Lay Summary: BART testing is a new twist on BRCA testing.
BART stands for BRACAnalysis Rearrangement Test, which detects large DNA rearrangements in the BRCA1 and BRCA2 genes, which the pcr for BRCA does not detect. Myriad’s postion is that BART testing is appropriate for women who have had full sequence analysis for BRCA 1/2, have tested negative and are at very high baseline risk. Myriad quotes the following statistics: when baseline risk of BRCA is 30%, BART will be _ in 2-3% or women. however, if you look at all + tests results, 10% of them are in the form of BART. Based on clinical and family history criteria, 1,035 patients were identified as severe-risk during the initial months of clinical BART analysis at Myriad Genetic Laboratories. All patients were initially tested for Comprehensive BRACAnalysis which includes BRCA1 and BRCA2 full gene sequencing plus large rearrangement panel testing for 5 recurrent BRCA1 mutations. Among severe-risk patients, 302 (29.2%) were positive for a BRCA1 or BRCA2 mutation by sequencing, 9 (0.9%) were positive by large rearrangement panel testing and an additional 27(2.6%) tested positive by BART for large genomic rearrangements. The total detection rate for deleterious mutations in severe-risk individuals was therefore 32.7%. As of August 1, 2006, Myriad conducts the BRACAnalysis Rearrangement Test on patient samples where the individual’s personal and family history is indicative of an exceptionally high level of risk, but the sample tests negative for BRACAnalysis. The Rearrangement test will be performed, when indicated, at no additional charge, and is also available for order independently for a fee of $650.
In a 2011 review, Shannon et al recommended routine testing of all BRCA testing women but many cosndiered it over-reaching since only 1.9% of the sample had this mutation.
Recently NCCN updates its recommendations based on a new paper in Cancer. NCCN now defines comprehensive genetic testing to include large genomic rearrangements. Previously, the guidelines noted that large genomic rearrangements are not detectable by primary sequencing, but did not specify that additional testing (i.e. BART) should be included as part of comprehensive testing. This is based on new data that large genomic rearrangements account for 6-10% of BRCA1 and BRCA2 mutations. In individuals of Latin American/Caribbean and Near East/Middle East descent, these rearrangements account for approximately 20% of mutations. The following will meet the NCCN criteria for BART testing:
Patient affected with breast cancer before aged 50 AND family history of 2 or more cases of breast cancer before age 50 and/or ovarian cancer at any age.
- Ovarian cancer at any age AND family history of 2 or more cases of breast cancer before age 50 and/or ovarian cancer at any age.
- Male breast cancer at any age AND family history of 2 or more cases of breast cancer before age 50 and/or ovarian cancer at any age.
- Breast cancer at or after 50 and ovarian cancer at any age AND family history of 1 or more cases of breast cancer before age 50 and/or ovarian cancer at any age.
Emily Z. TouloukianUsefulness of Retrospective Analysis of BART Eligibility The Open Breast Cancer Journal,2012, 4, 2012
R. Wenstrup, T. Judkins, K. Eliason, J. Schoenberger, S. Rajamani, C. A. A. Frye, L. A. Burbidge, J. T. Trost, A. M. Deffenbaugh, B. B. Ro Molecular genetic testing for large genomic deletion and duplication mutations in the BRCA1 and BRCA2 genes for hereditary breast and ovarian cancer. Journal of Clinical Oncology, 2007 ASCO Annual Meeting Proceedings Part I. Vol 25, No. 18S (June 20 Supplement), 2007: 10513
Thaddeus Judkins, et al, Clinical Significance of Large Rearrangements in BRCA1 and BRCA2, Cancer 2012;000:000–000
Shannon KM, Rodgers LH, Chan-Smutko G, Patel D, Gabree M, Ryan PD. Download BART_article_2012Which individuals undergoing BRACAnalysis need BART testing?Cancer Genet. 2011 Aug;204(8):416-22.
Wendy Rubinstein Roles and responsibilities of a medical geneticist. Fam Cancer. 2007 Jul 12; : 17624600