Hereditary breast and ovarian cancer (germline)
Also known as: familial breast cancer, BRCA, familial ovarian cancer, serous cancer, hereditary breast and ovarian cancer (HBOC), ATM, BRCA1, BRCA2, BRIP1, CDH1, CHEK2, MLH1, MSH2, MSH6, PALB2, PMS2, PTEN, RAD51C, RAD51D, STK11, TP53.
Familial - Familial cancer; Oncology- Breast/Ovarian cancer
Use of test
A proportion of individuals with a diagnosis or family history of breast or ovarian cancer has a hereditary predisposition to develop these cancers due to variants in any one of several genes. The purpose of testing these genes can be categorised as follows:
- diagnostic testing of multiple genes in an affected person to make a diagnosis of hereditary breast/ovarian cancer
- in selected circumstances, case finding may be warranted i.e. testing of multiple genes in an unaffected person to make a diagnosis of a predisposition to hereditary breast/ovarian cancer
- if a variant has already been identified in the family, confirmatory testing for that specific variant can be offered to other affected relatives, potentially confirming their diagnosis of hereditary breast/ovarian cancer
- if a variant has been identified in the family, predictive testing for that specific variant can be offered to unaffected at-risk relatives, thereby clarifying their risk of developing cancer.
Sonic Genetics provides different panels of genes for testing for hereditary breast/ovarian cancer:
- BRCA1 and BRCA2 genes only (rebated testing only available for determining olaparib eligibility)
- Standard panel: BRCA1, BRCA2 and PALB2 genes only
- An expanded panel of 16 genes: ATM, BRCA1, BRCA2, BRIP1, CDH1, CHEK2, MLH1, MSH2, MSH6, PALB2, PMS2, PTEN, RAD51C, RAD51D, STK11, and TP53
Sonic Genetics also offers testing for a family’s specific mutation in any of the genes listed above.
Variants in these genes can potentially cause breast or ovarian cancer, or both, and a variety of others cancers. The requesting doctor can select the panel which meets the needs of the patient and the requestor’s experience. In particular, the expanded panel is only suitable for requestors familiar with the management considerations arising from identification of a variant in any of these genes.
The identification of a pathogenic variant in one of these genes in an affected person can explain the personal and family history of cancers. These variants can also provide prognostic information (which varies with different genes). Variants in the BRCA1 and BRCA2 genes can inform chemotherapy decisions as they identify cancers that are likely to respond to PARP inhibitors such as olaparib. The test result can also indicate the risk to the patient of subsequent cancers.
When testing an unaffected person, the identification of a pathogenic variant indicates a relatively high risk of developing cancer. There are surveillance and intervention strategies recommended for unaffected patients with pathogenic variants in the various genes tested. Depending on the clinical setting, the absence of the family’s variants may indicate that the patient is not at increased risk of developing cancer, despite the family’s history.
Please note that interpretation of the genetic test result may be dependent on the family history and other clinical and laboratory information.
Analysis of these genes can raise significant clinical, psychological, familial and financial issues that patients should address before consenting to the test. These considerations become more complex as more genes are included in a gene panel.
Sonic Genetics offers pre- and post-test genetic counselling for these tests with a certified genetic counsellor by phone or telemedicine. This counselling is available upon a doctor’s request at either no charge or for a fee depending on the context and test being considered; please contact us for details. There is no Medicare rebate for genetic counselling. Our genetic counselling is managed as a clinical service, with letters to the requesting doctor and patient summarising the outcome.
We recognise that genetic counselling may not be required in every situation, and that other genetic counselling services are available to patients and doctors. Pre-test genetic counselling is not mandated by Sonic Genetics for test requests from a specialist. We require an indication that informed written consent has been obtained prior to performing the test.
Download the Sonic Genetics consent form. Other appropriate consent forms are accepted.
Sequencing of the coding and exon/intron boundaries of the genes included in the panel. PMS2 coverage includes exons 1 - 10. Copy-number analysis is limited to the BRCA1 and BRCA2 genes only.
Gene variants of unknown significance are reported.
Requesting the test
These tests will only be accepted if requested by a specialist or consultant physician. General practitioners are encouraged to refer patients seeking testing to an appropriate specialist.
Please use our dedicated Hereditary Cancer request form for both rebated and non-rebated testing. Please indicate on the request form if genetic counselling is to be provided by Sonic Genetics. Note that pre-test genetic counselling for non-rebated testing is a chargeable service.
4 mL blood in EDTA (separate dedicated tube required). Specimens may be collected by the requesting practitioner or at any Sonic Healthcare pathology collection centre.
It is recommended that predictive testing be repeated on a second independently collected sample and in parallel with a positive control (sample from another relative confirmed to have the familial variant). These confirmatory tests are available at no extra cost.
We recommend that the patient or another adult check the labelling of request forms and sample tubes.
Please indicate whether the patient has a personal history of cancer, details of the family’s variant (if known), whether testing is being done to determine access to PARP inhibitors under the PBS, and whether the request meets the requirements for rebated testing.
Requests for testing for the family’s known variant must be accompanied by a copy of the laboratory report describing the mutation identified in a relative.
4-6 weeks from receipt of sample into the laboratory.
These panels of genes have Medicare rebates which, subject to the requirements of a Medicare descriptor being met, may cover all or part of the cost.
When testing a relative for the family’s mutation i.e. a test for a specific mutation in just one gene, there is a Medicare rebate for such testing of the BRCA1, BRCA2, CDH1, MLH1, MSH2, MSH6, PALB2, PMS2, PTEN, STK11, and TP53 genes only.
For non-rebated testing, the private fee is $400.
For details of the Medicare rebates available, please click here.
- Expanded testing for hereditary breast and ovarian cancer - Technical Bulletin
- Assessing the chance of a HBOC mutation (Manchester score sheet)
- Hereditary cancer request form
- Medicare rebates for breast cancer gene testing.
- Genetic counselling resources
- Cancer Institute of NSW (Fact Sheets, Guidelines etc).
- MJA article "Medicare-funded cancer genetic tests: a note of caution".