Breast cancer is the most common cancer occurring among women and accounts for 30% of all cancers diagnosed in women. In the year 2000, invasive breast cancer was diagnosed in an estimated 182,800 women in the United States. Last year, 40,800 women died with breast cancer. More importantly, in situ (early) breast cancer was diagnosed in 42,600 cases. In Texas, an estimated 10,785 cases of invasive breast cancer were seen. The incidence rate for breast cancer in Texas varies among the various racial groups. Anglo American women have the highest incidence at 107 cases per 100,000 women, while Hispanic women have the lowest incidence at 69 cases per 100,000. For African American women, the incidence is 96 per 100,000; however, they have the highest mortality rate: 33 per 100,000 compared with the lowest mortality of 17 per 100,000 among Hispanic women.
Good news can be found in recent breast cancer statistics. The mortality rate from breast cancer has decreased substantially over the last decade at a rate of 1.8% per year. The incidence of in situ breast cancer has risen dramatically with the increasing use of screening mammography. The proportion of in situ breast cancer has increased from 3.6% in 1983 to 18% of all cases in 1999. Discovery of in situ breast cancer gives these women the best chance of cure with the greatest variety of therapeutic options. According to data from the Surveillance, Epidemiology, and End Results (SEER) program, more than 60% of patients in whom invasive breast cancer has been diagnosed have negative nodes. The 5-year relative survival rate for node-negative breast cancer is 96% compared with 75% for node-positive disease. These data reflect the success of screening mammography in identifying the earliest and most curable stages of breast cancer.
The increasing use of screening mammography has resulted in many benefits for women who will be diagnosed with breast cancer. The patient has the opportunity to undergo minimally invasive procedures to treat the tumor in the breast and to stage the axilla. Death rates from breast cancer have begun to decline for the first time in decades. We are seeing also a shift to earlier stages of disease.
While much interest has been shown in new techniques for breast screening (eg, magnetic resonance imaging, nuclear medicine sestimibi scans, and ultrasound), mammography remains the gold standard for screening. Randomized trials have proved that mammography reduces mortality from breast cancer. Despite the known benefits of breast cancer screening, its use is not optimal, particularly among the older population and the uninsured. In 1998, only 66% of Medicare-age women in Texas reported having had a mammogram in the past year.
Studies show that the physician remains the catalyst for most patients to undergo regular breast screening. When the physician actively promotes breast cancer screening, risk assessment, and prevention, the patient is more likely to follow through. The rewards are great when a small curable cancer is detected and treated early, with minimal disfigurement and morbidity.