Maintenance Treatment Versus Observation After Induction in Advanced Colorectal Carcinoma

Standard 1st-line treatment for patients with advanced colorectal cancer currently consists of chemotherapy plus bevacizumab. With this approach the median overall survival is approximately 20 months, and progression-free survival in first-line approximately 9-11 months. The optimal duration of treatment is unknown. Current data suggest that the efficacy of bevacizumab is dependent on concomitant use of chemotherapy. However, oxaliplatin almost invariably gives rise to neuropathy after 6-8 cycles. Prolonged use of capecitabine is associated with e.g. hand-foot syndrome. Lastly, the prolonged use of these agents is associated with considerable costs. Evidence, mainly preclinical, suggests that continuous dosing metronomic chemotherapy may be more efficacious than interval-chemotherapy given at MTD. In this study the concept of metronomic chemotherapy is explored by administering a continuous daily instead of the usual 2 weeks-on/1 week-off oral dosing regimen of low-dose capecitabine plus bevacizumab as maintenance therapy after induction combination chemotherapy given at MTD plus bevacizumab.