SMAD4 and colorectal carcinoma: Mutations in ATM, KIT, PIK3CA, and SMAD4 have frequently been found in CRC with synchronous LM, and FBXW7, SMO, and STK11 were frequently mutated in CRC with metachronous LM; CDKN2A, FGFR2, GNAS, JAK3, and SRC were mutated only in metachronous LM [37].