Identification of cells with BRAF mutation. Immunohistochemistry with BRAFV600E specific antibody VE1 disclosed cytoplasmic staining of histiocytes, whereas lymphocytes and fibroblasts were negative (top, original magnification ×100). Some histiocytes were not stained and correspond to reactive macrophages (bottom, original magnification ×200). Microphotographs were performed with a microscope BX41, eyepiece (WH 10×/22), objectives Olympus UPlanFI 10× and Olympus UPlanFI 20× (Olympus), Camera Axopcam ICc1, and AxioVision Rel Version 4.8 software (Carl Zeiss).