- Arm II: Patients receive oral low-dose celecoxib twice daily. In both arms, treatment continues until first disease progression. At disease progression, treatment assignment is unblinded and treatment may continue at the treating physician's discretion. Patients initially randomized to the low-dose arm may either continue on that dosage or crossover to the high-dose arm. Patients initially randomized to the high-dose arm may continue on that dosage. Treatment after disease progression may continue for up to 12 months.