A Comparative Evaluation of Fibrosis in Patients With and Without Chronic Pancreatitis Undergoing Pancreatic Surgery

Fibrosis is considered the gold standard for diagnosing chronic pancreatitis (CP) but has not been systematically studied across a large cohort of patients with and without pancreatitis undergoing different pancreatic surgeries.

Demographic, clinical, and radiologic data for patients undergoing total pancreatectomy with islet autotransplantation for indeterminate CP, recurrent acute pancreatitis (RAP), and definite CP; Whipple/Frey for indeterminate and definite CP; and distal pancreatectomy for serous cystadenoma between 2004 and 2023 were reviewed. Definite and indeterminate CP were defined by M-ANNHEIM criteria; and RAP defined as ≥2 episodes of imaging-documented acute pancreatitis. The Ammann Fibrosis Score (FS) was tabulated for all surgical pathology specimens. Patients with serous cystadenoma were included as controls. Data were summarized as median (interquartile range [IQR]) or number (%).

There were 206 patients including 24 controls, 31 with indeterminate CP, 36 with RAP, and 115 with definite CP. The median FS was 0.33 (IQR, 0.2-0.5), 2.8 (IQR, 1-6), 6.5 (IQR, 3.7-8), and 8.5 (IQR, 5.9-11) in controls, indeterminate CP, RAP, and definite CP, respectively. Post hoc Dunn tests with Holm adjustment showed significant differences in total FS across all diagnostic groups, with most component scores also differing significantly between groups. There was no correlation between FS and number of AP episodes; however, patients with genetic or idiopathic RAP with ≥7 episodes of AP had similar FS to genetic or idiopathic CP (P = .08).

Fibrosis quantification may provide complementary information to existing clinical, imaging, and functional assessments when evaluating patients across the pancreatitis continuum. Current diagnostic criteria for indeterminate CP are leading to an overdiagnosis of CP if fibrosis remains the criteria standard. Among genetic/idiopathic etiologies, patients with RAP with ≥7 episodes of AP have similar quantities of fibrosis to CP.