A Case of Follicular Pancreatitis Performed Distal Pancreatectomy

Abstract

A 68-year-old man was referred to our hospital with a high urinary albumin level detected at his neighbor hospital. Abdominal ultrasonography revealed an irregular-shaped hypoechoic mass in the tail of the pancreas. By abdominal contrast-enhanced CT scan and abdominal contrast-enhanced MRI, a 30-mm pancreatic neuroendocrine tumor in the pancreas tail was diagnosed to be probable which needed to be differentiated from pancreatic cancer or malignant lymphoma. Since there were no distant metastases, he underwent open distal pancreatectomy. Histopathological diagnosis was follicular pancreatitis. Follicular pancreatitis was first reported by Zen in 2012, and is a very rare disease presenting as a nodular tumor composed of hyperplasia of lymphoid follicles and fibrosis. It is often difficult to differentiate it from pancreatic malignant neoplasms. Surgery can be avoided if it is possible to be diagnosed preoperatively, but its characteristics have not been clarified due to its rarity. Therefore we present this case because of further case accumulation.