Primary tumors arising from different sides of the colon (left versus right) have different clinical outcomes for anti‐EGFR ab plus chemotherapy; patients with RAS wild‐type and left‐sided mCRC benefit more from treatment with cetuximab plus chemotherapy.7 However, at the time of starting this study, the concept of “tumor sidedness for treatment with anti‐EGFR ab” had not yet been established in clinical practice. Here, EGFR is linked to neoplasm.