PROJECTED ACCRUAL: A total 600 patients (300 per treatment arm) will be accrued for this study within 3 years. Assuming median progression-free survivals of 16 months and 21 months and a recruitment period of 3 years this can be achieved by recruiting 600 patients designed to have 80 % detect to a difference between the two arms at the two-sided 5% level of statistical significance.