Intravascular fasciitis involving the external jugular vein and subclavian vein: A case report

Figure 3 Immunohistochemistry and USP6 gene rearrangement. A: The spindle cells were positive for smooth muscle actin; B: The spindle cells were positive for vimentin; C: The spindle cells were positive for caldesmon; D: Ki-67 staining of spindle cells revealed a low proliferative index (5%-10%); E: The spindle cells were negative for CD34; F: The spindle cells were negative for S-100; G: The spindle cells were negative for desmin; H: The spindle cells were negative for c-kit; I: Fluorescence in situ hybridization with a separate probe for USP6 indicated that there might be one yellow or red-green adjacent fusion signal and two red-green separation signals in most cells.