NEW YORK (Reuters Health) Jan 15 – For women at high risk of developing breast cancer, chemoprevention therapy with tamoxifen prolongs average survival, particularly among the youngest women and those with the highest risk.
"The effectiveness of tamoxifen in preventing breast cancer increases with risk of the population," Dr. Victor R. Grann, from Columbia University, New York City, told Reuters Health.
Therefore, women with atypical hyperplasia, increased Gail index, lobular carcinoma-in-situ, or a family history of breast cancer have an increased benefit in survival and quality-adjusted survival from tamoxifen. Based on increased survival and quality-adjusted survival, tamoxifen is both cost-effective and cost-saving, Dr. Grann said.
Dr. Grann and colleagues constructed a decision model using a hypothetical cohort of women at very high risk of breast cancer, including a subgroup with atypical hyperplasia, according to their report in the Journal of Clinical Oncology for January 1.
The researchers drew their data from the Breast Cancer Prevention Trial, the Surveillance, Epidemiology, and End-Results program, time trade-off preference ratings, the Group Health Cooperative of Puget Sound, and the US Health Care Financing Administration.
Their model predicted that for women beginning tamoxifen at 35 years of age, survival is extended by 70 days. For women who begin tamoxifen treatment at 50 years of age, survival is prolonged by 42 days. And for women who start tamoxifen therapy at 60 years of age, survival is lengthened by 27 days.
Survival was extended even longer among women with atypical hyperplasia who started tamoxifen at 35, 50 and 60 years of age (202 days, 89 days, and 45 days, respectively). Tamoxifen also prolonged quality-adjusted survival for these women by 158, 80, and 50 days, respectively.
The greatest survival was seen in the younger highest-risk women for whom tamoxifen was cost-effective and cost-saving with and without adjusting for quality of life, Dr. Grann's team found.
"Tamoxifen is the first chemoprevention medicine," Dr. Grann pointed out. He predicts "it is going to bring in a whole class of drugs that may prevent cancer so that you are not screening for actual cancers but are preventing cancers before they develop."
"Chemoprevention is a new strategy to conquer disease," Drs. V. Craig Jordan and Monica Morrow, from Northwestern University Medical School, Chicago, comment in a journal editorial.
"The new idea has again created uncertainty, but with enhanced cost-effectiveness and the resolution of troublesome side effects, we predict that a momentum will build so that the innovation will enhance the prospects of a breast cancer-free life."
J Clin Oncol 2002;20:1-3,9-16.