Concurrent chemotamoxifen halves benefit of chemotherapy.(Brief Article)

2002 JUL 11 - (NewsRx.com & NewsRx.net) -- by Janis Kelly, senior medical writer - Results of a major, long-term study presented at the 38th Annual Meeting of the American Society of Clinical Oncology in Orlando, Florida, are expected to establish a new standard of care for postmenopausal women with breast cancer.

The North American Intergroup Trial 0100, reported by Kathy Albain, MD, showed that giving tamoxifen concurrently with chemotherapy dramatically reduced both disease-free survival and overall survival compared with delaying tamoxifen until after the completion of chemotherapy.

"Concurrent chemotamoxifen may result in suboptimal benefit from this or similar chemotherapy programs, potentially cutting efficacy by as much as 50%. The results of INT 0100 support a new practice standard of starting adjuvant tamoxifen after chemotherapy is completed," said lead investigator Albain, who is director of breast cancer research and codirector of the Breast Care Center at Loyola University's Cardinal Bernardin Cancer Center in Chicago, Illinois.

Although Albain advised physicians who have patients in the midst of a concurrent chemotherapy/tamoxifen regimen to "stay the course" ? which for most regimens is about 6 months ? she acknowledged that patients who opt to stop tamoxifen until they complete chemotherapy are likely running no major risk.

Optimal sequencing of chemotherapy and tamoxifen has been a contentious issue since in vitro studies suggested that tamoxifen, which freezes cells in the mitotic process, might render cell-cycle dependent anticancer drugs less effective by depriving them of the moving target they need.

This study aimed to settle that question by comparing three regimens. The investigators randomized 1477 postmenopausal women with hormone-receptor-positive breast cancer to 5 years ...