CDK4 and well-differentiated liposarcoma: Currently, MDM2 and CDK4 using FISH immunochemical staining are considered as criterion standard methods for IHC.[23–25] However, errors in interpretation of ICH have been reported in which benign lipomas with secondary changes with inflammatory cells stain positive with MDM2 [23] To diminish the challenges of histological diagnosis, P16 immunohistochemistry as an alternative marker combined with the MDM2-FISH immunochemical staining have recently been suggested as a diagnostic method to distinguish WDLS from deep-seated lipoma.[24,26]