SAN ANTONIO--The risk-to-benefit ratio for the use of adjuvant tam-oxifen therapy should be considered "outside of the narrow confines of survival or death from metastatic breast cancer," Monica Morrow, MD, said at the tamoxifen(Drug information on tamoxifen) roundtable.
For women with node-positive breast cancer, "the overwhelming force of mortality is always the breast cancer," but in women with smaller, node-negative breast cancers, other causes of mortality, eg, cardiovascular disease, complications of osteoporosis, and other cancers, are "a bigger issue," she said.
Dr. Morrow, director of the Comprehensive Breast Program at Northwestern University Medical School, cited data suggesting that, besides prevention of breast cancer recurrence, tamoxifen has additional benefits that might impact on overall survival.
"Namely, it can lower cholesterol levels and reduce hospital admissions for cardiovascular disease, as demonstrated in the Stockholm trial," she said, "and, as shown in the Scottish studies, even in older women, tamoxifen may reduce mortality from cardiovascular disease."
On the other hand, Dr. Morrow noted, the recent overview analysis of adjuvant tamoxifen from the Early Breast Cancer Trialists' Collaborative Group failed to demonstrate a reduction in non-breast cancer mortality with use of tamoxifen. I. Craig Henderson, MD, of the University of California, San Francisco, said he was "a little disconcerted" with the overview analysis results, and he remains unconvinced that the current analysis provides the final word on the subject.
He pointed out that the contributions of various trials to the overview have not been analyzed. "For example," he said, "the effect on cardiovascular and non-breast cancer mortality, which was rather striking at the last overview analysis, may be less so now because of the inclusion of many more trials with shorter follow-up."
V. Craig Jordan, PhD, DSc, of Northwestern University, who chaired the tamoxifen roundtable, agreed with Dr. Henderson. He stated that patients in many of the trials in the metaanalysis have not necessarily used tamoxifen for 5 years, whereas the data on hormone replacement therapy in postmenopausal women suggest that "longer is better in regard to maintaining protection against cardiovascular disease."