Age at onset should be a major criterion for subclassification of colorectal cancer.

Abstract

An important proportion of early-onset colorectal cancer (CRC) does not show a hereditary component with limited knowledge about its molecular basis and features. We analyzed a subset of patients with early-onset CRC and compared them with patients with late-onset CRC. We analyzed the microsatellite instability and CpG island methylator phenotype (CIMP) in both populations and classified them into four molecular subtypes. We analyzed the differential features between groups. Only 12 of 81 early-onset cases (15%) showed microsatellite instability, 10 of which (83%) were Lynch syndrome cases; microsatellite instability cases in elderly patients were sporadic. Early-onset microsatellite-stable cases showed different tumor locations and more family history of cancer than the elderly. Microsatellite instability/CIMP-high early-onset CRC was associated with Lynch syndrome, whereas the elderly cases were associated with BRAF mutations. Early-onset microsatellite-stable/CIMP-high CRCs were more frequently mucinous and right sided than elderly cases, with a high incidence of Lynch syndrome neoplasms; early-onset microsatellite stable/CIMP-low/0 differed from elderly cases in location, stages, incidence of multiple primary neoplasms, and the familial component. The clinical and familial differences observed between early- and late-onset CRC when considering the different carcinogenetic pathways underline that the age at onset criterion should be considered when classifying CRC.

• Authors: José Perea, Daniel Rueda, Alicia Canal, Yolanda Rodríguez, Edurne Álvaro, Irene Osorio, Cristina Alegre, Bárbara Rivera, Joaquín Martínez, Javier Benítez, Miguel Urioste
• Journal: The Journal of molecular diagnostics : JMD (J Mol Diagn) Vol. 16 Issue 1 Pg. 116-26 (Jan 2014) ISSN: 1943-7811 [Electronic] United States
• PMID: 24184227 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2014 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

Chemical References

• BRAF protein, human
• Proto-Oncogene Proteins B-raf

Topics

• Adult
• Age of Onset
• Aged
• Colorectal Neoplasms (classification, epidemiology, genetics)
• CpG Islands (genetics)
• Female
• Humans
• Male
• Microsatellite Instability
• Microsatellite Repeats (genetics)
• Middle Aged
• Proto-Oncogene Proteins B-raf (genetics)