Long Term Outcomes and Recurrence Patterns Following Stenting as Bridge to Curative Surgery in Obstructing Colon Cancers: Note of Caution

Abstract

Objective: The aim of this study was to evaluate the long-term oncological outcomes and patterns of recurrence following endoscopic stenting as a bridge to surgery (SBTS) for non-metastatic obstructing colon cancers (OCCs).

Background: While self-expanding metallic stents (SEMS) have enjoyed relatively high technical and short-term clinical success rates in obstructing colon cancers, their usage as a bridge to surgery with curative intent remains debatable largely due to possibly worse oncological outcomes.Methods Retrospective cohort study of a prospectively collected database in a tertiary single center over 10 years from 2007 to 2016. Long-term outcomes including recurrence patterns and prognostic factors were analyzed.

Results: A total of 114 consecutive patients underwent SEMS placement for acute colonic obstruction. Of these, 27 patients had colonic obstruction due to anastomotic recurrences or non-colonic primary cause. Another 25 patients had stage IV obstructing colonic cancers at presentation. After excluding these cases, the final study population included 62 patients who underwent SBTS during the study period with a median follow-up duration of 39 months. The 3-year and 5-year overall survival rates were 74.3% and 58.8%, respectively. 28 patients (45.2%) developed metastases with median time to recurrence of 16 months (range 3-69 months). 18 patients had single-site metastases, and 10 patients had two or more sites of distant metastases. Among the 18 patients with single-site metastases, 4 had liver-only metastases, 4 had lung-only metastases, and 10 had peritoneum-only metastases. Overall, among these 28 patients with recurrences, the most common site of metastatic involvement was the peritoneum (n=17, 60.7%), followed by the liver (n=9, 32.1%), then lung (n=8, 28.6%). The median time to peritoneal recurrence was 14 months (range, 3-69 months), and for non-peritoneal recurrence was 17 months (range, 4-62 months) (p=0.990). Among the prognostic factors, lymphovascular invasion (LVI) was significantly associated with peritoneum-only recurrence. Peritoneum-only recurrence was associated with worse cancer-specific survival (CSS) on multivariate analysis.

Conclusion: SBTS is an emergency option for OCCs with reasonable overall long-term survival rates. However, the clear predominance and early peritoneal metastatic involvement among patients who develop recurrence is a cause for concern. LVI is associated with peritoneum-only recurrence.

Funding Statement: None.

Declaration of Interests: None.

Ethics Approval Statement: The study was approved by the institution review board.

Keywords: Self-expanding metallic stent; colorectal cancer; bridge to surgery; oncological outcomes; obstructing colorectal cancers; recurrence patterns