The Impact of Mammographic, Radiologist, and Patient Factors on the Likelihood of Probably Benign (BI-RADS 3) Assessment at Diagnostic Mammography.

OBJECTIVE: To evaluate the association of mammographic, radiologist, and patient factors on BI-RADS 3 assessment at diagnostic mammography in patients recalled from screening mammography. METHODS: This Institutional Review Board-approved retrospective study of consecutive unique diagnostic mammography examinations in asymptomatic patients recalled from screening mammography March 5, 2014, to December 31, 2019, was conducted in a single large United States health care institution. Mammographic features (mass, calcification, distortion, asymmetry), breast density, prior examination, and BI-RADS assessment were extracted from reports by natural language processing. Patient age, race, and ethnicity were extracted from the electronic health record. Radiologist years in practice, recall rate, and number of interpreted diagnostic mammograms were calculated. A mixed effect logistic regression model evaluated factors associated with likelihood of BI-RADS 3 compared with other BI-RADS assessments. RESULTS: A total of 12 080 diagnostic mammography examinations were performed during the study period, yielding 2010 (16.6%) BI-RADS 3 and 10 070 (83.4%) other BI-RADS assessments. Asymmetry (odds ratio [OR] = 6.49, P <.001) and calcification (OR = 5.59, P <.001) were associated with increased likelihood of BI-RADS 3 assessment; distortion (OR = 0.20, P <.001), dense breast parenchyma (OR = 0.82, P <.001), prior examination (OR = 0.63, P = .01), and increasing patient age (OR = 0.99, P <.001) were associated with decreased likelihood. Mass, patient race or ethnicity, and radiologist factors were not significantly associated with BI-RADS 3 assessment. Malignancy rate for BI-RADS 3 lesions was 1.6%. CONCLUSION: Asymmetry and calcifications had an increased likelihood of BI-RADS 3 assessment at diagnostic evaluation with low likelihood of malignancy, while radiologist features had no association.

Positive predictive value of axillary lymph node cortical thickness and nodal, clinical, and tumor characteristics in newly diagnosed breast cancer patients.

PURPOSE: Axillary lymph nodes (LNs) with cortical thickness > 3 mm have a higher likelihood of malignancy. To examine the positive predictive value (PPV) of axillary LN cortical thickness in newly diagnosed breast cancer patients, and nodal, clinical, and tumor characteristics associated with axillary LN metastasis. METHODS: Retrospective review of axillary LN fine needle aspirations (FNAs) performed 1/1/2018-12/31/2019 included 135 axillary FNAs in 134 patients who underwent axillary surgery. Patient demographics, clinical characteristics, histopathology, and imaging features were obtained from medical records. Hypothesis testing was performed to identify predictors of axillary LN metastasis. RESULTS: Cytology was positive in 72/135 (53.3%), negative in 61/135 (45.2%), and non-diagnostic in 2/135 (1.5%). At surgery, histopathology was positive in 84 (62.2%) and negative in 51 (37.8%). LN cortices were thicker in metastatic compared to negative nodes (p < 0.0001). PPV of axillary LNs with cortical thickness ≥ 3 mm, ≥ 3.5 mm, ≥ 4 mm and, ≥ 4.25 mm was 0.62 [95% CI 0.53, 0.70], 0.63 [0.54, 0.72], 0.67 [0.57, 0.76] , and 0.74 [0.64, 0.83], respectively. At multivariable analysis, abnormal hilum (OR = 3.44, p = 0.016) and diffuse cortical thickening (OR = 2.86, p = 0.038) were associated with nodal metastasis. CONCLUSION: In newly diagnosed breast cancer patients, increasing axillary LN cortical thickness, abnormal fatty hilum, and diffuse cortical thickening are associated with nodal metastasis. PPV of axillary LN cortical thickness ≥ 3 mm and ≥ 3.5 mm is similar but increases for cortical thickness ≥ 4 mm. FNA of axillary LNs with cortex < 4 mm may be unnecessary for some patients undergoing sentinel LN biopsy.

Experience of a single healthcare system with screening mammography before and after COVID-19 shutdown.

PURPOSE: To evaluate COVID-19's longitudinal impact on screening mammography volume trends. METHODS: HIPAA-compliant, IRB-approved, single institution, retrospective study of screening mammogram volumes before (10/21/2016-3/16/2020) and greater than two years after (6/17/2020-11/30/2022) a state-mandated COVID-19 shutdown (3/17/2020-6/16/2020) were reviewed. A segmented quasi-poisson linear regression model adjusting for seasonality and network and regional population growth compared volume trends before and after the shutdown of each variable: age, race, language, financial source, risk factor for severe COVID-19, and examination location. RESULTS: Adjusted model demonstrated an overall increase of 65 screening mammograms per month before versus a persistent decrease of 5 mammograms per month for >2 years after the shutdown (p < 0.0001). In subgroup analysis, downward volume trends were noted in all age groups <70 years (age < 50: +9/month before vs. -7/month after shutdown; age 50-60: +17 vs. -7; and age 60-70: +21 vs. -2; all p < 0.001), those identifying as White (+55 vs. -8, p < 0.0001) and Black (+4 vs. +1, p = 0.009), all financial sources (Medicare: +22 vs. -3, p < 0.0001; Medicaid: +5 vs. +2, p = 0.006; private insurance/self-pay: +38 vs. -4, p < 0.0001), women with at least one risk factor for severe COVID-19 (+30 vs. -48, p < 0.0001), and screening mammograms performed at a hospital-based location (+48 vs. -14, p = 0.0001). CONCLUSION: The screening mammogram volume trend more than two years after the COVID-19 shutdown has continued to decline for most patient populations. Findings highlight the need to identify additional areas for education and outreach.

Mixed and Purely Hyperechoic Breast Masses: A Radiologic-Pathologic Review.

Breast US is a mainstay of modern-day breast imaging, especially in the diagnostic and interventional realm. The BI-RADS atlas described six echo patterns relative to the subcutaneous mammary fat: anechoic, hypoechoic, complex cystic and solid, isoechoic, heterogeneous, and hyperechoic. Hyperechoic breast masses demonstrate increased echogenicity relative to subcutaneous mammary fat or equal to fibroglandular tissue. Pathologically, the hyperechoic pattern at breast US results from the intermingling of different components: adipose tissue, fibrous tissue or stroma, secretions, blood or vascularity, and calcifications. Most hyperechoic masses are benign, especially homogeneously hyperechoic masses. However, hyperechogenicity does not exclude malignancy. Two echo patterns have been identified in hyperechoic malignant lesions, including those with a hypoechoic center and hyperechoic rim known as the rim pattern and a mass with hyperechoic areas distributed through the mass known as a dispersed pattern. This article aims to illustrate the echogenic patterns of breast lesions and various benign and malignant hyperechoic breast lesions with radiologic-pathologic correlation and to increase awareness of heterogeneously hyperechoic breast lesions as a manifestation of malignancy.

Breast Malignancies After Mastectomy With Autologous or Implant Reconstruction.

There are multiple indications for mastectomy for breast cancer, including extent of tumor, inability to achieve negative margins after re-excision, patient preference, or prevention in women with a high lifetime risk of breast cancer. Multiple types of autologous or implant reconstruction options are available for cosmesis. Although rare, breast cancers after mastectomy can occur, and it is important for both surgeons and radiologists to be aware of the associated risk factors, common locations, and classic imaging features of these malignancies. This article reviews the types of mastectomies, reconstruction options, and information about the location, presentation, and prognosis of cancers in the reconstructed breast.

Male Breast Disease: What the Radiologist Needs to Know.

The male breast is susceptible to a variety of benign and malignant processes, many of which clinically present as a palpable finding, focal pain, or breast enlargement. Gynecomastia is the most common abnormality in the male breast and must be distinguished from malignancy. Imaging of the symptomatic male breast begins with a diagnostic mammogram in a patient ≥25 years and targeted ultrasound in a patient <25 years. If the breast finding is incompletely imaged or occult at mammography, targeted ultrasound must be performed. Similarly, if the breast finding is suspicious at targeted ultrasound in a younger patient, mammography must be performed. After a complete diagnostic evaluation, suspicious findings require biopsy because of overlap in clinical and imaging features of benign and malignant pathologies. Although no breast cancer screening program exists for men due to the <1% incidence of breast cancer, transgender male to female patients >50 years and treated with exogenous hormone therapy for >5 years should undergo breast cancer screening. This paper will review the anatomy of the male breast, appropriate imaging of the symptomatic male breast, gynecomastia and other benign conditions, and male breast cancer and other malignant conditions. Finally, we will discuss imaging of the transgender patient.

Ultrasound Features of Mammographic Developing Asymmetries and Correlation With Histopathologic Findings.

OBJECTIVE: The purpose of this study is to review the ultrasound (US) features of developing asymmetries and correlate them with histopathologic findings. MATERIALS AND METHODS: We searched the mammography database of an academic medical center, affiliated cancer center, and two ambulatory imaging facilities from 2009 to 2012 and identified 201 patients with developing asymmetries, 187 of whom had US at the time of, or within 1 month of, diagnostic mammography evaluation. Seventy-five (40.1%) of these 187 patients had a US correlate, and three additional patients had a positive second-look US after MRI (US results were initially negative), and one patient had a US correlate for a newly palpable developing asymmetry 1 month after receiving a BI-RADS category 3 mammography-only assessment. These 78 developing asymmetries with US correlates comprised the study cases. US features were obtained by consensus image review; patient demographic characteristics and outcomes were obtained from the electronic medical record. RESULTS: Thirty-six of 78 US correlates (46.2%) were masses, the echotexture of which was as follows: 26 (72.2%) were hypoechoic, four (11.1%) were hyperechoic, three (8.3%) were mixed hyperechoic and hypoechoic, and three (8.3%) were anechoic. Forty-two of 78 US correlates (53.8%) were nonmass findings, the echotexture of which was as follows: 24 (57.1%) were mixed hyperechoic and hypoechoic, 13 (31.0%) were hypoechoic, and five (11.9%) were hyperechoic. Twenty-one of 78 lesions (26.9%) were malignant; of these, eight were invasive ductal carcinoma, seven were invasive lobular carcinoma, three were mixed invasive ductal and lobular carcinoma, and three were ductal carcinoma in situ. Malignant findings on US included 17 masses (81.0%) (13 hypoechoic and four mixed hyperechoic and hypoechoic), and four nonmass findings (19.0%) (three mixed hyperechoic and hypoechoic and one hypoechoic). CONCLUSION: When present, US correlates for developing asymmetries are often nonmass findings with mixed echotexture. Most malignant developing asymmetries with US correlates present as a hypoechoic mass, but 19% present as a nonmass finding with either mixed hyperechoic and hypoechoic echotexture or hypoechoic echotexture.

Troubleshooting to Overcome Technical Challenges in Image-guided Breast Biopsy.

Image-guided breast biopsy with stereotactic, ultrasonographic, or magnetic resonance imaging guidance has become an integral component of every breast imaging program. It has many advantages over open surgical biopsy, including lower cost, lower patient morbidity, faster patient recovery, and minimal to no scarring, with equal accuracy to that of open surgical biopsy. Successful completion of a breast biopsy begins with thorough preprocedural planning to choose the appropriate imaging modality and most efficient biopsy approach. Patient mental and physical comorbidities, anticoagulation status, small or thin breasts, and breast implants, as well as lesion conspicuity and posterior, superficial, axillary, or subareolar location, pose technical challenges to successful image-guided breast biopsy that must be overcome. When biopsy is performed with use of a different imaging modality than that used to initially identify the target, careful preprocedural multimodality radiologic correlation, postprocedural identification of the biopsy marker location, and radiologic-pathologic correlation must be undertaken to ensure accurate biopsy of the intended target with use of the different modality. If, after employing all available strategic and procedural modifications, image-guided breast biopsy cannot be performed, then surgical excision of the intended target should be recommended at the time of biopsy cancellation to avoid a delay in diagnosis. This article reviews patient and lesion factors that pose technical challenges to successful breast biopsy and presents strategies and procedural modifications that aid in successful completion of breast biopsy in challenging situations. ©RSNA, 2017.

Radiation-Associated Angiosarcoma of the Breast: What the Radiologist Needs to Know.

OBJECTIVE: The purpose of this article is to describe the diagnosis, treatment, and follow-up of radiation-associated angiosarcoma (RAS) of the breast. CONCLUSION: Radiologists play an important role in the diagnosis of RAS, which may initially present clinically as erythema, ecchymosis, or skin thickening. Conventional imaging with mammography and ultrasound is less sensitive than MRI for the diagnosis of RAS. Follow-up CT is important to monitor treatment response.

Developing Asymmetries at Mammography: A Multimodality Approach to Assessment and Management.

A developing asymmetry is a focal asymmetry that is new or increased in conspicuity compared with the previous mammogram. It is challenging to evaluate, as it often looks similar to fibroglandular tissue at mammography. A developing asymmetry should be viewed with suspicion because it is an uncommon manifestation of breast cancer. Diagnostic mammography forms the foundation of diagnostic evaluation of a developing asymmetry and begins with additional spot compression, lateral, and/or rolled views to evaluate and localize it in three-dimensional space. Digital breast tomosynthesis can aid in evaluation by improving radiologists' sensitivity and specificity, as well as allowing localization of the lesion. Once the developing asymmetry has been fully characterized and localized with diagnostic mammography, targeted ultrasonography (US) should be performed to identify potentially benign causes of the developing asymmetry or identify a target for biopsy. However, lack of a US correlate should not preclude biopsy of a developing asymmetry. Diagnostic breast magnetic resonance imaging can be used in a minority of cases for problem solving or biopsy planning if no US correlate is identified and stereotactic biopsy is not feasible. The purpose of this article is to review the definition of developing asymmetry, describe the multimodality diagnostic tools available to the radiologist for evaluation of this challenging entity, and review the various causes, both benign and malignant.

Developing Asymmetry at Mammography: Correlation with US and MR Imaging and Histopathologic Findings.

PURPOSE: To evaluate ultrasonographic (US) and magnetic resonance (MR) imaging findings, histopathologic etiologies, and outcomes for developing asymmetry at mammography. MATERIALS AND METHODS: In this institutional review board-approved, informed consent-waived, HIPAA-compliant, retrospective review of a mammography database for records from January 1, 2009 to December 31, 2012, 2354 consecutive diagnostic mammograms classified as showing focal asymmetry were identified. After patients with benign results, those considered stable, and those without prior mammograms were excluded, images from 521 studies were reviewed and 202 developing lesions were identified in 201 women. Patient demographics, US and MR imaging findings, and clinical and histopathologic outcomes were obtained from the electronic medical records. Equivocal US correlates of findings with developing asymmetry detected at mammography were excluded from statistical analysis. The Fisher exact test and Student t test analysis were performed and relative risk and 95% confidence intervals (CIs) were determined. RESULTS: Biopsy was performed in 73 (36%) of 201 patients with developing asymmetries, with 42 (58%) benign and 31 (42%) malignant results. Of 128 patients with nonbiopsied lesions, 110 (86%) were stable at 24 months (considered benign), 12 (9.4%) were stable at less than 24 months, and six (4.7%) were lost to follow-up. Diagnostic US was performed in 186 (93%) of 201 patients, 74 (40%) with correlates. US was performed in 30 (97%) of 31 patients with malignant developing asymmetries, 17 (57%) with correlates, and in 140 (92%) of 152 patients with benign lesions, 51 (36%) with correlates (risk ratio, 1.92; 95% CI: 1.001, 3.695; two-tailed P = .064, one-tailed P = .038). MR imaging was performed in 66 (33%) of 201 patients, 26 (39%) with correlates. MR imaging was performed in 10 (32%) of 31 patients with malignant developing asymmetries, all with correlates, and 53 (35%) of 152 patients with benign lesions, 15 (28%) with correlates (P < .0001). CONCLUSION: Developing asymmetries were malignant in 15% (95% CI: 11%, 21.1%) of patients. Presence of a US or MR imaging correlate was predictive of malignancy.

A single-nucleotide polymorphism (-670) of the maternal Fas gene is associated with intrauterine growth restriction.

OBJECTIVE: We sought to determine whether the Fas (-670) single-nucleotide polymorphism is associated with intrauterine growth restriction. STUDY DESIGN: Twenty-seven pregnant women with intrauterine growth restriction in the absence of preeclampsia and 50 pregnant women with uncomplicated pregnancies were studied. DNA was extracted from maternal and infant buccal smears and allelic discrimination was performed for Fas (-670). Student t test, chi2, and z tests were used. RESULTS: There were no differences in maternal age, race, or parity between the intrauterine growth restriction and control patients. Mothers of intrauterine growth restriction infants had a significantly different genotype distribution for this single nucleotide polymorphism, and for the ratio of GG genotype (GG, AA: 0.41, 0.18 maternal intrauterine growth restriction; 0.14, 0.32 controls; respectively, P=.03). These genotype differences were significantly different in white, but not black mothers with intrauterine growth restriction (P=.03, and .3; respectively). In contrast, no differences were found in infants' Fas (-670) single-nucleotide polymorphism genotypes. CONCLUSION: This study demonstrates an association between the maternal Fas (-670) single-nucleotide polymorphism and the development of intrauterine growth restriction.

THM1 negatively modulates mouse sonic hedgehog signal transduction and affects retrograde intraflagellar transport in cilia.

Characterization of previously described intraflagellar transport (IFT) mouse mutants has led to the proposition that normal primary cilia are required for mammalian cells to respond to the sonic hedgehog (SHH) signal. Here we describe an N-ethyl-N-nitrosourea-induced mutant mouse, alien (aln), which has abnormal primary cilia and shows overactivation of the SHH pathway. The aln locus encodes a novel protein, THM1 (tetratricopeptide repeat-containing hedgehog modulator-1), which localizes to cilia. aln-mutant cilia have bulb-like structures at their tips in which IFT proteins (such as IFT88) are sequestered, characteristic of Chlamydomonas reinhardtii and Caenorhabditis elegans retrograde IFT mutants. RNA-interference knockdown of Ttc21b (which we call Thm1 and which encodes THM1) in mouse inner medullary collecting duct cells expressing an IFT88-enhanced yellow fluorescent protein fusion recapitulated the aln-mutant cilial phenotype, and live imaging of these cells revealed impaired retrograde IFT. In contrast to previously described IFT mutants, Smoothened and full-length glioblastoma (GLI) proteins localize to aln-mutant cilia. We hypothesize that the aln retrograde IFT defect causes sequestration of IFT proteins in aln-mutant cilia and leads to the overactivated SHH signaling phenotype. Specifically, the aln mutation uncouples the roles of anterograde and retrograde transport in SHH signaling, suggesting that anterograde IFT is required for GLI activation and that retrograde IFT modulates this event.