Does adding diffuse optical tomography to sonography improve differentiation between benign and malignant breast lesions? Observer performance study.

OBJECTIVES: The purpose of this study was to investigate the added value of diffuse optical tomographic categories combined with conventional sonography for differentiating between benign and malignant breast lesions. METHODS: In this retrospective database review, we included 145 breast lesions (116 benign and 29 malignant) from 145 women (mean age, 46 years; range, 16-86 years). Five radiologists independently reviewed sonograms with and without a diffuse optical tomographic category. Each lesion was scored on a scale of 0% to 100% for suspicion of malignancy and rated according to the American College of Radiology Breast Imaging Reporting and Data System classification. Diagnostic performance was analyzed by comparing area under receiver operating characteristic curve values. Reader agreement was assessed by intraclass correlation coefficients. RESULTS: In the multireader multicase receiver operating characteristic analysis, adding a diffuse optical tomographic category to sonography improved the diagnostic accuracy of sonography (mean areas under the curve, 0.923 for sonography alone and 0.969 for sonography with diffuse optical tomography; P = .039). The interobserver correlation was also improved (0.798 for sonography alone and 0.904 for sonography with diffuse optical tomography). The specificity increased for 4 reviewers from a mean of 19.5% to 45.8% (P < .001 for reviewers 1-4; P = .238 for reviewer 5) with no significant change in the sensitivity. When the diffuse optical tomographic category was applied strictly, the specificity increased for all reviewers from a mean of 19.5% to 68.3% (P < .001 for all reviewers) with no significant change in the sensitivity. CONCLUSIONS: The addition of diffuse optical tomographic categories to sonography may improve diagnostic performance and markedly decrease false-positive biopsy recommendations.

Distinguishing benign from malignant masses at breast US: combined US elastography and color doppler US--influence on radiologist accuracy.

PURPOSE: To investigate the effect of the combined use of ultrasonographic (US) elastography and color Doppler US on the accuracy of radiologists in distinguishing benign from malignant nonpalpable breast masses and in making the decision for biopsy recommendations at B-mode US. MATERIALS AND METHODS: This prospective study was conducted with institutional review board approval; written informed consent was obtained. A cohort of 367 biopsy-proved cases in 319 women (age range, 22-78 years; mean age, 48.6 years) with B-mode US, US elastographic, and Doppler US images was included. Five blinded readers independently scored the likelihood of malignancy for four data sets (ie, B-mode US alone, B-mode US and elastography, B-mode US and Doppler US, and B-mode US, US elastography, and Doppler US). The area under the receiver operating characteristic curve (A(z)) values, sensitivities, and specificities of each data set were compared. RESULTS: The A(z) of B-mode US, US elastography, and Doppler US (average, 0.844; range, 0.797-0.876) was greater than that of B-mode US alone (average, 0.771; range, 0.738-0.798) for all readers (P = .001 for readers 1, 2, and 3; P < .001 for reader 4; P = .002 for reader 5). When both elastography and Doppler scores were negative, leading to strict downgrading, the specificity increased for all readers from an average of 25.3% (75.4 of 298; range, 6.4%-40.9%) to 34.0% (101.2 of 298; range, 26.5%-48.7%) (P < .001 for readers 1, 2, 4, and 5; P = .016 for reader 3) without a significant change in sensitivity. CONCLUSION: Combined use of US elastography and color Doppler US increases both the accuracy in distinguishing benign from malignant masses and the specificity in decision-making for biopsy recommendation at B-mode US.

Differentiating benign from malignant thyroid nodules: comparison of 2- and 3- dimensional sonography.

OBJECTIVES: To compare the diagnostic performance of radiologists and to determine interobserver and intraobserver variability with regard to differentiation of benign and malignant thyroid nodules using prospectively obtained 2-dimensional (2D) and 3-dimensional (3D) sonograms. METHODS: This study had Institutional Review Board approval, and the requirement for patient informed consent was waived. Conventional 2D and 3D sonograms were obtained from 82 patients (age range, 20-77 years; mean age, 51 years) with 91 thyroid nodules (15 cancers, 13 indeterminate, and 63 benign lesions) before diagnostic fine-needle aspiration. Three radiologists reviewed stored 2D and 3D images for internal content, shape, margin, echogenicity, echo texture, and the presence of calcification and estimated the level of suspicion as to the probability of malignancy according to known sonographic criteria. The diagnostic performance of 2D images was compared with that of 3D images. RESULTS: For all readers, interpretation using 3D images was more sensitive and specific than that using 2D images for diagnosis of malignant thyroid nodules, with the exception of specificity for reader 1. However, differences were not statistically significant (P > .05). Area under the receiver operating characteristic curve values were 0.83 for 2D images and 0.92 for 3D images for reader 1; 0.78 for 2D images and 0.89 for 3D images for reader 2; and 0.89 for 2D images and 0.93 for 3D images for reader 3. Interobserver agreement between the 3 radiologists for differentiation of benign and malignant thyroid nodules was better for 3D images (κ = 0.49) than for 2D images (κ = 0.15). Intraobserver variability for nodule descriptions and assessments using 3D and 2D images was fair to moderate. CONCLUSION: The performance of radiologists and interobserver and intraobserver agreement for characterization of thyroid nodules were better when 3D sonograms were used than when 2D sonograms were used.

Aliasing artifact depicted on ultrasound (US)-elastography for breast cystic lesions mimicking solid masses.

BACKGROUND: It has been reported that ultrasound (US)-elastography is helpful in differentiation of benign and malignant solid masses and in reducing benign biopsy procedures for the supplemental breast US in addition to screening mammography. Furthermore, potential application of US-elastography in distinguishing cystic lesions which is known to be a major source of benign biopsy results has been suggested. PURPOSE: To describe the aliasing artifact on US-elastography for breast cystic lesions that mimic solid masses. MATERIAL AND METHODS: We retrospectively reviewed 13 lesions which showed a blue-green-red pattern artifact on US-elastography in 13 women (mean age 50 years; age range 3-66 years). They disappeared immediately after a needle biopsy. Breast composition, mammography and US findings, histology and follow-up imaging findings were analyzed. RESULTS: All 13 patients showed heterogeneously dense (n=5) or extremely dense breast parenchyma (n=8). The most common US findings were an irregular shape (n=7, 54%) and a circumscribed margin (n=7, 54%). All 13 lesions had internal echogenicity and were initially considered as solid masses; 62% (n=8) showed hypoechogenicity and 38% (n=5) had echogenic and anechoic components. Posterior shadowing was seen in 31% (n=4) of the lesions. All 13 lesions have been proven to be fibrocystic changes on biopsy histology. Follow-up US performed for 10 of 13 lesions showed no residual lesion (n=9) or decreased its size (n=1). CONCLUSION: An aliasing artifact that appears as a blue-green-red pattern in a breast mass as depicted on US-elastography is suggestive of a possible cystic breast lesion.

The assessment of breast cancer response to neoadjuvant chemotherapy: comparison of magnetic resonance imaging and 18F-fluorodeoxyglucose positron emission tomography.

BACKGROUND: Neoadjuvant chemotherapy for locally advanced breast cancer is a widely accepted treatment. For assessment of the tumor response after chemotherapy, both magnetic resonance imaging (MRI) and (18)F-fluorodeoxyglucose positron emission tomography (PET) are promising methods. PURPOSE: To retrospectively compare MRI and PET in the assessment of tumor response to neoadjuvant chemotherapy for primary breast cancer with the pathologic response as the reference standard. MATERIAL AND METHODS: Between August 2006 and May 2008, 32 women with breast cancer underwent concurrent MRI and PET before and after neoadjuvant chemotherapy. For response assessment, we calculated the changes in the maximum diameters of the tumor (ΔD(max)) on MRI, and the changes in the standard uptake values (ΔSUV) on PET. The correlation between the ΔD(max) and ΔSUV was analyzed using Pearson's correlation coefficient. The correspondence rates between each imaging modality and pathologic assessment were calculated. For prediction of the pathologic complete response (pCR), the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were analyzed using the McNemar test. RESULTS: The pathologic assessment of tumor response to neoadjuvant chemotherapy identified eight complete responses (25.0%), 10 partial responses (31.2%), and 14 non-responses (43.8%). The change in size on MRI was moderately correlated with the change in SUV on PET (r=0.574, p=0.001). The correspondence rate of response assessment was 75.0% (24/32) between MRI and pathologic response and 53.1% (17/32) between PET and pathologic response. For the pCR, specificity (95.8% vs. 62.5%) and PPV (83.3% vs. 47.1%) were statistically higher on MRI than PET (p < 0.05), while sensitivity (100.0% vs. 62.5%) and NPV (100.0% vs. 88.5%) on PET tended to be higher than MRI. CONCLUSION: Before and after neoadjuvant chemotherapy for breast cancer, the ΔD(max) of MRI correlated moderately with the ΔSUV on PET. For prediction of the pCR, MRI proved to be a more specific modality than PET.

Features of prospectively overlooked computer-aided detection marks on prior screening digital mammograms in women with breast cancer.

OBJECTIVE: The purpose of this article is to describe the features of prospectively overlooked computer-aided detection (CAD) marks on prior screening digital mammograms for women with breast cancer. SUBJECTS AND METHODS: A CAD system embedded in a digital mammography system was prospectively applied to 50,100 screening mammograms between December 2003 and December 2006. Each mammogram was originally interpreted by one of five radiologists using the CAD information. Seventy-five mammogram pairs of prior negative screening mammograms and subsequent mammograms of developed cancers were collected. Visible findings and their actionability were determined by three blinded radiologists. All CAD marks, both true-positive and false-positive, and the number of marked views for the visible findings on prior mammograms were analyzed. RESULTS: Of the 75 areas where cancer later developed, 61% (46/75) of mammograms had visible findings (21 masses, 17 microcalcifications, and eight masses with microcalcifications). Of these visible findings, 46% (21/46) were determined to be actionable, and 54% (25/46) were underthreshold. The CAD system had correctly depicted 74% (34/46) of the visible findings-52% (11/21) of masses, 94% (16/17) of microcalcifications, and 88% (7/8) of masses with microcalcifications. Actionable findings showed higher CAD sensitivity than did underthreshold findings (90% [19/21] vs 60% [15/25]; p = 0.04) and were more often marked on both views (58% [11/19] vs 27% [4/15]; p = 0.09). The average number of false-positive marks per case was 1.61. CONCLUSION: On prior screening digital mammograms, the CAD system had correctly marked 74% (34/46) of visible findings and 90% (19/21) of actionable findings. The actionable findings showed significantly higher CAD sensitivity and were marked on both mammographic views more often than the underthreshold findings were.

Ultrasonography-guided vacuum-assisted biopsy of microcalcifications: Comparison of the diagnostic yield of calcified cores and non-calcified cores on specimen radiographs.

BACKGROUND: Microcalcifications found on mammography of asymptomatic women can be sampled by ultrasound (US)-guided percutaneous breast biopsy when stereotactic core biopsy is unavailable or unsuccessful. The role of specimen radiograph needs to be reevaluated after US-guided biopsy. PURPOSE: To compare retrospectively the histological diagnoses of calcified cores and non-calcified cores as depicted on specimen radiographs after a US-guided, 11-gauge, vacuum-assisted biopsy using surgical histology as the reference standard. MATERIAL AND METHODS: A total of 135 consecutive patients underwent a US-guided vacuum-assisted biopsy for calcifications with malignant histological results from 135 lesions. For each lesion, calcification was identified in at least one core on specimen radiographs. Calcified cores and non-calcified cores depicted on specimen radiographs were separately submitted to the pathology department. The pathological diagnoses of calcified cores and non-calcified cores were compared with final diagnoses at surgical excision. RESULTS: Of a total of 2049 core specimens that were obtained (mean, 15 per lesion; range, 4-35 per lesion), 794 cores (mean, 5.9 per lesion; range, 1-17 per lesion) contained calcifications and 1255 cores (mean, 9.3 cores per lesion; range, 1-34 cores per lesion) did not contain calcifications. Calcified cores were more likely to enable an accurate diagnosis of cancer as compared to non-calcified cores (67%, 91 of 135 versus 52%, 70 of 135; P = 0.009). A diagnosis of cancer was more likely to be missed with non-calcified cores as compared to calcified cores (16%, 21 of 135 versus 4%, 5 of 135; P = 0.002). There was no difference in the underestimation of malignancy between calcified cores (29%, 39 of 135) and non-calcified cores (33%, 44 of 135) (P = 0.510). CONCLUSION: Calcified cores depicted on specimen radiographs are more accurate for a diagnosis of cancer as compared to non-calcified cores obtained during US-guided vacuum-assisted biopsy of microcalcifications.

Sonoelastographic strain index for differentiation of benign and malignant nonpalpable breast masses.

OBJECTIVE: The purpose of this study was to evaluate the diagnostic potential of the sonoelastographic strain index for differentiation of nonpalpable breast masses. METHODS: Ninety-nine nonpalpable breast masses (79 benign and 20 malignant) in 94 women (mean age, 45 years; range, 21-68 years) who had been scheduled for a sonographically guided core biopsy were examined with B-mode sonography and sonoelastography. Radiologists who had performed the biopsies analyzed the B-mode sonograms and provided American College of Radiology Breast Imaging Reporting and Data System categories. The strain index (fat to lesion strain ratio) was calculated by dividing the strain value of the subcutaneous fat by that of the mass. The histologic result from the sonographically guided core biopsy was used as a reference standard. The diagnostic performance of the strain index and that of B-mode sonography were compared by receiver operating characteristic (ROC) curve analysis. RESULTS: The mean strain index values +/- SD were 6.57 +/- 6.62 (range, 1.29-28.69) in malignant masses and 2.63 +/- 4.57 (range, 0.54-38.76) in benign masses (P = .019). The area under the ROC curve values were 0.835 (95% confidence interval [CI], 0.747-0.902) for B-mode sonography and 0.879 (95% CI, 0.798-0.936) for the strain index (P = .490). The sensitivity, specificity, positive predictive value, and negative predictive value were 95% (19 of 20), 75% (59 of 79), 48% (19 of 39), and 98% (59 of 60), respectively, when a best cutoff point of 2.24 was used. CONCLUSIONS: The strain index based on the fat to lesion strain ratio has diagnostic performance comparable with that of B-mode sonography for differentiation of benign and malignant breast masses.

Mammographic and sonographic findings of primary breast lymphoma.

The objective of this study was to describe the mammographic and sonographic appearances of primary lymphoma of the breast. We retrospectively reviewed the mammographic and ultrasonographic images of 12 patients with primary lymphoma of the breast. Descriptions of imaging findings were made according to the Breast Imaging Reporting and Data System lexicon by two radiologists. Mammography was performed on 11 patients. Most of the lesions were shown to be oval-shaped (72.7%) and high-density (90.9%) masses on mammography. Ultrasound examination was performed on 8 patients. The lymphomas were commonly single (75%), circumscribed (50%) or microlobulated (37.5%), and oval (50%) masses on sonography. The echo pattern of the mass was hypoechoic in 7 patients (87.5%) but hyperechoic in 1 patient (12.5%). No mass had spiculated margins or calcifications. Ipsilateral axillary lymph node involvement was noted in 1 patient. In conclusion, most primary lymphomas of the breast present as oval-shaped and high-density masses on mammography and as single and hypoechoic masses with circumscribed or microlobulated margins on sonography.

Comparison of new and established full-field digital mammography systems in diagnostic performance.

OBJECTIVE: To compare the diagnostic performance of new and established full-field digital mammography (FFDM) systems. MATERIALS AND METHODS: During a 15-month period, 1038 asymptomatic women who visited for mammography were prospectively included from two institutions. For women with routine two-view mammograms from established FFDM systems, bilateral mediolateral oblique (MLO) mammograms were repeated using the new FFDM system. One of the four reviewers evaluated two-sets of bilateral MLO mammograms at 4-week intervals by using a five-point score for the probability of malignancy according to a Breast Imaging Reporting and Data System. The lesion type and breast density were determined by the consensus of two readers at each institution. The dichotomized mammographic results correlated with a final pathologic outcome and follow-up data. Receiver operating characteristic (ROC) curves, sensitivity, and specificity were compared in general and according to the lesion type and breast density. RESULTS: Of the 1038 cases, 193 (18.6%) had cancer. The areas under the ROC curve (AUC), sensitivity, and specificity of the established system were 0.815, 65.3%, and 90.2%, respectively. Those of the new system were 0.839, 68.4%, and 91.7%, respectively. There were no significant differences in the AUCs, sensitivities or the specificities in general between new and established systems (Ps = 0.194, 0.590, 0.322, respectively). We found no significant difference in these parameters according to lesion type or breast density. CONCLUSION: The new FFDM system has a comparable diagnostic performance with established systems.

Computer-aided evaluation of breast MRI for the residual tumor extent and response monitoring in breast cancer patients receiving neoadjuvant chemotherapy.

OBJECTIVE: To evaluate the accuracy of a computer-aided evaluation program (CAE) of breast MRI for the assessment of residual tumor extent and response monitoring in breast cancer patients receiving neoadjuvant chemotherapy. MATERIALS AND METHODS: Fifty-seven patients with breast cancers who underwent neoadjuvant chemotherapy before surgery and dynamic contrast enhanced MRI before and after chemotherapy were included as part of this study. For the assessment of residual tumor extent after completion of chemotherapy, the mean tumor diameters measured by radiologists and CAE were compared to those on histopathology using a paired student t-test. Moreover, the agreement between unidimensional (1D) measurement by radiologist and histopathological size or 1D measurement by CAE and histopathological size was assessed using the Bland-Altman method. For chemotherapy monitoring, we evaluated tumor response through the change in the 1D diameter by a radiologist and CAE and three-dimensional (3D) volumetric change by CAE based on Response Evaluation Criteria in Solid Tumors (RECIST). Agreement between the 1D response by the radiologist versus the 1D response by CAE as well as by the 3D response by CAE were evaluated using weighted kappa (k) statistics. RESULTS: For the assessment of residual tumor extent after chemotherapy, the mean tumor diameter measured by radiologists (2.0 ± 1.7 cm) was significantly smaller than the mean histological diameter (2.6 ± 2.3 cm) (p = 0.01), whereas, no significant difference was found between the CAE measurements (mean = 2.2 ± 2.0 cm) and histological diameter (p = 0.19). The mean difference between the 1D measurement by the radiologist and histopathology was 0.6 cm (95% confidence interval: -3.0, 4.3), whereas the difference between CAE and histopathology was 0.4 cm (95% confidence interval: -3.9, 4.7). For the monitoring of response to chemotherapy, the 1D measurement by the radiologist and CAE showed a fair agreement (k = 0.358), while the 1D measurement by the radiologist and 3D measurement by CAE showed poor agreement (k = 0.106). CONCLUSION: CAE for breast MRI is sufficiently accurate for the assessment of residual tumor extent in breast cancer patients receiving neoadjuvant chemotherapy. However, for the assessment of response to chemotherapy, the assessment by the radiologist and CAE showed a fair to poor agreement.

Feasibility of sentinel lymph node biopsy in breast cancer patients with initial axillary lymph node metastasis after primary systemic therapy.

PURPOSE: Primary systemic therapy (PST) downstages up to 40% of initial documented axillary lymph node (ALN) metastases in breast cancer. The current surgical treatment after PST consists of breast tumor resection and axillary lymph node dissection (ALND). This strategy, however, does not eliminate unnecessary ALND in patients with complete remission of axillary metastases. The aim of this study was to examine the accuracy of sentinel lymph node biopsy (SLNB) after PST among patients with documented ALN metastasis at presentation and to identify the rate of pathologic complete-remission (CR) with ALN after PST. METHODS: We analyzed 66 patients with ALN metastasis that was pathologically proven preoperatively who underwent SLNB and concomitant ALND after PST. Axillary ultrasound (AUS) was used to evaluate the clinical response of initially documented ALN metastasis after PST. Intraoperative lymphatic mapping was performed using blue dye with or without radioisotope. RESULTS: After PST, 34.8% of patients had clinical CR of ALN on AUS and 28.8% patients had pathologic CR of ALN. The overall success rate of SLNB after PST was 87.9%, and the sentinel lymph node identification rate in patients with clinical CR was 95.7%. In patients with successful lymphatic mapping, 70.7% of patients had residual axillary metastases. The overall accuracy and false-negative rate were 87.9% and 17.1% in all patients: 95.5% and 10.0% in patients with clinical CR of ALN, and 83.3% and 19.4% in patients with residual axillary disease after PST. CONCLUSION: Our findings suggest that SLNB may be feasible in patients with initial documented ALN metastasis who have clinical CR for metastatic ALN after PST. Further investigation in a prospective setting should be performed to confirm our results.