Age

18–75

Sex

ALL

Healthy volunteers

Not accepted

Cytological or histological diagnosis of RAS mutated mCRC;
progression at first-line chemotherapy with fluoropyrimidines, oxaliplatin and bevacizumab;
stage IV;
age \<75 years;
ECOG Performance Status 0 or 1;
life expectancy\> 3 months;
negative pregnancy test for all potentially childbearing women.

presence of primary non-treated stenosing colorectal neoplasm;
active or uncontrolled infections or bleedings;
other concomitant uncontrolled diseases or blood laboratory values contraindicating the study drugs at clinician evaluation;
presence of brain metastases;
refusal or inability to provide informed consent;
impossibility to guarantee follow-up.

Aflibercept or Bevacizumab as Second-line Treatment of RAS Mutated Metastatic Colorectal Cancer