ERBB2 and neoplasm: In particular, while the anti-HER2 agent pertuzumab, when given alone or in association with cetuximab, induced only a negligible delay in tumor growth, the combination of lapatinib (a dual EGFR/HER2 tyrosine kinase inhibitor) and pertuzumab or, at a lesser extent, of lapatinib and cetuximab caused a significant and durable tumor shrinkage.