Growth Messages: Hormone and HER2/neu Status
Doctors want to know what’s motivating your cancer cells. By testing for three known cell “receptors” that are important to cell growth, doctors can reveal some of the ways your cancer cells proliferate (multiply). This can suggest powerful means to fight the disease.
Unfortunately, breast cancers in young women often lack some or all of these receptors, ruling out some treatment options. This page will help you learn about the different tests doctors perform so you can better understand your cancer, your treatment options and ways to manage the unique challenges many young women face.
Estrogen and progesterone: Doctors test cancer cells for receptors to the hormones estrogen and progesterone. Cells with estrogen receptor (ER) respond to estrogen and those with progesterone receptor (PR) respond to progesterone. These receptors often appear together — that is, “ER-positive” (or ER+) cancer cells can also be “PR-positive” (PR+).
ER+ and PR+ tumors use these specific hormones to grow. They generally grow more slowly, unless they are also Her2+. (see below) Learning that your cancer cells have these receptors can actually be good: doctors can then inhibit the cancer with drugs like tamoxifen or aromatase inhibitors that block the hormones.
HER2/neu (human epidermal growth factor receptor 2): This receptor also plays an important role in the system of signals involved in cell growth. It appears in extra amounts on the surface of some types of cancer cells, including breast and ovarian cancers. Pathologists examine cancer cells for HER2/neu overexpression using IHC (ImmunoHistoChemistry) or FISH (Fluorescence In Situ Hybridization) tests.
HER2/neu+ cancer is generally more aggressive than other breast cancers. However, learning that your cancer is HER2+ does suggest specific, targeted treatment options: The drugs herceptin and lapatinib can inhibit extra production of the protein. Other drugs now in clinical trials could offer additional options.
Triple Negative: Tumors in young women often lack all three receptors. In other words, they test ER-, PR- and HER2/neu-, making them “triple negative.” Unfortunately, this eliminates some effective treatment options and creates one of the unique challenges young women with breast cancer face. Triple-negative breast cancer can be more aggressive and more likely to recur.
If your cancer cells test triple negative, your doctor knows to turn to other treatment options. Just as they have for countless other young women, options exist to help fight your cancer. Chemotherapy is most often the treatment approach for triple-negative cancers. Recent research has focused on the use of PARP (Poly ASP ribose polymerase) inhibitors in the treatment of triple-negative breast cancer. Many other treatments now in clinical trials may begin to offer additional options.
Whatever your results, testing your receptor status will help your doctor devise the most appropriate treatment plan for you. Our challenges may be great, but together the women of YSC are strong enough to face them. Thousands of other young women have managed similar circumstances and are here to support you.
YSC also continues to advocate for more and better research on young women and cancer—especially on issues like targeted therapies that powerfully affect our population.