Study results published today in the Journal of Clinical Oncology (JCO) may provide support for the early use of Taxotere (docetaxel) in the treatment of breast cancer. The study, conducted by the National Surgical Adjuvant Breast and Bowel Project (NSABP), showed improved clinical and pathological complete response rates in patients with operable breast cancer who were given Taxotere in addition to a standard anthracycline-based regimen prior to surgery compared to those patients who only received the pre-operative (neoadjuvant) anthracycline-based regimen. A clinical complete response is defined as the complete disappearance of all clinical signs of cancer and a pathological complete response indicates that no invasive cancer is present in the breast.
“While we’ve known for some time that neoadjuvant chemotherapy is beneficial for patients with more advanced breast cancer, this study demonstrates that patients with less advanced or operable breast cancer may also benefit from this approach,” said lead investigator Harry D. Bear, MD, Ph.D., professor and chairman, division of surgical oncology, Virginia Commonwealth University’s Medical College of Virginia and the Massey Cancer Center. “The addition of Taxotere to the pre-operative regimen significantly improved response rates. Research shows that improvement in response rates are predictive of longer survival for patients, which is why we are so encouraged by these results.”
In the large, Phase III study (NSABP Protocol B-27) patients were randomized to receive either four cycles of doxorubicin and cyclophosphamide (AC) followed by surgery (Group I) or four cycles of AC followed by four cycles of Taxotere, followed by surgery (Group II) or four cycles of AC followed by surgery and then four cycles of Taxotere (Group III). Among the most compelling findings was a 91 per cent increase in pathologic complete response rate among patients in Group II (AC followed by Taxotere), compared to those patients given just AC (26.1 percent vs. 13.7 per cent).
In addition to the statistically significant increase in pathologic complete response, patients in Group II (AC followed by T) also experienced a higher clinical complete response rate than patients given AC alone (63.6 per cent vs. 40.1 per cent) and a higher overall response rate or tumor shrinkage (90.7 per cent vs. 85.5 per cent). There was also an improvement in nodal status among patients given Taxotere as part of the neoadjuvant regimen compared to those given AC alone (58.2 per cent pathologically node-negative vs. 50.8 per cent).
In the study, 10.3 per cent of patients experienced a grade 4 toxicity while receiving AC, and 23.4 per cent of patients experienced a grade 4 toxicity while receiving Taxotere. The most common grade 4 event experienced by patients during treatment with Taxotere was febrile neutropenia (21.2 per cent).