Preoperative breast MRI in early-stage breast cancer.

Rapid uptake of new imaging technology is a major contributor to rising healthcare costs. Preoperative breast magnetic resonance imaging (MRI) for patients with early-stage breast cancer has dramatically increased in use without the evidence of improved outcomes compared to standard assessment and is associated with higher rates of mastectomy. A decision analytic model was developed to evaluate the impact of adding breast MRI to the preoperative evaluation of women with early-stage breast cancer who were candidates for breast-conserving therapy on patient outcomes measured in quality-adjusted life years (QALYs). Model inputs, including survival, recurrence rates, and health utilities, were obtained from a comprehensive literature review. One-way sensitivity analyses were performed to estimate threshold values for key parameters at which adding MRI would become the optimal imaging strategy over standard assessment. Preoperative MRI resulted in 17.77 QALYs compared to 17.86 QALYs with standard assessment, a decrease of 0.09 QALYs or 34 days. In sensitivity analyses, standard assessment was associated with better patient outcomes than preoperative breast MRI across all plausible probabilities for mastectomy, local recurrence, and health utilities. For routine preoperative breast MRI to become the optimal strategy, the conversion rate to mastectomy after preoperative MRI would need to be <1 % (versus the range of 3.6-33 % reported in the literature). Routine preoperative breast MRI appears to confer no advantage over the standard diagnostic evaluations for early-stage breast cancer and may lead to worse patient outcomes.