VTCN1 and extramammary Paget disease: Given this evidence and the clinical need to expand therapeutic options for local and metastatic EMPD, the purpose of this study was to characterize EMPD tumor cell expression of select currently targetable B7 family members, B7-H3, B7-H4, PD-L1, programmed death-ligand 2 (PD-L2) and CTAs, NY-ESO-1 and MAGE-A.