Surgical therapy, often combined with adjuvant systemic chemotherapy, is the best therapeutic option to treat patients with colorectal liver metastasis (CRLM), with postoperative 5-year survival ranging from 40% to 50%.
1,2 However, while overall survival (OS) has improved, many patients with CRLM will recur and ultimately die of their disease.
1,3 The factors used to predict outcome following surgical resection of CRLM largely focus on clinicopathological prognostic factors such as preoperative carcinoembryonic antigen (CEA) level, presentation of disease (ie, synchronous vs metachronous disease), disease-free interval between primary tumor and hepatic metastasis, and metastatic tumor number and size.
4 There has been increasing interest in the use of biologic and molecular markers in the prognostic assessment of patients with metastatic colorectal cancer undergoing liver resection.
4 Among patients with colorectal adenocarcinoma, mutated Kirsten rat sarcoma viral oncogene homolog (
KRAS) is the most common oncogene of the RAS family, reported in up to 30% to 40% of patients.
5-9 While the frequency and prognostic impact of
KRAS mutation status have been described for both primary and metastatic colorectal cancer, to our knowledge, the role of specific mutations on
KRAS codons remains undefined.
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