Lactate dehydrogenase activity in the diagnosis of malignant effusions

Enzyme assays in a series of 38 cases of pleural effusion and in 10 cases of ascites associated with malignant lesions and of 24 of pleural effusion and of five of ascites of benign origin do not support the suggestion that the estimation of the fluid lactate dehydrogenase serum ratios in pleural and peritoneal effusions is of value in the diagnosis of malignancy.