The document evaluates the cost-effectiveness of contralateral prophylactic mastectomy (CPM) compared to routine surveillance for patients with unilateral breast cancer. Using a Markov model, it found that CPM is cost-effective for patients under 70, providing more quality-adjusted life years (QALYs) at a lower cost for BRCA-positive patients, while for non-BRCA patients, its cost-effectiveness is highly sensitive to assumptions about quality of life. The study emphasizes the need for individualized treatment strategies based on patient characteristics.