My Breast Cancer has recurred. How does this change my treatment choices, and are new targeted therapies using...

I'm so sorry to hear that your breast cancer has recurred. Recurrent or metastatic breast cancer certainly brings new challenges, but there are also additional treatment options that may be recommended based on the specific characteristics of the cancer.

For recurrent breast cancer, biomarker testing is extremely important to help guide the most appropriate therapies. The main biomarkers looked at are:

• Estrogen receptor (ER) and progesterone receptor (PR) status
• HER2 status
• Other molecular markers like PD-L1

According to the NCCN Guidelines, the choice of therapy hinges heavily on the biomarker status:

For ER/PR positive, HER2 negative cancers:

• Hormone therapies like aromatase inhibitors, fulvestrant, etc. remain a backbone of treatment
• Adding a CDK4/6 inhibitor like palbociclib is a newer targeted option

For HER2 positive cancers:

• Anti-HER2 therapies like trastuzumab, pertuzumab, T-DM1 are highly effective
• Novel antibody-drug conjugates like trastuzumab deruxtecan are the latest addition

For triple negative breast cancers:

• Chemotherapy is still commonly used
• For PD-L1 positive tumors, immunotherapy with atezolizumab is an option

So in summary, biomarker re-testing is crucial for recurrent disease, as this can open up new targeted therapy options beyond standard chemotherapy. I'd recommend discussing the biomarker results in detail with your oncologist to understand the most appropriate treatments for your specific situation.