Low Compliance in a Health-Conscience Spending Era Likely Helps Obviates the Need for 6 month BI-RADS 3 Breast MRI Follow-up After 1 year.

Abstract

The goal of our IRB-approved study was to assess if a follow-up MRI every 6 months for 2 years is the most appropriate short-interval follow-up schedule. 203 breast MRI exams were performed from October 2009 to January 2014 as part of a BI-RADS 3 follow-up representing 2.6% of all breast MRIs (7,822) performed. We performed a retrospective longitudinal medical records review of compliance; malignancy rate of BI-RADS 3 exams; and average time and number of breast MRIs necessary prior to definitive disposition. While 77.8% eventually returned, only 45.5% of patients were compliant with follow-up at or near 6 months (4.5-7.5 months). Of those who eventually returned, it took an average of 1.31 follow-up MRIs (95% CI: 1.20-1.43 exams) and 10.3 months (95% CI: 9.0-11.7 months) before definitive disposition. 93.5% of initial findings were dispositioned as benign after two follow-up MRI exams (malignancy rate: 0.98%). Our results lend support to the possibility that the follow-up interval for BI-RADS 3 breast MRIs could be lengthened to 12 months if additional follow-up MRIs are necessary after the first year of 6-month follow-up breast MRIs. Foremost, this appears to be a safe follow-up alternative since benign definitive disposition can usually be made in less than 1 year. Supplemental reasons include persistent low-patient compliance (as redemonstrated in our study) and the higher cost of breast MRI compared to mammogram/ultrasound follow-up. Finally, this paper's findings further support the suggested MRI follow-up interval in the newest BI-RADS atlas.