[Chemotherapy of metastatic colorectal cancer]

Increasing numbers of therapeutic options are becoming available for the systemic treatment of metastasized colorectal cancer (mCRC) which emphasizes the need for strategic decision making and planning across multiple lines of treatment. The choice of first-line therapy is influenced by clinical and molecular characteristics of patients and tumors, such as (K-)RAS gene mutations with respect to therapy guidance of epidermal growth factor receptor (EGFR) antibodies. First-line therapy is the major determinant of subsequent treatment regimens and can therefore be considered as the key decision in patients with mCRC. The German standard for first-line therapy in the majority of patients includes chemotherapy in combination with biological agents, with antibodies targeting EGFR possibly being the preferable option in patients with (K-)RAS wild-type tumors. The development of effective therapeutic strategies in patients with (K-)RAS mutant mCRC tumors must be promoted in the future and requires intensive research because the therapy options for this group of patients are very limited.