Published online Sep 15, 2016. doi: 10.4251/wjgo.v8.i9.695
Peer-review started: May 3, 2016
First decision: June 6, 2016
Revised: June 17, 2016
Accepted: July 14, 2016
Article in press: July 18, 2016
Published online: September 15, 2016
To investigate the prognostic effect of a delayed interval between neoadjuvant chemoradiotherapy (CRT) and surgery in locally advanced rectal cancer.
We evaluated 87 patients with locally advanced mid- or distal rectal cancer undergoing total mesorectal excision following an interval period after neoadjuvant CRT at Şişli Hamidiye Etfal Training and Research Hospital, Istanbul between January 2009 and January 2014. Patients were divided into two groups according to the interval before surgery: < 8 wk (group I) and ≥ 8 wk (group II). Data related to patients, cancer characteristics and pathological examination were collected and analyzed.
When the distribution of timing between group I (n = 45) and group II (n = 42) was viewed, comparison of interval periods (median ± SD) of groups showed a significant difference of as 5 ± 1.28 wk in group I and 10.1 ± 2.2 wk in group II (P < 0.001). The median follow-up period for all patients was 34.5 (9.9-81) mo. group II had significantly higher rates of pathological complete response (pCR) than group I had (19% vs 8.9%, P = 0.002). Rate of tumor regression grade (TRG) poor response was 44.4% in group I and 9.5% in group II (P < 0.002). A poor pathological response was associated with worse disease-free survival (P = 0.009). The interval time did not show any association with local recurrence (P = 0.79).
Delaying the neoadjuvant CRT-surgery interval may provide nodal down-staging, improve pCR rate, and decrease the rate of TRG poor response.
Core tip: Delaying the neoadjuvant chemoradiotherapy (CRT)-surgery interval for treatment of locally advanced rectal carcinoma may improve pathological complete response rates by providing nodal down-staging, as well as decreasing the rate of tumor regression grade (TRG) poor response. TRG may be an important predictive factor for disease-free survival. Extending the interval between CRT and surgery may improve the survival through tumor down-staging without increasing the rate of surgical complications.