The study is a two-arm randomised phase III trial. Patients will be randomised to receive capecitabine (arm A) or S-1 (arm B). Bevacizumab may be added according to the choice of the investigator. Patients will be followed 3-weekly at the outpatient clinic, toxicity will be assessed according to study protocol guidelines. Patients will be evaluated every 3 cycles for response. Upon disease progression patients will be treated according to the local investigators