Patients were assessed before randomization, every two weeks during treatment, and then every six months for five years. The baseline assessment involved a medical history taking, physical examination,
biologic tests, measurement of the carcinoembryonic antigen level, chest radiography, and abdominal ultrasonography or computed tomography.Patients were monitored for adverse effects throughout the treatment period and until 28 days after the last cycle of chemotherapy, unless treatment-related adverse effects required additionalfollow-up.