Pancreatic Follicular Lymphoma Presenting as Acute Pancreatitis: Report of a Case

Pancreatic B-cell lymphoma is rare; it accounts for 0.2% to 2.0% of extranodal non-Hodgkin lymphoma, and constitutes less than 0.5% of all pancreatic malignancies. Most histologic types of the pancreatic lymphoma are diffuse large B-cell lymphoma, and follicular lymphoma is quite rare. We report here a case of pancreatic follicular lymphoma that was initially detected by acute pancreatitis. This is the first reported case of pancreatic follicular lymphoma presenting with acute pancreatitis. A 71-year-old woman had epigastric and left upper quadrant abdominal pain. Computed tomography (CT) revealed features of acute pancreatitis. After standard therapy for pancreatitis, enhanced CT showed a pancreatic tumor (50 × 35 mm) in the body of the pancreas with gradual enhancement. Endoscopic retrograde cholangiopancreatography and magnetic resonance cholangiopancreatography showed a complete interruption of the pancreatic duct in the body, with mild dilation of the duct in the tail of the pancreas. Endoscopic ultrasonography revealed hypervascularity of the pancreatic tumor. The patient underwent distal pancreatectomy to remove the cause of pancreatitis and to disclose the diagnosis. Histologic examination revealed follicular lymphoma of pancreas. Despite recent improvement in clinical strategies, differential diagnosis between pancreatic lymphoma and pancreatic cancer is still difficult without histologic information. Pancreatic lymphoma should be considered as a differential diagnosis in a patient who initially presents with acute pancreatitis.Key words: Pancreatic lymphoma, Acute pancreatitis, Follicular lymphomaPancreatic B-cell lymphoma is rare; it accounts for 0.2% to 2.0% of extranodal non-Hodgkin lymphoma¹ and constitutes less than 0.5% of all pancreatic malignancies.^2,3 Most histologic types of pancreatic lymphoma are diffuse large B-cell lymphoma, and follicular lymphoma is quite rare. In addition, acute pancreatitis caused by pancreatic lymphoma is also rare.Despite recent improvements in clinical strategies, differential diagnosis of pancreatic lymphoma with pancreatic cancer or autoimmune pancreatitis (AIP) is still difficult without histologic examination.We report here a rare case of a 71-year-old female with pancreatic follicular lymphoma that initially presented as acute pancreatitis.