Stenting with high-intensity focused ultrasound ablation for distal biliary obstruction caused by pancreatic carcinoma: a meta-analysis

Introduction
Between 42% and 77% of patients with distal malignant biliary obstruction (MBO) suffer from pancreatic carcinoma (PC).

Aim
To analyse the clinical efficacy of stenting accompanied by high-intensity focused ultrasound (HIFU) ablation in patients with distal MBO from PC.

Material and methods
Relevant articles published through March 2021 were identified in the Pubmed, Cochrane Library, Embase, Wanfang, VIP, and CNKI databases. RevMan v5.3 and Stata v12.0 were used for the meta-analysis.

Results
Twenty-nine articles were initially identified, and 5 of these were eventually included. These articles described 142 patients who underwent biliary stenting alone and 132 patients who underwent biliary stenting with HIFU ablation. The pooled  total bilirubin (TBIL) values were comparable between the 2 treatment groups (p = 0.10). The pooled stent dysfunction rate was significantly greater in the group with stenting alone (p = 0.03), and the pooled HR for the stent patency duration indicated that the duration of stent patency was increased in the stenting with HIFU ablation group (p < 0.0001). Overall survival rates were significantly longer in the stenting with HIFU ablation group (p < 0.0001). HIFU ablation was associated with an 80% pooled clinical response rate. The pooled cholangitis (p = 0.47) and pancreatitis (p = 0.56) rates were comparable between the 2 groups. Funnel plots did not reveal any significant evidence of endpoint-associated publication bias.

Conclusions
Stenting with HIFU ablation increased both stent patency and overall survival in patients with distal MBO caused by PC compared to stenting alone.