Breast cancer is the most common malignancy found among women in the United States, excluding non-melanoma skin cancer, and is the leading cause of cancer death after lung cancer. According to The National Cancer Institute's 2008 estimates, more than 184,000 new cases of breast cancer and 41,000 breast cancer deaths are expected. The chance of developing invasive breast cancer during a woman's lifetime is approximately 1 in 8 (~12%), and the chance that breast cancer will be responsible for a woman's death is about 1 in 35 (~3%).
Over the past few decades, a significant progress has been made in battling the disease. 35 years ago, the 5 year mortality rate of women diagnosed with breast cancer was approx. 25%, while today it is no more than 10%. Improved new treatments were introduced, and from mastectomy (surgical removal of the breast) being the only accepted surgical option for breast cancer treatment, new breast conserving surgical procedures followed by radiation therapy are available. Moreover, the understanding of the disease has significantly improved, as scientists and physicians today know more about the different classes, subtypes and genetic risk factors of breast cancer, allowing them to match the most appropriate treatment.
That said, the decline in breast cancer mortality rate cannot be solely
attributed, not even by its larger part, to new advantageous treatments.
Rather, it is the increasing awareness of the public and progress made on the
cancer diagnostics arena that allow for early detection of breast cancer. A
patient diagnosed with cancer (whether breast cancer or other) is immediately
referred to staging tests, which are of major prognostic importance, as the
stage of the disease is closely correlated with patient's survival chances.
Moreover, staging will help the physician match the appropriate treatment for
When breast cancer patients become symptomatic, the disease reaches a stage at which the tumor is relatively large, and in most cases has already spread (metastasized) to lymph nodes and other organs. Therefore, detection of early stage breast cancer, so significantly increasing survival rates, can only be accomplished through effective screening. A brief description of several breast cancer screening and diagnosis methods is detailed in the next chapter: Breast Cancer - Imaging Methods.