Abstract P4-02-01: Recall rates during breast cancer surveillance in high-risk women with dynamic contrast-enhanced magnetic resonance imaging every 6 months: Results from a single institution study

Abstract

Abstract Purpose: To compare recall rates and biopsy rates in high-risk women undergoing semi-annual dynamic contrast-enhanced magnetic resonance imaging compared to recommended annual DCE-MRI. Background: In high-risk women with BRCA1/BRCA2 mutations and/or a personal or family history of breast cancer, annual breast MRI has shown improved sensitivity and cancer detection compared to mammography and is recommended annually in addition to mammogram. The routine use of breast MRI screening in this patient population is not widespread due to concerns for higher recall rates and false positive biopsy results, which often contribute to higher healthcare costs and increased stress. Breast MRI screening acceptability is dependent on sensitivity and recall rates. The acceptable recall rate for breast MRI is generally considered to be between 6-12% based off the results from studies that used annual DCE-MRI screening. Methods: Between 2004 and 2016, a prospective cohort of high-risk women underwent semi-annual DCE-MRI and annual mammography. For subjects with BI-RADS score of 4 or 5 on DCE-MRI, biopsy was recommended. For subjects with BI-RADS score of 0 on DCE-MRI and/or BI-RADS scores of 0,4, or 5 on MG, further investigation by imaging was recommended and biopsy was performed if clinically appropriate. Tests with BI-RADS scores of 3 were discussed case-by-case. Recall was defined as women being recommended for further imaging (i.e. US and/or MG) in order to provide additional information. Women that are recalled may go on to have a subsequent biopsy based on the findings. Results: 295 women were recruited to the study; 44% of the study participants had mutations in BRCA1 or BRCA2. 2111 DCE-MRI screening tests and 1225 mammography were performed. The sensitivity and specificity was 93.7% and 96.6% respectively for DCE-MRI and 50% and 97.7% respectively for mammogram. The positive predictive value was 17% for MRI and 22% for mammography. Eighty-nine women had 106 recalls. 74 due to DCE-MRI imaging alone, 18 due to mammography alone, and 14 due to both image modalities. The recall rate was 4.2% for DCE-MRI and 2.6% for mammography. In total, 56 biopsies were performed. 3 DCIS and 13 invasive breast cancers were diagnosed. On average, 5.9 women would have to be recalled on DCE-MRI with 3.3 biopsies to diagnose one cancer case. 4 women would have to be recalled on mammography with 2.1 biopsies to diagnose one cancer. Conclusion: Semi-annual DCE-MRI screening in high-risk women demonstrated high sensitivity without substantially increasing recall rates or biopsy rates to an unacceptable value. Our single institution DCE MRI protocol achieved recall rates lower than those considered acceptable for annual MRI or mammography. This study demonstrates that with radiology reader expertise, careful clinical decision making, and improved MRI technology, it is possible to achieve recall rates lower than those achieved with annual mammography or MRI even when DCE-MRI screening exams occur more frequently than those currently recommended by guidelines. Additional data including QOL and cost effectiveness analysis will be presented. Citation Format: Whitaker KD, Abe H, Sheth D, Huo D, Yoshimatsu TF, Verp M, Zheng Y, Karczmar G, Guindalini R, Olopade OI. Recall rates during breast cancer surveillance in high-risk women with dynamic contrast-enhanced magnetic resonance imaging every 6 months: Results from a single institution study [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-02-01.