PTPRC and melanoma: Taking a detailed past medical history helped us choose the precise immunomarkers and determine the origin of tumors.Depending on the microscopic features of the neoplasm, immunoreactivity against pan cytokeratins, p63, S100, vimentin or desmin, and LCA (CD45) typically comprise the preliminary screening panel to rule out metastatic carcinoma, melanoma, sarcoma, and lymphoma, respectively [ 2, 9].