Risk of Pancreatic Cancer After Acute Pancreatitis: A Retrospective Analysis of the Korean National Sample Cohort

Abstract

Background: Acute pancreatitis may increase the risk of pancreatic cancer, although this association remains unclear. Therefore, we aimed to investigate this association. Methods: We retrospectively analyzed the 2002–2019 Korean National Health Insurance Service-National Sample Cohort using 1:3 propensity score matching for sex and age (acute pancreatitis, n = 4,494; matched controls, n = 13,482). We calculated the hazard ratio (HR) for pancreatic cancer risk in patients with acute pancreatitis using Cox proportional hazards regression. Results: Acute pancreatitis was significantly associated with an increased risk of pancreatic cancer throughout the study period (adjusted HR, 7.56 [95% confidence interval, 5.00–11.41]), which persisted for 2, 2–5, and > 5 years post-diagnosis (19.11 [9.60–38.05], 3.46 [1.35–8.33], and 2.73 [1.21–6.15], respectively). This pancreatitis-related pancreatic cancer risk became insignificant beyond 10 years of follow-up (1.24 [0.24–6.49]). Furthermore, this risk notably increased as the number of recurrent acute pancreatitis episodes increased (1 episode: 5.25 [3.31–8.33], 2 episodes: 11.35 [6.38–20.19], ≥ 3 episodes: 24.58 [13.66–44.26]). Conclusion: Following an acute pancreatitis diagnosis, the risk of pancreatic cancer increases significantly in the initial years, with a rapid increase further accentuated with recurrent acute pancreatitis episodes. Additional study is needed to evaluate whether this increased risk of carcinogenesis is attributed to accumulated inflammation.