A mixed-type intraductal papillary mucinous neoplasm of the pancreas with a histologic combination of gastric and pancreatobiliary subtypes in a 70-year-old woman: a case report

BACKGROUND: Intraductal papillary mucinous neoplasms are rare papillary pancreatic neoplasms arising from major pancreatic ducts, characterized by duct dilation and mucin secretion. They comprise approximately 1% of all exocrine neoplasms and are classified according to their anatomical sites into main duct-type, branch duct-type, and mixed-type intraductal papillary mucinous neoplasms. Histological examination plays a crucial role in distinguishing and classifying intraductal papillary mucinous neoplasms into gastric, intestinal, pancreatobiliary, and oncocytic subtypes. CASE PRESENTATION: We present the case of a 70-year-old Syrian woman who was admitted to our hospital due to an intermittent epigastric pain accompanied by diarrhea and weight loss with a recent diagnosis of diabetes mellitus. Following clinical, laboratory, and radiological examination, distal pancreatectomy involving the body and the tail of the pancreas was performed. Interestingly, histological examination of the resected specimens revealed the diagnosis of a mixed-type intraductal papillary mucinous neoplasm with a unique combination of gastric and pancreatobiliary subtypes. CONCLUSION: To the best of our knowledge, the combination of multiple histological subtypes of intraductal papillary mucinous neoplasms has been recorded in a few studies with reference to the challenging histological detection. Herein, we report a rare case with a significant histological combination, highlighting the difficulties in differential diagnosis due to the absence of ancillary techniques, with a brief review on diagnostic methods, histological characteristics and surgical recommendations.