Given that TP53-deficient mice developed severalspontaneous tumors including angiosarcoma, another malignant vascular tumor, TP53mutation may play a role in the tumorigenesis of vascular tumors.8 However, since this SNV is seen inabout 60% of the population, there is a possibility that "second-hit" somaticmutation is also necessary for tumorigenesis. The gene discussed is TP53; the disease is angiosarcoma.