However, recent experimental results showing that the F(ab')2 fragments of anti-EGFR and anti-HER2 mAbs could significantly inhibit the growth of pancreatic carcinoma xenografts in nude mice, clearly demonstrate that at least part of the anti-tumour effect is not ADCC mediated and must be due to binding of the F(ab')2 fragments to the sensitive HER1 and HER2 receptors [32]. This evidence concerns the gene ERBB2 and exocrine pancreatic carcinoma.