|
|
|
|
|
|
|
|
Abstract
An
important proportion of early-onset colorectal cancer (CRC) does not
show a hereditary component, generally Lynch syndrome, 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.
0 comments :
Post a Comment
Your comments?
Note: Only a member of this blog may post a comment.