Abstract: Chemotherapy with or without moleculetargeting agents is the primary choice for patients with unresectable metastatic colorectal cancer. New treatment strategies like intermittent therapy and maintenance therapy may not inferior to treatment until progression or unacceptable toxicity in maintaining the benefit for patients who responded or had stable disease after the firstline therapy, and also can reduce the drug related side effects and improve the quality of life.

Key words: Colorectal neoplasms, Metastases, Drug therapy