Breast cancer-specific mortality rates were similar in women who received bilateral or unilateral mastectomy, according to a matched cohort analysis involving >41,500 individuals. Participants were diagnosed with unilateral breast cancer between 1998 and 2002. Investigators used a 4-to-1 matched cohort of patients that included ~14,000 patients, and looked at cause-specific death. Among the results:

• 93% of patients had unilateral and the remainder bilateral mastectomy.
• Under 4-to-1 matching, ~11,200 unilateral mastectomy and ~2,800 bilateral mastectomy patients were included.
• Risk of breast cancer-specific death was similar in both groups.

The authors noted that clinicians should consider patient preference and alternative benefits of bilateral mastectomy.