PDPN and ulcer disease: To clarify the histological features of lymphatic vessels in patients with WS, we compared immunohistochemical staining using the podoplanin antibody in the skin of the non-ulcerated area (non-ulcer WS group) and the skin around the ulcer (ulcer WS group) of four patients with WS and the skin around the foot ulcer (ulcer PAD group) of three patients with peripheral arterial disease (PAD).