Radiation Therapy Relatively Ineffective for Treating Early-stage Estrogen-receptor Positive Breast Cancer in Older Women
Tamoxifen plus breast-conserving surgery proved a more effective combination without radiation therapy in women 70 or older with early-stage breast cancer, based on the findings of a phase III randomized trial recently reported at the American Society of Clinical Oncology Annual Meeting.
The study showed that "death from breast cancer is a very rare event among women with these small cancers," said Kevin Hughes, M.D., with the Massachusetts General Hospital in Boston, in a news article in the June 1, 2010, online NCI Cancer Bulletin.
The trial conducted by the Cancer and Leukemia Group B, Eastern Cooperative Oncology Group and Radiation Therapy Oncology Group enrolled 636 women between 1994 and 1999, with 319 receiving tamoxifen alone after surgery and 317 receiving chemo plus radiation therapy. All participants had early-stage, estrogen-receptor (ER) positive breast cancer.
Adding radiation therapy to tamoxifen reduced cancer recurrence in the same breast by 6 percent, but did not affect overall survival, breast-cancer-specific survival, cancer spread or the need for a later mastectomy. The median follow-up was 10.5 years after treatment, with the 10-year breast-cancer-specific survival 98 percent for women who received tamoxifen alone and 96 percent for those who were also treated with radiation.
"Older women often have small tumors that are ER-positive, without evidence of spread to the lymph nodes. This [study] is certainly practice-affirming and may be potentially practice changing," said Douglas Blayney, M.D., president of ASCO. "Many [older] women…elect to defer radiation therapy. This gives us some comfort as physicians in supporting that decision…and maybe it will change the recommendations we make to our patients."
|
