By analyzing the AACR GENIE dataset, we identified recurrent alterations in pathways central to angiosarcoma, including TP53, VEGF (KDR/FLT4), and PI3K (PIK3CA), as well as tumor suppressors such as ATM and ARID1A, chromatin remodelers like KMT2D, and regulators of contact inhibition such as FAT1. This evidence concerns the gene ARID1A and neoplasm.