SMN1 and gastrointestinal stromal tumor: The histological structure of schwannomas shows spindle cells that form fascicles, which intersect while showing nuclear palisading in Antoni A areas and hypocellular regions in Antoni B. The distinctive feature of these tumors remains their scattered S-100 protein expression together with their absence of CD117, DOG-1, desmin and SMA markers, which differentiates them from gastrointestinal stromal tumors [6].