GM-CSF raises serum levels of beta(2)-microglobulin and thymidine kinase in patients with chronic lymphocytic leukaemia

The effects of granulocyte-macrophage colony-stimulating factor (GM-CSF) on biochemical tumour markers beta(2)-microglobulin (beta(2)m), thymidine kinase (TK) and lactate dehydrogenase (LDH) were studied in eight patients with chronic lymphocytic leukaemia (CLL). The serum concentration of beta(2)m rose by a median of 30% (range 8-50%) and serum TK by 101% (range 30-1414%), Serum LDH concentration, on the other hand, significantly decreased in all patients. The significant increases of beta(2)m and TK could not be explained by progression of the disease or impaired renal function, Treatment with GM-CSF reduces the value of serum beta(2)m and TK in assessment of tumour mass and disease activity.