Differences in clinical outcomes according to the time interval between the bridge to surgery stenting and surgery for left-sided malignant colorectal obstruction

Background Self-expandable metal stent (SEMS) placement is commonly used as a bridge to surgery (BTS) for left-sided malignant colorectal obstruction (MCO). However, the optimal time interval between BTS stenting and surgery for left-sided MCO is unclear, and the results of previous studies are conflicting. This study aimed to determine the differences in clinical outcomes according to the time interval between BTS stenting and surgery in left-sided MCO. Methods Data from 594 patients who underwent SEMS placement for MCO between January 2009 and December 2018 were reviewed. Among them, 148 patients who underwent SEMS placement as BTS treatment and curative surgery were enrolled. The enrolled patients were divided into three groups according to the interval between BTS stenting and surgery: group 1 (interval ≤2 weeks), group 2 (interval 2–3 weeks), and group 3 (interval >3 weeks). Results Group 2 and 3 patients underwent significantly higher rates of laparoscopic surgery than those in group 1 (83.7, 81.0 vs. 53.2 %, respectively; P =0.003, P =0.003, respectively). Also, rates of stoma formation directly after resection were significantly higher in group 1 compared to groups 2 and 3 (21.3 vs 2.3, 6.9%, respectively; P =0.008, P =0.043, respectively). Bridging interval had no effect on SEMS-related complications, resection-related complications, 90-day mortality, permanent stoma formation, 3-year disease-free survival, and 3-year overall survival. Conclusions A bridging interval of > 2 weeks between BTS stenting and surgery for left-sided MCO is preferable for lower stoma formation rates and higher rates of laparoscopic approach operation, with no difference in short-term and long-term outcomes including complication, mortality, and survival.