Safety and feasibility of neoadjuvant chemotherapy as a surgical bridge for acute left-sided malignant colorectal obstruction: a retrospective study

Background For colorectal cancer, preoperative (neoadjuvant) chemotherapy is more effective than postoperative chemotherapy because it not only eradicates micrometastases more effectively but also reduces the risk of incomplete intraoperative resection and tumor cell shedding. For the treatment of acute left-sided malignant colorectal obstruction, colorectal stents as well as stoma are being used to relieve the obstructive colorectal cancer, and as a bridge to surgery, allowing easy mobilization and resection of the colon. Neoadjuvant chemotherapy combined with self-expandable metal stents (SEMS) or neoadjuvant chemotherapy combined with decompressing stoma (DS) can be used as a bridge to elective surgery (BTS) as an alternative to emergency surgery in patients with acute left-sided malignant colorectal obstruction, but its benefit is uncertain. The purpose of this study was to evaluate the safety and feasibility of neoadjuvant chemotherapy as a bridge to surgery in the treatment of acute left-sided malignant colorectal obstruction. Methods Data from patients who were admitted with acute left-sided malignant colorectal obstruction between January 2012 and December 2020 were retrospectively reviewed, and patients with gastrointestinal perforation or peritonitis were excluded. We performed one-to-two propensity score matching to compare the stoma requirement, postoperative complications, and other short-term oncological outcomes between the neoadjuvant chemotherapy group and surgery group. Results There were no differences in intraoperative blood loss, operative time, one-year postoperative mortality, and postoperative tumor markers between the two groups. The 1-year recurrence-free survival (RFS) rates of neoadjuvant chemotherapy group and surgery group were 96.8 and 91.3% ( p = 0.562). The neoadjuvant chemotherapy group was able to reduce stoma rate 1 year after surgery ( p = 0.047). Besides, the neoadjuvant group significantly reduced postoperative bowel function time ( p < 0.001), postoperative hospital stay ( p < 0.001), total hospital stay ( p = 0.002), postoperative complications ( p = 0.017), reduction in need to stay in the intensive care unit (ICU) ( p = 0.042). Conclusions Neoadjuvant chemotherapy as a bridge to elective surgery in patients with acute left-sided malignant colorectal obstruction is safe and has many advantages. Prospective multicenter studies with large samples are needed to further evaluate the feasibility of neoadjuvant chemotherapy.