"Since breast cancer is so common, and adjuvant drug therapy has already been found to be so effective, a way to make that treatment 31 percent more effective could potentially save thousands of lives per year in the United States alone," said Larry Norton, MD, Head of the Division of Solid Tumor Oncology at Memorial Sloan-Kettering Cancer Center, and senior author of the study.
A mathematical model called the Norton-Simon hypothesis formed the basis for the concept of dose density and another concept tested in this study, sequential therapy. The model, developed by Dr. Norton, and Richard Simon of the National Cancer Institute, was used to address the question: "Is it better to use a higher dose of a drug less often or a lower dose more frequently?" According to Dr. Norton, the answer depended upon the efficacy of the drugs and the pattern of growth of the disease, and could not be answered without a mathematical understanding of the underlying biology.
The study enrolled 2005 women with primary breast cancer that had spread to the lymph nodes, and with no other metastases. They were randomized post-operatively to one of four treatments. Two groups of patients were randomized to receive doxorubicin (A for Adriamycin), paclitaxel (T for Taxol), and cyclophosphamide (C for
Cytoxan) sequentially, i.e., one at a time, in two- or three-week c
Contact: Christine Hickey
Memorial Sloan-Kettering Cancer Center