Solitary, Well-Circumscribed, T2 Hyperintense Masses on MRI Have Very Low Malignancy Rates

The Role of MRI in Breast Cancer and Breast Conservation Therapy

Contrast-enhanced breast MRI has an established role in aiding in the detection, evaluation, and management of breast cancer. This article discusses MRI sequences, the clinical utility of MRI, and how MRI has been evaluated for use in breast radiotherapy treatment planning. We highlight the contribution of MRI in the decision-making regarding selecting appropriate candidates for breast conservation therapy and review the emerging role of MRI-guided breast radiotherapy.

MRI-visualized T2 hyperintense breast lesions: identifying clinical and imaging factors linked to malignant biopsy outcomes

PURPOSE

To determine the malignancy rate for MRI-guided breast biopsies performed for T2 hyperintense breast lesions and to assess additional clinical and MRI characteristics that can predict benign and malignant outcomes.

METHODS

A retrospective chart review of consecutive MRI-guided breast biopsies performed in two tertiary hospitals was conducted over two years. Biopsies performed for T2 hyperintense lesions were selected, and further lesion imaging characteristics and patient risk factors were collected. Univariate and multivariate modeling regression were used to determine additional imaging and patient factors associated with malignant outcomes for biopsies of T2 hyperintense lesions.

RESULTS

Out of 369 MRI-guided breast biopsies, 100 (27%) were performed for T2 hyperintense lesions. Two biopsy-proven benign lesions were excluded as the patient was lost on follow-up. With a study cohort of 98 lesions, the final pathology results were benign for 80 (80%) of these lesions, while 18 (18%) were malignant. Using multivariate logistic modeling, patient age > 50 (OR 5.99 (1.49, 24.08 95% CI), p < 0.05) and lesion size > 3 cm (OR 5.54 (1.54-18.7), p < 0.01) were found to be important predictors of malignant outcomes for MRI biopsies performed for T2 hyperintense lesions.

CONCLUSION

Our study observed a high malignancy rate, challenging the assumption that T2 hyperintensity can be considered a benign imaging characteristic for otherwise suspicious MRI-detected lesions. Decision-making regarding tissue sampling should be made based on a thorough evaluation of more reliable additional demographic and imaging factors, including patient age and lesion size.

Abbreviated Breast MRI Utilization: A Survey of the Society of Breast Imaging

OBJECTIVE

To survey Society of Breast Imaging (SBI) membership on their use of abbreviated breast MRI to understand variability in practice patterns.

METHODS

A survey was developed by the SBI Patient Care and Delivery committee for distribution to SBI membership in July and August 2021. Eighteen questions queried practice demographics and then abbreviated breast MRI practices regarding initial adoption, scheduling and finances, MRI protocols, and interpretations. Comparisons between responses were made by practice demographics.

RESULTS

There were 321 respondents (response rate: 15.3%), of whom 25% (81/321) currently offer and 26% (84/321) plan to offer abbreviated breast MRI. Practices in the South (37/107, 35%) and Midwest (22/70, 31%) were more likely to offer abbreviated MRI (P = 0.005). Practices adopted many strategies to raise awareness, most directed at referring providers. The mean charge to patients was $414, and only 6% of practices offer financial support. The median time slot for studies is 20 minutes, with only 15% of practices using block scheduling of consecutive breast MRIs. Regarding MRI protocols, 64% (37/58) of respondents included only a single first-pass post-contrast sequence, and 90% (52/58) included T2-weighted sequences. Patient eligibility was highly varied, and a majority of respondents (37/58, 64%) do not provide any recommendations for screening intervals in non-high-risk women.

CONCLUSION

Abbreviated breast MRI utilization is growing rapidly, and practices are applying a variety of strategies to facilitate adoption. Although there is notable variability in patient eligibility, follow-up intervals, and costs, there is some agreement regarding abbreviated breast MRI protocols.

BI-RADS 3 Assessment on MRI: A Lesion-Based Review for Breast Radiologists

Unlike mammography and US, limited data exist to establish well-defined criteria for MRI findings that have a ≤2% likelihood of malignancy. Therefore, determining which findings are appropriate for a BI-RADS 3 assessment on MRI remains challenging and variable among breast radiologists. Emerging data suggest that BI-RADS 3 should be limited to baseline MRI examinations (or examinations with less than two years of prior comparisons) performed for high-risk screening and only used for masses with all of the typical morphological and kinetic features suggestive of a fibroadenoma or dominant enhancing T2 hypointense foci that is distinct from background parenchymal enhancement and without suspicious kinetics. This article presents an updated discussion of BI-RADS 3 assessment (probably benign) for breast MRI using current evidence.

Implementation of Abbreviated Breast MRI for Screening: AJR Expert Panel Narrative Review

Abbreviated breast MRI (AB-MRI) is being rapidly adopted to harness the high sensitivity of screening MRI while addressing issues related to access, cost, and workflow. The successful implementation of an ABI-MRI program requires collaboration across administrative, operational, financial, technical, and clinical providers. Institutions must be thoughtful in defining AB-MRI patient eligibility and providing recommendations for screening intervals, as existing practices are heterogeneous. Similarly, there is no universally accepted AB-MRI protocol, though guiding principles should harmonize abbreviated and full protocols while being mindful of scan duration and table time. The interpretation of AB-MRI will be a new experience for many radiologists and may require a phased rollout as well as a careful audit of performance metrics over time to ensure benchmark metrics are achieved. AB-MRI finances, which are driven by patient self-payment, will require buy-in from hospital administration with the recognition that downstream revenues will be needed to support initial costs. Finally, successful startup of an AB-MRI program requires active engagement with the larger community of patients and referring providers. As AB-MRI becomes more widely accepted and available, best practices and community standards will continue to evolve to ensure high quality patient care.

Image-guided Procedure Versus 2-year Follow-up for a BI-RADS 3 Probably Benign Lesion: A Cost Comparison Analysis

OBJECTIVE

Perform a comparison between the costs of image-guided breast procedures versus 2-year imaging follow-up for findings classified as BI-RADS assessment category 3-probably benign.

METHODS

The national payment amount costs at non-facility locations were obtained from the Centers for Medicare and Medicaid Services physician fee schedule for breast imaging-related Current Procedural Terminology codes. Total costs were calculated and compared for management algorithms of 2-year imaging follow-up of a BI-RADS 3 lesion from 2018 through 2019 versus performing an image-guided procedure of the lesion in 2018 after the initial diagnostic imaging.

RESULTS

Two-year mammographic follow-up of a BI-RADS 3 finding costs $484. This was less than a stereotactic-guided breast biopsy, which cost at least $1055. Two-year follow-up for a probably benign US finding cost $615 compared to $1173 for the least expensive US-guided breast biopsy scenario. For breast MRI, 2-year imaging follow-up cost $1510, which was also less than most MRI-guided breast biopsy scenarios. The one exception in which biopsy costs less than 2-year imaging follow-up was in the setting of an MRI-guided biopsy in the average-risk population without a post-benign biopsy follow-up breast MRI; in this setting, MRI biopsy cost $1235.

CONCLUSION

In 2018-2019, 2-year imaging follow-up of a BI-RADS 3 finding continues to be less costly than an immediate procedure, except for MRI-guided breast biopsy in the average-risk population without a post-benign biopsy follow-up MRI.