Decades ago, oncologists used uniform treatment approaches for most breast cancer patients. Today, medical advancements like genomic assays make it possible to treat each patient with the individual touch they deserve. Rocky Mountain Breast Specialists (RMBS) is at the forefront of providing this personalized breast cancer treatment.
What Are Genomic Assays?
Genomic assays are tests in which doctors use tumor samples to learn more about the type of cancer you have. Determining the cancer type helps oncologists decide which treatment methods will be most effective at eliminating the cancer with the least amount of stress on the patient’s body. Genomic assays are particularly effective with hormone-receptor positive forms of breast cancer.
Normal, healthy cells receive signals from the body about when to multiply and when to die and be replaced. Cancer cells ignore these signals. They multiply and continue to grow, often hiding from the body’s immune system. The more cells that are dividing at a single time, the more aggressive a cancer type is. Genomic assays tell providers detailed information about a cancer’s cell division. This information helps clinicians treat the cancer more effectively.
Genomic assays are not the same as genetic testing. Genetic testing looks at mutations in a person’s genes to determine whether they have an inherited risk of developing cancer in the future. Genetic testing is often used to determine a patient’s individual risk when they have a direct family member with cancer. Genetic testing uses blood, saliva, or other tissues to get results.
Genomic assay tests are performed using a small bit of an actual tumor. Genetic testing may help with treatment decisions, but genomic assays are the tests used to determine how aggressive a cancer is and to make critical care decisions.
There are three types of genomic assay tests:
- OncoType
- MammaPrint
- EndoPredict
Using Genomic Assays to Diagnose Breast Cancer
All types of genomic assays use a section of a preserved tumor. Providers often get parts of the tumor through a biopsy. A biopsy is a procedure to remove cells or tissues to be examined by a pathologist. Pathologists are physicians who study these tissues and cells in the body to help treatment teams make informed decisions. They are active members of your oncology team at RMBS. After your breast biopsy, it takes approximately two weeks for your provider to receive your genomic assay test results.
Along with your genomic assay test, a histological chemical stain may be used to help view the tumor sample under a microscope. The stain helps physicians view the structure of a tumor to understand the biology of a cancer.
The OncoType genomic assay test uses a 21 gene recurrence score. The score ranges from 0 to 100. A patient’s score tells the oncology team what a patient’s risk level is based on their cancer.
A score of 0-17 is low risk, 18-30 is intermediate risk, and above 30 is considered high risk.
The MammaPrint genomic assay test analyzes 70 genes related to breast cancer recurrence and generates a score based on the likelihood of cancer returning. That gives doctors the information they need to treat the disease effectively and, hopefully, prevent a second cancer. The MammaPrint is available exclusively for the examination of early-stage breast cancers. This test is an option for individuals with cancers that have spread to three or fewer lymph nodes and are:
- Hormone-receptor positive
- Hormone-receptor negative
- Invasive
- Less than 5 centimeters in size
- Stage 1 or 2
The EndoPredict genomic assay test examines the RNA expression associated with 12 genes to come up with a score that, combined with certain characteristics of a tumor, helps determine the chances of the disease returning within 10 years. As with other genomic assays, the scores help doctors make decisions related to treatment. If a score suggests a high risk of recurrence, physicians can consider adding hormone therapy to a patient’s treatment plan. If the patient has a low risk, a doctor may decide chemotherapy isn’t necessary.
