ERBB2 and head and neck cancer: Trastuzumab (anti-ErbB2 mAb), cetuximab and panitumumab (anti-EGFR mAbs) and rituximab (anti-CD20 mAb) are examples of mAbs of proved efficacy in the treatment of ErbB2+ breast cancers, colorectal carcinomas, head and neck cancers and B-cell cell malignancies, respectively [56,57].