Appropriately Diagnosing and Classifying Breast Cancer
Joyce A. O’Shaughnessy, M.D., taps into her extensive experience to provide a brief overview of breast cancer presentation, diagnosis and classification.
PUBLISHED December 04, 2018
Joyce A. O’Shaughnessy, MD: Fortunately, most women with breast cancer present in the early stages, found either on their own self-examination or on a mammogram. Most women present with stage 1 or 2 or stage 3 breast cancer, all of which are curable. They don’t have any symptoms, but they maybe notice a mass or sometimes a rapidly growing breast cancer that can be a little uncomfortable. But there’s not much in the way of symptoms.
Unfortunately, metastatic breast cancer generally does present with symptoms. It comes to a woman’s attention because she has bone pain, for example, cough, or sometimes abdominal pain. Metastatic disease that has spread, usually to a vital organ or to a distant site, unfortunately does cause symptoms and those are what brings the breast cancer to attention.
There are 3 broad categories of breast cancer that we use to define the best treatment options for patients. The most common is the estrogen receptor–positive, hormone receptor–positive, HER2-negative [human epidermal growth factor receptor 2–negative] population. That’s about two-thirds of breast cancers. About 15% to 20% of cases are HER2-positive breast cancers, where the HER2 gene becomes amplified, there’s too much HER2, and HER2 is really driving that breast cancer. And lastly, there’s the triple-negative breast cancer, which does not have the estrogen receptor, the progesterone receptor, or HER2 positivity, but generally speaking, it’s a very fast-growing breast cancer. We utilize chemotherapy for that breast cancer. Those are the 3 broad categories of breast cancer that we have.