BRAF-V600E in colorectal cancer

Synopsis

 Excluding Lynch syndrome

• In colorectal carcinoma, the presence of the BRAFV600E mutation can be used to virtually exclude Lynch syndrome in mismatch repair-deficient tumors.
• Immunohistochemistry Facilitates Universal Screening of Colorectal Cancers for Lynch Syndrome. (23797718)
• BRAFV600E mutation in microsatellite-unstable (MSI) colorectal carcinomas (CRCs) virtually excludes Lynch syndrome (LS).

 Prognostic biomarker

• In mismatch repair-proficient tumors, BRAFV600E mutation assessed by molecular methods has been proposed as a poor prognostic factor.
• BRAFV600E and mismatch repair assessment by immunohistochemistry can be used as a powerful predictor of all-cause survival. (24157612)
• In microsatellite-stable (MSS) CRCs it predicts poor prognosis.
• BRAF IHC is highly concordant with 2 commonly used PCR-based BRAFV600E assays.

 Joined BRAF MMR testing

• It performed well in identifying MLH1 mutation carriers from the ACCFR and identified all cases of proven LS.
• Reflex BRAFV600E and MMR IHC are simple cheap tests that facilitate universal LS screening and identify the poor prognosis of the BRAFV600E-mutant MSS CRC phenotype.
• BRAFV600E immunohistochemistry in conjunction with mismatch repair status predicts survival in patients with colorectal cancer. (25153715)

Open References

 BRAFV600E immunohistochemistry in conjunction with mismatch repair status predicts survival in patients with colorectal cancer. Toon CW, Chou A, DeSilva K, Chan J, Patterson J, Clarkson A, Sioson L, Jankova L, Gill AJ. Mod Pathol. 2014 May;27(5):644-50. doi : 10.1038/modpathol.2013.200 PMID: 24157612 [Free]

References

 Detection of the BRAF V600E mutation in colon carcinoma: critical evaluation of the imunohistochemical approach. Lasota J, Kowalik A, Wasag B, Wang ZF, Felisiak-Golabek A, Coates T, Kopczynski J, Gozdz S, Miettinen M. Am J Surg Pathol. 2014 Sep;38(9):1235-41. doi : 10.1097/PAS.0000000000000229 PMID: 24832158 (Paywall)