Autoimmune pancreatitis. Report of 10 cases Background: Autoimmune pancreatitis is a special form of chronic pancreatitis, more common in men and usually presenting as obstructive jaundice or abdominal pain. It may be associated with other immunological disorders and sometimes it is possible to find positive serological markers. Typical images show pancreatic enlargement with focal or diffuse stenosis of the pancreatic duct but sometimes it presents as a focal pancreatic mass, that is difficult to differentiate from pancreatic carcinoma. Aim: To report ten cases of autoimmune pancreatitis. Material and Methods: Retrospective review of clinical records of 10 patients aged 26 to 56 years (six males) with autoimmune pancreatitis. Results: The clinical presentation was obstructive jaundice in six cases, acute pancreatitis in two, persistent increase in serum amylase and lipase in one, and permanent abdominal pain and weight loss in one. On imaging studies, a circumscribed mass was found in six patients. An endoscopic retrograde colangiopancreatography was performed in four patients showing an abnormal pancreatic duct in all. Six patients were operated and tissue for pathological study was obtained in five, showing inflammatory infiltration. Five patients were treated with steroids with a good clinical response. Conclusions: Autoimmune pancreatitis must be borne in mind in the differential diagnosis of pancreatic lesions.