Variables and definitions

Collected data included patient demographic characteristics, clinical and pathologic stages of the tumor, tumor location, treatment regimen, duration and completion date of neoadjuvant CRT, type of surgical procedure, completeness of the resection, and postoperative pathologic data. Patients were divided into 4 groups according to the time interval between the completion of preoperative radiotherapy and surgery: 5–7 weeks (35–48 days), 7–9 weeks (49–62 days), 9–11 weeks (63–6 days), and >11 weeks (>77 days). The primary outcome was the rate of pCR (ypT0N0), and secondary outcomes were tumor downstaging (ypT<cT), node downstaging (ypN<cN), TN downstaging (ypTN<cTN), and 3-year overall survival. Patients with ypT0-1 were defined as good responders to preoperative CRT. Overall survival was based on death due to any cause.