2025 Volume 40 Issue 1 Pages 58-66
A 69-year-old man was admitted to our hospital with a diagnosis of acute pancreatitis. Computed tomography (CT) revealed a hypodense mass in the pancreatic tail, and magnetic resonance imaging (MRI) showed high- and low-signal intensity on T1- and T2-weighted images, respectively. Endoscopic ultrasound-guided tissue acquisition (EUS-TA) and serial pancreatic-juice aspiration cytologic examination did not reveal any evidence of malignancy. The patient refused surgical treatment and underwent follow-up with imaging. MRI performed 2 months later revealed shrinkage of the pancreatic tail mass without any significant change in the imaging findings thereafter. Imaging performed 30 months later showed local enlargement of the mass; therefore, we repeated a third EUS-TA, and the patient was diagnosed with a pancreatic neuroendocrine tumor (NET). We performed laparoscopic distal pancreatectomy, which confirmed a final diagnosis of NET G1. The delayed diagnosis (30 months) was attributable to the atypical imaging findings and course of the NET, and the lack of conclusive histopathological diagnosis at the time of initial examination.
