New Drug Fights Type of Aggressive Breast Cancer
Lapatinib reduced tumor size in 80% of women with inflammatory malignancies
THURSDAY, Dec. 14, 2006 (HealthDay News) -- An experimental drug called lapatinib shows promise as a treatment for inflammatory breast cancer, according to a study presented Thursday at the San Antonio Breast Cancer Symposium.
Inflammatory breast cancer (IBC) is a rare (1 percent to 2 percent of all breast cancer cases), aggressive and often deadly form of breast cancer. Most breast cancers present as a lump, but symptoms of IBC include: redness; swelling; warmth in the breast; reddish, purple or bruised skin; or skin that has ridges and/or appears pitted like an orange.
Women with IBC may also have burning, aching or tenderness, increased breast size, and/or an inverted nipple. In many cases, IBC is diagnosed after the disease has spread to other areas of the body. Only 40 percent of IBC patients survive five years, according to background information in the article.
This multi-center phase 2 clinical trial began with 49 newly-diagnosed IBC patients. All were HER2 and/or EGFR-positive and had never been treated for their disease. About 25 percent of the patients had metastatic cancer.
For two weeks, the women received daily doses of lapatinib alone. That was followed by three months of daily lapatinib and weekly paclitaxel chemotherapy. Thirty-five of the women completed the drug trial and had surgery.
The study found that 27 of the 35 patients (80 percent) had a clinical response (defined as a 50 percent reduction in tumor size) to the lapatinib-chemotherapy treatment. One patient had disease progression during treatment.
The researchers also found that 25 percent to 30 percent of the patients responded in the first two weeks of the study when they were receiving only lapatinib, an epidermal growth factor receptor and HER2neu tyrosine kinase inhibitor. The drug blocks the activity of the HER2 protein and EGFR by binding to the part of the protein found inside breast cancer cells.
"For IBC patients, these results should be very encouraging because there's now more of a dedicated research effort for a type of breast cancer that has long been ignored and misunderstood," principal investigator Dr. Massimo Cristofanilli, associate professor, department of breast medical oncology, University of Texas M.D. Anderson Cancer Center, said in a prepared statement.
"With lapatinib, we finally have a drug on which to build effective therapy -- we just have to refine the most effective way to use it," Cristofanilli said.
The U.S. National Cancer Institute has more about inflammatory breast cancer.