Building on our prior hypothesis published in the British Journal of Surgery, our institution has investigated potential DNA mutations within the carcinoembryonic antigen-related cell adhesion molecule (CEACAM5) gene's Pro-Glu-Leu-Pro-Lys (PELPK) motif to evaluate its role as a biomarker for liver metastasis risk.<h4>Methods</h4>Partnering with the Australian Genome Research Facility, the PELPK motif of CEACAM5 was analysed in colorectal and appendiceal adenocarcinomas to detect DNA mutations associated with liver metastasis. This evidence concerns the gene CEACAM5 and appendix adenocarcinoma.