KRAS and neoplasm: Thus, although EGFR-targeted therapies are ineffective, and might be harmful, in KRAS mutant tumours,20, 21, 24, 27 response of metastatic KRAS wild-type colonic tumours is clearly increased by adding anti-EGFR therapies to chemotherapy, suggesting potential benefits as an adjuvant to preoperative oxaliplatin-based chemotherapy in operable disease.