The purpose of this study was to evaluate the clinicopathologic characteristics, diagnosis and treatment of mucinous cystadenocarcinomas (MCACs) of the pancreas.This is a retrospective review of 6 patients who underwent curative resection for MCACs of the pancreas in the Department of General Endocrine and Transplantation Surgery, Medical University of Gdańsk from 1994-2004. Clinical presentation, radiological evaluation and surgical procedures were analyzed.There were 4 women and 2 men. Median age was 59 years. Patients complained of abdominal pain, nausea, vomiting and weigh loss, 2 of them had jaundice and 1 gastrointestinal (GI) bleeding. Ultrasonography and computed tomography showed cystic lesions. Solid component was found in 3 cases. Three endoscopic retrograde cholangiopancreatographys (ERCPs) were unhelpful in differentiating between malignant tumor and benign lesion. All patients underwent resection. In 3 cases Whipple resection, in 1 case Traverso - Longmire resection and in 2 cases distal pancreatectomy was performed. Histopathologically, all tumors were mucinous cystadenocarcinomas.Diagnostic accuracy for cystic pancreatic neoplasm is still limited. Surgical resection is recommended in all cystic tumors that are not clearly defined.