Researchers analyzed data from the SEER (Surveillance, Epidemiology and End Results) registry, which is maintained by the National Cancer Institute. They identified 14,764 women, age 20 to 39, who were diagnosed with early-stage breast cancer between 1990 and 2007. Forty-five percent of the women had breast-conservation surgery, and 55 percent had a mastectomy. Patients who received breast-conservation therapy were older and had smaller, lower-grade tumors and less lymph-node involvement. The median follow-up was nearly six years, although some patients were followed for 10 years, 15 years and beyond. All of the breast cancers were early-stage. Sixty-four percent of the patients were white.

To confirm the results of the study, the researchers did a "matched pair analysis, using a smaller group of 4,644 patients who had undergone breast-conservation therapy and mastectomy. Patients were matched for such factors as year of their diagnosis, age, grade, tumor size, number of positive lymph nodes, the number of nodes removed and their particular type of breast cancer, and still there was no difference in overall survival or survival specific to breast cancer. Similarly, a separate analysis was performed on the youngest group of patients, under age 33, again seeing no difference in outcomes.

The overall survival for those who had breast conservation therapy was 92.5 percent after five years, 83.5 percent after 10 years, and 77 percent after 15 years. That compares with 91.9 percent, 83.6 percent and 79.1 percent, respectively, for those who had mastectomies. In addition, the breast cancer-specific survival rates were similar between the two groups.

Source: University of Maryland Medical Center