I am 48 with breast cancer. Is genome testing needed?

Question

Hello doctor,

I am a 48-year-old woman who was recently diagnosed with breast cancer. My oncologist suggested undergoing cancer genome testing to identify targeted therapies. Currently, I have been prescribed Mesalamine (aminosalicylate drug class) in the past for another condition, which provided only partial relief of symptoms.

Please tell me,

What does this genome testing actually show?
Does it mean that my children are at risk, or is it only related to the tumor itself?
Will insurance cover such testing?
How significantly does it change treatment decisions compared to standard chemotherapy?

Kindly help.

Answer 1

Hello,

Welcome to icliniq.com.

I have read your query and can understand your concern.

So let me break this down because it is a common confusion. Cancer genome testing usually refers to analyzing the tumor tissue itself, not your inherited genes. It looks for mutations in the cancer cells that might be driving growth, such as HER2 (human epidermal growth factor receptor 2), PIK3CA (phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha), and BRCA (Breast cancer gene – tumor mutation, not germline). This helps oncologists decide if a targeted drug or immunotherapy can work better than just standard chemotherapy.

Now, this is different from germline genetic testing (such as a BRCA blood test), which tells whether you carry a hereditary risk that can be passed to children. Tumor profiling alone does not mean your children are at risk. If your oncologist suspects hereditary cancer, they would specifically order germline testing.

I would suggest the following investigations be done:

Tumor molecular profiling (next-generation sequencing, HER2, estrogen receptor/progesterone receptor [ER/PR], PD-L1, depending on the type).

If the family history is strong (early cancers, multiple relatives), a germline genetic test such as BRCA (DNA Repair Gene—germline test) is recommended.
Routine staging scans and blood work.

I would recommend the following treatment plan:

The result of tumor testing may open doors for targeted therapy or immunotherapy. Examples include Trastuzumab (Monoclonal antibody – anti-HER2) if HER2 positive, CDK4/6 Inhibitors (Cyclin-dependent kinase inhibitors – targeted therapy), or PARP Inhibitors (Poly ADP-ribose polymerase inhibitors – targeted therapy) if BRCA mutation is present.

If no actionable mutation is found, then standard chemotherapy and/or hormone therapy remains the backbone of treatment.

Insurance coverage is variable. In India, most policies do not cover advanced genomic tests, though some private ones may partially cover. Abroad, certain insurance companies may cover it. You will need to check with your insurer directly.

In practice, the test changes treatment decisions in a subset of patients, not in all cases. However, for those who qualify, it can make a significant difference.

I would suggest the following preventive measures:

Maintain a healthy diet, regular physical activity, and a stable body weight.
Family members should only undergo genetic counseling or testing if there is a strong suspicion of hereditary cancer.
Follow regular breast check-ups and screening as per the oncologist’s advice.

I hope this helps.

Thank you.