Expression level, tissue distribution pattern, and prognostic impact of vascular endothelial growth factors VEGF and VEGF-C and their receptors Flt-1, KDR, and Flt-4 in different subtypes of non-Hodgkin lymphomas

The aim of the study was to investigate the expression of angio-and lymphangiogenic molecules (vascular endothelial growth factors VEGF and VEGF-C and their receptors Flt-1, KDR, and Flt-4) in non-Hodgkin lymphomas (NHL) treated in the pre-rituximab era. Pre-therapeutic lymph-node biopsies from 155 patients with NHL (64 follicular lymphomas (FLs), 47 de novo diffuse large B-cell lymphomas (DLBCL) and 44 peripheral T-cell lymphomas (PTCL)) were stained by in situ hybridization and immunohistochemistry. Tumor cell expression of VEGF, VEGF-C and their receptors was detected in most of the analyzed biopsies. In FL, diffuse intratumoral VEGF staining correlated with shorter overall survival (OS) (p = 0.008) and diffuse KDR staining was associated with a higher risk of histologic transformation (p = 0.05). In DLBCL, high KDR expression predicted poor treatment response (p = 0.03) and had a significant adverse impact on OS (p < 0.001). In PTCL, diffuse tissue distribution of VEGF mRNA correlated with an unfavorable 5-year OS (p = 0.004).