Dr. Fouad Al Daniel completed his MBBS at King Faisal University, College of Medicine in Dammam, Saudi Arabia in 1985. In 1993, he obtained Fellowship of the Royal College of Pathologists of Australasia (FRCPA). Currently, he is the Chairman of the Department of Pathology at King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia. Also, he the Deputy International Commissioner for the Middle East, College of American Pathologists. As Consultant Pathologist, his special interest is in lung pathology, bone pathology, and molecular pathology. Dr. Al Dayel main research interest is cancer genome. He has a total of 133 scientific publications in reputed journals and 169 abstracts.
Colorectal cancer (CRC) is one of the most common cancers in the world. A newly proposed integrated pathway comprising traditional, alternate, and serrated pathways by genetic and epigenetic factors was defined recently and hypothesized to play a role in the pathogenesis of CRC. There is a paucity of information regarding these proposed molecular pathways in different ethnic groups.
Molecular characterization of 770 CRC specimens was performed for microsatellite instability, BRAF, and KRAS by polymerase chain reaction and 500 cases for CpG island methylator phenotype (CIMP) high phenotype by MethyLight technology. Tumors were assigned to different molecular pathways and examined for clinicopathological correlation and survival analysis.
The traditional pathway constituted 33.4% of CRC cases, the alternate pathway comprised 11.6%, and the serrated molecular pathway accounted for only 0.8% of Middle Eastern CRC cases.
Approximately 54.2% of CRC cases did not qualify to fit into any pathway and thus were designated as an unassigned group.
The serrated pathway was found to account for a very low percentage of the CRC patient cohort in the current study. The unassigned group accounted for the majority of Middle Eastern CRC cases, and therefore methods of CRC pathway analysis might not be applicable to this ethnic group. The current study demonstrates the need to unravel the molecular genetic basis of this disease to further subcategorize these CRC cases.
Middle East; alternate pathway; colorectal cancer; molecular pathways; serrated pathway; traditional pathway