EARLY STAGE BREAST CANCER AND PREOPERATIVE BREAST MAGNETIC RESONANCE IMAGING (MRI) USE: ESTIMATED LONG-TERM OUTCOMES AND COST-EFFECTIVENESS

Purpose: Preoperative breast MRI performed on women with a recent breast cancer diagnosis has increased in recent years, despite a lack of standard recommendations or definitive evidence of its value. Our objective was to quantify the long-term outcomes and cost-effectiveness of preoperative breast MRI use among women diagnosed with early stage (I-II) invasive unilateral breast cancer.

Methods: We developed a Markov state-transition model to compare the cost and quality-adjusted life years (QALYs) among women with vs. without receipt of preoperative breast MRI. We modeled five initial treatment patterns including: breast-conserving surgery (BCS), BCS with radiation therapy (RT), unilateral mastectomy, unilateral mastectomy with RT, and bilateral mastectomy. After initial treatment, women transitioned annually among three health states associated with their initial treatment: disease-free post initial treatment, disease-free post locoregional second cancer event, and post-metastatic cancer event. Initial treatment probabilities were adjusted estimates from logistic regression models from two data sources: Breast Cancer Surveillance Consortium linked with Medicare (BCSC-Medicare); Surveillance, Epidemiology, and End Results linked with Medicare (SEER-Medicare). Various ages of diagnosis (46, 56, 66) and time horizons (10, 20, 30 years), were used to model numerous scenarios. All second cancer event probabilities were obtained from published randomized control trials. All costs were adjusted to 2015 USD. Both costs and QALYs were discounted at an annual rate of 3%.

Results: Regardless of age at diagnosis, length of time post-diagnosis modeled, and initial treatment data source used, receiving an MRI is the preferred strategy due to increased QALYs compared to no receipt of MRI (Figure). All strategies evaluated incurred increased costs, although all were found to have an incremental cost effectiveness ratio (ICER) below the accepted threshold ($100,000/QALY). Both age of diagnosis and time horizon impacted the results.

Conclusions: Preoperative MRI use among women diagnosed with early stage breast cancer had improved health outcomes at a slightly increased cost. Further clinical investigation to evaluate the impact of breast MRI on health outcomes is warranted.