Colonic stenting in acute malignant large bowel obstruction - an audit of efficacy and safety in a tertiary referral centre in Singapore

Introduction: Acute malignant large bowel obstruction (MBO) occurs in 8-15% of colorectal cancer patients. Self-expandable metal stents (SEMS) have progressed from a palliative modality to use as bridge-to-surgery (BTS). We aimed to conduct a clinical audit on safety and efficacy of SEMS for MBO in our institution. Methods: Data from a prospectively maintained electronic database in a tertiary referral centre in Singapore was reviewed for all consecutive patients undergoing SEMS insertion for MBO. Technical success defined as successful SEMS deployment across tumour without complications. Clinical success defined as colonic decompression without requiring further surgical intervention. Rates of complications, median time to surgery, types of surgery and rates of recurrence were studied. Results: 79 patients underwent emergent SEMS placement from September 2013 to February 2020. Mean age 68.8±13.8 years, male 43/79 (54%). Mean tumour length 4.2cm±2.2cm; 89.9% (71/79) distal to splenic flexure. Technical and clinical success was 94.9% (75/79) and 98.7% (74/75), respectively. Perforation occurred in 5.1% (4/79), with no cases of stent migration or bleeding. 50/79(63.3%) of SEMS inserted as BTS. Median time to surgery was 20 days (range 6-57). Majority (41/50;82%) underwent minimally invasive surgery (robotic-assisted 7/50,14%; laparoscopic 34/50,68%). Primary anastomosis rate was 98% (49/50). 39 patients had follow-up beyond 1-year post-treatment (median 34 months). Local recurrence and distant metastasis were observed in 4/39(10.3%) and 5/39(12.8%), respectively. Conclusion: SEMS acute MBO has high technical and clinical success rates with a good safety profile. Majority of patients in our audit underwent minimally invasive surgery and primary anastomosis after successful BTS.