Moreover, while several clinical studies have suggested that the tumour location does not predict benefit from bevacizumab treatment in patients with mCRC harbouring KRAS wt16,29 and undetermined RAS status30, other reports indicate better outcomes in left- than right-sided mCRC, with unselected RAS status, treated with bevacizumab13,17,30. Here, KRAS is linked to neoplasm.