Association of Pancreatic Cancer with Acute Pancreatitis: A Systematic Review and Meta-Analysis.

[INTRODUCTION] The magnitude and modifiers of the association between acute pancreatitis (AP) and pancreatic cancer (PC) are unclear. This systematic review and meta-analysis aimed to quantify the occurrence of PC in AP, the association of PC after AP, and the impact of specific risk factors on PC diagnosis.

[METHODS] The systematic search was conducted in PubMed, EMBASE, and Central Register of Controlled Trial from inception until July 14, 2025 (PROSPERO: CRD42023470350). Eligible studies included adult populations reporting on the association between AP and PC. Primary outcomes included prevalence, incidence, and diagnosis of PC in individuals with AP, including subset analyses of specific clinical and demographic factors. Meta-analyses were performed using random-effects models to calculate pooled outcome measures and corresponding 95% confidence intervals (CI).

[RESULTS] A total of 61 studies were included. The prevalence of PC among AP patients was 2% (CI: 2%-4%). The time-dependent analysis revealed an increased hazard of PC in AP vs no AP: <24 months (HR: 31.94, CI: 9.35-109.09), 24-60 months (HR: 2.68, CI: 1.65-4.37), and >60 months (HR: 1.71, CI: 1.22-2.40). AP patients with subsequently diagnosed chronic pancreatitis (OR: 3.71, CI: 2.00-6.90), new-onset diabetes mellitus (OR: 2.22, CI: 1.02-4.84), idiopathic AP (OR: 2.97, CI: 1.44-6.13), and older than 50 years (OR: 4.04, CI: 2.73-5.97) showed significantly increased odds of having PC. We found no evidence for increased odds for PC with AP severity, smoking, and alcoholic and gallstone etiologies.

[DISCUSSION] Patients with AP have a higher likelihood of PC diagnosis, especially within the first 2 years. Although the association decreases with time, it remains significant long term. Newly diagnosed chronic pancreatitis, new-onset diabetes mellitus, idiopathic AP may further elevate the likelihood of PC diagnosis. PC diagnosed after AP tends to occur at a younger age, more often at an earlier stage, typically in the pancreatic head.