The results of the CAIRO3 study by Dr. Mirian Koopman and others at Utrecht University Medical Center in the Netherlands showed that maintenance treatment with capecitabine in combination with bevacizumab prolonged progression-free survival in patients with metastatic colorectal cancer. According to Dr. Mirian Koopman, they have finally found the answer to the question, “Should I continue chemotherapy in combination with bevacizumab or should I stop treatment,” and maintenance therapy is a way to give patients better survival without compromising their quality of life. Despite the proliferation of new drugs that have improved the prognosis of patients with metastatic colorectal cancer, the appropriate use of drugs and the choice of treatment regimens are still up in the air. Dr. Koopman and her colleagues at the Dutch Colorectal Cancer Group conducted an open randomized clinical study. The study compared 588 patients with metastatic colorectal cancer receiving capecitabine in combination with bevacizumab as maintenance therapy or observation alone. All enrolled patients received 6 cycles of capecitabine + oxaliplatin + bevacizumab regimen (CAPOX-B) prior to inclusion in the study and had no disease progression at post-treatment review. After the first disease progression (PFS1), all patients received chemotherapy with the same induction regimen (CAPOX-B) until the second disease progression (PFS2). The primary study endpoint in this study was the patients’ second disease progression. The median PFS1 was significantly longer in the maintenance treatment group than in the observation group (8.5 months vs. 4.1 months), and similarly, PFS2 was significantly longer in the maintenance treatment group than in the observation group (11.7 months vs. 8.5 months). In terms of overall survival, the median overall survival time was longer in the maintenance group than in the observation group (21.6 months vs. 18.1 months), but the difference between the two did not reach statistical significance. The rate of adverse events, such as hand-foot syndrome, was significantly higher in the maintenance group than in the observation group, but this did not lead to clinical differences in overall quality of life between the groups. The investigators concluded that maintenance therapy with capecitabine combined with bevacizumab should be the preferred treatment option for patients with metastatic colorectal cancer whose disease has stabilized or improved after initial treatment with chemotherapy combined with bevacizumab. According to Dr. Koopman, maintenance therapy should be maintained for as long as possible. However, if patients experience intolerable toxic side effects, then treatment should be discontinued. Since it is palliative treatment, all patients will eventually experience disease relapse. Future research directions should consider whether some observation alone is more appropriate for subgroups of patients. Axel Grothey, MD, of the Mayo Clinic, USA, believes that among colorectal cancer patients whose first-line treatment regimen includes bevacizumab, he would recommend maintenance therapy for most. He said the future of treatment lies in better analysis of patients’ tumors and being able to develop specific targeted drugs accordingly. In the present, non-specific drugs like TAS-102, which has been shown to improve overall survival in colorectal cancer patients, will be integrated into the existing treatment paradigm. A subset of patients, such as those with what is known as hypermutated colorectal cancer, may also benefit from immunotherapy. The strategy of treatment modality selection and the prospective management of toxicities are significant for maximizing the prognosis of colorectal cancer patients.