Pathology Analysis Reveals That Dysplastic Pancreatic Ductal Lesions Are Frequent in Patients With Hereditary Pancreatitis

Background & Aims: Hereditary pancreatitis (HP) is a risk factor for pancreatic adenocarcinoma. We performed a retrospective, multicenter study to characterize and evaluate the frequency of pancreatic intraepithelial neoplasia (PanIN) and to describe the characteristics of fibrosis in pancreatic surgical specimens from patients with HP. Methods: Samples from partial pancreatectomies (n = 13) of patients with HP complications (n = 12; 7 males; mean age, 24 y; 1 patient underwent 2 surgeries over 16 years) were analyzed by histologic and immunohistologic analyses; patients with suspected or proven pancreatic adenocarcinoma were excluded. HP diagnosis was confirmed by analysis of PRSS1 mutations. Dysplastic lesions were described according to the PanIN classification. Results: Eleven patients were found to have the R122H mutation in PRSS1 and 1 patient was found to have the N29I mutation in PRSS1. Fifty-one PanIN lesions were observed in 10 specimens (77%): PanIN lesions 1a, 1b, 2, and 3 were observed in 8, 5, 8, and 5 specimens, respectively. The median number of PanIN lesions was 3.5 for each specimen. The density of the lesions was 2.6 per 10 cm². The size of lesions was greater than 0.5 mm in 55% of the samples. Two patients with PanIN-3 developed pancreatic cancer, 18 months and 44 years after surgery. Conclusions: PanIN lesions are frequent, severe, and occur early in the course of HP. Among patients with PanINs, 50% had PanIN-3 lesions. Pancreatectomy could be considered as a prophylactic against pancreatic cancer in patients with high-grade dysplasia.