HER2+ Early Stage Breast Cancer


Between taking care of your family, working and living life, you may feel it’s impossible to add anything else to your plate, let alone breast cancer. Where do you begin? In your case, learning as much as you can about your HER2+ early-stage breast cancer diagnosis and its treatment options is an excellent starting point. As you make your plan to move forward, surround yourself with a skilled medical team, a solid support system and trusted resources. The more you know, the more comfortable you’ll be making important decisions and being your own best advocate. And remember, you are not in this alone.

The Big Picture

To better understand your unique diagnosis, it may help to have a basic understanding of cancer. Cells typically divide in an orderly fashion. When they are worn out or damaged, they die, and new cells replace them. Cancer develops when genes begin to change, or mutate, within the structure of normal cells. If you have HER2+ breast cancer, one of the cellular changes that has occurred is the presence of too much human epidermal growth factor receptor-2 (HER2). These cells – now called cancer cells – grow and push against normal cells. Sometimes they form tumors.

Your doctor will characterize your breast cancer by looking at specific protein receptors evaluated on your breast biopsy tissue. The three most important receptors at this time are known as estrogen and progesterone receptors (ER and PR) and HER2. In your case, too much of the HER2 protein or extra copies of the HER2 gene were found, and the cells are growing and dividing in an uncontrolled way. That’s why it’s called HER2 positive (HER2+). The stage of your breast cancer is an important step. It is based upon the estimated size of the tumor in your breast, and an assessment of whether it appears to have spread to lymph nodes in your underarm or to other organs of your body. The tumor grade is also important when determining stage. The grade addresses the microscopic appearance of your cancer cells.

Understanding Your Treatment Plan

A notable aspect of early-stage HER2+ treatment is that it’s often needed for longer than you probably expect. It’s good to know that ahead of time, and it’s important to understand why. This prolonged therapy can be extremely effective.

Advances in targeted therapy for HER2+ breast cancer have improved survival rates dramatically. These advances require a commitment to prolonged treatment after surgery (called adjuvant and extended adjuvant therapy). Adjuvant therapy is done immediately post-surgery, while extended adjuvant therapy is a newer safeguard doctors may use later to ensure a further reduction in the risk of the tumor(s) recurring.

Often, treatment is also delivered before surgery (neoadjuvant therapy). If your cancer is hormone receptor positive in addition to being HER2+, you may also receive endocrine/hormone therapy for a number of years, usually in pill form.

These treatments are necessary and may reduce the risk of a recurrence. Accepting and even embracing your treatment schedule is just one way to be an active participant in your own care.

To guide your treatment plan, your doctor will consider stage, tumor markers (HER2, ER, PR), test results and overall health. These pages will provide information on each of the following:

  • Surgery – removal of cancer
  • Neoadjuvant – drug therapy or radiation therapy before surgery
  • Adjuvant – drug therapy or radiation therapy after surgery
  • Extended adjuvant – drug therapy after adjuvant therapy

As you read on, make a list of questions for your health care team, and continue to ask questions throughout your treatment. Being informed will make you a better partner in your treatment plan.

Breaking Down Genetics & Genomics

Genetics and genomics just sound complicated, right? They don’t have to be. The following may help you understand what they are and why your doctor used them to determine your diagnosis and decide how aggressively to approach treatment. As always, if anything isn’t clear or if you have more questions, ask your doctor for more information.

Tumor genomic testing is done to identify specific genetic mutations within the tumor, which may help determine if there are specific or targeted treatments available.

HER2+ breast cancer is an example of a genetic mutation within a tumor that results in over-production of the HER2 growth factor. Biopsy material revealing an invasive breast cancer is typically checked for expression of the HER2 biomarker because this information is important in planning treatment. It is routine to test tumors for ER, PR and HER2 expressions.

When categorizing genetic mutations, the two main types are acquired (genetic damage that occurs during a person’s lifetime) and germline (a genetic mutation that comes from the sperm or egg of the parents that is passed on to the child after conception). Most cancers are caused by acquired mutations. Germline mutations are less common, and genetic testing is typically done to detect these mutations to determine future cancer risk, especially if there is a history of certain cancers in the family. However, inheriting a germline mutation doesn’t mean a person will automatically develop cancer; it only means the risk is increased.

Germline genetics and genomics are not the same thing. Germline genetics is the study of genes and the passing of genetic information and traits from parents to offspring (heredity). Tumor genomics refer to the study of the genes and DNA within a person‘s tumor. Germline genetic testing may be performed before or after someone is diagnosed with cancer, to determine if a cancer-causing gene was inherited.

Mutations are common, and they don’t automatically cause cancer. But when the mutation causes cells to produce many abnormal genes or proteins, it can negatively affect the body by growing uncontrollably, interrupting normal body function and becoming cancerous.