A Toolkit for Clinicians: Integrating Genomic Testing into Routine Breast Cancer Care
Genomic testing is becoming an important part of breast cancer diagnosis, treatment selection, inherited cancer risk assessment, and family care. Used well, it can help clinicians match patients with targeted therapies, identify clinically significant hereditary variants, and avoid treatments that are unlikely to provide benefit.
The value of testing depends on more than ordering a panel. Results must be connected to a clear clinical question, interpreted alongside pathology and imaging, and communicated in a way that patients and families can understand. A consistent workflow helps teams provide timely care while managing uncertainty, consent, privacy, and follow-up.
This practical toolkit is designed for breast surgeons, oncologists, pathologists, genetic counsellors, nurses, general practitioners, and allied health professionals. It supports a coordinated approach that can be adapted to local breast cancer pathways, laboratory arrangements, funding requirements, and governance policies.
Define The Clinical Purpose
Start by identifying why genomic testing is being considered. A tumour test may look for acquired changes that guide treatment, while a germline test assesses inherited variants that may affect the patient and relatives. These are different investigations, with different consent requirements, reporting processes, and implications.
The clinical question may relate to an early-stage tumour, metastatic disease, treatment resistance, or a suspected hereditary cancer syndrome. Relevant examples can include BRCA1, BRCA2, PALB2, and other hereditary breast cancer genes, as well as tumour alterations such as PIK3CA or ESR1 in appropriate disease settings. Testing should align with current evidence, nationally recognised guidance, and the availability of a treatment or clinical trial.
Before ordering, document the reason for testing, the specimen required, the expected turnaround time, and how the result could change management. This prevents broad testing from becoming a substitute for clinical judgement.
Build Testing Into The Care Pathway
Genomic assessment works best when it is built into routine multidisciplinary care rather than added after treatment decisions have already been made. At diagnosis, the breast team can review personal and family history, tumour subtype, age at diagnosis, treatment history, and the possibility of inherited risk.
Pathology and oncology services should agree on specimen handling, quality thresholds, test selection, and communication between the laboratory and treating team. Tissue availability can be limited, particularly after biopsy or previous treatment, so early coordination may prevent delays. Where a blood or saliva sample is required, clinicians should explain collection requirements and the possibility of a repeat sample.
Results need to arrive at a clinically useful point. A rapid result may be important when it could influence surgery, systemic therapy, trial eligibility, or referral to a hereditary cancer service. However, speed should not remove essential quality checks or patient-centred consent.
Interpret Results In Context
A genomic report is not a treatment plan. Clinicians should interpret the finding alongside hormone receptor status, HER2 status, tumour grade, stage, comorbidities, previous therapy, patient preferences, and the strength of evidence connecting the alteration with an intervention.
Reports commonly classify variants as pathogenic, likely pathogenic, uncertain significance, likely benign, or benign. A variant of uncertain significance should not be used to guide major treatment or family decisions. The report should also be checked for limitations, including low tumour content, insufficient coverage, technical constraints, and the possibility that a negative result does not exclude inherited risk.
A molecular tumour board or equivalent multidisciplinary forum can support complex cases. Discussion is particularly valuable when a result has several possible therapies, when evidence is emerging, or when a tumour finding may indicate a germline variant. Clear documentation should record the interpretation, the decision made, the responsible clinician, and the plan for review if evidence changes.
| Testing context | Main purpose | Common clinical question | Essential follow-up |
|---|---|---|---|
| Germline testing | Identify inherited cancer susceptibility | Could this result affect the patient’s care or relatives’ risk? | Genetic counselling, family communication, surveillance planning |
| Somatic tumour testing | Identify acquired tumour alterations | Is there a targeted treatment or trial relevant to this cancer? | Molecular review and treatment discussion |
| Tumour-first testing | Screen for findings that may warrant inherited testing | Does the tumour result suggest a possible germline variant? | Confirmatory germline testing where appropriate |
| Genomic profiling in advanced disease | Explore treatment resistance or new options | Has the tumour developed an actionable alteration? | Review evidence, eligibility, and goals of care |
| Negative or uninformative testing | Clarify what has not been established | Does the result rule out hereditary risk or treatment options? | Reassess family history, pathology, and future testing needs |
Make Consent And Data Governance Routine
Genomic consent should cover the purpose of testing, possible results, limitations, implications for relatives, storage of samples, data use, and the possibility of future reinterpretation. Patients may need time to consider whether they want information about inherited risk, particularly when the result could affect family relationships or life planning.
Clinicians should distinguish clinical testing from research participation. Research data may be coded, shared across institutions, or used for future studies under approved governance arrangements. A clear understanding of ethical data sharing helps teams explain privacy, access, consent, and community expectations without creating unnecessary alarm.
Record who provided consent, what was discussed, the laboratory used, and how results will be communicated. Confidentiality must be maintained, while systems should still support appropriate family notification and referral when an inherited finding has implications for relatives.
Support Capability And Equitable Access
Genomic medicine requires shared capability across metropolitan, regional, and rural services. Staff need practical education on test indications, family history collection, variant terminology, referral thresholds, and communicating uncertainty. The statistics education series can help clinicians strengthen their understanding of evidence, risk, and the interpretation of research findings.
Access should not depend on a patient’s confidence with medical language, location, income, cultural background, or ability to navigate multiple services. Use plain-language resources, interpreters, telehealth, and coordinated referrals where appropriate. Aboriginal and Torres Strait Islander patients and other communities may have specific concerns about genetic information, data custodianship, and research participation that should be addressed respectfully.
Health services can monitor turnaround times, test completion, result communication, referral rates, and patient experience. Reviewing these measures by geography and demographic group can reveal gaps that are invisible in overall performance data.
Practical Steps For Service Implementation
A local breast cancer service can introduce genomic testing through a small, clearly governed workflow and expand it as staff confidence grows. The following actions provide a practical starting point:
- Define testing criteria for inherited risk, early breast cancer, and advanced disease.
- Assign responsibility for consent, ordering, result review, patient communication, and family referral.
- Create a standard genomic testing template within the electronic medical record.
- Establish a multidisciplinary review process for uncertain or potentially actionable findings.
- Audit access, turnaround times, clinical decisions, and patient-reported understanding.
The workflow should include escalation pathways for urgent results, arrangements for genetic counselling, and a process for reviewing amended laboratory reports. Education should be continuous because testing technologies, drug approvals, clinical trials, and variant interpretations change over time.
A reliable system also gives patients a clear point of contact after testing. Written information should explain when the result is expected, who will discuss it, what a result may mean, and how patients can obtain support for themselves or their families.
Genomic testing becomes most valuable when it is integrated into compassionate, evidence-informed breast cancer care. Clinicians and health services can begin by mapping the current pathway, identifying delays or gaps, and agreeing on a shared standard for consent, interpretation, documentation, and follow-up. Use that baseline to build a service that translates genomic information into safer decisions, appropriate treatment, and better outcomes for patients and communities.
