Abnormal blood lipid profiles have been reported in human malignancies. So, it is likely an overall involvement of tumoral cell metabolism. The aim of this study was to evaluate clinico-biological implications of altered lipid profiles in oncohaematologic patients.The plasma lipids, lipoproteins and apolipoproteins were determined at the time of diagnosis in 48 previously untreated patients (35M, 13F, median age 60 years), 11 with multiple myeloma (MM), 11 with non-Hodgkin's lymphoma (NHL), 11 with acute leukemia (AL), 10 with chronic myeloproliferative disorders (CMD) and 5 with B-chronic lymphocytic leukemia (B-CLL). The results were correlated with known prognostic serum markers, such as lactate dehydrogenase (LDH), beta-2-microglobulin (beta 2m), and soluble molecule ICAM1 (sICAM1).Altered blood lipid profiles were observed in all concohaematologic patients. Statistically significant values included reduced cholesterol (155 +/- 47.36 vs 205 +/- 35 mg/dl; p < 0.001), HDL-C (30.47 +/- 13.36 vs 45 +/- 10 mg/dl; p < 0.003) and apo A (118.86 +/- 49.98 vs 182.69 mg/dl; p < 0.0001) levels. No correlations were found between cholesterol levels and clinico-biological features representative of tumor mass (LDH, beta 2m, sICAM-1). A significant increase of cholesterol levels was observed in all patients responding to therapy.These results support the idea that the cholesterol, its fractions and the apolipoproteins determinations might be considered as useful biochemical and prognostic markers in hematologic neoplasms.