Outcomes of Density-Targeted Supplemental Breast Magnetic Resonance Imaging Screening by Breast Cancer Risk: Long-Term Health and Economic Considerations.

BACKGROUND

Federally mandated breast density notifications motivate consideration of supplemental breast magnetic resonance imaging (MRI).

OBJECTIVE

To evaluate supplemental breast MRI strategies.

DESIGN

Simulation of women at average to 4 times higher-than-average relative risk (RR) for breast cancer incidence undergoing screening digital breast tomosynthesis (DBT) with or without supplemental MRI.

DATA SOURCES: Breast Cancer Surveillance Consortium and literature.

TARGET POPULATION: Women aged 40 years or older.

TIME HORIZON: Lifetime.

PERSPECTIVE: U.S. federal payer.

INTERVENTION: Screening with DBT with or without breast density-targeted MRI by starting age (40, 45, or 50 years) and interval (annual or biennial).

OUTCOME MEASURES: Breast cancer deaths averted, false-positive biopsy recommendations, harm-benefit ratios, and incremental cost-effectiveness ratios (ICERs).

RESULTS OF BASE-CASE ANALYSIS: Across all starting ages and intervals, DBT averted 7.4 to 10.5 breast cancer deaths per 1000 average-risk women screened and 23.2 to 33.6 per 1000 women with 4 times higher-than-average risk. Across all RR levels, DBT with supplemental MRI for women with extremely dense breasts (DBT+MRId) averted 0.1 to 0.8 additional breast cancer deaths and resulted in 22 to 186 additional false-positive biopsy recommendations. False-positive biopsies per breast cancer death averted for biennial DBT+MRId for women with 2 times higher-than-average risk were similar to those associated with DBT in average-risk women. For all risk groups, biennial DBT+MRId starting at age 50 years was more effective but less cost-effective than DBT starting at age 45 years.

RESULTS OF SENSITIVITY ANALYSIS: The ICERs were sensitive to cancer risk, MRI costs, and false-positive biopsy rates.

LIMITATION: Subgroups considered risk and breast density only.

CONCLUSION

Supplemental MRI for women aged 40 years or older with extremely dense breasts and higher-than-average risk (RR ≥2.0) had harm-benefit ratios similar to biennial DBT alone and could be cost-effective if MRI costs and false-positive biopsy rates are reduced.

PRIMARY FUNDING SOURCE: National Cancer Institute.