Waiting Time following Neoadjuvant Chemoradiotherapy for Rectal Cancer: Does It Really Matter.

Background: Neoadjuvant chemoradiotherapy (CRT) is considered the standard approach before any surgical intervention for locally advanced rectal tumors and has been proven to significantly improve the local recurrence rates of rectal cancer. However, the optimal timing of surgical resection after neoadjuvant CRT remains debatable.

Objective and methods: We conducted a retrospective review of 65 consecutive patients with locally advanced rectal cancer who underwent preoperative CRT followed by surgical resection in order to evaluate the optimal time for surgical treatment. We used two alternative groups for analysis: patients who underwent surgery up to 6 weeks after CRT (n = 28) and those who underwent surgery 6 weeks or more after CRT (n = 27). Also, we compared patients who were operated on within 3 months (n = 39) with those who underwent surgical resection after more than 3 months (n = 16). Nonresponders to CRT were excluded from the analysis.

Results: There was no statistically significant association between waiting period post CRT and radiological downstaging for any group (p > 0.05 for any association). Also, there was no association between recurrence of disease, cancer-related deaths, perineural invasion, or positive lymph node ratio and any waiting period up to 3 months (p > 0.05 for all associations).

Conclusion: In this small exploratory study there was no evident difference in outcome according to timing of surgery, which suggests that further research in larger cohorts is warranted.