F13A1 and dermatofibrosarcoma protuberans: It has been reported that 92–100% of DFSP cases usually show diffuse CD34 staining, can be positive for vimentin, nestin and apolipoprotein D, and can be negative for cytokerins, smooth muscle actin smooth muscle actin, S100, CD56, factor XIIIa, Stromelysin 3 and cathepsin K [24, 25, 42].