ACTA1 and gastric leiomyosarcoma: The combination of spindle cell morphology, α-SMA and h-caldesmon positivity, CD117 and DOG1 negativity, and high mitotic activity is consistent with the typical profile of gastric leiomyosarcomas and allows differentiation from GISTs, which usually express CD117, DOG1, and frequently CD34 [6,7,10,11].