Acinar cystic transformation of the pancreas

Background: Acinar cystic transformation (ACT) of the pancreas is a non-neoplastic cystic lesion lined by acinar and ductal epithelium. Only 84 cases including this report have been described in the literature. Case report: The clinical history, imaging, macroscopic, histologic and immunohistochemical features were consistent with acinar cystic transformation of the pancreas in a 24-year-old female. Discussion: Although rare, ACT of the pancreas should be considered as a differential diagnosis when considering cystic lesions of the pancreas. Cytological examination of aspirated fluid is often inconclusive or may not correlate with the final histological diagnosis. Micro biopsies via EUS examined histologically with immunohistochemical support may help distinguish ACT from relevant premalignant differentials including an intraductal papillary mucinous neoplasm and mucinous cystic neoplasm. References 1. WHO Classification of Tumours Editorial Board. Digestive system tumours. Lyon (France): International Agency for Research on Cancer 2019. WHO classification of tumours series, 5th ed, Vol 1). 2. Rift CV, Hasselby JP, Hansen CP, Federspiel B. Acinar cystic transformation of the pancreas: report of a case and a review of the literature. Pathol Res Pract 2020; 216: 152928. 3. Lee JH, Jung SJ, Park YH, Park SJ, Choi JS. Pancreatic Acinar Cell Cystadenoma Mimicking Pancreatic Serous Cystadenoma. Korean J Gastroenterol 2021; 78: 138–143.