Forradiologic assessment, early tumour shrinkage (ETS) was suggested as a potentialpredictive marker for long-term outcome in RAS-wt mCRCpatients.16 Still, there are primary anti-EGFR non-respondersin the RAS-wt collective, suggesting heterogeneity in EGFR signalling, anddevelopment of diagnostic tools predicting prognosis and therapy-response is of highinterest. This evidence concerns the gene EGFR and neoplasm.