Abstract
Genetic diagnosis for human epidermal growth factor receptor 2-negative metastatic breast cancer patients with the germline BRCA (gBRCA) mutation has been emphasized since the development of polyadenosine diphosphate-ribose polymerase inhibitors. Myriad Genetics, Inc.’s (Salt Lake City, UT, USA) companion diagnostics service is almost exclusively used for genetic testing. The aim of this study was to compare the results of germline BRCA mutation tests returned by a local laboratory and those performed by Myriad. Between April 2014 and February 2018, 31 patients with gBRCA 1/2 mutation test results from both Samsung Medical Center (Seoul, Korea) and Myriad were enrolled. “Discordant: Opposite classification” was observed for only one among 27 (3.7%). This discrepancy was due to the detection of a deleterious large genomic rearrangement of BRCA 1 by Myriad. Samsung Medical Center performed multiple ligation-dependent probe amplifications (MLPA) to detect large genomic rearrangements only in high-risk patients. This one case was not suspected as high risk and MLPA was not performed. The concordant rate was 74.1% for all 27 patients. “Discordant: Laboratory’s uncertain classification” was found in 22.2% of the sample (six patients). All discrepancies were generated during interpretation of BRCA 2 gene sequencing. Further studies and standardization of genetic testing for BRCA 1/2 genes are required.
Highlights
Breast cancer is a leading cause of cancer and cancer-related death in women worldwide [1]
We compared germline BRCA (gBRCA) 1/2 mutation test results obtained by a local reference laboratory and by Myriad, which offers a commercial test that is commonly used all over the world
Such testing would help researchers to determine the regional prevalence of gBRCA 1/2 mutations, provide easier accessibility to mutation testing for people who are at risk of being gBRCA 1/2 mutation carriers and eventually treat breast cancer patients who have gBRCA 1/2 mutations with polyadenosine diphosphate-ribose polymerase (PARP) inhibitors
Summary
Breast cancer is a leading cause of cancer and cancer-related death in women worldwide [1]. Breast cancer consists of various types of cancer. Most breast cancer is sporadic, hereditary breast cancer comprises up to 10% of cases [2]. BRCA 1/2 genes are tumor suppressor genes that contribute to DNA repair and protect DNA from damage [3]. Mutated BRCA 1/2 genes are known to cause breast cancer. Carriers of germline BRCA 1 and germline BRCA 2 mutations have 65% and 45% chances of developing breast cancer by age 70, respectively [4]. Due to the number of breast cancer patients with germline BRCA (gBRCA) mutations, genetic risk assessment and counseling, and specific treatments for breast cancer patients with gBRCA mutations, are increasingly emphasized [5]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
