As we come to the end of the year, many people are becoming more and more health conscious, focused on looking forward to 2016 and making resolutions to exercise more, eat healthier and get more rest. For those living with breast cancer, their health-related resolutions often focus on educating themselves about the disease so they can actively manage their cancer journey. For the approximately 175,000 US women living with the most advanced stage of breast cancer, however, there is very little information shared or resources available to support their disease journey. As you make your plans and resolutions for 2016, we encourage you to learn more about the advanced stage of breast cancer known as metastatic breast cancer (MBC).
MBC is referred to as Stage IV breast cancer and is a chronic, progressive from of the disease where the cancer has spread (metastasized) beyond the breast to other organs such as the lungs or bones. It is diagnosed through biopsy, in combination with imaging test, in order to determine where in the body it has spread. A woman can develop MBC if her early-stage breast cancer spreads, or she may be told she has Stage IV upon initial diagnosis. In fact, 6-10 percent of new breast cancer cases are diagnosed initially as Stage IV or metastatic, according to MBCN. Because the experience of living with MBC is so different from that of an early stage breast cancer diagnosis due to the chronic nature of the disease, education, support, and community awareness are critical to help those going through their journey.
Breast cancer can be hormone driven – and the progression of MBC can be directly related to the types of hormones and how they communicate within the tumor tissue – so it is extremely important for women diagnosed with MBC to learn if their MBC is hormone driven or not. This is often referred to as knowing your tumor’s hormone receptor status. This information will aid your medical team to identify appropriate treatment options and together you can select the best course of treatment to manage your MBC journey.
What Role Do Hormones Play in MBC?
The most common classifications for metastatic breast cancer types are hormone receptor-positive, HER2 positive, or triple negative.
Hormone receptors can be found throughout breast cancer cells. When you are first diagnosed with MBC, your doctor will run tests to confirm if the tumor is hormone receptor positive or negative. The most common types of hormone receptors are estrogen and progesterone receptors. If the test reveals positive results for either receptor type the disease is classified as hormone receptor positive. If neither is determined to be positive then the disease is classified as hormone receptor negative.
While not defined as a hormone, HER2 status is also often used as another type of classification for metastatic breast cancer cells. MBC patients are tested for HER2 (human epidermal growth factor receptor 2), a gene that can also have an impact on the growth of breast cancer tumors. In a healthy cell, the HER2 gene functions normally and contains a normal amount of HER2 receptors, which helps control the growth of healthy breast cells. When the HER2 gene does not function properly, this results in too many HER2 receptors, which causes the cancer cell to divide and grow more rapidly. This is called HER2 positive MBC.
Some metastatic breast cancer cells are neither estrogen, progesterone nor HER2 positive, so they are referred to as triple negative metastatic breast cancer cells. For these women the cause of their tumor growth is not hormone or HER2 related.
How Does Hormone Status Affect Treatment?
Knowing your tumor’s hormone receptor status can help you work with your doctors to identify the best treatment option for your specific type of MBC to help delay or stop the growth of the tumor. Those with hormone receptor positive tumors may have choices among the available hormone therapies. The aim of therapy is to reduce the amount of estrogen, block the estrogen receptor and/or work to destroy the estrogen receptor.
If your tumor is classified as HER2 positive or triple negative, your doctor will recommend a different type of treatment (eg, chemotherapy, radiation) specific to your type of metastatic breast cancer.
Because different hormones can impact cancer tumors in many ways treatment will require various approaches to best manage the disease. Knowing your tumor’s hormone receptor status is critical to determining a plan of action that best fits each individual. Knowing what drives tumor growth allows women living with MBC to actively manage their care and openly discuss the best course of action with their medical team.
A metastatic breast cancer diagnosis can be overwhelming and leave a patient and their loved ones with many unanswered questions, including what is MBC?, what do I need to know about my diagnosis?, how do I figure out what doctors I should be seeing to manage my care?, what side effects can I expect?
Reviewed August 11, 2015
by Michele Blacksberg RN
Edited by Jody Smith