Human angiosarcoma is a rare, rapidly growing sarcoma, which is highly invasive and arises from endothelial cells.32 Having demonstrated that mouse-deregulated TCL1b expression resulted in angiosarcoma, we next examined human angiosarcoma tissues by immunostaining with anti-TCL1b or phospho-Akt antibodies. The gene discussed is AKT1; the disease is angiosarcoma.