Time interval between neoadjuvant radiation therapy and surgery and overall survival of rectal cancer patients

Aim: To investigate the association of time interval between neoadjuvant RT and surgery (RS-interval) with pathological complete response (pCR) and overall survival (OS) of rectal cancer patients. Methods: We used the National Cancer Database and reported Odds ratios (OR) and Hazard ratios. Results: Patients with an RS-interval of 5–24 weeks were more likely to achieve pCR compared with ≤4 weeks. RS-interval of 13–24 weeks was associated with a reduced OS compared with ≤4 weeks only in patients who did not achieve pCR. Conclusion: RS-interval of 5–8, 9–12, 13–16, 17–20, or 21–24 weeks was associated with a higher likelihood of achieving pCR compared with ≤4 weeks. In patients without pCR, delaying surgery >12 weeks was associated with reduced OS.