Studying Various Breast Cancer Treatments

Las Vegas—With numerous forms of breast cancer found in patients, physicians must use available information and tools to offer personalized treatment options, according to remarks presented during a session at the Fall Managed Care Forum titled Treatment of Primary and Advanced/Stage IV Breast Cancer: 2010. In 2009, there were an estimated 192,370 cases of invasive breast cancer and 62,280 in situ cases in the United States. That same year, 40,170 women in the United States died of breast cancer, the second leading cause of cancer death. During their lifetime, 1 in 8 women develop breast cancer and 1 in 30 die from the disease. When treating primary breast cancer, physicians should consider planning adjuvant therapy as well as prognostic markers, according to George Somlo, MD, director of breast oncology at the City of Hope Comprehensive Cancer Network. He said therapy depends on the stage of cancer, the tumor size, the number of axillary lymph nodes involved, the estrogen/progesterone receptor status, the histopathology (grade, mitotic index, and vascular invasion), and other molecular markers such as human epidermal growth factor receptor 2 (HER2). Dr. Somlo cited several trials that studied breast cancer treatments. A randomized trial of 30,000 women who took tamoxifen found that the drug was effective in reducing recurrence, death rate, and contralateral breast cancer. After 1 year, there was a 21% reduction in recurrence, a 12% reduction in death rate, and a 13% reduction in contralateral breast cancer. After 2 years, there was a 29% reduction in recurrence, a 17% reduction in death rate, and a 26% reduction in contralateral breast cancer. After 5 years, there was a 47% reduction in recurrence, a 26% reduction in death rate, and a 47% reduction in contralateral breast cancer In addition, a randomized, prospective, doubleblind trial of 4400 postmenopausal women with tumors not known to be estrogen receptor–negative determined that those patients who switch to exemestane after 2 to 3 years of adjuvant tamoxifen will result in modest improvement in breast cancer–free and overall survival. Exploratory analysis found that patients treated with exemestane following tamoxifen had smaller numbers of recurrences in bones at distant metastatic sites compared with patients treated only with tamoxifen. Dr. Somlo mentioned tools available to refine breast cancer prognosis and assess the benefits of the numerous treatment options include the TNM Classification of Malignant Tumors, cancer pathology, computer models, and molecular assays and arrays. He also suggested ongoing studies of those tools and their integration into clinical decision-making are crucial to improving therapies. Dr. Somlo also discussed various therapies recommended by the National Comprehensive Cancer Network to treat HER2-negative metastatic breast cancer. Complete remission is rare, and no randomized trials have proven survival benefit when continuing to take the drugs after maximum response. He also said healthcare professionals should assess the impact of side effects on quality of life and the risk of inducing resistance with continuing therapy.