Figure 2: Immunohistochemical validation of the newly purified monoclonal antibody against pfetin. A. Immunohistochemical images of pfetin in GIST. B. GIST patients stratified according to the results of immunohistochemistry had significantly different outcomes after surgery. GIST patients in low risk classification (C) and those in high risk classification (D). Immunohistochemistry was achieved according to our previous reports [9-11].