The tyrosine kinase inhibitor, gefitinib, is targeted against EGFR and is being used in clinical trials with objective responses of antitumour activity being noted in non-small-cell lung cancer, squamous cell carcinoma of the head and neck and in hormone-refractory prostate cancer (Baselga and Averbuch, 2000; de Bono and Rowinsky, 2002). Here, EGFR is linked to squamous cell carcinoma.