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A new international competition aims to speed up the development of AI models that can assist radiologists in detecting suspicious lesions from hundreds of millions of pixels in 3D mammograms. The top three winning teams compare notes.

Multiple studies have demonstrated screening mammography’s ability to decrease mortality in average risk women. It is also recognized that women at high risk for breast cancer who choose surveillance benefit from additional imaging strategies for cancer detection in addition to mammography alone. Contrast-enhanced breast MRI has become a standard and accepted tool in the screening evaluation of women with a high risk of breast cancer. However, despite recognition of MRI’s ability to detect breast cancer in the screening setting in a high-risk population, there are still questions surrounding the use of breast MRI in the screening environment. This chapter will provide an overview of breast screening MRI indications and current guidelines and will also review the evidence supporting the use of screening breast MRI.

The role of breast MRI in patients with newly diagnosed breast cancer is controversial. Preoperative MRI is highly sensitive and accurate in assessing tumor size, extensive intraductal component (EIC), and in detection of additional sites of disease. It also has utility in assessing chest wall, nipple-areolar complex, and nodal involvement. Yet there are conflicting results in whether the use of preoperative MRI improves re-excision rate, local recurrence rate, and ultimately, survival. MRI has also been associated with overestimation of disease and increased mastectomy rates, and may contribute to treatment delay. Nevertheless, certain subgroups of patients may benefit more from preoperative MRI than others, including those with invasive lobular cancer (ILC), dense breasts, and those at elevated risk for breast cancer.

To examine heterogeneous breast cancer through intravoxel incoherent motion (IVIM) histogram analysis.This HIPAA-compliant, IRB-approved retrospective study included 62 patients (age 48.44 ± 11.14 years, 50 malignant lesions and 12 benign) who underwent contrast-enhanced 3 T breast MRI and diffusion-weighted imaging. Apparent diffusion coefficient (ADC) and IVIM biomarkers of tissue diffusivity (Dt), perfusion fraction (fp), and pseudo-diffusivity (Dp) were calculated using voxel-based analysis for the whole lesion volume. Histogram analysis was performed to quantify tumour heterogeneity. Comparisons were made using Mann-Whitney tests between benign/malignant status, histological subtype, and molecular prognostic factor status while Spearman's rank correlation was used to characterize the association between imaging biomarkers and prognostic factor expression.The average values of the ADC and IVIM biomarkers, Dt and fp, showed significant differences between benign and malignant lesions. Additional significant differences were found in the histogram parameters among tumour subtypes and molecular prognostic factor status. IVIM histogram metrics, particularly fp and Dp, showed significant correlation with hormonal factor expression.Advanced diffusion imaging biomarkers show relationships with molecular prognostic factors and breast cancer malignancy. This analysis reveals novel diagnostic metrics that may explain some of the observed variability in treatment response among breast cancer patients.• Novel IVIM biomarkers characterize heterogeneous breast cancer. • Histogram analysis enables quantification of tumour heterogeneity. • IVIM biomarkers show relationships with breast cancer malignancy and molecular prognostic factors.

To determine the utility of short-interval follow-up after benign concordant MRI-guided breast biopsy. Institutional review board approved, retrospective review of consecutive biopsies performed over 3 years (2007–10) yielded 170 women with 188 lesions that were considered benign concordant. Indication for original study, biopsy results, follow-up recommendations, compliance and outcomes of subsequent MRI and mammography examinations were reviewed. The most common indication for breast MRI was high-risk screening 119/170 (70 %). Overall, 59 % of lesions (113/188) had follow-up MRI. Of those lesions (n = 113), 43 % (49/113) presented within 7 months, 26 % (29/113) presented within 8–13 months, 11.5 % (13/113) presented within 14–22 months, and 19 % (22/113) presented after 23 months. At initial follow-up, 37 % of lesions were stable and 61 % were decreased in size. Three lesions were recommended for excision based on follow-up imaging with one malignancy diagnosed 2 years following biopsy. One additional patient had MRI-detected bilateral cancers remote from the biopsy site 3 years after biopsy. Overall cancer yield of lesions with follow-up MRI was 0.9 % (1/113); no cancers were detected at 6 months. Our data suggests that 6-month follow-up may not be required and that annual screening MRI would be acceptable to maintain a reasonable cancer detection rate. • Follow-up recommendations after benign concordant MRI-guided breast biopsy remain controversial. • Cancer detection rate was 0.9 % overall with no cancers detected at 6 months. • Short-interval follow-up after benign concordant MRI-guided breast biopsy may not be necessary.

To evaluate the image quality of T1-weighted fat-suppressed breast MRI at 7 T and to compare 7-T and 3-T images.Seventeen subjects were imaged using a 7-T bilateral transmit-receive coil and 3D gradient echo sequence with adiabatic inversion-based fat suppression (FS). Images were graded on a five-point scale and quantitatively assessed through signal-to-noise ratio (SNR), fibroglandular/fat contrast and signal uniformity measurements.Image scores at 7 and 3 T were similar on standard-resolution images (1.1 × 1.1 × 1.1-1.6 mm(3)), indicating that high-quality breast imaging with clinical parameters can be performed at 7 T. The 7-T SNR advantage was underscored on 0.6-mm isotropic images, where image quality was significantly greater than at 3 T (4.2 versus 3.1, P ≤ 0.0001). Fibroglandular/fat contrast was more than two times higher at 7 T than at 3 T, owing to effective adiabatic inversion-based FS and the inherent 7-T signal advantage. Signal uniformity was comparable at 7 and 3 T (P 0.05). Similar 7-T image quality was observed in all subjects, indicating robustness against anatomical variation.The 7-T bilateral transmit-receive coil and adiabatic inversion-based FS technique produce image quality that is as good as or better than at 3 T.• High image quality bilateral breast MRI is achievable with clinical parameters at 7 T. • 7-T high-resolution imaging improves delineation of subtle soft tissue structures. • Adiabatic-based fat suppression provides excellent fibroglandular/fat contrast at 7 T. • 7- and 3-T 3D T1-weighted gradient-echo images have similar signal uniformity. • The 7-T dual solenoid coil enables bilateral imaging without compromising uniformity.

Objective. To define and compare early lesions associated with slipped capital femoral epiphysis (SCFE) on magnetic resonance imaging (MRI), computed tomography (CT) and radiography. Design and patients. Thirteen patients with 15 symptomatic hips due to SCFE underwent radiography and MRI; CT was performed in 12 patients. SCFE was graded on radiographs, head/neck angles and qualitative changes were evaluated on CT, and morphologic/signal abnormalities were determined on MRI. Results. Physeal widening, apparent on T1-weighted MRI, was evident in every case of SCFE, including one presumed “pre-slip.” T2-weighted images demonstrated synovitis and marrow edema but obscured physeal abnormalities. CT head/neck angles ranged from 4–57° for symptomatic to 0–14° for asymptomatic hips. Physeal and metaphyseal changes were variably identified on both radiographs and CT in all cases of SCFE, but not in the pre-slip. Conclusion. MRI clearly delineates physeal changes of both pre-slip and SCFE, and demonstrates very early changes at a time when radiographs and CT may appear normal.