Timing of minimally invasive step-up intervention for symptomatic pancreatic necrotic fluid collections: A systematic review and meta-analysis

•Optimal timing of intervention in symptomatic pancreatic fluid necrotic collections.•Treating symptomatic pancreatic fluid necrotic collections, early intervention did not increase mortality or complication rates in patients. Minimally invasive step-up interventions are now the standard treatment recommended by current guidelines for symptomatic pancreatic necrotic fluid collections (PNFC); however, it is controversial whether delayed treatment after four weeks should always be used in patients who have failed conservative treatment and whose condition has not improved or worsened. The aim of this meta-analysis was to evaluate the impacts of the different timing of interventions on the clinical outcomes and prognosis of patients with symptomatic PNEC requiring intervention. We searched Embase, Cochrane Library, PubMed and Web of Science databases to identify comparative studies assessing the safety and efficacy of early and postponed interventions in treating symptomatic PNFC. Primary outcome: Mortality. Secondary outcomes included some major complications, need for further minimally invasive necrosectomy and length of hospital stay. This meta-analysis included ten studies (2 RCTs and 8 observational studies) with a total of 1178 symptomatic PNFC patients who required intervention. Pooled results showed that there was no significant difference between early minimally invasive intervention and postponed intervention in mortality(OR 1.41, 95%CI 0.93–2.12;p = 0.10) and the incidence of early and late complications, but the early intervention group had a significantly increased need for further minimally invasive necrosectomy compared with postponed intervention (OR 2.04,95%CI 1.04–4.03; p = 0.04). There was no increase in length of stay for patients who received early intervention compared to postponed drainage (MD 3.53, 95% CI -4.20, 11.27; p = 0.37). Intervention before four weeks should be considered for patients with PNFC complicated by persistent organ failure or infections, who have been treated conservatively to the maximum extent possible.