Patients in both groups received up to six 3-week cycles of intravenous cisplatin (100 mg/m(2) on day 1 of each cycle) and fluorouracil (1000 mg/m(2) on days 1-4 of each cycle); those in the experimental group also received intravenous panitumumab (9 mg/kg on day 1 of each cycle)....Median overall survival in patients with p16-negative tumours was longer in the panitumumab group than in the control group (11·7 months [95% CI 9·7-13·7] vs 8·6 months [6·9-11·1]; HR 0·73 [95% CI 0·58-0·93]; p=0·0115), but this difference was not shown for p16-positive patients (11·0 months [7·3-12·9] vs 12·6 months [7·7-17·4]; 1·00 [0·62-1·61]; p=0·998).