Our analysis largely captures the landscape of hotspot mutations in canine tumors, which are similar to the mutational landscapes reported by previous whole exome or genome sequencing studies (e.g., TP53, NRAS and PIK3CA mutations in hemangiosarcoma, TP53 and SETD2 mutations in osteosarcoma, ERBB2 mutation in pulmonary carcinoma, BRAF mutation in urothelial carcinoma and FBXW7 mutation in lymphoma)18,20,22–27,29,35–38,49,50. Here, PIK3CA is linked to urothelial carcinoma.