Sukit Pattarajierapan1, Panat Tipsuwannakul1, Sasiprang Kongboonvijit2, Supakij Khomvilai1

1Surgical Endoscopy Colorectal Division, Department of Surgery, Faculty of Medicine, Chulalongkorn University, Phayathai Road, Pathumwan, Bangkok, 10330, Thailand, 2Department of Radiology, Faculty of Medicine, Chulalongkorn University, Phayathai Road, Pathumwan, Bangkok, 10330, Thailand

Background/Aims: Self-expandable metal stent (SEMS) is an alternative treatment to surgery for patients with incurable malignant colonic obstruction. Palliative SEMS insertion significantly improves the quality of life, mainly from stoma avoidance. However, perforation is the most feared potential complication because of its serious consequences. Nowadays, the characteristics of the lesions and patients that may lead to perforation remain unclear. The ability to predict SEMS-related perforation may lead to better patient selection and outcome improvement. This study aimed to identify risk factors that may predict perforation after SEMS insertion in palliative malignant obstruction.

Methods: Between January 2009 to December 2019, this retrospective cohort included patients with malignant colonic obstruction who underwent SEMS insertion with palliative intent. Patients who had peritonitis, SEMS insertion as a bridge-to-surgery, technical failure, or surgical intervention were excluded.

Results: There were 111 patients who underwent palliative SEMS insertion in this period. The technical success and clinical success rates were 98% and 97%, respectively. The SEMS-related perforation rate was 8%. The median time to perforation was 22 days (range 1-480). Multivariate analysis showed peritoneal metastasis to be a significant risk factor of SEMS-related perforation (hazard ratio [HR], 5.336;95% confidence interval [CI], 1.219-23.367; p = 0.026), while tumor length ≥ 5 cm, tumor at angulated segment, chemotherapy, and bevacizumab administration were not (p = 0.245, p = 0.168, p = 0.122, and p = 0.824, respectively) (Table 1).

Conclusion: Peritoneal carcinomatosis is the only significant risk factor of SEMS-related perforation in this study.

Keywords: Perforation, Colonic stenting, Malignant colonic obstruction, Palliation, Colon cancer