Primary cutaneous T-cell lymphomas (CTCL) represent a heterogeneous group of neoplasms derived from skin-homing T cells. CTCL behave similarly to indolent B-cell lymphomas. There is increasing evidence that angiogenesis may be important in lymphoproliferative disorders. The aim of the study was to evaluate microvessel density (MVD) as a parameter of tumor angiogenesis measured by the expression of CD34 in the skin samples in CTCL patients. Formaldehyde-fixed, paraffin-embedded skin tumor biopsy specimens from 25 patients (16 men, 9 women) with CTCL (mycosis fungoides), and 8 skin samples from healthy volunteers were analysed. The preparations were stained with haematoxylin and eosin, and evaluated histopathologically. Staining for endothelial cells with monoclonal antibody against CD34 revealed a mean number of 134 dots per mm2 for CTCL and 106 dots/mm2 for controls; the difference was statistically significant (p=0.0388). Our study shows a higher number of microvessels in primary CTCL compared with normal skin. Microvascular endothelial cells have become an important target in cancer therapy. Increased MVD in the skin of CTCL patients indicate that angiogenesis may play a role in the growth of CTCL, and raises the possibility of using angiogenesis inhibitors in CTCL therapy.