Hemorrhagic Complications Following Ultrasound-Guided Breast Biopsy: A Prospective Patient-Centered Study

OBJECTIVE

We aimed to evaluate the clinical and imaging factors associated with hemorrhagic complications and patient discomfort following ultrasound (US)-guided breast biopsy.

MATERIALS AND METHODS

We prospectively enrolled 94 patients who were referred to our hospital between June 2022 and December 2022 for US-guided breast biopsy. After obtaining informed consent, two breast radiologists independently performed US-guided breast biopsy and evaluated the imaging findings. A hemorrhagic complication was defined as the presence of bleeding or hematoma on US. The patients rated symptoms of pain, febrile sensation, swelling at the biopsy site, and dyspnea immediately, 20 minutes, and 2 weeks after the procedure on a visual analog scale, with 0 for none and 10 for the most severe symptoms. Additional details recorded included those of nausea, vomiting, bleeding, bruising, and overall satisfaction score. We compared the clinical symptoms, imaging characteristics, and procedural features between patients with and those without hemorrhagic complications.

RESULTS

Of 94 patients, 7 (7%) developed hemorrhagic complications, while 87 (93%) did not. The complication resolved with 20 minutes of manual compression, and no further intervention was required. Vascularity on Doppler examination (P = 0.008), needle type (P = 0.043), and lesion location (P < 0.001) were significantly different between the groups. Patients with hemorrhagic complications reported more frequent nausea or vomiting than those without hemorrhagic complications (29% [2/7] vs. 2% [2/87], respectively; P = 0.027). The overall satisfaction scores did not differ between the two groups (P = 0.396). After 2 weeks, all symptoms subsided, except bruising (50% 2/4 in the complication group and 25% [16/65] in the no-complication group).

CONCLUSION

US-guided breast biopsy is a safe procedure with a low complication rate. Radiologists should be aware of hemorrhagic complications, patient discomfort, and overall satisfaction related to this procedure.

Unenhanced Breast MRI With Diffusion-Weighted Imaging for Breast Cancer Detection: Effects of Training on Performance and Agreement of Subspecialty Radiologists

OBJECTIVE

To investigate whether reader training improves the performance and agreement of radiologists in interpreting unenhanced breast magnetic resonance imaging (MRI) scans using diffusion-weighted imaging (DWI).

MATERIALS AND METHODS

A study of 96 breasts (35 cancers, 24 benign, and 37 negative) in 48 asymptomatic women was performed between June 2019 and October 2020. High-resolution DWI with b-values of 0, 800, and 1200 sec/mm² was performed using a 3.0-T system. Sixteen breast radiologists independently reviewed the DWI, apparent diffusion coefficient maps, and T1-weighted MRI scans and recorded the Breast Imaging Reporting and Data System (BI-RADS) category for each breast. After a 2-h training session and a 5-month washout period, they re-evaluated the BI-RADS categories. A BI-RADS category of 4 (lesions with at least two suspicious criteria) or 5 (more than two suspicious criteria) was considered positive. The per-breast diagnostic performance of each reader was compared between the first and second reviews. Inter-reader agreement was evaluated using a multi-rater κ analysis and intraclass correlation coefficient (ICC).

RESULTS

Before training, the mean sensitivity, specificity, and accuracy of the 16 readers were 70.7% (95% confidence interval [CI]: 59.4-79.9), 90.8% (95% CI: 85.6-94.2), and 83.5% (95% CI: 78.6-87.4), respectively. After training, significant improvements in specificity (95.2%; 95% CI: 90.8-97.5; P = 0.001) and accuracy (85.9%; 95% CI: 80.9-89.8; P = 0.01) were observed, but no difference in sensitivity (69.8%; 95% CI: 58.1-79.4; P = 0.58) was observed. Regarding inter-reader agreement, the κ values were 0.57 (95% CI: 0.52-0.63) before training and 0.68 (95% CI: 0.62-0.74) after training, with a difference of 0.11 (95% CI: 0.02-0.18; P = 0.01). The ICC was 0.73 (95% CI: 0.69-0.74) before training and 0.79 (95% CI: 0.76-0.80) after training (P = 0.002).

CONCLUSION

Brief reader training improved the performance and agreement of interpretations by breast radiologists using unenhanced MRI with DWI.

Corrigendum: Diffusion-Weighted Magnetic Resonance Imaging for Preoperative Evaluation of Patients With Breast Cancer: Protocol of a Prospective, Multicenter, Observational Cohort Study

This corrects the article on p. 292 in vol. 26, PMID: 37272245.

Diffusion-Weighted Magnetic Resonance Imaging for Preoperative Evaluation of Patients With Breast Cancer: Protocol of a Prospective, Multicenter, Observational Cohort Study

PURPOSE

Detection of multifocal, multicentric, and contralateral breast cancers in patients affects surgical management. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) can identify additional foci that were initially undetected by conventional imaging. However, its use is limited owing to low specificity and high false-positive rate. Multiparametric MRI (DCE-MRI + diffusion-weighted [DW] MRI) can increase the specificity. We aimed to describe the protocols of our prospective, multicenter, observational cohort studies designed to compare the diagnostic performance of DCE-MRI and multiparametric MRI for the diagnosis of multifocal, multicentric cancer and contralateral breast cancer in patients with newly diagnosed breast cancer.

METHODS

Two studies comparing the performance of DCE-MRI and multiparametric MRI for the diagnosis of multifocal, multicentric cancer (NCT04656639) and contralateral breast cancer (NCT05307757) will be conducted. For trial NCT04656639, 580 females with invasive breast cancer candidates for breast conservation surgery whose DCE-MRI showed additional suspicious lesions (breast imaging reporting and data system [BI-RADS] category ≥ 4) on DCE-MRI in the ipsilateral breast will be enrolled. For trial NCT05307757, 1098 females with invasive breast cancer whose DCE-MRI showed contralateral lesions (BI-RADS category ≥ 3 or higher on DCE-MRI) will be enrolled. Participants will undergo 3.0-T DCE-MRI and DW-MRI. The diagnostic performance of DCE-MRI and multiparametric MRI will be compared. The receiver operating characteristic curve, sensitivity, specificity, positive predictive value, and characteristics of the detected cancers will be analyzed. The primary outcome is the difference in the receiver operating characteristic curve between DCE-MRI and multiparametric MRI interpretation. Enrollment completion is expected in 2024, and study results are expected to be presented in 2026.

DISCUSSION

This prospective, multicenter study will compare the performance of DCE-MRI versus multiparametric MRI for the preoperative evaluation of multifocal, multicentric, and contralateral breast cancer and is currently in the patient enrollment phase.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04656639, NCT05307757. Registered on April 1 2022.

Semiannual Breast US or MRI Screening in Patients with a Personal History of Breast Cancer

Background The wide variability of screening imaging use in patients with a personal history of breast cancer (PHBC) warrants investigation of its comparative clinical effectiveness. While more intensive screening with US or MRI at an interval of less than 1 year could increase early-stage breast cancer detection, its benefit has not been established. Purpose To investigate the outcomes of semiannual multimodality screening in patients with PHBC. Materials and Methods An academic medical center database was retrospectively searched for patients diagnosed with breast cancer between January 2015 and June 2018 who had undergone annual mammography with either semiannual incidence US or MRI screening from July 2019 to December 2019 and three subsequent semiannual screenings over a 2-year period. The primary outcome was second breast cancers diagnosed during follow-up. Examination-level cancer detection and interval cancer rates were calculated. Screening performances were compared with χ2 or Fisher exact tests or a logistic model with generalized estimating equations. Results Our final cohort included 2758 asymptomatic women (median age, 53 years; range, 20-84 years). Among 5615 US and 1807 MRI examinations, 18 breast cancers were detected after negative findings on a prior semiannual incidence US screening examination; 44% (eight of 18) were stage 0 (three detected with MRI; five, with US), and 39% (seven of 18) were stage I (three detected with MRI; four, with US). MRI had a cancer detection rate up to 17.1 per 1000 examinations (eight of 467; 95% CI: 8.7, 33.4), and the overall cancer detection rates of US and MRI were 1.8 (10 of 5615; 95% CI: 1.0, 3.3) and 4.4 (eight of 1807; 95% CI: 2.2, 8.8) per 1000 examinations, respectively (P = .11). Conclusion Supplemental semiannual US or MRI screening depicted second breast cancers after negative findings at prior semiannual incidence US examination in patients with PHBC. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Berg in this issue.

Use of imaging prediction model for omission of axillary surgery in early-stage breast cancer patients

PURPOSE

To develop a prediction model incorporating clinicopathological information, US, and MRI to diagnose axillary lymph node (LN) metastasis with acceptable false negative rate (FNR) in patients with early stage, clinically node-negative breast cancers.

METHODS

In this single center retrospective study, the inclusion criteria comprised women with clinical T1 or T2 and N0 breast cancers who underwent preoperative US and MRI between January 2017 and July 2018. Patients were temporally divided into the development and validation cohorts. Clinicopathological information, US, and MRI findings were collected. Two prediction models (US model and combined US and MRI model) were created using logistic regression analysis from the development cohort. FNRs of the two models were compared using the McNemar test.

RESULTS

A total of 964 women comprised the development (603 women, 54 ± 11 years) and validation (361 women, 53 ± 10 years) cohorts with 107 (18%) and 77 (21%) axillary LN metastases in each cohort, respectively. The US model consisted of tumor size and morphology of LN on US. The combined US and MRI model consisted of asymmetry of LN number, long diameter of LN, tumor type, and multiplicity of breast cancers on MRI, in addition to tumor size and morphology of LN on US. The combined model showed significantly lower FNR than the US model in both development (5% vs. 32%, P < .001) and validation (9% vs. 35%, P < .001) cohorts.

CONCLUSION

Our prediction model combining US and MRI characteristics of index cancer and LN lowered FNR compared to using US alone, and could potentially lead to avoid unnecessary SLNB in early stage, clinically node-negative breast cancers.

[Interpretation of Image-Guided Biopsy Results and Assessment]

The success of image-guided breast biopsy depends on the biopsy method, needle selection, and appropriate technique based on the accurate judgment by the radiologist at biopsy. However, insufficient or inappropriate sampling of specimens may result in false-negative results or pathologic underestimation. Therefore, image-pathology concordance assessments after biopsy are essential for appropriate patient management. Particularly, the assessment of image-pathology concordance can avoid false-negative reports of breast cancer as a benign pathology. Therefore, this study aimed to discuss factors that impact the accurate interpretation of image-guided breast biopsy along with the appropriate assessments.

Background Parenchymal Enhancement at Postoperative Surveillance Breast MRI: Association with Future Second Breast Cancer Risk

Background Background parenchymal enhancement (BPE) is a known risk factor for breast cancer. However, studies on the association between BPE and second breast cancer risk are still lacking. Purpose To investigate whether BPE at surveillance breast MRI is associated with subsequent second breast cancer risk in women with a personal history of breast cancer. Materials and Methods A retrospective search of the imaging database of an academic medical center identified consecutive surveillance breast MRI examinations performed between January 2008 and December 2017 in women who underwent surgery for primary breast cancer and had no prior diagnosis of second breast cancer. BPE at surveillance breast MRI was qualitatively assessed using a four-category classification of minimal, mild, moderate, or marked. Future second breast cancer was defined as ipsilateral breast tumor recurrence or contralateral breast cancer diagnosed at least 1 year after each surveillance breast MRI examination. Factors associated with future second breast cancer risk were evaluated using the multivariable Fine-Gray subdistribution hazard model. Results Among the 2668 women (mean age at baseline surveillance breast MRI, 49 years ± 8 [SD]), 109 developed a second breast cancer (49 ipsilateral, 58 contralateral, and two ipsilateral and contralateral) at a median follow-up of 5.8 years. Mild, moderate, or marked BPE at surveillance breast MRI (hazard ratio [HR], 2.1 [95% CI: 1.4, 3.1]; P < .001), young age (<45 years) at initial breast cancer diagnosis (HR, 3.4 [95% CI: 1.7, 6.4]; P < .001), positive results from a BRCA1/2 genetic test (HR, 6.5 [95% CI: 3.5, 12.0]; P < .001), and negative hormone receptor expression in the initial breast cancer (HR, 1.6 [95% CI: 1.1, 2.6]; P = .02) were independently associated with an increased risk of future second breast cancer. Conclusion Background parenchymal enhancement at surveillance breast MRI was associated with future second breast cancer risk in women with a personal history of breast cancer. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Niell in this issue.

Digital Breast Tomosynthesis Plus Ultrasound Versus Digital Mammography Plus Ultrasound for Screening Breast Cancer in Women With Dense Breasts

OBJECTIVE

To compare the outcomes of digital breast tomosynthesis (DBT) screening combined with ultrasound (US) with those of digital mammography (DM) combined with US in women with dense breasts.

MATERIALS AND METHODS

A retrospective database search identified consecutive asymptomatic women with dense breasts who underwent breast cancer screening with DBT or DM and whole-breast US simultaneously between June 2016 and July 2019. Women who underwent DBT + US (DBT cohort) and DM + US (DM cohort) were matched using 1:2 ratio according to mammographic density, age, menopausal status, hormone replacement therapy, and a family history of breast cancer. The cancer detection rate (CDR) per 1000 screening examinations, abnormal interpretation rate (AIR), sensitivity, and specificity were compared.

RESULTS

A total of 863 women in the DBT cohort were matched with 1726 women in the DM cohort (median age, 53 years; interquartile range, 40-78 years) and 26 breast cancers (9 in the DBT cohort and 17 in the DM cohort) were identified. The DBT and DM cohorts showed comparable CDR (10.4 [9 of 863; 95% confidence interval {CI}: 4.8-19.7] vs. 9.8 [17 of 1726; 95% CI: 5.7-15.7] per 1000 examinations, respectively; P = 0.889). DBT cohort showed a higher AIR than the DM cohort (31.6% [273 of 863; 95% CI: 28.5%-34.9%] vs. 22.4% [387 of 1726; 95% CI: 20.5%-24.5%]; P < 0.001). The sensitivity for both cohorts was 100%. In women with negative findings on DBT or DM, supplemental US yielded similar CDRs in both DBT and DM cohorts (4.0 vs. 3.3 per 1000 examinations, respectively; P = 0.803) and higher AIR in the DBT cohort (24.8% [188 of 758; 95% CI: 21.8%-28.0%] vs. 16.9% [257 of 1516; 95% CI: 15.1%-18.9%; P < 0.001).

CONCLUSION

DBT screening combined with US showed comparable CDR but lower specificity than DM screening combined with US in women with dense breasts.

Use of Artificial Intelligence for Reducing Unnecessary Recalls at Screening Mammography: A Simulation Study

OBJECTIVE

To conduct a simulation study to determine whether artificial intelligence (AI)-aided mammography reading can reduce unnecessary recalls while maintaining cancer detection ability in women recalled after mammography screening.

MATERIALS AND METHODS

A retrospective reader study was performed by screening mammographies of 793 women (mean age ± standard deviation, 50 ± 9 years) recalled to obtain supplemental mammographic views regarding screening mammography-detected abnormalities between January 2016 and December 2019 at two screening centers. Initial screening mammography examinations were interpreted by three dedicated breast radiologists sequentially, case by case, with and without AI aid, in a single session. The area under the receiver operating characteristic curve (AUC), sensitivity, specificity, and recall rate for breast cancer diagnosis were obtained and compared between the two reading modes.

RESULTS

Fifty-four mammograms with cancer (35 invasive cancers and 19 ductal carcinomas in situ) and 739 mammograms with benign or negative findings were included. The reader-averaged AUC improved after AI aid, from 0.79 (95% confidence interval [CI], 0.74-0.85) to 0.89 (95% CI, 0.85-0.94) (p < 0.001). The reader-averaged specificities before and after AI aid were 41.9% (95% CI, 39.3%-44.5%) and 53.9% (95% CI, 50.9%-56.9%), respectively (p < 0.001). The reader-averaged sensitivity was not statistically different between AI-unaided and AI-aided readings: 89.5% (95% CI, 83.1%-95.9%) vs. 92.6% (95% CI, 86.2%-99.0%) (p = 0.053), although the sensitivities of the least experienced radiologists before and after AI aid were 79.6% (43 of 54 [95% CI, 66.5%-89.4%]) and 90.7% (49 of 54 [95% CI, 79.7%-96.9%]), respectively (p = 0.031). With AI aid, the reader-averaged recall rate decreased by from 60.4% (95% CI, 57.8%-62.9%) to 49.5% (95% CI, 46.5%-52.4%) (p < 0.001).

CONCLUSION

AI-aided reading reduced the number of recalls and improved the diagnostic performance in our simulation using women initially recalled for supplemental mammographic views after mammography screening.

Ginsenoside Rg-1 prevents elevated cytosolic Ca2+ via store-operated Ca2+ entry in high-glucose–stimulated vascular endothelial and smooth muscle cells

Background

Ginsenoside Rg-1 (Rg-1), a triterpenoid saponin abundantly present in Panax ginseng, is a type of naturally occurring steroid with known anti-diabetic and anti-inflammatory effects. In this study, we sought to confirm the effects and mechanisms of action of Rg-1 on store-operated Ca²⁺ entry (SOCE) in human vascular endothelial cell line (EA) and murine aortic vascular smooth muscle cell line (MOVAS) cells exposed to high glucose.

Methods

Cytosolic Ca²⁺ concentrations in EA and MOVAS cells were measured by monitoring fluorescence of the ratiometric Ca²⁺-indicator, Fura-2 AM.

Results

High glucose significantly increased Ca²⁺ influx by abnormally activating SOCE in EA and MOVAS cells. Notably, this high glucose-induced increase in SOCE was restored to normal levels in EA and MOVAS cells by Rg-1. Moreover, Rg-1 induced reductions in SOCE in cells exposed to high glucose were significantly inhibited by the plasma membrane Ca²⁺ ATPase (PMCA) blocker lanthanum, the Na⁺/K⁺-ATPase blocker ouabain, or the Na⁺/Ca²⁺ exchanger (NCX) blockers Ni²⁺ and KB-R7943. These observations suggest that the mechanism of action of Rg-1 inhibition of SOCE involves PMCA and Na⁺/K⁺-ATPase, and an increase in Ca²⁺ efflux via NCXs in both EA and MOVAS cells exposed to high glucose.

Conclusions

These findings indicate that Rg-1 may protect vascular endothelial and smooth muscle cells from Ca²⁺ increases following exposure to hyperglycemic conditions.

US Evaluation of Axillary Lymphadenopathy Following COVID-19 Vaccination: A Prospective Longitudinal Study

Background Both temporal changes in imaging characteristics of lymphadenopathy on US scans after COVID-19 vaccination and expected duration of radiologically evident lymphadenopathy remain uncertain. Purpose To longitudinally evaluate COVID-19 vaccine-associated lymphadenopathy on axillary US scans at various time intervals in both messenger (mRNA) and vector vaccine recipients. Materials and Methods This prospective cohort study was conducted between March 2021 and January 2022. The participants were asymptomatic women without breast cancer who had received COVID-19 vaccination. Serial follow-up US was performed in women with lymphadenopathy. The following variables were assessed: cortical thickness, number of lymph nodes, morphologic characteristics, and Doppler signal. Temporal changes in cortical thickness and number of lymph nodes during follow-up were assessed using a linear mixed model. Results Ninety-one women with lymphadenopathy in the vaccinated arm had undergone a total of 215 serial US examinations (mean age, 44 years ± 13 [SD]). Fifty-one participants had received a vector vaccine (ChAdOx1 nCoV-19 vaccine) and 40 had received an mRNA vaccine (BNT162b2 vaccine [n = 37] and mRNA-1273 vaccine [n = 3]). Three of the 91 women were lost to follow-up; thus, 88 women underwent serial US. Complete resolution of axillary lymphadenopathy was observed at a median of 6 weeks after vaccination (range, 4-7 weeks) in 26% of women (23 of 88). Among 49 women with follow-up US at a median of 12 weeks after vaccination (range, 8-14 weeks), persistent lymphadenopathy was observed in 25 (51%). During the follow-up period, the cortical thickness gradually decreased (P < .001) over time regardless of vaccine type; however, values were higher in recipients of the mRNA vaccine than in recipients of the vector vaccine (P = .02). Conclusion COVID-19 vaccine-associated axillary lymphadenopathy frequently persisted for more than 6 weeks on US scans. Lymphadenopathy should be interpreted considering vaccine type and time elapsed since vaccination. Follow-up US examination at least 12 weeks after vaccination may be reasonable, particularly for recipients of the messenger RNA vaccine. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Moy and Kim in this issue.

Abbreviated Screening MRI for Women with a History of Breast Cancer: Comparison with Full-Protocol Breast MRI

Background Few studies have compared abbreviated breast MRI with full-protocol MRI in women with a personal history of breast cancer (PHBC), and they have not adjusted for confounding variables. Purpose To compare abbreviated breast MRI with full-protocol MRI in women with PHBC by using propensity score matching to adjust for confounding variables. Materials and Methods In this single-center retrospective study, women with PHBC who underwent full-protocol MRI (January 2008-August 2017) or abbreviated MRI (September 2017-April 2019) were identified. With use of a propensity score-matched cohort, screening performances were compared between the two MRI groups with the McNemar test or a propensity score-adjusted generalized estimating equation. The coprimary analyses were sensitivity and specificity. The secondary analyses were the cancer detection rate, interval cancer rate, positive predictive value for biopsies performed (PPV3), and Breast Imaging Reporting and Data System (BI-RADS) category 3 short-term follow-up rate. Results There were 726 women allocated to each MRI group (mean age ± SD, 50 years ± 8 for both groups). Abbreviated MRI and full-protocol MRI showed comparable sensitivity (15 of 15 cancers [100%; 95% CI: 78, 100] vs nine of 13 cancers [69%; 95% CI: 39, 91], respectively; P = .17). Abbreviated MRI showed higher specificity than full-protocol MRI (660 of 711 examinations [93%; 95% CI: 91, 95] vs 612 of 713 examinations [86%; 95% CI: 83, 88], respectively; P < .001). The cancer detection rate (21 vs 12 per 1000 examinations), interval cancer rate (0 vs five per 1000 examinations), and PPV3 (61% [14 of 23 examinations] vs 41% [nine of 22 examinations]) were comparable (all P < .05). The BI-RADS category 3 short-term follow-up rate of abbreviated MRI was less than half that of full-protocol MRI (5% [36 of 726 examinations] vs 12% [84 of 726 examinations], respectively; P < .001). Ninety-three percent (14 of 15) of cancers detected at abbreviated MRI were node-negative T1-invasive cancers (n = 6) or ductal carcinoma in situ (n = 8). Conclusion Abbreviated breast MRI showed comparable sensitivity and superior specificity to full-protocol MRI in breast cancer detection in women with a personal history of breast cancer. © RSNA, 2022 Online supplemental material is available for this article.

Microcalcifications and Peritumoral Edema Predict Survival Outcome in Luminal Breast Cancer Treated with Neoadjuvant Chemotherapy

Background Little is known regarding findings at imaging associated with survival in patients with luminal breast cancer treated with neoadjuvant chemotherapy (NAC). Purpose To determine the relationship between imaging (MRI, US, and mammography) and clinical-pathologic variables in predicting distant metastasis-free survival (DMFS) and overall survival (OS) in patients with luminal breast cancer treated with NAC. Materials and Methods In this retrospective study, consecutive women with luminal breast cancer who underwent NAC followed by surgery were identified from the breast cancer registries of two hospitals. Women from one hospital between January 2003 and July 2015 were classified into the development cohort, and women from the other hospital between January 2007 and July 2015 were classified into the validation cohort. MRI scans, US scans, and mammograms before and after NAC (hereafter, referred to as pre- and post-NAC, respectively) and clinical-pathologic data were reviewed. Peritumoral edema was defined as the water-like high signal intensity surrounding the tumor on T2-weighted MRI scans. The prediction model was developed in the development cohort by using Cox regression and then tested in the validation cohort. Results The development cohort consisted of 318 women (68 distant metastases, 54 deaths) and the validation cohort consisted of 165 women (37 distant metastases, 14 deaths) (median age, 46 years in both cohorts). Post-NAC MRI peritumoral edema, age younger than 40 years, clinical N2 or N3, and lymphovascular invasion were associated with worse DMFS (all, P < .05). Pre-NAC mammographic microcalcifications, post-NAC MRI peritumoral edema, age older than 60 years, and clinical T3 or T4 were associated with worse OS (all, P < .05). The prediction model showed good discrimination ability (C index, 0.67-0.75 for DMFS and 0.70-0.77 for OS) and stratified prognosis into low-risk and high-risk groups (10-year DMFS rates, 79% vs 21%, respectively; and 10-year OS rates, 95%-96% vs 63%-67%, respectively) in the validation cohort. Conclusion MRI features and clinical-pathologic variables were identified that were associated with prolonged survival of patients with luminal breast cancer treated with neoadjuvant chemotherapy. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Kataoka in this issue.

Quantitative analysis of vascularity for thyroid nodules on ultrasound using superb microvascular imaging: Can nodular vascularity differentiate between malignant and benign thyroid nodules?

This study aimed to investigate the utility of adding superb microvascular imaging (SMI) to B-mode ultrasound (US) for distinguishing between benign and malignant thyroid nodules and evaluate the usefulness of SMI quantification of nodular vascularity for diagnosing thyroid cancer.The malignancy likelihood was scored for 3 datasets before versus after additional color Doppler imaging or SMI using 4-scale visual analysis (i.e., B-mode US alone, B-mode US + color Doppler image, and B-mode US + SMI). Further, the SMI pixel count was measured in the region of interest, including the whole nodule, on the longitudinal view. It was compared between benign and malignant nodules and analyzed according to the US patterns of thyroid nodules based on the Korean thyroid imaging reporting and data system. We calculated the area under the receiver operating characteristic curve values, sensitivities, and specificities.There was no significant difference in the area under the receiver operating characteristic curve values among B-mode, B-mode + color Doppler, and B-mode + SMI. However, the SMI pixel count was significantly higher in malignant thyroid nodules than in benign ones. The optimal cut-off value for the SMI pixel count for predicting malignant thyroid nodules obtained using a receiver operating characteristic curve was 17 (40.54% in sensitivity, 91.3% in specificity). Analysis based on the US pattern of thyroid nodules revealed significant differences in the nodules with low-to-intermediate suspicious US features between malignant and benign nodules.Quantification analysis of vascularity using SMI can differentiate malignant thyroid nodules from benign ones.

Diagnostic performance improvement with combined use of proteomics biomarker assay and breast ultrasound

PURPOSE

To investigate the combined use of blood-based 3-protein signature and breast ultrasound (US) for validating US-detected lesions.

METHODS

From July 2011 to April 2020, women who underwent whole-breast US within at least 6 months from sampling period were retrospectively included. Blood-based 3-protein signature (Mastocheck®) value and US findings were evaluated. Following outcome measures were compared between US alone and the combination of Mastocheck® value with US: sensitivity, specificity, positive predictive value (PPV), negative predictive value, area under the receiver operating characteristic curve (AUC), and biopsy rate.

RESULTS

Among the 237 women included, 59 (24.9%) were healthy individuals and 178 (75.1%) cancer patients. Mean size of cancers was 1.2 ± 0.8 cm. Median value of Mastocheck® was significantly different between nonmalignant (- 0.24, interquartile range [IQR] - 0.48, - 0.03) and malignant lesions (0.55, IQR - 0.03, 1.42) (P < .001). Utilizing Mastocheck® value with US increased the AUC from 0.67 (95% confidence interval [CI] 0.61, 0.73) to 0.81 (95% CI 0.75, 0.88; P < .001), and specificity from 35.6 (95% CI 23.4, 47.8) to 64.4% (95% CI 52.2, 76.6; P < .001) without loss in sensitivity. PPV was increased from 82.2 (95% CI 77.1, 87.3) to 89.3% (95% CI 85.0, 93.6; P < .001), and biopsy rate was significantly decreased from 79.3 (188/237) to 72.1% (171/237) (P < .001). Consistent improvements in specificity, PPV, and AUC were observed in asymptomatic women, in women with dense breast, and in those with normal/benign mammographic findings.

CONCLUSION

Mastocheck® is an effective tool that can be used with US to improve diagnostic specificity and reduce false-positive findings and unnecessary biopsies.

Radiation Dose Reduction in Digital Mammography by Deep-Learning Algorithm Image Reconstruction: A Preliminary Study

Purpose

To develop a denoising convolutional neural network-based image processing technique and investigate its efficacy in diagnosing breast cancer using low-dose mammography imaging.

Materials and Methods

A total of 6 breast radiologists were included in this prospective study. All radiologists independently evaluated low-dose images for lesion detection and rated them for diagnostic quality using a qualitative scale. After application of the denoising network, the same radiologists evaluated lesion detectability and image quality. For clinical application, a consensus on lesion type and localization on preoperative mammographic examinations of breast cancer patients was reached after discussion. Thereafter, coded low-dose, reconstructed full-dose, and full-dose images were presented and assessed in a random order.

Results

Lesions on 40% reconstructed full-dose images were better perceived when compared with low-dose images of mastectomy specimens as a reference. In clinical application, as compared to 40% reconstructed images, higher values were given on full-dose images for resolution (p < 0.001); diagnostic quality for calcifications (p < 0.001); and for masses, asymmetry, or architectural distortion (p = 0.037). The 40% reconstructed images showed comparable values to 100% full-dose images for overall quality (p = 0.547), lesion visibility (p = 0.120), and contrast (p = 0.083), without significant differences.

Conclusion

Effective denoising and image reconstruction processing techniques can enable breast cancer diagnosis with substantial radiation dose reduction.

Precautions for breast ultrasound examination following COVID-19 vaccination

Background: Coronavirus disease 2019 (COVID-19) vaccine-induced lymphadenopathy is a critical side effect that should be a concern to clinicians, patients, radiologists, and oncologists. Vaccine-induced lymphadenopathy causes a diagnostic dilemma, especially for breast radiologists who examine both axillary regions during breast ultrasound examinations. Appropriate imaging guidelines are needed to manage vaccine-induced lymphadenopathy for patients undergoing screening examinations or symptomatic patients, including cancer patients.Current Concepts: For patients with axillary lymphadenopathy in the setting of recent ipsilateral vaccination, clinical follow-up is recommended. In other scenarios, short-term follow-up axillary ultrasound examinations are recommended if the clinical concerns persist for more than 6 weeks after vaccination. To mitigate the diagnostic dilemma of vaccine-induced lymphadenopathy, patients should schedule screening imaging examinations before the first vaccination or at least six weeks following the second vaccination. For clinicians and radiologists, documenting the patients’ vaccination status is critical to decreasing unnecessary follow-up imaging, biopsies, and patient’s anxiety.Discussion and Conclusion: Our proposal can help reduce patient anxiety, provider burden, and costs of unnecessary evaluation of enlarged lymph nodes in the setting of recent COVID-19 vaccination. Further, it can avoid delays in vaccination and breast cancer screening during the COVID-19 pandemic.

Glandular Tissue Component and Breast Cancer Risk in Mammographically Dense Breasts at Screening Breast US

Background Breast density at mammography is an established risk factor for breast cancer, but it cannot be used to distinguish between glandular and fibrous tissue. Purpose To evaluate the association between the glandular tissue component (GTC) at screening breast US and the risk of future breast cancer in women with dense breasts and the association between the GTC and lobular involution. Materials and Methods Screening breast US examinations performed in women with no prior history of breast cancer and with dense breasts with negative findings from mammography from January 2012 to December 2015 were retrospectively identified. The GTC was reported as being minimal, mild, moderate, or marked at the time of the US examination. In women who had benign breast biopsy results, the degree of lobular involution in normal background tissue was categorized as not present, mild, moderate, or complete. The GTC-related breast cancer risk in women with a cancer diagnosis or follow-up after 6 months was estimated by using Cox proportional hazards regression. Cumulative logistic regression was used to evaluate the association between the GTC and lobular involution. Results Among 8483 women (mean age, 49 years ± 8 [standard deviation]), 137 developed breast cancer over a median follow-up time of 5.3 years. Compared with a minimal or mild GTC, a moderate or marked GTC was associated with an increased cancer risk (hazard ratio, 1.5; 95% CI: 1.05, 2.1; P = .03) after adjusting for age and breast density. The GTC had an inverse association with lobular involution; women with no, mild, or moderate involution had greater odds (odds ratios of 4.9 [95% CI: 1.5, 16.6], 2.6 [95% CI: 0.95, 7.2], and 1.8 [95% CI: 0.7, 4.6], respectively) of a moderate or marked GTC than those with complete involution (P = .004). Conclusion The glandular tissue component was independently associated with the future breast cancer risk in women with dense breasts and reflects the lobular involution. It should be considered for risk stratification during screening breast US. © RSNA, 2021 Online supplemental material is available for this article.

Noncontrast-Enhanced MR-Based Conductivity Imaging for Breast Cancer Detection and Lesion Differentiation

BACKGROUND

There is increasing interest in noncontrast-enhanced MRI due to safety concerns for gadolinium contrast agents.

PURPOSE

To investigate the clinical feasibility of MR-based conductivity imaging for breast cancer detection and lesion differentiation.

STUDY TYPE

Prospective.

SUBJECTS

One hundred and ten women, with 112 known cancers and 17 benign lesions (biopsy-proven), scheduled for preoperative MRI.

FIELD STRENGTH/SEQUENCE

Non-fat-suppressed T2-weighted turbo spin-echo sequence (T2WI), dynamic contrast-enhanced MRI and diffusion-weighted imaging (DWI) at 3T.

ASSESSMENT

Cancer detectability on each imaging modality was qualitatively evaluated on a per-breast basis: the conductivity maps derived from T2WI were independently reviewed by three radiologists (R1-R3). T2WI, DWI, and pre-operative digital mammography were independently reviewed by three other radiologists (R4-R6). Conductivity and apparent diffusion coefficient (ADC) measurements (mean, minimum, and maximum) were performed for 112 cancers and 17 benign lesions independently by two radiologists (R1 and R2). Tumor size was measured from surgical specimens.

STATISTICAL TESTS

Cancer detection rates were compared using generalized estimating equations. Multivariable logistic regression analysis was performed to identify factors associated with cancer detectability. Discriminating ability of conductivity and ADC was evaluated by using the areas under the receiver operating characteristic curve (AUC).

RESULTS

Conductivity imaging showed lower cancer detection rates (20%-32%) compared to T2WI (62%-71%), DWI (85%-90%), and mammography (79%-88%) (all P < 0.05). Fatty breast on MRI (odds ratio = 11.8, P < 0.05) and invasive tumor size (odds ratio = 1.7, P < 0.05) were associated with cancer detectability of conductivity imaging. The maximum conductivity showed comparable ability to the mean ADC in discriminating between cancers and benign lesions (AUC = 0.67 [95% CI: 0.59, 0.75] vs. 0.84 [0.76, 0.90], P = 0.06 (R1); 0.65 [0.56, 0.73] vs. 0.82 [0.74, 0.88], P = 0.07 (R2)).

DATA CONCLUSION

Although conductivity imaging showed suboptimal performance in breast cancer detection, the quantitative measurement of conductivity showed the potential for lesion differentiation.

EVIDENCE LEVEL

1 TECHNICAL EFFICACY: Stage 2.

Detection of Contralateral Breast Cancer Using Diffusion-Weighted Magnetic Resonance Imaging in Women with Newly Diagnosed Breast Cancer: Comparison with Combined Mammography and Whole-Breast Ultrasound

Objective

To compare the screening performance of diffusion-weighted (DW) MRI and combined mammography and ultrasound (US) in detecting clinically occult contralateral breast cancer in women with newly diagnosed breast cancer.

Materials and Methods

Between January 2017 and July 2018, 1148 women (mean age ± standard deviation, 53.2 ± 10.8 years) with unilateral breast cancer and no clinical abnormalities in the contralateral breast underwent 3T MRI, digital mammography, and radiologist-performed whole-breast US. In this retrospective study, three radiologists independently and blindly reviewed all DW MR images (b = 1000 s/mm² and apparent diffusion coefficient map) of the contralateral breast and assigned a Breast Imaging Reporting and Data System category. For combined mammography and US evaluation, prospectively assessed results were used. Using histopathology or 1-year follow-up as the reference standard, cancer detection rate and the patient percentage with cancers detected among all women recommended for tissue diagnosis (positive predictive value; PPV₂) were compared.

Results

Of the 30 cases of clinically occult contralateral cancers (13 invasive and 17 ductal carcinoma in situ [DCIS]), DW MRI detected 23 (76.7%) cases (11 invasive and 12 DCIS), whereas combined mammography and US detected 12 (40.0%, five invasive and seven DCIS) cases. All cancers detected by combined mammography and US, except two DCIS cases, were detected by DW MRI. The cancer detection rate of DW MRI (2.0%; 95% confidence interval [CI]: 1.3%, 3.0%) was higher than that of combined mammography and US (1.0%; 95% CI: 0.5%, 1.8%; p = 0.009). DW MRI showed higher PPV₂ (42.1%; 95% CI: 26.3%, 59.2%) than combined mammography and US (18.5%; 95% CI: 9.9%, 30.0%; p = 0.001).

Conclusion

In women with newly diagnosed breast cancer, DW MRI detected significantly more contralateral breast cancers with fewer biopsy recommendations than combined mammography and US.

Factors Affecting Pathologic Complete Response Following Neoadjuvant Chemotherapy in Breast Cancer: Development and Validation of a Predictive Nomogram

Background There is an increasing need to develop a more accurate prediction model for pathologic complete response (pCR) after neoadjuvant chemotherapy (NAC) in breast cancer. Purpose To develop a nomogram based on MRI and clinical-pathologic variables to predict pCR. Materials and Methods In this single-center retrospective study, consecutive women with stage II-III breast cancer who underwent NAC followed by surgery between January 2011 and December 2017 were considered for inclusion. The women were divided into a development cohort between January 2011 and September 2015 and a validation cohort between October 2015 and December 2017. Clinical-pathologic data were collected, and mammograms and MRI scans obtained before and after NAC were analyzed. Logistic regression analyses were performed to identify independent variables associated with pCR in the development cohort from which the nomogram was created. Nomogram performance was assessed with the area under the receiver operating characteristic curve (AUC) and calibration slope. Results A total of 359 women (mean age, 49 years ± 10 [standard deviation]) were in the development cohort and 351 (49 years ± 10) in the validation cohort. Hormone receptor negativity (odds ratio [OR], 3.1; 95% CI: 1.4, 7.1; P = .006), high Ki-67 index (OR, 1.05; 95% CI: 1.03, 1.07; P < .001), and post-NAC MRI variables, including small tumor size (OR, 0.6; 95% CI: 0.4, 0.9; P = .03), low lesion-to-background parenchymal signal enhancement ratio (OR, 0.2; 95% CI: 0.1, 0.6; P = .004), and absence of enhancement in the tumor bed (OR, 3.8; 95% CI: 1.4, 10.5; P = .009) were independently associated with pCR. The nomogram incorporating these variables showed good discrimination (AUC, 0.90; 95% CI: 0.86, 0.94) and calibration abilities (calibration slope, 0.91; 95% CI: 0.69, 1.13) in the independent validation cohort. Conclusion A nomogram incorporating hormone receptor status, Ki-67 index, and MRI variables showed good discrimination and calibration abilities in predicting pathologic complete response. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Imbriaco and Ponsiglione in this issue.

A preliminary study of the combination of ultrafast and abbreviated dynamic contrast: Enhanced breast magnetic resonance imaging

We combined the abbreviated and ultrafast magnetic resonance imaging (MRI) technique with the standard MRI protocol and compared lesion characterization quantitatively and qualitatively to the standard MRI protocol.Fifty-six patients with breast cancer who underwent MRI from June 2017 to May 2018 and fulfilled our inclusion criteria were included. Three radiologists measured the lesion sizes, described the MRI findings using BI-RADS lexicon, and demarcated the regions of interest to extract the volumetric quantitative and semi-quantitative parameters. We used Pearson's correlation analysis comparing the quantitative and semi-quantitative parameters. To evaluate the inter-observer variability, we calculated the intra-correlation coefficient (ICC). We also analysed the correlation in BI-RADS lexicon.There were 45 (80.4%) luminal and 11 (19.6%) non-luminal breast cancers, and the most common tumour subtype was invasive carcinoma (n = 48, 85.7%), followed by ductal carcinoma in situ (n = 8, 14.3%). Regarding correlation between the quantitative and semi-quantitative parameters, K significantly correlated with the wash-in factor (r, 0.862; P < .001) and AUC value (r, 0.951; P < .001). The lesion size measured by standard and combined abbreviated-ultrafast phases and that from the surgical pathological specimens showed moderate agreement (ICC range, 0.516-0.578). The ICCs among the 3 readers were excellent for lesion size measurement, BI-RADS lexicon regarding lesion type, mass shape, margin, internal enhancement, non-mass enhancement distribution, and internal enhancement by the standard and combined abbreviated-ultrafast protocols.The use of the modified and combined abbreviated-ultrafast MRI protocol provides a reliable measurement of the quantitative parameters and may aid in the screening of breast cancer.

Comparison of Abbreviated MRI and Full Diagnostic MRI in Distinguishing between Benign and Malignant Lesions Detected by Breast MRI: A Multireader Study

Objective

To compare the performance of simulated abbreviated breast MRI (AB-MRI) and full diagnostic (FD)-MRI in distinguishing between benign and malignant lesions detected by MRI and investigate the features of discrepant lesions of the two protocols.

Materials and Methods

An AB-MRI set with single first postcontrast images was retrospectively obtained from an FD-MRI cohort of 111 lesions (34 malignant, 77 benign) detected by contralateral breast MRI in 111 women (mean age, 49.8. ± 9.8; range, 28–75 years) with recently diagnosed breast cancer. Five blinded readers independently classified the likelihood of malignancy using Breast Imaging Reporting and Data System assessments. McNemar tests and area under the receiver operating characteristic curve (AUC) analyses were performed. The imaging and pathologic features of the discrepant lesions of the two protocols were analyzed.

Results

The sensitivity of AB-MRI for lesion characterization tended to be lower than that of FD-MRI for all readers (58.8–82.4% vs. 79.4–100%), although the findings of only two readers were significantly different (p < 0.05). The specificity of AB-MRI for lesion characterization was higher than that of FD-MRI for 80% of readers (39.0–74.0% vs. 19.5–45.5%, p ≤ 0.001). The AUC of AB-MRI was comparable to that of FD-MRI for all readers (p > 0.05). Fifteen percent (5/34) of the cancers were false-negatives on AB-MRI. More suspicious margins or internal enhancement on the delayed phase images were related to the discrepancies.

Conclusion

The overall performance of AB-MRI was similar to that of FD-MRI in distinguishing between benign and malignant lesions. AB-MRI showed lower sensitivity and higher specificity than FD-MRI, as 15% of the cancers were misclassified compared to FD-MRI.

Diffusion-weighted MRI at 3.0 T for detection of occult disease in the contralateral breast in women with newly diagnosed breast cancer

PURPOSE

Diffusion-weighted magnetic resonance imaging (DW-MRI) offers unenhanced method to detect breast cancer without cost and safety concerns associated with dynamic contrast-enhanced (DCE) MRI. Our purpose was to evaluate the performance of DW-MRI at 3.0T in detection of clinically and mammographically occult contralateral breast cancer in patients with unilateral breast cancer.

METHODS

Between 2017 and 2018, 1130 patients (mean age 53.3 years; range 26-84 years) with newly diagnosed unilateral breast cancer who underwent breast MRI and had no abnormalities on clinical and mammographic examinations of contralateral breast were included. Three experienced radiologists independently reviewed DW-MRI (b = 0 and 1000 s/mm²) and DCE-MRI and assigned a BI-RADS category. Using histopathology or 1-year clinical follow-up, performance measures of DW-MRI were compared with DCE-MRI.

RESULTS

A total of 21 (1.9%, 21/1130) cancers were identified (12 ductal carcinoma in situ and 9 invasive ductal carcinoma; mean invasive tumor size, 8.0 mm) in the contralateral breast. Cancer detection rate of DW-MRI was 13-15 with mean of 14 per 1000 examinations (95% confidence interval [CI] 9-23 per 1000 examinations), which was lower than that of DCE-MRI (18-19 with mean of 18 per 1000 examinations, P = 0.01). A lower abnormal interpretation rate (14.0% versus 17.0%, respectively, P < 0.001) with higher specificity (87.3% versus 84.6%, respectively, P < 0.001) but lower sensitivity (77.8% versus 96.8%, respectively, P < 0.001) was noted for DW-MRI compared to DCE-MRI.

CONCLUSIONS

DW-MRI at 3.0T has the potential as a cost-effective tool for evaluation of contralateral breast in women with newly diagnosed breast cancer.

Assessing the diagnostic performance of thyroid biopsy with recommendations for appropriate interpretation

Purpose

The diagnostic performance of thyroid biopsy is influenced by several factors, including differences in the Bethesda categorization for malignancy, the inclusion or exclusion of non-diagnostic results, the definition used for the final diagnosis, and the definition of an inconclusive diagnosis. The purpose of this study was to provide an understanding of the factors influencing the diagnostic performance of thyroid biopsy.

Methods

We collected data retrospectively between January and December 2013 from a cohort of 6,762 thyroid nodules from 6,493 consecutive patients who underwent biopsy. In total, 4,822 nodules from 4,553 patients were included. We calculated the biopsy sensitivity according to the inclusion of different Bethesda categories in the numerator and the exclusion of non-diagnostic results, as well as the diagnostic accuracy according to different definitions of a benign diagnosis. We obtained the conclusive and inconclusive diagnosis rates.

Results

The sensitivity increased when more Bethesda categories were included in the numerator and when non-diagnostic results were excluded. When a benign thyroid nodule diagnosis was defined as benign findings on surgical resection, concordant benign results on at least two occasions, or an initial benign biopsy result and follow-up for more than 12 months, the accuracy was higher than when the diagnosis was based on surgical resection alone (91.1% vs. 68.7%). A higher conclusive diagnosis rate was obtained when Bethesda categories I and III were considered inconclusive than when Bethesda categories I, III and IV were considered inconclusive (78.3% vs. 72.8%, P<0.001).

Conclusion

Understanding the concepts presented herein is important in order to appropriately interpret the diagnostic performance of thyroid biopsy.

Diagnostic performance of standard breast MR imaging compared to dedicated axillary MR imaging in the evaluation of axillary lymph node

BACKGROUND

Breast magnetic resonance (MR) imaging does not usually assess axillary lymph nodes -using dedicated axillary sequence. The additional utility of dedicated axillary sequence is poorly understood. We evaluated the diagnostic performance of dedicated axillary imaging sequence for evaluation of axillary lymph node.

METHODS

In this retrospective study from January 2018 to March 2018, 750 consecutive women underwent breast MR imaging. 263 patients were excluded, due to neoadjuvant chemotherapy (n = 235), incomplete histopathological information (n = 14) and follow-up loss (n = 14), 487 women were included. Two radiologists scored lymph node on confidence level scale from 0 (definitely benign) to 4 (definitely malignant), -using standard MR and dedicated axillary imaging sequences. Diagnostic performance parameters were compared and calculated correlation coefficient of quantitative features (largest dimension, cortical thickness, and the ratio of cortical thickness to largest dimension of lymph node).

RESULTS

68 (14.0%) were node-positive and 419 (86.0%) were node-negative. The sensitivity, specificity, positive, negative predictive values and accuracy were respectively, 66.2, 93.3, 61.6, 94.4, and 89.5% for dedicated axillary sequence and 64.7, 94.0, 63.8, 94.3, 89.9% for standard MR sequence The dedicated axillary and standard sequences s did not exhibit significant differences in detection of positive lymph nodes (AUC, 0.794 for standard and 0.798 for dedicated axillary sequence, P = 0.825). The cortical thickness appeared to be the most discriminative quantitative measurement using both axillary (AUC, 0.846) and standard sequences (AUC, 0.823), with high correlation coefficient (0.947).

CONCLUSION

Evaluation of axillary nodal status using standard breast MR imaging is comparable to dedicated axillary MR imaging.

Axillary Nodal Evaluation in Breast Cancer: State of the Art

Axillary lymph node (LN) metastasis is the most important predictor of overall recurrence and survival in patients with breast cancer, and accurate assessment of axillary LN involvement is an essential component in staging breast cancer. Axillary management in patients with breast cancer has become much less invasive and individualized with the introduction of sentinel LN biopsy (SLNB). Emerging evidence indicates that axillary LN dissection may be avoided in selected patients with node-positive as well as node-negative cancer. Thus, assessment of nodal disease burden to guide multidisciplinary treatment decision making is now considered to be a critical role of axillary imaging and can be achieved with axillary US, MRI, and US-guided biopsy. For the node-positive patients treated with neoadjuvant chemotherapy, restaging of the axilla with US and MRI and targeted axillary dissection in addition to SLNB is highly recommended to minimize the false-negative rate of SLNB. Efforts continue to develop prediction models that incorporate imaging features to predict nodal disease burden and to select proper candidates for SLNB. As methods of axillary nodal evaluation evolve, breast radiologists and surgeons must work closely to maximize the potential role of imaging and to provide the most optimized treatment for patients.

Supplemental Breast US Screening in Women with a Personal History of Breast Cancer: A Matched Cohort Study

Background There is limited research on supplemental screening breast US in women with a personal history of breast cancer (PHBC). Purpose To compare the performance of supplemental screening breast US in women with and women without a PHBC by using a matched cohort. Materials and Methods Consecutive asymptomatic women who underwent radiologist-performed supplemental breast US and mammography between January 2013 and December 2013 at a tertiary referral university hospital were retrospectively identified. Inclusion criteria were negative or benign findings at mammography, follow-up data for at least 1 year, first cancer stage of 0 to II in women with a PHBC, and incidence screening in women without a PHBC. The two groups were matched 1:1 according to age and breast density. Performance measures were compared with McNemar test, generalized estimating equation, or penalized likelihood logistic regression. Results A total of 3226 women with a PHBC were matched with 3226 women without a PHBC (mean age ± standard deviation, 52 years ± 9; mammographic breast density, fatty in 603 and dense in 2623). Fourteen cancers (six screen-detected, eight interval cancers) were found in women with a PHBC and 13 cancers (12 screen-detected, one interval cancer) in women without a PHBC. Supplemental US in women with a PHBC compared with women without a PHBC showed lower sensitivity (43% [95% confidence interval {CI}: 18%, 71%; six of 14 cancers] vs 92% [95% CI: 64%, 100%; 12 of 13 cancers]; P = .03), higher interval cancer rates (2.5 [95% CI: 1.1, 4.9; eight of 3226 women] vs 0.3 [95% CI: 0, 1.7; one of 3226 women] per 1000; P = .02), and higher specificity (92.8% [95% CI: 91.9%, 93.7%; 2982 of 3212 women] vs 89.3% [95% CI: 88.2%, 90.4%; 2870 of 3213 women]; P < .001), respectively. Conclusion Supplemental US screening in women with a personal history of breast cancer had lower sensitivity and higher interval cancer rate but higher specificity relative to women without a personal history of breast cancer. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Lee and Lee in this issue.

Asian Oceanian Radiology Forum 2018: International Education of Radiology in Asian Oceanian Countries

According to the reports presented at the Fourth Asian Oceanian Radiology Forum (AORF) 2018, organized by the Korean Society of Radiology during the Korean Congress of Radiology in September 2018 in Seoul, there is an increasing demand for the Asian Oceanian Society of Radiology and its member societies for international education in radiology in the Asian Oceanian region. In AORF 2018, the national delegates of the Asian Oceanian radiological partner societies primarily discussed their societies' activities and current status of international education in radiology.

Radiologic and Pathologic Findings of Atypical Ductal Hyperplasia in the Male Breast: Case Report and Literature Review

In this case report, we present the radiologic and pathologic findings of atypical ductal hyperplasia (ADH) in the male breast. It is well known that a high-risk lesion such as ADH is a precursor of breast cancer in females. However, the clinical significance of these lesions in the male breast is still uncertain because male breasts mainly consist of ducts without lobule formation, unlike the female breast. To our knowledge, imaging findings of ADH in the male breast have not been reported previously, except for a few studies on the pathologic findings of these lesions. Through this paper, we would like to present the possible imaging features of this high-risk lesion in the male breast and review the related literature.

Does Radiofrequency Ablation Induce Neoplastic Changes in Benign Thyroid Nodules: A Preliminary Study

BACKGROUND

To evaluate the clinical feasibility of radiofrequency ablation (RFA) of benign thyroid nodules along with cytomorphological alteration, and any malignant transformation through biopsy.

METHODS

The data were retrospectively collected between April 2008 and June 2013 and core needle biopsy (CNB) was performed on 16 benign thyroid nodules previously treated using RFA. The parameters of the patients were compared, between the time of enrollment and the last follow-up examination, using linear mixed model statistical analysis.

RESULTS

No atypical cells or neoplastic transformation were detected in the undertreated peripheral portion of treated benign nodules on the CNB specimen. RFA altered neither the thyroid capsule nor the thyroid tissue adjacent to the treated area. On histopathological examinations, we observed 81.2% acellular hyalinization, which was the most common finding. After a mean follow-up period of over 5 years, the mean volume of thyroid nodule had decreased to 6.4±4.2 mL, with a reduction rate of 81.3%±5.8% (P<0.0001).

CONCLUSION

RFA is a technically feasible treatment method for benign thyroid nodules, with no carcinogenic effect or tissue damage of the normal thyroid tissue adjacent to the RFA-treated zone.

Mammography, US, and MRI to Assess Outcomes of Invasive Breast Cancer with Extensive Intraductal Component: A Matched Cohort Study

Background An extensive intraductal component (EIC) in breast cancer is an independent risk factor for local recurrence after surgery, especially in young, premenopausal women. Few studies have analyzed long-term outcomes or imaging features of EIC-positive breast cancer. Purpose To assess the prognostic value of EIC on recurrence-free and overall survival in breast cancer and evaluate imaging features of EIC-positive breast cancer by using mammography, US, and MRI. Materials and Methods A retrospective study of 6816 consecutive women with surgically diagnosed invasive breast cancer between January 2007 and December 2012 was performed. After individual matching, women were allocated into either an EIC-positive or an EIC-negative group. Imaging factors associated with prognosis were investigated. The recurrence-free and overall survival rates were compared. Univariable and multivariable analyses were performed to analyze the effect of EIC. Results Among 6136 included women (mean age, 48.9 years ± 9.8), 1800 EIC-positive and 4336 EIC-negative breast cancers were identified. After matching according to EIC presence was performed, 1551 women were allocated into each group. The mean follow-up period was 79.9 months. The local-regional recurrence rate in the EIC-positive group was higher than that in the EIC-negative group (39.4% [63 of 160] vs 25.5% [37 of 145]; P = .001). However, there were no significant differences in total recurrence rate (hazard ratio [HR]: 1.2; 95% confidence interval [CI]: 0.9, 1.4; P = .21) or death (HR: 1.1; 95% CI: 0.8, 1.5; P = .45). EIC was not a significant independent factor for recurrence-free survival (HR: 1.1; 95% CI: 0.9, 1.4; P = .45) or death (HR: 1.1; 95% CI: 0.8, 1.6; P = .44) in multivariable analyses. Calcification and non-mass lesions were more commonly seen at US and MRI in the EIC-positive group than in the EIC-negative group (P < .001). Conclusion The presence of an extensive intraductal component in women with invasive breast cancer did not affect overall survival or recurrence-free survival. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Eby in this issue.

Echogenic foci in thyroid nodules: diagnostic performance with combination of TIRADS and echogenic foci

Background

The malignancy risks of various echogenic foci in thyroid nodules are not consistent. The association between malignancy and echogenic foci and various Thyroid Imaging Reporting and Data System (TIRADS) in thyroid nodules has not been evaluated. We evaluated the malignancy probability and diagnostic performance of thyroid nodules with various echogenic foci and in combination with TIRADS.

Methods

This retrospective study was approved by Institutional Review Board. The data were retrospectively collected from January 2013 to December 2014. In total, 954 patients (mean age, 50.8 years; range, 13–86 years) with 1112 nodules were included. Using χ² test, we determined the prevalence of benign and malignant nodules among those with and without echogenic foci; we associated each of 6 echogenic foci types with benign and malignant nodules. Diagnostic performance was compared between the 6 types alone and in combination with various TIRADS.

Results

Among 1112 nodules, 390 nodules (35.1%) were found to have echogenic foci, and 722 nodules (64.9%) were not. Among nodules with echogenic foci, 254 nodules (65.1%) were malignant. The punctate echogenic foci with comet-tail artifact showed malignancy rate of 77.8% in solid and predominantly solid nodules. Our study demonstrated relatively low PPV (33.3–56.4%) in nodules with large echogenic foci without shadowing, macrocalcification, and peripheral curvilinear or eggshell echogenic foci with or without shadowing. However, when combined with high suspicion category of TIRADS, PPV increased to 50.0–90.9%.

Conclusion

Combination with TIRADS with different types of echogenic foci offer better stratification of the malignancy risk.

Electronic supplementary material

The online version of this article (10.1186/s12880-019-0328-2) contains supplementary material, which is available to authorized users.

Validation of web-based thyroid imaging reporting and data system in atypia or follicular lesion of undetermined significance thyroid nodules

BACKGROUND

Atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) show variable malignancy risk. We validated the web-based predictive models and the scoring system by the American College of Radiology (ACR) for AUS/FLUS nodules to stratify the malignancy risk.

METHODS

From January 2011 to November 2014, 275 consecutive nodules diagnosed as AUS/FLUS were enrolled. The discrimination and calibration ability of a web-based scoring with inclusion of biopsy result and sonographic features, old web-based scoring model without biopsy result, and ACR models were assessed.

RESULTS

The areas under the receiver operating characteristic curve of the validation set were 0.670 for the new web-based model, 0.710 for the old web-based model, and 0.732 for the ACR scoring risk-stratification model. All models were well calibrated.

CONCLUSION

The web-based scoring risk-stratification model using the combined information of ultrasonography features and biopsy result for AUS/FLUS nodules to stratify malignancy risk presents an acceptable predictive accuracy.

Diagnostic Performance of Practice Guidelines for Thyroid Nodules: Thyroid Nodule Size versus Biopsy Rates

Background The diagnostic performance and unnecessary biopsy rates for evaluation of thyroid nodules varies among the current society guidelines. We hypothesized that diagnostic performance and unnecessary biopsy rates of different guidelines are largely determined by different thyroid size thresholds used as cutoff values that determine when to biopsy a thyroid nodule. Purpose To compare the malignancy risk, diagnostic performance, and unnecessary biopsy rates of three guidelines and evaluate the changes according to the nodule size cutoff for biopsy. Materials and Methods This retrospective study included 3323 consecutive thyroid nodules from 3190 patients between January 2013 and December 2013. US features were reviewed according to the American Thyroid Association (ATA), Korean Thyroid Association/Korean Society of Thyroid Radiology (KTA/KSThR), and American College of Radiology (ACR) guidelines. The diagnostic performance and unnecessary biopsy rates were calculated. The size cutoff of ATA and KTA/KSThR guidelines was varied and diagnostic performance and unnecessary biopsy rates were calculated and compared by using the generalized estimating equations method. Results A total of 856 (25.8%) thyroid nodules were diagnosed as malignant after surgical excision or biopsy. The highest sensitivity was observed with the KTA/KSThR guideline (93.5% [300 of 321]), followed by the ATA (92.5% [297 of 321]) and ACR guidelines (60.1% [193 of 321]). The highest specificity (75.2% [1216 of 1617], P < .001) with lowest unnecessary biopsy rate (20.7% [401 of 1938]) was observed with the ACR guideline. When the low-suspicion category in the ATA guideline modeled 2.5 cm instead of 1.5 cm as the size for biopsy, the unnecessary biopsy rate decreased to 43.6% (845 of 1938, 2.5-cm cutoff) compared with 55.1% (1068 of 1938, 1.5-cm cutoff) (P < .001). For the KTA/KSThR guidelines, the unnecessary biopsy rate decreased to 36.4% (706 of 1938, 2.5-cm cutoff) compared with 59.5% (1153 of 1938, 1.5-cm cutoff) (P < .001). Conclusion The diagnostic performance and unnecessary biopsy rates of the American Thyroid Association and the Korean Thyroid Association/Korean Society of Thyroid Radiology guidelines are strongly influenced by nodule size cutoff. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Foley in this issue.

Radial scars/complex sclerosing lesions of the breast: radiologic and clinicopathologic correlation

Background

We investigated the radiologic and clinical findings of radial scar and complex sclerosing lesions, and evaluated the rate of pathologic upgrade and predicting factors.

Methods

From review of our institution’s database from January 2006 to December 2012, we enrolled 82 radial scars/complex sclerosing lesions in 80 women; 51 by ultrasound guided core needle biopsy, 1 by mammography-guided stereotactic biopsy, and 38 by surgical excision. The initial biopsy pathology revealed that 53 lesions were without high risk lesions and 29 were with high risk lesions. Radiologic, clinical and pathological results were analyzed statistically and upgrade rates were calculated.

Results

Of the 82 lesions, 64 (78.0%) were surgically excised. After surgical excision, two were upgraded to DCIS and two were upgraded to lesions with high risk lesions. The rate of radial scar with high risk lesions was significantly higher in the surgical excision group (11.1% vs. 42.2%, p = 0.015), which also demonstrated larger lesion size (10.7 ± 6.5 vs. 7.1 ± 2.6 mm, p = 0.001). The diagnoses with high risk lesions on final pathological results showed older age (52.9 ± 6.0 years vs. 48.4 ± 6.7 years, p = 0.018).

Conclusions

Radial scars with and without high risk lesions showed no statistically significant differences in imaging, and gave relatively low cancer upgrade rates.

Electronic supplementary material

The online version of this article (10.1186/s12880-018-0279-z) contains supplementary material, which is available to authorized users.

Comparison of the Diagnostic Efficacy of Ultrasound-Guided Core Needle Biopsy With 18- Versus 20-Gauge Needles for Thyroid Nodules

OBJECTIVES

To compare the diagnostic efficacy, complication rate, and core needle biopsy (CNB) specimen yield in 18- versus 20-gauge ultrasound (US)-guided CNB for diagnosis of thyroid nodules.

METHODS

We included 81 consecutive thyroid nodules with US-guided biopsy by a 20-gauge core needle and 86 consecutive thyroid nodules with US-guided biopsy by an 18-gauge core needle during 2 years. The rate of inconclusive results, including nondiagnostic or atypia/follicular lesion of undetermined significance, was compared. The diagnostic performance for malignancy was assessed in nodules with a final diagnosis. The complication rate and CNB specimen yield were also compared.

RESULTS

Eighteen-gauge CNB showed a lower rate of nondiagnostic results (1.2% versus 8.6%; P = .024) than 20-gauge CNB; however, the rates of atypia/follicular lesion of undetermined significance and inconclusive results were not significantly different between the groups (P > .05). In addition, 18-gauge CNB showed higher sensitivity (75.0% versus 66.7%), a higher negative predictive value (83.9% versus 75.9%), and higher accuracy (78.3% versus 74.4%) for detecting malignancy than 20-gauge CNB, although the results did not achieve statistical significance. No major complications occurred in either of the CNB groups. The 18-gauge needle group had significantly fewer CNBs and larger specimen diameters (P < .001).

CONCLUSIONS

Core needle biopsy with an 18-gauge needle could be more effective for the diagnosis of thyroid nodules than CNB with a 20-gauge needle.

Growing BI-RADS category 3 lesions on follow-up breast ultrasound: malignancy rates and worrisome features

OBJECTIVE

  To determine the frequency and malignancy rate among growing Breast Imaging Reporting and Data System (BI-RADS) category 3 lesions diagnosed on follow-up breast ultrasound and to evaluate the radiological and clinical features associated with malignancy.  Methods:  Of the 38,482 women who underwent breast ultrasound between January 2010 and December 2011, 11,582 (30.1%) patients had 12,514 BI-RADS category 3 lesions. Patients whose lesions showed ≥20% enlargement on follow-up ultrasound were selected for this study. Radiological and clinical features including increase in the maximum diameter and anteroposterior dimension, morphological changes determined via ultrasound, palpability, multiplicity, new mass, baseline breast ultrasound indication and mammographic BI-RADS category were evaluated to determine their association with malignancy. Multivariate analyses were used to identify independent predictors of malignancy.  Results:  The frequency of growing BI-RADS category 3 lesions on follow-up ultrasound was 5.9% (738 of 12,514). Of 527 lesions examined in 459 patients with a follow-up duration of at least 24 months or with available pathological results, 26 proved to be malignant (4.9%). Multivariate analyses further indicated that sonographic morphological changes (OR, 7.662, p < 0.001) and development of suspicious features on follow-up mammography (OR, 3.812, p = 0.009) were associated with malignancy. Enlargement without associated suspicious mammography or sonographic morphological abnormalities had only 1.9 % (BI-RADS category 3) chance of malignancy.  Conclusion:  The malignancy rate for growing BI-RADS category 3 lesions is 4.9%. Sonographic morphological changes and suspicious mammographic features in these tumors are significantly associated with malignancy. Advances in knowledge: For lesions with an interval growth in the anteroposterior dimension of ≤50% without morphological changes, together with a benign mammogram, follow-up rather than an immediate biopsy can be recommended to reduce false-positive biopsy results. The risk of malignancy in lesions with a size increment but with no morphologic change on sonography is only 1.9%, compatible with continued BI-RADS category 3 classification.

Validation of Three Scoring Risk-Stratification Models for Thyroid Nodules

BACKGROUND

To minimize potential harm from overuse of fine-needle aspiration, Thyroid Imaging Reporting and Data Systems (TIRADSs) were developed for thyroid nodule risk stratification. The purpose of this study was to perform validation of three scoring risk-stratification models for thyroid nodules using ultrasonography features, a web-based malignancy risk-stratification system, and a model developed by the Korean Society of Thyroid Radiology and the American College of Radiology.

METHODS

Using ultrasonography images, radiologists assessed thyroid nodules according to the following criteria: internal content, echogenicity of the solid portion, shape, margin, and calcifications. A total of 954 patients (M_age = 50.8 years; range 13-86 years) with 1112 nodules were evaluated at the authors' institute from January 2013 to December 2014. The discrimination ability of the three models was assessed by estimating the area under the receiver operating characteristic curve. Additionally, Hosmer-Lemeshow goodness-of-fit statistics (calibration ability) were used to evaluate the agreement between the observed and expected number of nodules that were benign or malignant.

RESULTS

Thyroid malignancy was present in 37.2% (414/1112) of nodules. According to the 14-point web-based scoring risk-stratification system, malignancy risk ranged from 4.5% to 100.0% and was positively associated with an increase in risk scores. The areas under the receiver operating characteristic curve of the validation set were 0.884 in the web-based model, 0.891 in the Korean Society of Thyroid Radiology model, and 0.875 in the American College of Radiology model. The Hosmer-Lemeshow goodness-of-fit test indicated that the web-based scoring system showed the best-calibrated result, with a p-value of 0.078.

CONCLUSION

The three scoring risk-stratification models using the ultrasonography features of thyroid nodules to stratify malignancy risk showed acceptable predictive accuracy and similar areas under the curve. The web-based scoring system demonstrated the strongest agreement in calibration ability analysis. The easily accessible automated web-based scoring risk-stratification system may overcome the complexity of the various Thyroid Imaging Reporting and Data System guidelines and provide simplified guidance on personalized and optimal management in real practice.

Diagnostic performance of breast ultrasonography and MRI in the prediction of lymph node status after neoadjuvant chemotherapy for breast cancer

Background Neoadjuvant chemotherapy (NAC) is widely used to treat breast cancer. Sentinel lymph node biopsy has replaced axillary lymph node dissection in patients who convert to node-negative status after NAC. However, few studies have evaluated the diagnostic performance of ultrasonography and magnetic resonance imaging (MRI) in determining axillary lymph node status after NAC. Purpose To evaluate the diagnostic performance of breast ultrasonography and MRI in determining residual metastatic axillary lymph node status after NAC for breast cancer and to identify histopathological factors affecting radiological performance. Material and Methods This study included 157 patients who underwent initial and follow-up preoperative breast ultrasonography and MRI before NAC between January and December 2010. The sensitivity, specificity, negative and positive predictive values, and accuracy of ultrasonography, MRI, and their combinations were evaluated. Results The sensitivity of ultrasonography, MRI, and their combination in post-NAC axillary imaging was 60.00%, 57.33%, and 65.33%, respectively; the specificity was 60.47%, 72.09%, and 60.47%, respectively. The positive predictive value was highest with MRI (78.18%). On univariate analysis, positive estrogen receptor status was associated with misdiagnosis by ultrasonography ( P = 0.002), MRI ( P = 0.002), and their combination ( P = 0.001). When residual metastatic lymph nodes were present, lymph nodes with macrometastasis (>2.0 mm) were associated with correct ultrasonography-based diagnosis ( P = 0.0027). Conclusion Imaging assists in predicting axillary lymph node status in patients undergoing NAC; however, is imprudent to omit sentinel lymph node biopsy or axillary lymph node dissection for staging in women determined to be node-positive.

Detection of Malignancy Among Suspicious Thyroid Nodules <1 cm on Ultrasound with Various Thyroid Image Reporting and Data Systems

BACKGROUND

In patients undergoing active surveillance of papillary thyroid microcarcinoma, definitive therapy-usually preceded by a definitive diagnostic procedure-is not recommended until evidence of disease progression is obtained, as stated in the American Thyroid Association guidelines. This is because the deferring of definitive diagnosis and therapy until disease progression has no impact on the disease-specific survival. This study evaluated the malignancy rate and probability of thyroid nodules, which was further stratified based on the size cutoff value of 1 cm, with suspicious findings on ultrasonography (US), by using various malignant stratification systems.

METHODS

The data were retrospectively collected between January 2003 and June 2003 from nine university hospitals that had previously participated in the Korean Society of Thyroid Radiology multicenter study on the ultrasonographic differentiation between benign and malignant thyroid nodules. In total, 829 thyroid nodules from 711 patients (620 women, 91 men; M_age = 48.7 years; range 6-98 years; 351 malignant and 478 benign nodules) were included. The probability for malignancy of thyroid nodules was calculated, which was further stratified by size, by using four different types of malignant risk-stratification systems. The factors that could differentiate benign from malignant nodules were assessed using the chi-square test.

RESULTS

In the suspicious thyroid nodules <1 cm on US, the malignancy probability ranged from 77.4% to 82.8%; the lowest rate was found in the Korean Society of Thyroid Radiology multicenter study, whereas the highest rate was noted in the Web-based system. Thus, the probability of benign nodules among suspicious thyroid nodules <1 cm on US was 17.2-22.6%.

CONCLUSION

A biopsy should be considered before active surveillance to exclude benign nodules with suspicious US features, and could thus prevent unnecessary active surveillance and patient anxiety.

Radiofrequency ablation of small follicular neoplasms: initial clinical outcomes

BACKGROUND

In thyroid gland, radiofrequency ablation (RFA) has been applied to both recurrent cancers and benign nodules, although, according to the American Thyroid Association (ATA) and the Korean Society of Thyroid Radiology (KSThR) guidelines, surgery is the first-line treatment for follicular neoplasm. However, it has been argued that follicular neoplasm with lower risk of malignancy can be managed by close follow-up. In this study, we evaluated the effectiveness of RFA of small follicular neoplasms, examining reductions in volume and related clinical problems, and making observations over long-term follow-up.

METHODS

We evaluated 10 follicular neoplasms in 10 patients who were treated with RF ablation between 2009 and 2011. A RF generator and an 18-gauge internally cooled electrode were used to perform complete ablation of the whole nodules. Changes in nodules or ablated zones on follow-up ultrasound, and complications during and after RF ablation were evaluated.

RESULTS

The mean follow-up period was 66.4 ± 5.1 months (range: 60-76 months). In eight patients, single session of RF ablation was sufficient, while two patients required two sessions. There was a significant reduction in the mean volume (99.5 ± 1.0%) of lesions, with eight ablated lesions (8/10, 80%) disappearing completely on follow-up. No recurrences were found in any ablated zones at last follow-up. Transient mild neck pain (n = 6) occurred during the procedure without requiring any medication.

CONCLUSION

In addition to active surveillance, RF ablation may be an effective and safe alternative for the management of patients with small (<2 cm) follicular neoplasm suspected on thyroid biopsy and who strongly refuse surgery.