More in the Decline of Breast Cancer Incidence and Hormone Therapy Debate

By: Red Hot Mamas

Published: May 26, 2010

Written by Menopause Minute® Editors

We still don’t know what the reasoning is behind the 7% decline of breast cancer incidence between 2002 and 2003. Can it be attributed to the rapid decline of hormone therapy use after the Women’s Health Initaitive (WHI) results were released? Researchers are still rolling around the question.

During the December 6-9, 2009 Frontiers in Cancer Prevention Research Conference (hosted by the American Association for Cancer Research, or AACR), the debate was readdressed. A reevaluation of post-WHI data, by Brian Sprague, Ph.D. (University of Wisconsin), assesses other potential causes into account.

Sprague’s investigation definitely linked only 3% of the decline in breast cancer incidence due to the cessation of hormone therapy use after the WHI results were released.  Sprague explains in a recent AACR press release, “We found that the change in hormone therapy use only accounted for a decline of about 3 percent, so there’s another 4 percent that is being caused by something we do not yet know.”

The fact that only a small part of the decline can be directly attributed to hormone therapy use is a noteworthy result. It opens up additional debates about how we view hormone therapy use when treating menopause symptoms. Additional studies will open more doors and eventually determine other potential sources to attribute for the remaining decline in breast cancer incidence. Until then, these are the key facts:

  • Many women stopped using hormone therapy after WHI results were released
  • Women experienced a steep decline in breast cancer after WHI results were released
  • Only part of the decline in breast cancer incidence can be attributed to women stopping hormone therapy

Read the entire AACR press release here.