Table A1.

Potential Discussion Points on the Use of Biomarkers to Guide Therapy Decisions for Patients With Early-Stage Invasive Breast Cancer

Key Point	Action
Explain the importance of determining the biologic characteristics of breast cancer.	Patients should understand that the most common biologic tests are those for ER, PgR, and HER2 and that testing for these markers is important to select an appropriate treatment. Patients should understand that assay validity and clinical validity of a biomarker are important steps in test development but that, by themselves, they are insufficient to guide treatment decisions outside of a clinical trial. The patient should be aware of the balance between benefit and harm and the importance of a biomarker showing clinical utility before being used in routine care. Patients and clinicians should understand that a wide range of biomarker tests are technically possible. In addition to ER, PgR, and HER2, only Oncotype DX, EndoPredict, Prosigna, Breast Cancer Index, and uPA/PAI-1 have demonstrated clinical utility for early-stage invasive breast cancer.
Explain the importance of ER, PgR, HER2, Oncotype DX, EndoPredict, Prosigna, Breast Cancer Index, or uPA/PAI-1 testing.	Patients should understand that in addition to ER, PgR, and HER2, Oncotype DX, EndoPredict, Prosigna, Breast Cancer Index, or uPA/PAI-1 status determines whether their prognosis is sufficiently good that chemotherapy might not be recommended.
Explain the types of tests used to determine ER, PgR, HER2, Oncotype DX, EndoPredict, Prosigna, Breast Cancer Index, or uPA/PAI-1 status.	Patients should understand that different testing methods are used to detect ER, PgR, HER2, Oncotype DX, EndoPredict, Prosigna, Breast Cancer Index, or uPA/PAI-1 status, which include evaluation of protein overexpression or the presence of genetic alterations.
Explain the interpretation of the ER, PgR, HER2, Oncotype DX, EndoPredict, Prosigna, Breast Cancer Index, or uPA/PAI-1 test results.	Patients should understand that although most test results are definitively positive or negative, there are equivocal results that require additional testing with an alternative test or the same or alternative test on a different portion of the same specimen (different block). Sometimes, the oncologist or pathologist may recommend additional testing with a different type of tumor specimen (eg, surgical excision v core biopsy), if available. Unfortunately, some results remain indeterminate or inconsistent with other histopathologic findings. In such cases, a final treatment decision to consider treatment with ER-, PgR-, or HER2-targeted therapy or therapy guided by Oncotype DX, EndoPredict, Prosigna, Breast Cancer Index, or uPA/PAI-1 should be made after consultation between the pathologist and oncologist and a discussion with the patient.
Explain that ER, PgR, HER2, and Oncotype DX, EndoPredict, Prosigna, Breast Cancer Index, or uPA/PAI-1 testing guidelines exist.	Guidelines are in place for testing biomarkers on tumor specimens. Although several tests are now recommended in the guidelines, only one needs to be used to guide therapy for an individual patient. Although the tests are similar in nature, they are not identical, and two tests on the same tissue may give different results. If two or more tests are applied to the same tissue, data do not exist on how to reconcile which test is superior or which should be used to guide treatment decisions. Patients may be referred to the ASCO Web sites for additional patient-focused information.

NOTE. Adapted with permission.³ During discussion about the use of biomarkers to guide therapy decisions, establish how the patient prefers to receive information, the patient’s perceptions of the diagnosis, and tumor factors that might influence decision making; educate the patient (and family members or caregivers) about the results of tests and how they are used to develop a treatment plan tailored to the biology of the cancer; and use easily understood language (at an educational level that the patient can understand) to communicate clearly.

Abbreviations: ER, estrogen receptor; HER2, human epidermal growth factor receptor 2; PAI-1, plasminogen activator inhibitor type 1; PgR, progesterone receptor; uPA, urokinase plasminogen activator.