Recent studies indicate that angiogenesis may be involved in the pathogenesis of certain hematological malignancies. However as far as B-cell chronic lymphocytic leukemia (CLL) is concerned, current data dealing with the evaluation of bone marrow (BM) microvessel density, a marker of angiogenesis grade, do not as yet provide definitive results. It is now clear that the mRNA isoforms VEGF121 and VEGF 165 are expressed by B-CLL cells. In addition, low cellular and high serum levels of VEGF correlated with a poor clinical outcome. Although these data do not as yet show that angiogenesis is essential for B-CLL, it may indeed be relevant in the leukemic process so characteristic of this diseases.