Evaluation of lymphangiogenic markers in Sézary syndrome

Sézary syndrome (SS) is regarded as a leukemic, aggressive subtype of cutaneous T-cell lymphoma (CTCL) characterized by the accumulation of malignant T-cells in the skin, as well as by blood and lymph node involvement. To date there have been no data on the extent of lymphangiogenesis in SS or erythrodermic mycosis fungoides (eMF). Lymphangiogenesis represents the de novo formation of lymphatic vasculature and has been associated with the occurrence of metastatic disease and poor prognosis. In this study we investigated lymphangiogenesis in skin biopsies from patients with SS and eMF. The expression of VEGFR-3 was significantly higher in patients with SS (p = 0.0285) as compared to patients with eMF. LYVE-1, podoplanin (PDPN), and VEGF-C stainings showed a similar tendency. The number of PDPN-expressing lymphatic vessels (p = 0.025) as well as CD31-positive blood vessels (p = 0.0065) correlated with disease progression in patients with SS. We show for the first time a non-vascular pattern of VEGF-C and VEGFR-3, i.e. their epidermal expression in erythrodermic CTCLs, suggesting their role in lymphocyte trafficking to the skin.