Health Research

Jul 24 2007

New Study Confirms Link Between Breast Cancer and Hormone Therapy

A sharp decrease in breast cancer rates from 2003 to 2004 is linked to an even larger decrease in women's use of hormone therapy that began around 2000, according to a Kaiser Permanente study in the August issue of the Journal of the National Cancer Institute.

The study confirms the connection between breast cancer, hormone therapy and mammography screening over the past 25 years. It also provides even stronger evidence that recent declines in menopausal hormone therapy use are linked with lower incidence of breast cancer.

The study, conducted at Kaiser Permanente's Center for Health Research in Portland, Ore., reviewed the histories of 7,386 women diagnosed with invasive breast cancer and treated from 1980 through 2006. Researchers used Kaiser Permanente's unique, integrated care delivery and data systems – its tumor registry and clinical, pathology, and pharmacy data systems – to trace connections among breast cancer rates, mammography screening, hormone therapy use, and estrogen receptor status.

For more, read this news release.