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for evaluation RAS status. In addition to anti-EGFR therapy consideration and prognostification, BRAF
mutation is now the target for combination BRAF inhibitors. Other biomarkers such as HER2, RTK
rearrangement or rare potential emerging targets were considered as beyond standard biomarkers. With
the increasing number of required biomarkers in mCRC management, multiplex gene panel testing is now
replacing single gene testing strategy. Of those patients accessible to matched molecular targeted therapy,
especially for clinical trials, CGP might be the preferred testing method. Liquid biopsy is not yet clinical
applicable in mCRC, but there is potential benefit of the detection of drug resistance and dynamic change
of biomarker status. The current application of biomarkers in mCRC was summarized in Table 1.

DECLARATIONS
Authors’ contributions
Responsible for the paper, concept, design, literature search, and manuscript preparation, manuscript
editing, manuscript revision: Tanasanvimon S

Availability of data and materials
Not applicable.

Financial support and sponsorship
None.

Conflicts of interest
The author declared that there are no conflicts of interest.

Ethical approval and consent to participate
Not applicable.

Consent for publication
Not applicable.

Copyright
© The Author(s) 2018.

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