotherapy is an alternative to surgery for esophageal cancer, with a putatively equivalent outcome. However, disease recurrence after a complete response is common and if follow-up surveillance detects recurrence, salvage treatments for potentially curable disease must follow. Methods We conducted a nation-wide questionnaire survey of institutions in Japan certified by the Japanese Esophageal Society to investigate outcomes of primary thoracic esophageal cancer patients initially treated by chemoradiotherapy with complete response diagnoses. The primary endpoint was overall survival, the secondary endpoint disease recurrence. Outcomes of patients who had undergone salvage treatments were also investigated. Cases were excluded from analysis if endoscopic study, endoscopic biopsy, or computed tomography data were lacking. Results At 41 institutes 544 case records were collected; valid data on 392 patients were obtained; 5-year survival was 74.8%, 5-year disease-free survival, 66.8%. Clinical staging before treatment significantly affected both overall and disease-free survival rates, but differences between adjoining stages were unexpectedly small. The primary relapse site was classified as primary site (n = 58), regional lymph nodes (n = 36), or distant disease (n = 34). Salvage treatments with curative intent (surgery, endoscopic treatments, and additional radiation) were performed on 38, 23, and 4 cases; 5-year survival after esophagectomy (n = 22), endoscopic treatment (n = 23), and lymphadenectomy (n = 9) was 47.4%, 70.9%, and 33.3%, respectively. Conclusions A quarter of patients developed recurrent disease, mostly locoregional, after complete response. Complete response patients with originally advanced stage disease had fair clinical outcomes; salvage treatments after locoregional recurrence achieved modest long-term survival.