Angiogenesis appears to be an important player in biology of chronic lymphocytic leukemia (CLL). We present here data on association of ZAP-70 expression measured by flow cytometry and plasma levels of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) in 27 untreated CLL patients. We found significantly higher VEGF (but not bFGF) in ZAP-negative patients. Likewise, there was a negative correlation between percentage of ZAP-70 expression and VEGF. Larger, prospective studies are needed to confirm our pilot data.