The prognostic role of microsatellite instability, codon‐specific KRAS, and BRAF mutations in colon cancer. Issue 4 (25th June 2014)

• Record Type: Journal Article
• Authors: Lin, Chun‐Chi; Lin, Jen‐Kou; Lin, Tzu‐Chen; Chen, Wei‐Shone; Yang, Shung‐Haur; Wang, Huann‐Sheng; Lan, Yuan‐Tzu; Jiang, Jeng‐Kai; Yang, Muh‐Hwa; Chang, Shih‐Ching
• Is Part Of: Journal of surgical oncology. Volume 110:Issue 4(2014:Sep. 15)
• Page Start: 451
• Page End: 457
• Publication Date: 2014-06-25
• Subjects: Cancer -- Surgery -- Periodicals; Neoplasms -- Periodicals; 616
• DOI: 10.1002/jso.23675
• Languages: English
• ISSNs: 0022-4790

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <sec id="jso23675-sec-0001" sec-type="section"> <title>Background</title> <p>This study aimed to establish a correlation between MSI, <italic>KRAS</italic> mutations, and <italic>BRAF</italic><sup><italic>V600E</italic></sup> in colon cancer and to investigate the prognostic effect.</p> </sec> <sec id="jso23675-sec-0002" sec-type="section"> <title>Methods</title> <p>Colon cancer patients who underwent surgical intervention were enrolled. MSI status was identified by genotyping, and the mutational statuses of <italic>KRAS</italic> and <italic>BRAF</italic> were determined by MassARRAY, targeting 22 mutations. The clinicopathological differences and correlations between these factors were analyzed.</p> </sec> <sec id="jso23675-sec-0003" sec-type="section"> <title>Results</title> <p>Among 1, 063 patients, tumors with MSI‐H were significantly associated with <italic>BRAF</italic><sup><italic>V600E</italic></sup> (<italic>P</italic> = 0.001). <italic>KRAS</italic> and <italic>BRAF</italic> mutations were mutually exclusive (<italic>P</italic> = 0.001). Patients with MSI‐H tumors had significantly improved overall survival compared with patients that had microsatellite instability‐low/stable (MSI‐L/MSS) tumors (hazard ratio 0.686: 95% confidence interval: 0.479–1.162, <italic>P</italic> = 0.040). In addition, the <italic>BRAF</italic><sup><italic>V600E</italic></sup> mutation was a poor prognostic factor in tumors with MSI‐L/MSS (<italic>P</italic> = 0.020). <italic>KRAS</italic> mutations were not prognostic factors, but sub‐group analysis demonstrated that mutations in <italic>KRAS</italic> codon 12 were associated with significantly worse survival than wild‐type <italic>KRAS</italic>, mutations in <italic>KRAS</italic> codon 13, or mutations elsewhere.</p> </sec> <sec id="jso23675-sec-0004" sec-type="section"> <title>Conclusions</title> <p>MSI and the <italic>BRAF</italic><sup><italic>V600E</italic></sup> mutation have a prognostic impact in colon cancer. Variable <italic>KRAS</italic> mutations may have different effects on colon cancers; further studies are needed to verify these results. <italic>J. Surg. Oncol. 2014; 110:451–457</italic>. © 2014 Wiley Periodicals, Inc.</p> </sec> </abstract>