New Regimen May Increase Chances of Breast Cancer Cure

The addition of the anticancer drug paclitaxel (Taxol) to standard chemotherapy may increase the chances of a cure for women with breast cancer.

A breast cancer trial headed by the Cancer and Leukemia Group B (CALGB) demonstrated that administering paclitaxel in addition to a standard chemotherapy regimen improved survival by 26% and reduced the risk of cancer recurrence by 22% when compared to the previous standard treatment regimen. These results were recently released by an independent monitoring committee and presented at the 34th annual meeting of the American Society of Clinical Oncology in Los Angeles.

"Dramatic" Results

"This represents the single most significant advance in the treatment of early-stage breast cancer in the past 20 years since the introduction of doxorubicin," said Richard L. Schilsky,MD, director, University of Chicago Cancer Research Center, professor of medicine, University of Chicago, and chairman, CALGB. "This new combination therapy has the potential to save tens of thousands of lives worldwide each year." There has not been a similar advance in adjuvant breast cancer therapy since the 1970s, when researchers discovered that postoperative combination chemotherapy substantially improved breast cancer survival compared to surgery alone.

"The results of this study are very dramatic. These data clearly demonstrate that we are substantially improving a woman’s chances for remaining free of her breast cancer by adding paclitaxel sequentially to the standard regimen of doxorubicin and cyclophosphamide," said Larry Norton, MD, head, Division of Solid Tumor Oncology, Memorial Sloan-Kettering Cancer Center. "Because it significantly improves survival, this regimen represents a new standard for patients with breast cancer."

Additional Follow-up Planned

"The significant increase in overall survival and reduction in recurrence at this early stage of the trial is extremely promising," he said. "Although the results are early, experience from other breast cancer adjuvant trials suggest that the early benefit will be maintained with continued follow-up." The CALGB will continue to monitor the progress of those enrolled in the trial for at least 10 years.

Of the 183,000 women newly diagnosed with breast cancer each year in the United States, approximately 75,500 are candidates for adjuvant therapy. "If we can decrease the risk of death among this large patient population by 26%, the implications will be staggering," said I. Craig Henderson, md, who was the principal investigator of the trial, which involved over 3,000 women.
"This regimen offers more women a chance for cure," said Dr. Norton.

 Largest Completed Study of Paclitaxel

This phase III, adjuvant trial, headed by the CALGB, was designed to compare doxorubicin plus cyclophosphamide to the same regimen followed by paclitaxel in women with breast cancer involving the lymph nodes under the arm. Sequential use was based on a mathematical analysis of breast cancer biology.

The trial involved more than 3,000 women and is the largest study ever completed with paclitaxel. Other cancer cooperative study groups involved in this study were the Eastern Cooperative Oncology Group, Southwest Oncology Group, and North Central Cancer Treatment Group, which are all sponsored and supported by the National Cancer Institute. In all, several hundred institutions participated in this study.

"These new data further the importance of screening and early breast cancer detection through consistent self-examination by all adult women. The more women we diagnose early, the more women will benefit from this important new treatment advance," said Dr. Henderson.