Angiogenesis in cutaneous lymphoproliferative disorders - Microvessel density discriminates between cutaneous B-cell lymphomas and B-cell pseudolymphomas

The role of angiogenesis in neoplastic disorders is supported by the eviden ce that tumor growth beyond a certain size requires induction of new blood vessels. The extent of tumor-associated angiogenesis, measured as microvess el density (MVD), has shown to correlate with aggressiveness and the progno stic outcome in several malignant neoplasms. Few data have been reported on the angiogenic response in lymphoproliferative diseases. In this study, th e MVD has been assessed in benign and malignant primary cutaneous B-cell ly mphoproliferative disorders. MVD was determined in formaldehyde-fixed, para ffin-embedded specimens of primary cutaneous B-cell lymphomas (CBCL n = 18) and cutaneous B-cell pseudolymphomas (B-PSL; n = 22) according to previous ly described protocols but was performed using computer-aided microscopic m orphometry. The endothelial cells of microvessels were identified by immuno histochemical staining for factor VIII-related antigen and CD31. The MVD wa s 99 dots/mm(2) for CBCL and 68 dots/mm(2) for PSL, and a MVD of 115 dots/m m(2) for CBCL and 73 dots/mm(2) for PSL by using an antibody against factor VIII-related antigen and CD31 antigen, respectively. Univariate analysis r evealed statistically highly significant differences in MVD between CBCL an d B-PSL (P = 0.0036 with staining for factor Vm-related antigen and P = 0.0 002 with staining for CD31 antigen). This study analyzes for the first time the angiogenic response in CBCL compared with that of B-PSL and demonstrat es that MVD discriminates between CBCL and B-PSL. However, because of an ov erlap in the ranges of MVD in CBCL and PSL, the MVD is not useful as a diag nostic tool in individual cases.