Frequently mutated genes in CRC were detected in both primary PDOs and metastatic PDOs (Figures 1 and S2), including APC (91%), TP53 (79%), KRAS (56%), FBXW7 (19%), PIK3CA (11%), NRAS (9%), TCF7L2 (9%), SMAD4 (9%), and BRAF (8%). The gene discussed is PIK3CA; the disease is colorectal carcinoma.