Association of intervals between neoadjuvant chemoradiation and surgical resection with pathologic complete response and survival in patients with esophageal cancer

Importance: Pathologic complete response (pCR) after neoadjuvant chemoradiotherapy (CRT) may be a clinical prognostic marker of superior outcomes. In patients with esophageal cancer, pCR is associated with increased survival. While mechanisms for increasing the likelihood of pCR remain unknown, in other solid tumors, higher rates of pCR have been associated with longer time intervals between CRT completion and surgical procedures. Objective: To determine the association between time intervals from the completion of CRT to surgical procedure with rates of pCR in patients with esophageal cancer. Design, Setting, and Participants: A prospectively maintained multidisciplinary foregut database was reviewed for consecutively enrolled patients with esophageal cancer from January 2000 to July 2015 presenting for surgical evaluation at a single National Cancer Institute-designated cancer center within a quaternary academic medical center. Interventions: Included patients successfully completed neoadjuvant CRT followed by esophagectomy. Main Outcomes and Measures: Rate of pCR by logistic regression based on a categorized time interval (ie, 0 to 42, 43 to 56, 57 to 70, 71 to 84, 85 to 98, and 99 or more days) from the completion of CRT to surgical resection, adjusted for clinical stage, demographic information, and CRT regimen. Results: Of the 234 patients who met inclusion criteria, 191 (81.6%) were male, and the median (range) age was 64 (58-70) years; 206 (88.0%) were diagnosed as having adenocarcinoma, and 65 (27.9%) had a pCR. Patients in the 85 to 98-day group had significantly increased odds of a pCR compared with other groups (odds ratio, 5.46; 95%CI, 1.16-25.68; P = .03). No significant differences in survival were seen between time groups overall or among patients with residual tumor. Conclusions and Relevance: This study suggests that a time interval of 85 to 98 days between CRT completion and surgical resection is associated with significantly increased odds of a pCR in patients with esophageal cancer. No adverse association with survival was detected as a result of delaying resection, even in patients with residual tumor.