Uptake of clinical genetic testing for ovarian cancer in Ontario: A population-based study

Kelly A. Metcalfe^{a, b, ,} , Isabel Fan^c, John McLaughlin^c, Harvey A. Risch^d, Barry Rosen^e, Joan Murphy^e, Linda Bradley^c, Susan Armel^e, Ping Sun^b and Steven A. Narod^{b a}Lawrence S. Bloomberg Faculty of Nursing, University of Toronto, Toronto, Ontario, Canada ^bWomen's College Research Institute, Toronto, Ontario, Canada ^cMount Sinai Research Institute, Toronto, Ontario, Canada ^dDepartment of Epidemiology and Public Health, Yale University School of Medicine, New Haven, CT, USA ^eDepartment of Gynecology, University Health Network, Toronto, Ontario, Canada

Received 7 August 2008.

Available online 3 December 2008.

Abstract

Background

Approximately 13% of ovarian cancers in Canada are attributable to a mutation in BRCA1 or BRCA2. In 2001, genetic testing for BRCA1 and BRCA2 became freely available to all women in Ontario with a diagnosis of invasive ovarian cancer. It is unknown what proportion of women with ovarian cancer receive genetic testing as a result of this recommendation.

Methods

Patients in Ontario who had been diagnosed with epithelial ovarian cancer from 2002 to 2004 were identified using the Ontario Cancer Registry. Information was collected on demographic and risk factors, including information on previous testing for BRCA1 and BRCA2. Women were asked to provide a blood sample for genetic testing or to provide a genetic test result if clinical testing had been done. Genetic testing for BRCA1 and BRCA2 mutations was conducted on all blood samples.

Results

Of the 416 women, 80 women (19%) had undergone previous clinical genetic testing for BRCA1 and BRCA2. Of these 80 women, 30% had a positive genetic test result, compared to 5% of 336 women who had not had clinical genetic testing (p <>

Conclusions

Genetic testing is available in Ontario to all women with invasive ovarian cancer. However, only a small proportion of women are being referred for testing. This study suggests that increased public awareness directed at physicians and at women with cancer may expand the use of genetic testing.

Keywords: BRCA1; BRCA2; Ovarian cancer; Genetic testing