What Are the Prognosis and Survival Rates for Advanced Breast Cancer?
Breast cancer is the second most common cancer in women, after skin cancer, and it is the second leading cause of cancer death in women, after lung cancer.1 The prognosis, or forecast of the outcome of the disease, and survival rates are estimated by the stage of the disease.
Advanced breast cancer includes both locally advanced breast cancer and metastatic breast cancer, encompassing stages III and IV. While breast cancer that is caught in its earliest stages has very high survival rates, those survival rates decline when breast cancer is considered advanced.2
Prognosis and survival rates
Prognosis is unique to every individual with breast cancer. When looking at statistics, researchers look at large numbers of individuals. These numbers can be distressing. However, the statistics do not necessarily predict what will happen to anyone individual.
Survival rates are determined on the previous outcomes of people who survive a specific amount of time after diagnosis. In advanced breast cancer, as in other types of cancer, experts use “five-year survival rate” as a marker for prognosis.2
It is important to remember that many people live beyond this 5-year marker after diagnosis of breast cancer and these statistics are not predictive for any particular individual. In addition, to determine these rates, statisticians look at the past. The statistics do not consider how treatments are evolving and improving over time. The survival rates also are based on the initial diagnosis and do not apply to breast cancers that recur or spread after initial diagnosis.
Factors influencing prognosis
The prognosis and survival rate of breast cancer is dependent on several factors, including3,4:
- The stage of the breast cancer
- The type of breast cancer
- How fast the breast cancer is growing (proliferation rate)
- Whether the breast cancer is positive or negative for hormone receptors
- Whether the breast cancer is positive or negative for human epidermal growth factor receptor 2 (HER2)
- Whether the breast cancer has just been diagnosed or if it has recurred
- The age, menopausal status, and general health of the individual
Survival rates by stage
Survival rates of breast cancer are greatly influenced by the stage of the disease. In general, terms, when breast cancer is confined to the breast, it is considered localized. Sixty-two percent of all breast cancers are initially diagnosed at this stage.2
If the breast cancer has spread into surrounding tissues, including the lymph nodes under the arm or around the collarbone, it is considered regional. These may also be considered locally advanced breast cancers; 30 percent of all breast cancers are initially diagnosed at the regional stage. Metastatic breast cancer (also called stage IV) is characterized by cancer having spread (or metastasized) from the breast to other parts of the body. Approximately 6 percent of all breast cancers are initially diagnosed at this stage.2
- The 5-year relative survival rate for localized breast cancer is 98.8%.
- The 5-year relative survival rate for regional breast cancer is 85.5%.
- The 5-year relative survival rate for metastatic breast cancer is 27.4%.2
It is important to remember that these statistics do not consider the specifics for any individual, and 5-year survival rates are based on past data. The above numbers are currently based on data from 2009-2015, collected by the National Cancer Institute. These survival rates are also based on the initial diagnosis and do not include breast cancers that have recurred (breast cancer that has come back after treatment).2 Treatment continues to evolve for advanced breast cancer, and women are living longer with advanced breast cancer. One study found that women are living longer with metastatic breast cancer, including those diagnosed at younger ages (ages 15-49). While an estimated 40 percent of women currently living with metastatic breast cancer have had their disease for two years or less, another estimated 34 percent have lived for five years or more with MBC. The length of time that women are living with metastatic breast cancer is increasing, with 11 percent of women diagnosed with MBC during 2000-2004 less than 64 years old surviving 10 years or more.5,6