Anti-EGFR and Anti-VEGF Agents in First-Line Therapy for Advanced Colorectal Cancer

Outcomes for metastatic colorectal cancer have improved progressively with the incorporation of new drugs into standard treatment regimens. Most recently, targeted therapies against VEGF and EGFR have improved upon the prior standard for first-line therapy with FOLFOX or FOLFIRI. As attempts to combine anti-VEGF and anti-EGFR drugs have been unsuccessful, it is necessary to choose between them when beginning first-line therapy. This review summarizes the existing literature to best inform this decision. To date, three head-to-head trials have compared anti-EGFR and anti-VEGF therapy in RAS wild-type patients: PEAK, FIRE-3, and CALGB/SWOG 80405. PEAK and FIRE-3 suggested a survival advantage for anti-EGFR therapy over anti-VEGF therapy, though CALGB/SWOG 80405 did not. Results have emerged recently to suggest that tumors arising from the right colon are resistant to anti-EGFR therapy, and that any advantage of anti-EGFR therapy over anti-VEGF therapy may be limited to left-sided tumors.