TP53 and angiosarcoma: Somatic alterations consistent with sporadic angiosarcoma: oncogenic NRAS:c.181C>A (p.Gln61Lys); TP53:c.404G>A (p.Cys135Tyr); two-copy deletion of CDKN2A and CDKN2B at 9p21.3; two-copy deletion of TSC2 at 16p13.3; single copy deletion of TP53 at 17p13.1; tumor is likely sporadic, no germline driven LOH