A quasi-bridge to surgery approach for stage IV obstructive colon cancer: extending the bridge-to-surgery concept to metastatic disease.

backgroundThe optimal management of stage IV colorectal cancer with malignant large bowel obstruction remains controversial. Self-expandable metallic stents are an established bridge to surgery in non-metastatic disease, but the role of primary tumor resection after stent placement in stage IV patients is unresolved. We propose and evaluate a "quasi-bridge to surgery" (Quasi-BTS) strategy in which stenting serves as a biological selection tool to identify patients who may benefit from delayed primary tumor resection.

methodsThis single-center retrospective cohort study analyzed consecutive stage IV obstructive colorectal cancer patients who underwent successful self-expandable metallic stent placement between January 2007 and December 2023. Patients were categorized into a Quasi-BTS group (delayed primary tumor resection), a palliative chemotherapy-only group, and palliative care-only group. Primary outcomes were overall survival, stent-related complications, and stoma-free survival.

resultsFifty-three patients were analyzed (Quasi-BTS, n = 16; palliative chemotherapy only, n = 22; palliative care only, n = 15). The Quasi-BTS group had zero overall stent-related complications versus 46.7% and 36.4% in the palliative care-only and palliative chemotherapy-only groups, respectively (P = 0.009); perforation alone was a non-significant trend (0% vs. 26.7% vs. 27.3%, P = 0.070). The laparoscopic surgery rate was 82%, the primary anastomosis rate was 92%, and bevacizumab was safely administered in all 6 patients who received it. Overall survival was significantly longer in the Quasi-BTS group than in either palliative group (log-rank all P < 0.001). After multivariable Cox adjustment for age, ASA, metastatic site, and targeted-therapy use, the Quasi-BTS group retained a markedly reduced hazard of death (adjusted HR 0.037, 95% CI 0.010-0.135). The mean interval from stent insertion to resection was 21.2 days in the resection-first subgroup.

conclusionsThe Quasi-BTS strategy may extend the bridge-to-surgery concept to metastatic colorectal cancer by repurposing stenting as a bridge for patient selection. Performing primary tumor resection within approximately three months of stent insertion was associated with the absence of stent-related complications in our cohort, appears to permit the subsequent use of anti-angiogenic targeted therapy without observed stent-related complications, and was associated with improved long-term survival.