Mucinous cystadenoma of the pancreas as a cause of acute pancreatitis

Acute pancreatitis is only rarely the first presentation of a cystic neopla sm of the pancreas. Mucinous cystadenomas have not been reported to be a ca use of acute pancreatitis; however, we present two cases of mucinous cystad enoma of the pancreas which have caused acute pancreatitis. Both patients ( female) presented acute abdominal pain, with serum amylase elevation and ul trasound scan (US) and computed tomography (CT) evidence of moderate pancre atitis, which resolved with medical treatment, fluid collection in the dist al pancreas had been misinterpreted as a pseudocyst. There was no history o f alcohol abuse or gallstone disease. After distal pancreatectomy the diagn osis of mucinous cystadenoma was confirmed; in one case a large pseudocyst was associated with this diagnosis. Pre-operative differential diagnosis between inflammatory and neoplastic cy sts is difficult, especially when the patient's first presentation is due t o an episode of acute pancreatitis. A neoplastic cyst should be considered when acute pancreatitis attacks occur in non-alcoholic women, who do not ha ve gallstone disease.