Severity of initial stent angulation predicts reintervention after successful palliative enteral stenting for malignant luminal obstruction

Background and Aim: Recurrent stent obstruction necessitating reintervention is problematic and incompletely understood. The aim of the present study was to identify factor(s) predisposing to reintervention. Methods: Retrospective review of patients (n=117) referred to a single major endoscopic referral centre for palliative enteral stenting from 1999 to 2006. Twelve were excluded due to inadequate follow-up data (n=7) or initial radiographic documentation (n=5). A total of 105 patients (gastroduodenal n=57, colonic n=48) were therefore analyzed. The primary outcome of interest was recurrent obstruction necessitating reintervention. Kaplan-Meier analysis of potential factors predisposing to reintervention, including stent angulation (mild [<15°], moderate [15°-90°], severe [>90°]) was completed for 98 patients (technically successful enteral stenting). Results: Technical and clinical success were achieved in 98 of 105 (93.3%) and 92 of 98 (93.9%) cases, respectively. Post-stenting median survival was 97.5days (range 3-1054). Eighteen patients (18.4%) required reintervention for stent obstruction at a median time to reintervention of 85days (range 7-481). Increased stent angulation (severe vs mild hazard ratio 6.73 (95% confidence interval 1.59-27.59), P=0.009) was the only statistically significant factor in multivariate analysis predicting reintervention. Conclusions: Despite its limitation as a retrospective review, this study found that reintervention for stent obstruction is necessary in almost one in five cases, and increasing severity of stent angulation is the most important risk factor.