Patients with mCRC originating from right-sided tumours are reported to display a worse overall survival (OS) compared to left-sided tumours and retrospective analyses of the CALGB-80405 and FIRE-3 studies demonstrated a predictive value of the primary tumour localization and the choice between anti-vascular endothelial growth factor (VEGF) and anti-EGFR based systemic therapy in mCRC [2, 8–10]. The gene discussed is EGFR; the disease is neoplasm.