SAN FRANCISCOMature survival analyses from the North American Breast Intergroup Trial (INT-0100; SWOG-8814) confirm that chemotherapy plus tamoxifen(Drug information on tamoxifen) (Nolvadex) produces better overall and disease-free survival than tamoxifen alone in postmenopausal women with node-positive, receptor-positive breast cancer.
Kathy S. Albain, MD, professor of medicine, Cardinal Bernardin Cancer Center of Loyola University Medical Center, Maywood, Illinois, presented the updated results at the 37th Annual Meeting of the American Society of Clinical Oncology (ASCO abstract 94).
"The overall survival curves do not diverge in favor of cyclophosphamide(Drug information on cyclophosphamide), doxorubicin(Drug information on doxorubicin) [Adriamycin], 5-fluorouracil, and tamoxifen (CAFT) until after year 4, but the advantage persists after that," Dr. Albain said. "The CAFT advantage also persists after adjustment for all of the significant prognostic factors."
The objectives of INT-0100 were to determine (1) if CAFT was superior to the 1988 standard of tamoxifen alone in postmenopausal women with node-positive, receptor-positive disease; and (2) if CAF followed by tamoxifen was better than concurrent CAFT. Dr. Albain reported final data on the CAFT vs tamoxifen comparison. She said that data on the concurrent vs sequential comparison are not yet mature.
The trial enrolled 1,477 eligible postmenopausal women with estrogen-receptor (ER)-positive, node-positive breast cancer. Patients were randomized to tamoxifen alone (n = 361), to CAF followed by tamoxifen (n = 566), or to concurrent CAF plus tamoxifen (n = 550).
Tamoxifen was given for 5 years, and CAF was given at standard doses for six cycles using oral cyclophosphamide for 14 days and doxorubicin and 5-FU on days 1 and 8. Radiotherapy was given either at the start or after the completion of CAF, or at the start of tamoxifen alone.
The main CAFT vs tamoxifen comparison met early reporting criteria for disease-free survival in 1996. A disease-free survival advantage for CAFT at 4 years was reported at the 1997 ASCO annual meeting. Median follow-up is now 7.3 years.