Purpose: This study aimed to compare the survival benefits between high-intensity focused ultrasound (HIFU) combined with chemotherapy and chemotherapy alone in patients with unresectable pancreatic ductal adenocarcinoma (PDAC).
Methods: All randomized clinical trials (RCTs) and observational studies were systematically searched through the databases of PubMed, EMBASE, CNKi and CQVIP up to December 2020. Case reports, case series and nonsystematic reviews were excluded. A meta-analysis was conducted to generate combined hazard ratios (HRs) with 95% confidence intervals (CI) for overall survival (OS).
Results: Seven trials, containing a total of 992 patients, were included in this study. The meta-analysis showed that a combination of HIFU and chemotherapy increased overall survival compared with chemotherapy alone, with a pooled HR of 0.40 (95% confidence interval [CI], 0.28-0.58). The combined therapy group had a significant advantage in 1-year survival rate (OR: 0.35, 95% CI: 0.22-0.53, p = 0.00). The trial sequence analysis (TSA) showed that there were enough trials to control for random errors.
Conclusion: Our analysis suggests that HIFU combined with chemotherapy intravenously will prolong survival for unresectable PDAC patients. The TSA showed that the survival benefit of combined therapy was definitive and there was no need to expand the sample size for repetitive exploration.
Keywords: HIFU; PDAC; TSA; chemotherapy; overall survival.