Contralateral risk-reducing mastectomy in young breast cancer patients with and without genetic cancer risk assessment.

BACKGROUND: Decisions regarding contralateral risk-reducing mastectomy (CRRM) among women diagnosed with unilateral breast cancer can potentially be influenced by age at diagnosis and other factors. In this study, we examined the use of CRRM before versus after genetic cancer risk assessment (GCRA) in women diagnosed with breast cancer before age 50.
METHODS: We conducted a retrospective analysis of women with invasive breast cancer diagnosed before age 50 who were seen for GCRA between October 1996 and March 2005. Associations between the presence of generally accepted indications for risk-reducing surgery among women who had CRRM and the timing of GCRA were examined.
RESULTS: The cohort included 378 women, of whom 57 had CRRM pre-GCRA and 45 had CRRM post-GCRA after a median follow-up of 26 months. Women who had CRRM pre-GCRA were more likely to not have a generally accepted indication for the procedure than those who did after GCRA (odds ratio [OR] 5.3, 95% confidence interval [95% CI] 1.6-17.8, P = .007). Women diagnosed with breast cancer before BRCA genetic testing became clinically available (1997) were more likely to have had CRRM pre-GCRA than those who were diagnosed more recently (OR 2.9, 95% CI 1.6-5.2, P = .0003).
CONCLUSION: When personal and family history was carefully examined, a substantial proportion of women seen in our clinic did not have a clear indication for CRRM. Decreased use of empiric CRRM among women diagnosed after 1997 may indicate increased awareness and use of GCRA. Thus, judicious application of GCRA may help focus use of surgical risk reduction measures to the most risk-appropriate patients.