UNASSIGNED: RAS and @entity817 mutations impact treatment and prognosis of metastatic @entity14 @entity1 (mCRC), but the knowledge is based on trial @entity1 usually not representative for the general @entity5 population. @entity1 characteristics, treatment and efficacy according to @entity984 , @entity817 and MSI status were analyzed in a prospectively collected unselected population-based cohort of 798 non-resectable mCRC @entity1 . The cohort contained many @entity1 with poor performance status (39% @entity7989 ) and elderly (37% age>75), groups usually not included in clinical trials. @entity1 without available @entity3145 ( @entity3145 ) (42%) had worse prognostic factors and inferior survival (all @entity1 ; 7m vs 11m, chemotherapy-treated;12m vs 17m). The 92 @entity1 (21%) with @entity817 mutation had a poor prognosis regardless of microsatellite instability, but receipt of 1-2nd chemotherapy was similar to wildtype @entity817 @entity1 . Median survival in this cohort varied from 1 month in @entity817 mutated @entity1 not given chemotherapy to 26 months in wildtype @entity984 / @entity817 @entity1 <75 years in good PS. @entity3145 availability, @entity817 mutation and @entity984 mutation were all independent prognostic factors for survival. The observed 21% @entity817 mutation incidence is higher than the previously and repeatedly reported incidence of 5-12% in mCRC. Screening for @entity817 mutations before selection of treatment is relevant for many @entity1 , especially outside clinical trials. A @entity817 mutation only partly explained the very poor prognosis of many mCRC @entity1 . Survival in unselected metastatic @entity14 @entity1 is extremely variable and subgroups have an extremely short survival compared to trial @entity1 . @entity1 without available @entity3145 had worse prognostic factors and shorter survival, which questions the total generalizability of present @entity3145 studies and implies that we lack information on the biologically worst mCRC cases. Lack of available tissue is an important underexposed issue which introduces sample bias, and this should be recognized more clearly when conclusions are made from translational mCRC studies.

High @entity817 Mutation Frequency and Marked Survival Differences in Subgroups According to @entity984 / @entity817 Mutation Status and XXXX Tissue Availability in a Prospective Population-Based Metastatic @entity14 Cohort.

@entity1 :: ('9606', 'Species') :: ['Patients', 'patients', 'Patient'] @entity3145 :: ('MESH:D017695', 'Disease') :: ['tissue micro array', 'TMA'] @entity984 :: ('3845', 'Gene') :: ['KRAS'] @entity5 :: ('MESH:D009369', 'Disease') :: ['cancer'] @entity14 :: ('MESH:D015179', 'Disease') :: ['colorectal cancer'] @entity817 :: ('673', 'Gene') :: ['BRAF'] @entity7989 :: ('5627', 'Gene') :: ['PS 2-4']
@entity5 :: (MESH:D009369,Disease) :: ['Tumor']
