Is There an Expiration Date on Breast Cancer Medications?

Breast cancer treatments may stop working after three years

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) After chemotherapy, surgery and/or radiation, most breast cancer survivors take medications for at least 5 years to prevent the dreaded disease from returning. That may change.

New research suggests that breast cancer treatments designed to reduce the risk of a recurrence may lose their effectiveness once the patient survives the first three-year danger zone.

Ismail Jatoi, M.D., Ph.D., at the Cancer Therapy & Research Center at The University of Texas Health Science Center at San Antonio, examined data and hazard curves that looked at timelines for recurrence.

"Medications designed to keep breast cancer from returning may not be effective after three years."

He and colleagues concluded that breast cancer is a chronic disease that may sometimes return many years after initial diagnosis and treatment. The paper's authors suggest drug studies should be redesigned to take this into account.

"The current paradigm that we have is that these drugs, over the lifetime of the patient, have a constant effect,” said Jatoi, chief of surgical oncology at the Health Science Center and the paper’s lead author. “What we’ve suggested in this paper is that’s not really the case. What we’re seeing is that some drugs have an initial effect. The effect of the drug diminishes after about three years.”

Dr. Jatoi said it would make sense to design trials to follow patients for 8 or 9 years, or possibly begin studies that take patients who are 5- or 7-year breast cancer survivors.

“This is important because we’re seeing more and more long-term breast cancer survivors,” Dr. Jatoi said.

There are roughly 2.5 million breast cancer survivors currently living in the United States. The study findings were published online in the Journal of Clinical Oncology.

Reviewed by: 
Review Date: 
May 10, 2011
Last Updated:
May 26, 2011