Breast Cancer Basics: Chemotherapy and HER-2 Directed Drugs Used Before (“Neoadjuvant”) or After Surgery (“Adjuvant”)

Dr. Brian Lawenda introduces the most commonly used chemotherapy and HER-2 targeted drug therapies for patients with breast cancer (adjuvant and neoadjuvant treatment). He also briefly discusses the use of genomic assays (OncoType DX, MammaPrint) to assess your risk of recurrence with endocrine therapy alone versus endocrine therapy plus chemotherapy.

Breast Cancer Gene Expression Tests

If you have a stage 1-2 hormone receptor positive breast cancer, you may be eligible to have one of these assays done on your breast cancer tissue (in the lab) to determine whether you will you only need endocrine therapy-alone versus endocrine therapy plus chemotherapy. These assays look at your cancer’s genetics to predict if they are more or less likely to recur after surgery.
  • The Oncotype DX test analyzes the activity of 21 genes and then calculates a recurrence score number between 0 and 100; the higher the score, the greater the risk of recurrence of an invasive breast cancer.

  • The MammaPrint test analyzes 70 genes to see how active they are and then calculates either a high-risk or a low-risk recurrence score (the only one these three assays to be endorsed by the American Society for Clinical Oncology for the use in patients with 1-3 positive lymph nodes).

  • The Prosigna Breast Cancer Prognostic Gene Signature Assay analyzes the activity of 58 genes and calculates a risk of recurrence score (low, intermediate, or high).