Although computed tomography and endoscopic ultrasound (EUS) are well-established procedures used to evaluate pancreatic masses, it is well known that imaging techniques alone cannot be used to distinguish between adenocarcinoma and tumors of less common cellular origin, such as primary pancreatic lymphoma. Clinicians must always consider this kind of malignancy in their differential diagnosis since, although rare, its treatment is nonsurgical and it has a better prognosis than adenocarcinoma. Histological examination of focal masses in the pancreas is therefore mandatory in order to establish the best therapeutic approach for every patient. Endoscopic ultrasound has developed as a very useful tool for the diagnosis of pancreatic tumors but could also be considered as a very useful method in the follow-up of these patients after treatment.