We describe a case of exudative pleural effusion in a patient with mucinous pulmonary adenocarcinoma. Pleural fluid examination showed markedly raised amylase with normal serum amylase concentration. There was no clinical or radiological evidence of oesophageal rupture or pancreatitis. The case illustrates the importance of considering pulmonary malignancy in the context of amylase-rich pleural effusion. Causes of amylase-rich pleural effusion and the significance of isoenzyme analysis are discussed.
