PARIS, France--Since 1991, breast cancer has been the most common diagnosis for which bone marrow transplants are performed. Therapy-related mortality has plunged to 6% or less, and the procedure's popularity has grown steadily to the point where more than a quarter of transplants for breast cancer are now done in women receiving adjuvant chemotherapy for stages II and III disease.
Although data from controlled, randomized trials are not yet available, results of a survey of 42 American transplant centers suggest the advantages of high-dose chemotherapy supported by transplant, said William P. Peters, MD, president, Michigan Cancer Foundation.
Dr. Peters' survey compared outcomes in 2,601 transplant recipients with published data on similar breast cancer populations that had been treated with conventional dose therapy.
Speaking at the Fifth International Congress on Anti-Cancer Chemotherapy, he reported that in 1,939 patients with metastatic breast cancer who received transplants, 5-year overall survival was roughly 30% in women with stage IV disease and nearly 60% in women with stage IIIB disease.
When the data were broken down by tumor responsiveness, median overall survival was 2.6 years for women with chemosensitive tumors, 1.87 years for partial responders, and 1.27 years for nonresponders.
Even among women with hormone-insensitive tumors, approximately 33% were alive after 3 years and 25% survived as long as 5 years. "Compared to our usual results in metastatic disease, these data are not too disappointing," Dr. Peters said.
In contrast, in a cohort of 91 patients with hormone-receptor-negative tumors who were treated with conventional therapy at M.D. Anderson, 3-year survival was 19%, and 5-year survival was 8%. Moreover, Dr. Peters said, 3-year survival was only 5% in 64 estrogen-receptor-negative patients identified in two published CALGB series, and only 8% in 39 receptor-negative patients previously reported in a SWOG series.