Genes Predict Breast Cancer Future

Medically Reviewed by Charlotte E. Grayson Mathis, MD
From the WebMD Archives

Jan. 30, 2002 -- Determining which women need aggressive breast cancer treatment can be challenging. But in a new study, researchers say they have developed a technique that helps predict the future better than any method available.

Doctors have been unable to master the fine art of predicting how likely a woman's breast cancer is to come back after treatment. For this reason, many women get treatments they may not need, according to researchers in the Jan. 31 issue of Nature.

Doctors treat breast cancer based on certain characteristics of the tumor, such as the size of the tumor and how far it has spread. If the doctors find that the cancer hasn't spread -- or metastasized -- to other organs, the tumor is removed and radiation therapy is typically given to eliminate any remaining cancer cells. But in some cases, the tumor spreads later.

Many women also get chemotherapy or hormone treatment, such as Nolvadex or tamoxifen. They decrease the chance of spread by one-third, according to the study researchers. But, 70% to 80% of women would probably have survived without it, they write.

Thus, scientists need to figure out which women need more aggressive treatment to prevent cancer spread, writes Carlos Caldas, MD, in an editorial accompanying the study. Caldas is with the University of Cambridge in England.

Researchers Stephen H. Friend, MD, PhD, and colleagues analyzed genes in the tumors of 117 women after surgery. None of the women had spread of the tumor to their lymph nodes -- the first place that breast cancer usually spreads.

They were able to identify a particular setup of genes in the tumor that predicted which women were likely to develop spread of the cancer. This could potentially tell doctors that they need to treat these women with chemotherapy and possibly hormone treatment. It could also save some women from difficult treatment they may not need.

This technique of identifying a bad genetic makeup will outperform all other current methods of predicting breast cancer results, according to the researchers.

An effective test to tell who would benefit from chemotherapy or hormone treatment would be very helpful to both doctors and women with breast cancer. It would be a great step ahead for breast cancer treatment and hopefully other types of cancer as well.