Not every pancreatic mass is cancer: a case of a large intra-pancreatic splenule

We report a case of a 72-year-old man who was referred to our tertiary medical center for endoscopic ultrasound (EUS) evaluation for an incidental 2-cm mass in the tail of the pancreas seen on computed tomography (CT). On EUS, a 22 mm by 13 mm, well-defined hypoechoic mass was identified within the pancreatic tail, and a fine-needle biopsy was performed. Histopathology revealed benign pancreatic parenchyma and the presence of lymphocytes. A technetium-99m sulfur colloid scan was performed, which demonstrated uptake in the pancreatic tail lesion consistent with an intra-pancreatic splenule. This case demonstrates that a splenule or accessory splenic tissue should remain in the differential diagnosis of a pancreatic mass. An accurate diagnosis of pancreatic splenule can preclude surgical resection.