Breast cancer stages refer to the progression level of the disease, starting with Stage I, the least severe, and going up to Stage IV, the most severe. Breast cancer that reaches Stage IV remains incurable, but treatable. Typical statistics of survival rates and prognoses for cancer reflect averages of all types of breast cancer within a certain stage. Several factors affect the prognosis of Stage IV breast cancer.
Definition
"The Core Curriculum of Oncology Nursing" describes Stage IV breast cancer as cancer that spreads, or metastasizes, to another part of the body. Some cases of breast cancer go undiscovered until they reach Stage IV. Breast cancer that has been previously treated may also return in another part of the body. Common sites for breast cancer to spread to include the lungs, brain, bone, and liver.
Survival Trends
Imaginis.com reports that the overall five-year survival rate for Stage IV breast cancer reaches only 20 percent. These percentages vary depending on several factors. Because Stage IV breast cancer remains incurable, long-term survival becomes the goal of treatment.
Receptor Status
Often times hormones including estrogen and progesterone cause breast cancer to grow. Hormone receptor status becomes an important factor in Stage IV prognosis. These types of cancers are considered estrogen or progesterone positive, ER+/PR+. These types of cancer respond to treatments better than cancers that are considered ER-/PR-. Three-year survival of ER+/PR+ breast cancer reaches 97 percent whereas ER-/PR- breast cancer survival is 83 percent.
Histology
Histology describes that type of breast cancer cells found in a tumor. The histology becomes an important factor in Stage IV breast cancer prognosis because cancers vary in their aggressiveness. For instance tubular adenocarcinoma of the breast is one of the most survivable types of breast cancers. Inflammatory breast cancer is very aggressive and five-year survival rates for stage four reach only 11 percent, according to the National Cancer Institute.
Other Factors
Many other factors effect prognosis and survival rates of Stage IV breast cancer. These include but are not limited to the area in which the cancer has spread, size of the metastasized tumor, response to and tolerance of treatment, age, genetic history of breast cancer, and race.
References
- Imaginis: Staging and Survival of Breast Cancer
- National Cancer Institute: Seer Breast Cancer Statistics
- "Core Cirriculum for Oncology Nursing"; Itano, J. Ph.D., Taoka, K. MSN; 2005
