Fluorescence polarization as a parameter of plasma lipids in patients with hematologic malignancies.

Abnormal diphenylhexatriene fluorescence polarization measurements (FP values) of plasma have previously been reported in patients with hematologic malignancies. However, the biological significance of this measurement is unclear. We have prospectively studied plasma from 39 patients with leukemia and lymphoma as well as normal donors for total cholesterol, total triglyceride, and lipoprotein-cholesterol fractions, and correlated these values with measured FP values. Total triglyceride, very low density lipoproteins (VLDL), high density lipoprotein (HDL) levels, and FP values were all strongly correlated with clinical and biochemical measures of tumor burden and varied directly with the presence of malignancy. Although the presence of abnormal FP values was confirmed in patients with leukemia and lymphoma, it was not a particularly sensitive measure for minimal tumor and it appeared to correlate directly with other measures of lipids and cholesterol, particularly triglyceride. It is suggested that further studies of conventional plasma lipids and lipoproteins be pursued in order to elucidate the apparently pervasive alterations in lipid metabolism present in these patients.