[A diagnostic challenge: paraduodenal pancreatitis. Two case reports]

The paraduodenal, or groove pancreatitis is a lesser-known type of chronic pancreatitis, often mimicking malignancy, hence resulting in serious differential diagnostic challenges. Herein we report two cases of this entity. Both required analysis of the surgical specimen in order to ensure the diagnosis due to inadequate preoperative histological sampling and a vague clinical presentation. In the first case, strong suspicion of malignancy following imaging, while in the second, severe gastric outlet stenosis indicated the resection. In our report, we give a clinicopathological summary from the literature of this entity, including its epidemiology, clinical presentation and applicable diagnostic methods as well as macroscopic and microscopic pathomorphology. The pathogenesis of this disease is complex. Beside the role of alcohol, anatomic variations of the pancreatic ductal system, pancreatic islets in duodenal wall resulting from incomplete involution of dorsal pancreas, or Brunner gland hyperplasia (often observed as part of the lesion) can all play a role in the disturbance of pancreatic fluid discharge in the minor papilla area, eventually leading to this specific localised inflammation. In addition, recent investigations revealed a susceptible role of genetic polymorphism in the persistent inflammatory disorders of the pancreas. Besides summarizing the differential diagnostic aspects, we also discuss therapeutic possibilities, underlining the conservative methods, which can be used with good efficacy after a successful identification of this entity. Orv Hetil. 2019; 160(22): 873-879.