Jin You Kim

Unilateral breast cancer: screening of contralateral breast by using preoperative MR imaging reduces incidence of metachronous cancer.

PURPOSE To investigate the clinical effect of a single magnetic resonance (MR) imaging screening examination of the contralateral breast at preoperative evaluation in women with unilateral breast cancer. MATERIALS AND METHODS The institutional review board approved this study and waived informed consent. Among women with unilateral breast cancer who underwent curative surgery from 2004 to 2008, 1323 women (mean age, 46.8 years; range, 18-81 years) underwent mammography and ultrasonography (US) alone (comparison group) between January 2004 and December 2006; 1771 consecutive women (mean age, 48.2 years; range, 22-85 years) underwent mammography, US, and MR imaging (contralateral MR imaging-screened group) between January 2007 and December 2008. The incidence of synchronous cancer and the incidence of metachronous cancer in the contralateral breast were compared between groups. Multivariate Cox analysis was performed. Median follow-up was 56 months (range, 13-94 months). RESULTS Twenty-five synchronous contralateral cancers (13 invasive cancers, 12 ductal carcinomas in situ; mean invasive size, 14 mm [range, 1-35 mm]; 92% [12 of 13] of invasive tumors were node negative) were additionally detected with MR imaging in the MR imaging-screened group. The cumulative incidence of contralateral breast cancer at 45 months was 0.5% (nine of 1771) (95% confidence interval [CI]: 0.23%, 0.96%) for the MR imaging-screened group and 1.4% (18 of 1323) (95% CI: 0.81%, 2.14%) for the comparison group (P = .02). Contralateral MR imaging screening (hazard ratio, 0.37; 95% CI: 0.15, 0.92; P = .03) and estrogen receptor negativity (hazard ratio, 3.98; 95% CI: 1.60, 9.92; P = .003) were associated with risk of contralateral cancer diagnosis in multivariate analysis. CONCLUSION A single MR imaging screening examination of the contralateral breast in women with unilateral breast cancer increased synchronous cancer detection and was associated with decreased diagnosis of metachronous contralateral cancer within 45 months.

Two-View versus Single-View Shear-Wave Elastography: Comparison of Observer Performance in Differentiating Benign from Malignant Breast Masses

PURPOSE To determine whether two-view shear-wave elastography (SWE) improves the performance of radiologists in differentiating benign from malignant breast masses compared with single-view SWE. MATERIALS AND METHODS This prospective study was conducted with institutional review board approval, and written informed consent was obtained. B-mode ultrasonographic (US) and orthogonal SWE images were obtained for 219 breast masses (136 benign and 83 malignant; mean size, 14.8 mm) in 219 consecutive women (mean age, 47.9 years; range, 20-78 years). Five blinded radiologists independently assessed the likelihood of malignancy for three data sets: B-mode US alone, B-mode US and single-view SWE, and B-mode US and two-view SWE. Interobserver agreement regarding Breast Imaging Reporting and Data System (BI-RADS) category and the area under the receiver operating characteristic curve (AUC) of each data set were compared. RESULTS Interobserver agreement was moderate (κ = 0.560 ± 0.015 [standard error of the mean]) for BI-RADS category assessment with B-mode US alone. When SWE was added to B-mode US, five readers showed substantial interobserver agreement (κ = 0.629 ± 0.017 for single-view SWE; κ = 0.651 ± 0.014 for two-view SWE). The mean AUC of B-mode US was 0.870 (range, 0.855-0.884). The AUC of B-mode US and two-view SWE (average, 0.928; range, 0.904-0.941) was higher than that of B-mode US and single-view SWE (average, 0.900; range, 0.890-0.920), with statistically significant differences for three readers (P ≤ .003). CONCLUSION The performance of radiologists in differentiating benign from malignant breast masses was improved when B-mode US was combined with two-view SWE compared with that when B-mode US was combined with single-view SWE.

The Breast Tumor Strain Ratio Is a Predictive Parameter for Axillary Lymph Node Metastasis in Patients With Invasive Breast Cancer

OBJECTIVE The purpose of this study was to evaluate the association between the breast tumor strain ratio and axillary lymph node metastasis in patients with invasive breast cancer. MATERIALS AND METHODS The records of 284 patients with invasive breast cancer who underwent ultrasound elastography before surgery between March 2013 and May 2014 were reviewed retrospectively. For women with multifocal or bilateral cancer, the largest tumor was included. An experienced radiologist performed ultrasound elastography and measured the strain ratio, which is defined as the fat-to-lesion ratio and is indicative of the relative stiffness of the breast lesion, using dedicated software within the ultrasound equipment. The associations between axillary lymph node metastasis with the tumor strain ratio and clinical and biologic variables were evaluated using univariate and multivariate logistic regression analyses. RESULTS Among 284 tumors, 85 (29.9%) showed axillary lymph node metastasis by surgical histopathologic analysis. The strain ratio was statistically significantly higher in tumors with axillary lymph node metastasis than in those without axillary lymph node metastasis (mean ± SD, 5.19 ± 1.28 vs 4.17 ± 1.30, respectively; p < 0.001). On univariate analysis, a higher strain ratio (> 3.89), larger tumor size (> 2 cm), higher histologic grade (grade 3), presence of lymphovascular invasion, palpability, and higher expression of Ki-67 (≥ 14%) were statistically significantly associated with axillary lymph node metastasis. On multivariate analysis, a higher strain ratio (> 3.89) (odds ratio [OR], 14.208; p < 0.001), presence of lymphovascular invasion (OR, 17.437; p < 0.001), and higher expression of Ki-67 (≥ 14%) (OR, 3.744; p = 0.002) maintained independent significance for predicting axillary lymph node metastasis. CONCLUSION The breast tumor strain ratio on ultrasound elastography is associated independently with axillary lymph node metastasis in patients with invasive breast cancer.

Preoperative 18F-FDG PET/CT predicts disease-free survival in patients with primary invasive ductal breast cancer.

Background Previous studies have correlated the maximum standardized uptake value (SUVmax) of breast cancer lesions with histological and biological characteristics such as tumor size, histologic grade, or hormonal receptor expression status. However, controversy remains concerning the prognostic value of SUVmax in breast cancer. Purpose To determine if the SUVmax of a tumor on 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) is associated with disease-free survival in patients with primary invasive ductal breast cancer. Material and Methods The institutional review board of our hospital approved this retrospective study. From 2009 to 2011, 508 women (mean age, 53.6 years; age range, 26–85 years) with newly diagnosed invasive ductal breast cancer who had undergone preoperative 18F-FDG PET/CT followed by surgery were identified. Clinicopathological variables and FDG uptake quantified by SUVmax were analyzed. The Cox proportional hazards model was used to evaluate the association between SUVmax and disease-free survival after controlling for clinicopathological parameters. Results There were 21 recurrences at a median follow-up of 46 months. The mean SUVmax of the primary tumor was significantly higher in patients with a recurrence than those who remained disease-free (9.5 ± 3.5 vs. 6.6 ± 4.2, P < 0.001). A receiver operating characteristic curve indicated that a SUVmax of 5.95 was the optimal cut-off value to predict disease-free survival. Multivariate analysis identified a high SUVmax (≥5.95) and high T stage as independent significant variables associated with worse disease-free survival. Conclusion A high primary tumor SUVmax on 18F-FDG PET/CT was an independent factor associated with worse disease-free survival in patients with primary invasive ductal breast cancer.

Computer-aided Diagnosis–generated Kinetic Features of Breast Cancer at Preoperative MR Imaging: Association with Disease-free Survival of Patients with Primary Operable Invasive Breast Cancer

Purpose To retrospectively investigate the relationship between the kinetic features of breast cancer assessed with computer-aided diagnosis (CAD) at preoperative magnetic resonance (MR) imaging and disease-free survival in patients with primary operable invasive breast cancer. Materials and Methods This retrospective study was approved by the institutional review board. The requirement to obtain informed consent was waived. The authors identified 329 consecutive women (mean age, 52.9 years; age range, 32-88 years) with newly diagnosed invasive breast cancer who had undergone preoperative MR imaging and surgery between January 2012 and February 2013. All MR images were retrospectively reviewed by using a commercially available CAD system, and the following kinetic parameters were noted for each lesion: peak enhancement (highest pixel signal intensity in the first series obtained after administration of contrast material), angio-volume (total volume of the enhancing lesion), and delayed enhancement profiles (the proportions of washout, plateau, and persistently enhancing component within a tumor). Cox proportional hazards modeling was used to identify the relationship between CAD-generated kinetics and disease-free survival after adjusting for clinical-pathologic variables. Results A total of 36 recurrences developed at a median follow-up of 50 months (range, 15-55 months). CAD-measured peak enhancement at preoperative MR imaging enabled differentiation between patients with and patients without recurrence (area under the receiver operating characteristic curve = 0.728; 95% confidence interval [CI]: 0.676, 0.775; P < .001). Multivariate Cox analysis showed that a higher peak enhancement (hazard ratio [HR] = 1.001; 95% CI: 1.000, 1.002; P = .004), a higher washout component (HR = 1.029; 95% CI: 1.005, 1.054; P = .017), and lymphovascular invasion at histopathologic examination (HR = 3.011; 95% CI: 1.302, 6.962; P = .010) were associated with poorer disease-free survival. Conclusion Higher values of CAD-measured peak enhancement and washout component at preoperative MR imaging were significantly associated with poorer disease-free survival of patients with primary operable breast cancer.

Diffusion-weighted magnetic resonance imaging in the differentiation of endometriomas from hemorrhagic cysts in the ovary.

Background The classic magnetic resonance imaging (MRI) feature of endometriomas is the shading sign, which is characterized by T2-shortening in ovarian cystic lesions that are hyperintense on T1-weighted images. The shading sign is infrequently observed in hemorrhagic ovarian cysts. Purpose To investigate the value of MRI with diffusion-weighted imaging (DWI) for distinguishing endometriomas from hemorrhagic cysts in the ovary. Material and Methods This retrospective study included 91 patients with 98 ovarian endometriomas and 21 hemorrhagic ovarian cysts that were confirmed pathologically, who had undergone MRI with DWI. Two radiologists compared MRI features, including size, bilaterality, multilocularity, the shading sign, the ovarian lesion/muscle signal intensity ratio at T2-weighted images, and T2 dark spots, between endometriomas and hemorrhagic cysts. We also compared the mean ADC value between endometriomas and hemorrhagic cysts, and determined the optimal cutoff ADC value for differentiating endometriomas from hemorrhagic cysts. Results The size and mean ADC values were significantly different between endometriomas and hemorrhagic cysts. The mean ADC values of endometriomas and hemorrhagic cysts were 1.06 ± 0.38 × 10 −3 mm2/s and 0.73 ± 0.29 × 10−3 mm2/s, respectively (P < 0.002). The optimal cutoff ADC value for differentiating endometriomas from hemorrhagic cysts was 0.849 × 10−3 mm2/s (sensitivity, 77.6%; specificity, 76.2%). Conclusion The addition of DWI could help in differentiating endometriomas from hemorrhagic cysts in the ovary, when conventional MRI is challenging.

Early-stage invasive ductal carcinoma: Association of tumor apparent diffusion coefficient values with axillary lymph node metastasis

PURPOSE To evaluate any association between tumor apparent diffusion coefficient (ADC) values and axillary lymph node metastasis (ALNM) in early-stage invasive ductal carcinoma. MATERIALS AND METHODS Records of 270 invasive ductal carcinoma patients with stages T1 and T2 disease who underwent breast magnetic resonance imaging, including diffusion-weighted imaging with b values of 0 and 1000s/mm(2) were reviewed retrospectively. The tumor ADC values were analyzed for their utility in predicting ALNM using multivariate regression analysis and receiver operating characteristic (ROC) curve analysis. RESULTS Of the 270 patients, 58 (21.5%) experienced ALNM. The mean tumor ADC values were significantly lower in patients with ALNM than in those without metastasis (0.880 × 10(-3) vs. 0.999 × 10(-3)mm(2)/s, P<0.001). A ROC curve demonstrated a tumor ADC value of 0.991 × 10(-3)mm(2)/s to be the optimal cut-off for predicting ALNM. In a multivariate analysis, lower tumor ADC (≤ 0.991 × 10(-3)mm(2)/s; adjusted odds ratio (OR)=5.861, P<0.001), large tumor size (>2 cm; adjusted OR=3.156, P=0.002) and the presence of lymphovascular invasion (adjusted OR=4.125, P<0.001) were independent variables associated with ALNM. When tumor ADC value was added to known risk factors (i.e., tumor size and lymphovascular invasion), a significant improvement in the accuracy of risk prediction for axillary node metastasis was shown (c-statistic=0.758 vs. 0.816, P=0.026). CONCLUSION In early-stage invasive ductal carcinoma, lower tumor ADC values are associated with the presence of ALNM.

Smaller Reduction in 3D Breast Density Associated With Subsequent Cancer Recurrence in Patients With Breast Cancer Receiving Adjuvant Tamoxifen Therapy

OBJECTIVE The purpose of this study was to retrospectively investigate whether 3D breast density changes measured using MRI were associated with recurrent cancer in patients with breast cancer who received adjuvant tamoxifen. MATERIALS AND METHODS A search of the breast MRI database (2007-2008) revealed a dataset that included 80 women (mean age, 44 years; range, 27-68 years) with breast cancer who underwent breast-conserving surgery, adjuvant tamoxifen treatment, and breast MRI before and after tamoxifen. The following clinicopathologic variables were collected: age, body mass index, menopausal status, family history, tumor stage, tumor grade, hormonal receptor status, and adjuvant chemotherapy status. MRI variables (total breast volume, fibro-glandular volume, and breast density) were measured for the contralateral untreated breast before and after tamoxifen treatment, and the percentage changes were recorded. A multivariate logistic regression analysis was performed to identify independent factors that were associated with cancer recurrence. RESULTS Overall, 12 (15%) of the 80 women developed recurrence. No recurrent cancers were found in the remaining 68 patients (85%) at a median follow-up of 48 months (range, 37-60 months). Percentage reduction of breast density after tamoxifen was the only independent factor associated with recurrence (adjusted odds ratio [OR] = 0.848, 95% CI = 0.769-0.935, and p = 0.001 for observer 1; adjusted OR = 0.957, 95% CI = 0.919-0.996, and p = 0.032 for observer 2) in the multivariate analysis. CONCLUSION Three-dimensional breast density changes measured using MRI during tamoxifen treatment were an independent factor associated with cancer recurrence in patients with breast cancer who received adjuvant tamoxifen.

Magnetic resonance imaging characteristics of invasive breast cancer in women aged less than 35 years

Background With regard to clinicopathological findings and disease prognosis, breast cancer in young women is different from that in older women. However, few studies have investigated magnetic resonance imaging (MRI) characteristics of young age-onset breast cancer. Purpose To retrospectively evaluate and compare the MR images and clinicopathological characteristics of invasive breast cancer in young women (aged <35 years) with those of breast cancers in older premenopausal women (35–45 years). Material and Methods A total of 270 invasive breast cancers in 266 premenopausal women aged 45 years and younger who underwent preoperative breast MRI and curative surgery were identified between 2009 and 2013. The subjects were divided into a young group (<35 years, n = 56) and an older group (35–45 years, n = 214). MRI features and clinicopathological data were compared between the two groups. Results The young group had more positive axillary lymph nodes, higher histologic grade, negative estrogen receptor (ER), negative progesterone receptor (PR), and higher p53 and Ki-67 expression compared to the older group. Using MRI, the young group was more likely to display a round/oval or lobular mass shape, a smooth mass margin, and a high signal intensity on T2-weighted images when compared to the older group. In multivariate analysis, positive axillary nodal status (adjusted odds ratio [OR], 4.070; P = 0.002), higher expression of p53 (adjusted OR, 2.902; P = 0.038), lobular mass shape (adjusted OR, 4.979; P = 0.028), and smooth mass margin (adjusted OR, 5.123; P = 0.048) were independently associated with the young group. Conclusion MR morphologic features, including lobular mass shape and smooth mass margin, were independently associated with breast cancer in young women, in addition to positive axillary nodal status and higher p53 expression status.

Predictive Value of Cardiac Magnetic Resonance Imaging-Derived Myocardial Strain for Poor Outcomes in Patients with Acute Myocarditis

Objective To evaluate the utility of cardiovascular magnetic resonance (CMR)-derived myocardial strain measurement for the prediction of poor outcomes in patients with acute myocarditis. Materials and Methods We retrospectively analyzed data from 37 patients with acute myocarditis who underwent CMR. Left ventricular (LV) size, LV mass index, ejection fraction and presence of myocardial late gadolinium enhancement (LGE) were analyzed. LV circumferential strain (EccSAX), radial strain (ErrSAX) from mid-ventricular level short-axis cine views and LV longitudinal strain (EllLV), radial strain (ErrLax) measurements from 2-chamber long-axis views were obtained. In total, 31 of 37 patients (83.8%) underwent follow-up echocardiography. The primary outcome was major adverse cardiovascular event (MACE). Incomplete LV functional recovery was a secondary outcome. Results During an average follow-up of 41 months, 11 of 37 patients (29.7%) experienced MACE. Multivariable Cox proportional hazard regression analysis, which included LV mass index, LV ejection fraction, the presence of LGE, EccSAX, ErrSAX, EllLV, and ErrLax values, indicated that the presence of LGE (hazard ratio, 42.88; p = 0.014), together with ErrLax (hazard ratio, 0.77 per 1%, p = 0.004), was a significant predictor of MACE. Kaplan-Meier analysis demonstrated worse outcomes in patient with LGE and an ErrLax value ≤ 9.48%. Multivariable backward regression analysis revealed that ErrLax values were the only significant predictors of LV functional recovery (hazard ratio, 0.54 per 1%; p = 0.042). Conclusion CMR-derived ErrLax values can predict poor outcomes, both MACE and incomplete LV functional recovery, in patients with acute myocarditis, while LGE is only a predictor of MACE.