PTPRC and melanoma: Other pertinent negative immunostains include hematolymphoid markers (CD45, CD3, CD20, CD79a), myoid markers (smooth muscle actin (SMA), desmin), vascular markers (CD31, CD34), epithelial markers (EMA, keratins), melanoma markers (melanA, SOX10, HMB45, S100), and other markers (ALK, CD30) [44,45].