Treatment Strategies and Outcomes for Single-Site Recurrent Pancreatic Ductal Adenocarcinoma After Curative-Intent Surgery: Local Therapies are Associated with Longer Survival in Selected Cases: A Systematic Review and Meta-analysis

BACKGROUND: After curative-intent pancreatectomy for pancreatic ductal adenocarcinoma (PDAC), disease recurrence occurs almost invariably. Evidence guiding treatment of recurrence remains limited and may differ across single-site recurrence patterns. METHODS: Scopus, MEDLINE, and the Cochrane Library were systematically searched for observational studies of adults with recurrent PDAC reporting liver-only, lung-only, or locoregional recurrence and post-recurrence treatments. Hazard ratio (HR) meta-analyses were performed to compare survival outcomes between treatment strategies for each recurrence location with additional descriptive survival summaries. RESULTS: The inclusion criteria were met by 22 studies, with 17 included in the quantitative synthesis. Pattern-specific analyses favored selected local therapies. For liver-only recurrence, local therapy was associated with longer overall survival than chemotherapy alone (HR 0.26, 95% confidence interval [CI] 0.14-0.49), mainly due to surgical resection (HR 0.18; 95% CI 0.11-0.31). Ablation did not reach statistical significance. In lung-only recurrence, surgical resection was associated with longer survival than conventional management (HR 0.35; 95% CI 0.26-0.48). For locoregional recurrence, resection was associated with longer survival (HR 0.52; 95% CI 0.38-0.72). Stereotactic body radiotherapy outcomes from three small series were summarized descriptively. CONCLUSIONS: Pancreatic ductal adenocarcinoma recurrence outcomes differ significantly by recurrence pattern. Across liver-only, lung-only, and locoregional recurrence, selected patients undergoing local therapy had longer survival than those managed conventionally. Although current observational data do not confirm broad efficacy for specific methods, these results support recurrence pattern-specific prospective evaluation to define optimal site-tailored strategies.