Optimal waiting period to surgical treatment after neoadjuvant chemoradiotherapy for locally advanced rectum cancer: a retrospective observational study

Abstract

Background: The optimal waiting period after neoadjuvant treatment in patients with locally advanced rectal cancers is still controversial. The literature has different results regarding the effect of waiting periods on clinical and oncological outcomes. We aimed to investigate the effects of these different waiting periods on clinical, pathological, and oncological outcomes.

Methods: Between January 2014 and December 2018, a total of 139 consecutive patients with locally advanced rectal adenocarcinoma, who were treated in the Department of General Surgery at the Marmara University Pendik Training and Research Hospital, were enrolled in the study. The patients were split into three groups according to waiting time for surgery after neoadjuvant treatment: group 1 (n = 51) included patients that have 7 weeks and less (≤ 7 weeks) time interval, group 2 (n = 45) 8 to 10 weeks (8-10 weeks), group 3 (n = 43) 11 weeks and above (11 weeks ≤). Their database records, which were entered prospectively, were analyzed retrospectively.

Results: There were 83 (59.7%) males and 56 (40.3%) females. The median age was 60 years, and there was no statistical difference between the groups regarding age, gender, BMI, ASA score, ECOG performance score, tumor location, and preoperative CEA values. Also, we found no significant differences regarding operation times, intraoperative bleeding, length of hospital stay, and postoperative complications. According to the Clavien-Dindo (CD) classification, severe early postoperative complications (CD 3 and above) were observed in 9 patients. The complete pathological response (pCR, ypT0N0) was observed in 21 (15.1%) patients. The groups had no significant difference regarding 3-year disease-free and 3-year overall survival (p = 0.3, p = 0.8, respectively). Local recurrence was observed in 12 of 139 (8.6%) patients and distant metastases occurred in 30 of 139 (21.5%) patients during the follow-up period. There was no significant difference between the groups in terms of both local recurrence and distant metastasis (p = 0.98, p = 0.43, respectively).

Conclusion: The optimal time for postoperative complications and sphincter-preserving surgery in patients with locally advanced rectal cancer is 8-10 weeks. The different waiting periods do not affect disease-free and overall survival. While long-term waiting time does not make a difference in pathological complete response rates, it negatively affects the TME quality rate.

Keywords: Interval; Locally advanced rectal cancer; Neoadjuvant chemoradiotherapy; Waiting period.