CT presentations of pancreatic lymphoma: what radiologists need to know

Pancreatic lymphoma is a rare entity that can mimic other pancreatic pathologies, particularly pancreatic ductal adenocarcinoma (PDAC), making accurate radiologic recognition essential as management differs significantly. Pancreatic lymphoma is treated with chemotherapy and generally carries a more favorable prognosis, whereas PDAC typically requires surgical intervention. Through a series of illustrative cases, many of which were initially referred to a PDAC multidisciplinary conference but ultimately proven to be lymphoma, we highlight the diverse CT imaging spectrum of pancreatic lymphoma, which extends well beyond the classically described bulky pancreatic mass. Observed patterns include focal well-defined hypodense masses, multifocal pancreatic lesions, diffuse infiltrative enlargement mimicking pancreatitis, and masses with extrapancreatic spread into adjacent organs. While classic features such as absent pancreatic ductal dilatation, lack of vascular occlusion, and homogeneous hypoattenuation can help distinguish lymphoma from PDAC, variant presentations with ductal dilation, necrosis, or vascular involvement may occur. Awareness of these diverse imaging appearances may help radiologists include pancreatic lymphoma in the differential diagnosis of hypodense pancreatic masses, advising tissue sampling to ensure accurate diagnosis and guide appropriate management.