Tumor-associated Pancreatitis Mimicking Autoimmune Pancreatitis in a Young Male: A Case of Main Duct IPMC.

We report a rare case of intraductal papillary mucinous carcinoma (IPMC) in a young male who initially presented with imaging findings suggestive of autoimmune pancreatitis (AIP) and was later diagnosed with tumor-associated pancreatitis. Despite symptom resolution with conservative treatment, follow-up imaging revealed a pancreatic tumor. Surgical resection confirmed the presence of IPMC with adenocarcinoma components. This case highlights the importance of excluding malignancy even in young patients with AIP-like features. Given the limited sensitivity of FDG-PET for early stage tumors, adjunctive modalities such as endoscopic ultrasound (EUS) and serial pancreatic juice aspiration cytological examination (SPACE) should be actively considered.