Unique Chemo Regimen is Extremely Effective in Certain Breast Cancers
A study led by Judith Hurley, M.D., associate professor of clinical medicine at the University of Miami Sylvester Comprehensive Cancer Center, showed that platinum-based chemotherapy combined with Herceptin is highly effective against HER2-positive, locally advanced breast cancer. The study is so significant that editors at the prestigious Journal of Clinical Oncology opted to publish the results early, online. Dr. Hurley has been a national leader in the study of locally advanced breast cancer for more than 15 years. “This is a natural progression of our research showing that platinum-based regimens can cure breast cancer,” said Hurley, who is also medical director of the oncology clinics at Jackson Memorial Hospital.
The five-year disease-free survival rate for patients with stage III locally advanced breast cancer is between 20 and 30 percent. But Dr. Hurley’s patients had an 85 percent survival rate at 43 months. “The fact of the matter is that seven relapsed but 41 did not,” said Hurley. “Considering these tumors were an average of 9 centimeters (3 ½ inches) and HER2 over-expressing, you would expect at four years that most of the patients would have relapsed.” The largest tumor in Dr. Hurley’s study was 35 centimeters – more than 13 inches.
Forty-eight patients were enrolled in this study. All had locally advanced breast cancer with tumors more than 5 cm in size and all tested positive for the presence of human epidermal growth factor receptor 2 (HER2). HER2 is a protein that occurs naturally in glandular cells like breast tissue. When it occurs in unusually high amounts it can fuel the proliferation of cancer. Each patient underwent three stages of therapy: a 12-week chemotherapy regimen of docetaxel, cisplatin and Herceptin to shrink the tumor; surgery to remove the remaining tumor; then a 12-week chemotherapy regimen of adriamycin and cyclophosphamide.
Every single patient responded to the therapy. Many showed visible tumor shrinkage within one day of treatment with cisplatin, docetaxel and herceptin chemotherapy.
Dr. Hurley began working with platinum-based chemotherapy in 1990 after she found more traditional regimens were not effective in her patient population. Across the United States, only about 6 percent of breast cancer patients present with locally advanced breast cancer – about 13,000 women a year. But it is the most common breast cancer diagnosis in many places outside the United States and nearly one in four of Dr. Hurley’s patients – 23 percent – have that diagnosis. The reason for this preponderance of locally advanced breast cancer in Miami is not known for certain, but Miami’s large minority population and high number of uninsured and underinsured patients are probably contributing factors. “I happened to be in the right place at the right time,” she said. “My research career started because there was a clinical problem that I didn’t know how to solve, so I set about trying to solve it.”
Hurley found three studies, one in bladder cancer and two in breast cancer, published in the late 1980s that all showed good results with platinum-based chemotherapy, so she began her own study at UM. Of the 75 patients enrolled, one in three had a complete pathologic response – elimination of the tumor from chemotherapy alone. Based on these promising results she has performed a set of nested studies evaluating platinum-based chemotherapy in the curative therapy of breast cancer. Subsequent studies have evaluated the addition of Taxotere and Herceptin to cisplatin and the modification of dosing schedule with even better results.
Publication of those studies caught the attention of Dennis J. Slamon, M.D., Ph.D., chief of the UCLA Oncology Center and the creator of Herceptin, who participated in the current study. He was sent tissue samples and voluntarily determined the HER2 status of each patient on the study. “This is the first study using Herceptin in the curative setting with long-term survival data,” said Hurley. Normally patients treated for HER2 positive tumors suffer a relapse very quickly – within 18 months. Those who do relapse have extremely poor prognoses. Of the 48 patients enrolled in this study, 41 are now beyond three years with no relapse.
Patients with breast cancer that over-expresses HER-2 can now enroll in a new trial at UM and JMH which speeds up the chemotherapy regimen. Studies have shown that “dose dense” chemotherapy, which is given every two weeks instead of every three weeks, may yield even better results. “Building on our previous research we hope to continue to improve the survival of women with HER2 over-expressing breast cancer,” said Hurley.
The current study is available online in the Journal of Clinical Oncology at this link: http://www.jco.org/cgi/content/abstract/JCO.2005.02.8886v1.
UM/Sylvester opened in 1992 to provide comprehensive cancer services and today serves as the hub for cancer-related research, diagnosis, and treatment at the University of Miami Leonard M. Miller School of Medicine. UM/Sylvester handles 1,400 inpatient admissions annually, performs 3,000 surgical procedures, and treats 3,000 new cancer patients. All UM/Sylvester physicians are on the faculty of the Miller School of Medicine, South Florida’s only academic medical center. In addition, UM/Sylvester physicians and scientists are engaged in 200 clinical trials and receive more than $31 million annually in research grants. UM/Sylvester at Deerfield Beach recently opened to better meet the needs of residents of Broward and Palm Beach counties. This 10,000-square-foot facility at I-95 and S.W. 10th Street offers appointments with physicians from six cancer specialties, complementary therapies from the Courtelis Center, and education and outreach events.