The pathogenesis of angiosarcoma is probably also related to other genes, including CIC gene rearrangement,[37] increased expression of the MYC gene[38] and FLT-4 gene,[37] and mutations of PTPRB and PLCG1,[1,39–43] but the present study focused on the PD-1/PD-L1 and PI3K/mTOR signaling pathways. The gene discussed is PIK3CA; the disease is angiosarcoma.