Differential clinicopathological and molecular features within late-onset colorectal cancer according to tumor location

Brandariz, LorenaArriba, MaríaGarcía, Juan LuisCano, Juana MaríaRueda, DanielRubio, EduardoRodríguez, YolandaPérez, JessicaVivas, AlfredoSánchez, CarmenTapial, SandraPena, LauraGarcía-Arranz, MarianoGarcía-Olmo, DamiánUrioste, MiguelGonzález-Sarmiento, RogelioPerea, José2019-09-232019-09-232018-03-16Oncotarget. 2018 ;9(20):15302-15311.1949-2553http://hdl.handle.net/20.500.12105/8364Background: Since there is a predilection of some clinical and molecular features for a given tumor location, we assessed whether this can be confirmed in late-onset colorectal cancer (LOCRC). Results: Right colon cancers showed features associated with sporadic Microsatellite Instability: predominance of female cases and BRAF mutations, and an important mucinous component. Left colon cancers developed a higher number of polyps and multiple primary CRCs, showed the strongest familial component, and had better prognosis. Rectal cancers showed a predominantly sporadic phenotype, with worse prognosis and a CpG Island Methylator Phenotype (CIMP)-High. No copy number alterations (CNAs) greater than or equal to 50% were observed in this LOCRC group, and the most recurrent alterations were losses at 5q13 and 14q11, and gains at 7q11, 7q21-q22, 19p13-p12, 19q13 and 20p11-q11. KRAS and PIK3CA were the only mutated genes showing differences according to the tumor location, mainly for right colon cancers. Materials and Methods: We analyzed clinical and molecular characteristics of LOCRC at different tumor locations in order to determine if there are differential phenotypes related with the location in the colon. Conclusions: Categorizing LOCRC according to tumor location appears to be an adequate first step to resolving the heterogeneity of this subset of CRC.engVoRhttp://creativecommons.org/licenses/by-nc-sa/4.0/CpG island methylator phenotypechromosomal instabilitycolon locationlate-onset colorectal cancermicrosatellite instabilityDifferential clinicopathological and molecular features within late-onset colorectal cancer according to tumor locationAtribución-NoComercial-CompartirIgual 4.0 Internacional2963264592015302-1531110.18632/oncotarget.245021949-2553Oncotargetopen access