Outcomes of two types of iodine-125 seed delivery with metal stents in treating malignant biliary obstruction: a systematic review and meta-analysis

PURPOSE: To conduct a meta-analysis comparing the efficacy and safety of two types of iodine-125 (I-125) seed delivery with metal stents (the study group) versus conventional metal stents (the control group) in patients with malignant biliary obstruction (MBO). METHODS: Our team systematically searched the PubMed, Embase, and Cochrane Library databases for relevant studies published from January 2012 up to July 2021. Survival time and stent dysfunction were the primary measured outcomes. Subgroup analyses were conducted according to the type of I-125 seed delivery. RESULTS: Eleven studies, including 1057 patients in total, were pooled for stent dysfunction. The study group showed a lower risk of stent dysfunction than the control group [odds ratio (OR): 0.61, 95% confidence interval (CI) 0.46–0.81, P = 0.001]. The pooled results of six studies reporting overall survival (OS) showed that the study group had a better survival outcome than the control group [hazard ratio (HR): 0.34, 95% CI: 0.28–0.42, P < 0.001]. In the subgroup analyses, the I-125 seed stent group had significantly less stent dysfunction than the control group (OR: 0.49, 95% CI: 0.31–0.76, P = 0.002). Meanwhile, the metal stents + I-125 radioactive seed strand group showed significantly more improvement in OS than the control group (HR: 0.33, 95% CI: 0.26–0.42, P < 0.001). Moreover, our analysis suggests that using I-125 seeds did not result in increasing related adverse events compared with using metal stents alone (all P > 0.05). The study group was significantly superior to the control group, with better survival and decreased stent dysfunction. Meanwhile, the delivery of I-125 seeds did not increase adverse events. CONCLUSION: The delivery of I-125 with metal stents may be considered a preferable technique for MBO.