The first 10 years experience with genetic testing (GT) for BRCA1/2 mutations in a publicly funded program at a tertiary care teaching hospital in Ontario, Canada.

Authors

null

Sherry Athena Doroja Ruste

Sunnybrook Odette Cancer Centre, University of Toronto, Toronto, ON, Canada

Sherry Athena Doroja Ruste , Andrea Eisen , Kathleen I. Pritchard

Organizations

Sunnybrook Odette Cancer Centre, University of Toronto, Toronto, ON, Canada, Sunnybrook Health Sciences Centre; University of Toronto, Toronto, ON, Canada, Odette Cancer Centre, Sunnybrook Health Sciences Centre; University of Toronto, Toronto, ON, Canada

Research Funding

No funding sources reported

Background: Publicly funded testing for BRCA1/2 mutations in Ontario has been available for high-risk individuals since 2000. The criteria are based on personal and/or family cancer history and ethnicity. We reviewed the results of the first 10 yrs of testing at our institution, a regional cancer centre in an academic, tertiary care teaching hospital. Methods: This REB-approved, retrospective study included individuals who had GT from 2001-2011. Sociodemographic, clinical, and GT results were collected. Results: 2,305 individuals met criteria and underwent GT between Jan. 2001and Dec. 2011. Of all tested subjects, 93% were female, median age was 55 yrs., 23% were of Ashkenazi Jewish (AJ) ancestry and 80% lived in an area with family income $50-100K/yr. BRCA1/2 mutations were present in 16%, 8% had unclassified variant (UCV), 76% had normal sequence. We excluded 460 individuals who had predictive GT for a familial mutation, and results are shown in the Table. For each carrier, an average of four additional relatives had GT. The most common criteria for GT was at least three cases of ovarian or breast cancer at any age on the same side of the family. BRCA mutations were most common among those AJ, Italian, Asian Oriental and English ancestry. Wait time for GT result improved from 107 wks. in 2001 to 8 wks. in 2011. Conclusions: In our tested population, the prevalenceof BRCA1/2 mutations was high. Over time wait times improved and more relatives were tested.

Prevalence of mutations excluding predictive testing (N=1,845).
Mutation N %
BRCA1 100 6
BRCA2 74 4
UCV only 171 9
Normal sequence 1,500 81
Cancer history in carriers BRCA1
N
% BRCA2
N
%
No cancer 18 18 12 16
Breast cancer 63 3 53 72
Ovarian cancer 9 9 2 3
Breast and ovarian cancer 5 5 3 4
Other cancer 5 5 4 7
Median age breast cancer diagnosis 42 44
Ancestry in carriers* BRCA1
N
% BRCA2
N
%
Ashkenazi Jewish 26 26 10 13
Italian 16 16 8 11
Asian-oriental 4 4 8 11
Eastern European 5 5 5 7
Asian-other 6 6 4 5

Abbreviations: BRCA, breast cancer; UCV, unclassified variant. *Same ancestry on paternal and maternal side.

Disclaimer

This material on this page is ©2024 American Society of Clinical Oncology, all rights reserved. Licensing available upon request. For more information, please contact licensing@asco.org

Abstract Details

Meeting

2013 ASCO Annual Meeting

Session Type

Poster Session

Session Title

Cancer Prevention/Epidemiology

Track

Cancer Prevention/Epidemiology

Sub Track

Cancer Genetics

Citation

J Clin Oncol 31, 2013 (suppl; abstr 1550)

DOI

10.1200/jco.2013.31.15_suppl.1550

Abstract #

1550

Poster Bd #

3C

Abstract Disclosures

Similar Abstracts

Abstract

2023 ASCO Annual Meeting

The landscape of BRCA1 and BRCA2 alterations in Chinese ovarian cancer patients.

First Author: Minmin Hou

First Author: Natalya N. Timoshkina