Woo Jung Choi

Reassessment and Follow-Up Results of BI-RADS Category 3 Lesions Detected on Screening Breast Ultrasound

OBJECTIVE The purpose of this study is to determine the frequency and the malignancy rate of BI-RADS category 3 lesions detected on screening breast ultrasound and to reassess whether they satisfied the requirements of the American College of Radiology Imaging Network (ACRIN) 6666 protocol. MATERIALS AND METHODS Of 28,796 asymptomatic women who underwent screening mammography during 2 years, 12,187 underwent additional ultrasound as part of the screening. Patients for whom BI-RADS category 3 lesions were seen on the ultrasound were selected. We reviewed the initial ultrasound showing BI-RADS category 3 lesions and mammograms. We also investigated the clinical outcome of these lesions using the reference standard of a combination of pathologic analysis and follow-up for at least 24 months. RESULTS The frequency of BI-RADS category 3 lesions detected on screening ultrasound was 14.6% (1783/12,187). Of the 1164 patients with a follow-up duration of at least 24 months or whose lesions were biopsied, eight were eventually proven to have malignancy (0.7%). The malignancy rate was 2.2% (4/184) for patients with abnormal mammograms and 0.4% (4/980) for those with normal mammograms. When the ACRIN 6666 protocols were strictly applied, 225 (19.3%) lesions were retrospectively recategorized as BI-RADS category 4 (n = 12) or category 2 (n = 213). All detected malignancies were early breast cancers with no lymph node metastasis. CONCLUSION Although the frequency of ultrasound BI-RADS category 3 lesions is considerably high (14.6%), the malignancy rate is very low (0.7%), especially in patients with a normal mammogram. Therefore, with BI-RADS category 3 assessment, careful evaluation is required to avoid unnecessary short-interval follow-up or biopsy.

Breast Cancer Detected at Screening US: Survival Rates and Clinical-Pathologic and Imaging Factors Associated with Recurrence

Purpose To determine the survival rates and clinical-pathologic and imaging factors associated with recurrence in women with breast cancer detected at screening ultrasonography (US). Materials and Methods This study was approved by the institutional review board, and the requirement to obtain informed consent was waived. A retrospective review of the databases of four institutions identified 501 women (median age, 47 years; range, 27-74 years) with breast cancer (425 invasive cancers and 76 ductal carcinoma in situ) detected at screening US between January 2004 and March 2011. Five-year overall survival (OS) and recurrence-free survival (RFS) rates were estimated, and the clinical-pathologic and imaging data were collected. Multivariate analysis was performed by using Cox proportional hazard regression to determine factors associated with recurrence. Results At a median follow-up of 7.0 years (range, 5.0-12.1 years), 15 (3.0%) recurrences were detected: five in ipsilateral breast and 10 in contralateral breast. The 5-year OS and RFS rates were 100% and 98.0% (95% confidence interval [CI]: 96.8%, 99.2%), respectively. In patients with invasive cancers, age younger than 40 years (hazard ratio: 3.632 [95% CI: 1.099, 11.998]; P = .032), the triple-negative subtype (hazard ratio: 7.498 [95% CI: 2.266, 24.816]; P = .001), and Breast Imaging Reporting and Data System (BI-RADS) category 4A lesions (hazard ratio: 5.113 [95% CI: 1.532, 17.195]; P = .008) were associated with recurrence. Conclusion Women with breast cancers detected at screening US have excellent outcomes, with a 5-year RFS rate of 98.0%. However, in patients with invasive breast cancer, age younger than 40 years, the triple-negative subtype, and BI-RADS category 4A lesions were associated with recurrence.

Predictive Clinicopathologic and Dynamic Contrast-Enhanced MRI Findings for Tumor Response to Neoadjuvant Chemotherapy in Triple-Negative Breast Cancer

OBJECTIVE The purpose of this study is to investigate whether clinicopathologic factors and dynamic contrast-enhanced MRI (DCE-MRI) features are associated with pathologic tumor response to neoadjuvant chemotherapy (NAC) in patients with triple-negative breast cancer (TNBC). MATERIALS AND METHODS Seventy-three patients with TNBC who underwent pre-NAC MRI, completed NAC, and underwent surgery between January 2009 and December 2010 were included in the study. MRI features and clinicopathologic factors for predicting pathologic responses were analyzed, and residual tumor sizes, as measured using MRI and surgical specimens, were evaluated. RESULTS Of 73 study patients, 20 (27%) had a pathologic complete response (pCR). Homogeneous enhancement on pre-NAC MRI (odds ratio from multivariate analysis, 14.66) and a concentric shrinkage pattern of tumor volume reduction on post-NAC MRI (odds ratio, 8.63) were independently associated with pCR. Residual tumor sizes, as measured using MRI and surgical specimens, showed a strong correlation (r = 0.652, p < 0.001). The correlation for residual tumor sizes was stronger for patients with pCR (r = 0.600, p < 0.001) and those with a concentric shrinkage pattern (r = 0.818, p < 0.001) than for patients with a response other than near pCR or pCR (i.e., the non-pCR group) (r = -0.128, p = 0.590) and patients with a dendritic shrinkage pattern of tumor volume reduction (r = 0.270, p = 0.182). CONCLUSION Homogeneous enhancement of tumors on pre-NAC MRI and the presence of a concentric shrinkage pattern after NAC are associated with pCR in patients with TNBC. Residual tumor sizes on MRI and surgical specimens tended to show a stronger correlation in the pCR group or the concentric shrinkage group than in the non-pCR group or the dendritic shrinkage group.

Diagnostic Performance of Fused Diffusion-Weighted Imaging Using Unenhanced or Postcontrast T1-Weighted MR Imaging in Patients With Breast Cancer

AbstractTo evaluate the diagnostic performance of fused diffusion-weighted imaging (DWI) using either unenhanced (UFMR) or early postcontrast T1-weighted imaging (PCFMR) to detect and characterize breast lesions in patients with breast cancer.This retrospective observational study was approved by institutional review board in our hospital and informed consents were waived. We retrospectively selected 87 consecutive patients who underwent preoperative breast magnetic resonance imaging, including DWI and definitive surgery. Both UFMR and PCFMR were reviewed by 5 radiologists for detection, lesion size, Breast Imaging Reporting and Data System final assessment, the probability of malignancy, lesion conspicuity, and apparent diffusion coefficients.A total of 129 lesions were identified by at least 2 readers on UFMR or PCFMR. Of 645 potentially detected lesions, there were 528 (82%) with UFMR and 554 (86%) with PCFMR. Malignant lesions or index cancers showed significantly higher detection rates than benign or additional lesions on both UFMR and PCFMR (P < 0.05). Area under the characteristic curves (AUCs) for predicting malignancy ranged 0.927 to 0.986 for UFMR, and 0.936 to 0.993 for PCFMR, which was not significantly different. Lesion conspicuity was significantly higher on PCFMR than UFMR (8.59 ± 1.67 vs 9.19 ± 1.36, respectively; P < 0.05) across 5 readers. Mean intraclass correlation coefficients for lesion size on UFMR and PCFMR were 0.89 and 0.92, respectively.Detection rates of index malignant lesions were similar for UFMR and PCFMR. Interobserver agreement for final assessments was reliable across 5 readers. Diagnostic accuracy for predicting malignancy with UFMR versus PCFMR was similar, although lesion conspicuity was significantly greater with the latter.

Detection and characterization of breast lesions in a selective diagnostic population: diagnostic accuracy study for comparison between one-view digital breast tomosynthesis and two-view full-field digital mammography

OBJECTIVE To compare the performance of one-view digital breast tomosynthesis (DBT) and two-view full-field digital mammography (FFDM) in the detection and characterization of breast lesions in a selective diagnostic population. METHODS A total of 598 breasts of 319 diagnostic patients were prospectively enrolled. Participants underwent bilateral one-view, mediolateral oblique (MLO) DBT and two-view, craniocaudal and MLO FFDM. The sensitivity and specificity of these methods and their classification into correct Breast Imaging-Reporting and Data System (BI-RADS) categories were compared. These methods were also compared in patients subgrouped by mammographic parenchymal density. Receiver operating characteristic (ROC) curve analysis was performed using the probability of cancer scores. RESULTS DBT had higher overall sensitivity than FFDM (88.7% vs 80.7%, p = 0.001). Subgroup analyses showed that DBT had significantly higher sensitivity in assessing dense breasts and invasive cancers than FFDM. The BI-RADS category assessment was significantly better for DBT than for FFDM. The differences between the two modalities in specificity (94.1% and 93.2% for FFDM and DBT) were not significant (p = 0.664). The area under the ROC curves using the probability of cancer scores were 0.93 [95% confidence interval (CI), 0.91-0.95] for FFDM and 0.96 (95% CI, 0.94-0.97) for DBT (p = 0.005). ROC curve analysis indicated that most of the increased performance of DBT was due to dense breasts. CONCLUSION A beneficial effect on the detection and characterization of breast lesions was found for one-view DBT compared with two-view FFDM in a selective diagnostic population. Improvements were especially enhanced in females with dense breasts. These results need to be examined in studies using large-scale consecutive sampling of a diagnostic population. ADVANCES IN KNOWLEDGE In this study, using selective diagnostic study cases, one-view DBT offered improved reader performance compared with two-view FFDM for detection and characterization of breast cancers.

Association of BRCA Mutation Types, Imaging Features, and Pathologic Findings in Patients With Breast Cancer With BRCA1 and BRCA2 Mutations

OBJECTIVE The purpose of this study is to retrospectively evaluate the relationships between the BRCA mutation types, imaging features, and pathologic findings of breast cancers in BRCA1 and BRCA2 mutation carriers. MATERIALS AND METHODS We identified patients with breast cancer with BRCA gene mutations from January 2000 to December 2014. After excluding patients who underwent lesion excision before MRI, 99 BRCA1 and 103 BRCA2 lesions in 187 women (mean age, 39.7 and 40.4 years, respectively) were enrolled. Mammographic, sonographic, and MRI scans were reviewed according to the BI-RADS lexicon (5th edition). Pathologic data were reviewed, including the immunohistochemistry findings. The relationships between the BRCA mutations and both imaging and pathologic findings were analyzed. RESULTS The distribution of molecular subtypes of tumors significantly differed by the mutation type. BRCA1 tumors were associated with the triple-negative subtype, whereas BRCA2 tumors were associated with the luminal B subtype (p = 0.002). At MRI, breast cancers with BRCA1 mutations exhibited a circumscribed margin (p = 0.032) and rim enhancement (p = 0.013). No significant differences in mass shape or kinetic features were observed at MRI. Cancers in BRCA1 mutation carriers tended to develop in the posterior location in the breast (p = 0.034). At mammography, no significant difference in the prevalence of calcifications was observed according to the mutation type. At sonography, BRCA1 lesions were found to be associated with posterior acoustic enhancement (p < 0.0001). CONCLUSION Breast cancers with BRCA1 mutations tend to exhibit benign morphologic features at MRI, mammography, and sonography, compared with BRCA2 mutations. Lesion location may represent another difference on imaging among various genetic phenotypes.

Comparison of Automated Breast Volume Scanning and Hand- Held Ultrasound in the Detection of Breast Cancer: an Analysis of 5,566 Patient Evaluations

BACKGROUND The purpose of this study was to compare the accuracy and effectiveness of automated breast volume scanning (ABVS) and hand-held ultrasound (HHUS) in the detection of breast cancer in a large population group with a long-term follow-up, and to investigate whether different ultrasound systems may influence the estimation of cancer detection. MATERIALS AND METHODS Institutional review board approval was obtained for this retrospective study, and informed consent was waived. From September 2010 to August 2011, a total of 1,866 ABVS and 3,700 HHUS participants, who underwent these procedures at our institute, were included in this study. Cancers occurring during the study and subsequent follow-up were evaluated. The reference standard was a combination of histology and follow-up imaging (≥12 months). The recall rate, cancer detection yield, diagnostic accuracy, sensitivity, specificity, and positive (PPV) and negative (NPV) predictive values were calculated with exact 95% confidence intervals. RESULTS The recall rate was 2.57 per 1,000 (48/1,866) for ABVS and 3.57 per 1,000 (132/3,700) for HHUS, with ? significant difference (p=0.048). The cancer detection yield was 3.8 per 1,000 for ABVS and 2.7 per 1,000 for HHUS. The diagnostic accuracy was 97.7% for ABVS and 96.5% for HHUS with statistical significance (p=0.018). The specificity of ABVS and HHUS were 97.8%, 96.7%, respectively (p=0.022). CONCLUSIONS ABVS shows a comparable diagnostic performance to HHUS. ABVS is an effective supplemental tool for mammography in breast cancer detection in a large population.

Are there any sonographic features that can be used to differentiate between small triple-negative breast cancer and fibroadenoma?

Purpose Our study investigated whether any sonographic findings could be useful for differentiating between small triple-negative breast cancer (TNBC) and fibroadenoma. Methods This retrospective study was approved by our Institutional Review Board, which waived the requirement for patient consent. From January 2009 to December 2010, the sonographic features of 181 pathologically proven TNBC tumors and 172 fibroadenomas measuring less than or equal to 2 cm in the longest dimension were reviewed and analyzed according to the fifth edition of the Breast Imaging Reporting and Data System (BI-RADS) lexicon. Mean tumor roundness was also measured using in-house software. Results The median longest lesion dimension was 16 mm (range, 13 to 18 mm) in TNBCs and 13 mm (range, 10 to 16 mm) in fibroadenomas. In comparison to fibroadenomas, small TNBC tumors presented with a higher incidence of irregular shapes (66.9%), noncircumscribed margins (91.7%), hypoechoic echotexture (59.1%), posterior acoustic enhancement (65.2%), and associated features (24.4%). Most TNBCs were classified as BI-RADS category 4 (65.2%) or 5 (28.2%). The mean tumor roundness of small TNBCs was greater than that of fibroadenomas (60%±12% vs. 53%±13%). Multivariate analysis showed that older patient age, irregular shape, nonparallel orientation, posterior acoustic enhancement, associated features, a BI-RADS final assessment category of 4 or 5, and greater tumor roundness were significant independent factors indicative of TNBCs. Conclusion TNBC tumors tend to demonstrate more suspicious sonographic features and greater tumor roundness than fibroadenomas. These features may have the potential to help differentiate between small TNBCs and fibroadenomas.

Breast MR Imaging before Surgery: Outcomes in Patients with Invasive Lobular Carcinoma by Using Propensity Score Matching

Purpose To investigate the association between preoperative breast magnetic resonance (MR) imaging and surgical outcomes in patients with invasive lobular carcinoma (ILC) by using propensity score matching to decide whether MR examination is beneficial in the ILC subtype of breast cancer. Materials and Methods The authors identified 603 patients with ILC who underwent surgery between January 2005 and December 2016. Of the 603 patients, 369 (61.2%) underwent MR imaging. The authors calculated the MR detection rate of additional lesions that were occult at mammography and ultrasonography and analyzed any alterations in surgical management. After propensity score matching, 196 pairs of patients were allocated to the groups, and the 17 possible confounding variables regarding patient and tumor characteristics and various clinical features were well balanced between the patients who underwent MR imaging and those who did not. Surgical outcomes were compared. Results Of the 369 patients who underwent MR imaging, additional lesions were detected in 145 (39.3%); 95 of the 145 patients (65.5%) had malignant lesions. A change in surgical management occurred because of MR findings in 94 of the 369 patients (25.5%). According to pathologic findings, this change was appropriate for 84 of the 94 patients (89.4%). In the propensity score-matched analysis, breast MR imaging was associated with lower odds of repeat surgery (odds ratio, 0.140; P < .001) and similar likelihood of initial mastectomy (odds ratio, 0.876; P = .528) and final mastectomy (odds ratio, 0.744; P = .151) compared with patients without breast MR imaging. Conclusion Preoperative MR imaging is useful for detecting additional synchronous malignancy and significantly reducing the likelihood of repeat surgery without increasing the rate of mastectomy in patients with ILC.

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.