The increase in podoplanin-positive lymphatic vessels during the clinical progression of CTCL strongly correlates with the expression levels of vascular endothelial growth factor C (VEGF-C) which is a key stimulator of lymphangiogenesis (Stacker et al., 2014; Jankowska-Konsur et al., 2017). Here, PDPN is linked to primary cutaneous T-cell non-Hodgkin lymphoma.