Cancer Treatment
Odds of breast cancer recurrence decline when radiation follows surgery

THE QUESTION Does having radiation treatment after breast cancer surgery make a difference in whether the cancer returns?

THIS STUDY combined and analyzed data from 17 studies, involving 10,801 women who had surgery for breast cancer in which part but not all of their breast was removed and who had been randomly assigned to have radiation treatment or no radiation after the surgery. In a 10-year span, 35 percent of the women who did not undergo radiation experienced a recurrence, compared with 19 percent of those who did have radiation. The chances of dying from breast cancer within 15 years also fell with radiation treatment, from 20 to 17 percent. For women whose cancer had not spread to the lymph nodes, the rate of recurrence was 16 percent with radiation treatment, compared with 31 percent without it. If the cancer had spread, the risk of recurrence dropped 21 percentage points with radiation: 43 percent vs. 64 percent without it.

WHO MAY BE AFFECTED? Women with breast cancer who have a lumpectomy or other type of breast-conserving surgery. Radiation aims to kill any microscopic bits of tumor that may remain. It’s estimated that one of every eight women born today will develop breast cancer at some point in her life.

CAVEATS Data included only first recurrences. The study began more than a decade ago; the authors noted that ongoing advances in screening and treatment methods for breast cancer may yield different results for future patients.

FIND THIS STUDY Oct. 20 online issue of the Lancet (www.
thelancet.com)
.

LEARN MORE ABOUT breast cancer at www.cancer.gov and www.cancer.org .

— Linda Searing

The research described in Quick Study comes from credible, peer-reviewed journals. Nonetheless, conclusive evidence about a treatment's effectiveness is rarely found in a single study. Anyone considering changing or beginning treatment of any kind should consult with a physician.