C-reactive protein binds to integrin α2 and Fcγ receptor I, leading to breast cell adhesion and breast cancer progression.

C-reactive protein (CRP) is an acute phase protein synthesized upon the inflammatory responses, associated with breast cancer. The process of tumor cell invasion and metastasis involves the adherence of cells to the extracellular matrix via integrin as a receptor for matrix molecules. The present study investigated the role of CRP in the adhesive phenotype of breast cells and the underlying mechanisms. Here, we first showed that CRP induces adhesion of MCF10A human breast epithelial cells through the activation of integrin α2 signaling. Expression of integrin α2 was induced by CRP in which transcription factors c-fos and SP1 may be involved. Binding of CRP with integrin α2 leads to the activation of focal adhesion kinase (FAK), paxillin and ERKs. CRP also binds to an Fcγ receptor Fcγ receptor I (FcγRI), and induces activation of paxillin, FAK and ERKs. Integrin α2 and FAK have crucial roles in the adhesive and invasive phenotypes as well as MMP-9 upregulation induced by CRP in MCF10A cells. Treatment with an inflammatory lipid sphingosine-1-phosphate induced CRP, which may be secreted and exert an autocrine effect by binding to FcγRI and integrin α2. Involvement of CRP in adhesion, invasion, anchorage-independent growth and upregulation of integrin α2, paxillin and FAK was observed in MDA-MB-231 triple-negative human breast cancer (TNBC) cells. Using an in vivo invasion model and an orthotopic mouse tumor model with MDA-MB-231 cells, we showed that CRP has an important role in intravasation and tumor growth in vivo, demonstrating the in vivo relevance of our in vitro results. The present study elucidates a critical molecular basis between CRP, integrin α2 and FcγRI pathways in MCF10A breast cells and MDA-MB-231 TNBC cells, thereby providing useful information on CRP-induced aggressiveness of breast cells in the inflammatory microenvironment.

Clinical benefit of nomogram for predicting positive resection margins in breast conserving surgery.

PURPOSE: Previously, we reported a nomogram for the prediction of positive resection margin (RM) after breast conserving surgery (BCS). This study was conducted to evaluate the clinical usefulness of the nomogram. METHODS: Prospective patients who underwent operations using the nomogram between July 2012 and August 2013 (nomogram group; N = 260) were compared with past control patients who underwent operations between July 2010 and October 2011 and underwent frozen section biopsy (FSB) without use of the nomogram (N = 266). In the nomogram group, an intraoperative assessment of RM using FSB was only performed when the nomogram score was higher than predefined cut-off (>80). In addition, we conducted retrospective analysis of additional 181 patients who received BCS in another institute (Kyoto University Hospital). These patients did not undergo FSBs for RMs. RESULTS: Of 260 patients, 161 (61.9%) presented low nomogram scores and avoided FSB. The surgical decision to use the nomogram did not significantly increase reoperation rate due to positive RM compared with the control FSB group (4.6% vs. 3.8%, p = 0.47). The surgery time was significantly reduced by 18.1% (mean 14.7 min) in nomogram group (p < 0.001). Of 99 nomogram high-score patients, 14 presented with positive RM on FSB and 11 of them avoided reoperation. In the Kyoto cohort, the reoperation rate was significantly lower in low-score patients than in high-score patients (2.7% vs. 11.4%, p < 0.001). CONCLUSIONS: We showed that our nomogram is useful to reduce FSBs without increasing reoperation rate for surgeons who perform routine FSBs. For most surgeons, it can give useful information about the possibility of tumor-positive RMs.

Role of second-look ultrasound examinations for MR-detected lesions in patients with breast cancer.

PURPOSE: To assess the clinical value of second-look ultrasound (US) examination for the evaluation of additional enhancing lesions detected on magnetic resonance (MR) imaging. MATERIALS AND METHODS: Between May 2008 and February 2011, 794 consecutive patients with histologically confirmed breast cancer underwent breast MR imaging. We included 101 patients with 132 additional enhancing breast lesions detected on MR imaging who underwent second-look US.  The imaging features and lesion category according to the Breast Imaging and Reporting and Data System (BI-RADS) were assessed with MR and US imaging, respectively. RESULTS: According to the BI-RADS system, 67 lesions (50.8 %) were classified as category 0, 33 lesions (25.0 %) as category 3, and 32 lesions (24.2 %) as category 4. Of the 67 indeterminate lesions on MR imaging, 34 (50.7 %) were demonstrated on second-look US. 11 of these 34 lesions showed suspicious sonographic features, including 1 lesion that showed malignancy (9.1 %, 1/11). Most of the suspicious lesions on MR imaging (26 of 32 BI-RADS category 4 lesions, 81.3 %) were demonstrated on second-look US, and 17 were malignant (65.4 %, 17/26). Of the 6 BI-RADS category 4 lesions without sonographic correlation, 1 was malignant (16.7 %, 1/6). CONCLUSION: Second-look US examination was useful for evaluating MR-detected lesions in patients with breast cancer.

Age and HER2 expression status affect MRI accuracy in predicting residual tumor extent after neo-adjuvant systemic treatment.

BACKGROUND: Although recent studies suggest high accuracy of breast magnetic resonance imaging (MRI) in predicting residual tumor extent after neo-adjuvant systemic treatment (NST), its use is still controversial. In this study, we aimed to identify predictive factors of MRI accuracy after NST to determine a subgroup of patients in whom the use of MRI provides best additional benefit. MATERIALS AND METHODS: Clinicopathologic and molecular profiles of breast cancer patients were investigated and their relationships with MRI accuracy were analyzed. RESULTS: From January 2006 to February 2008, 195 patients received NST and preoperative MRI. In overall, MRI predicted residual tumor extent with higher accuracy than ultrasonography. Triple-negative (TN) tumors showed highest correlation between MRI-measured and pathologic tumor size (r = 0.781) when compared with other subtypes. Multivariate analysis showed age and HER2 expression status as independent factors predicting MRI accuracy. When patients were classified based on their age and HER2 status, relatively older patients (>45) with HER2-negative tumors showed highest MRI accuracy. This finding was further validated using an independent cohort of 63 consecutive patients. CONCLUSION: Age and HER2 status independently affected MRI accuracy after NST. This observation may guide more tailored approach in using MRI in breast cancer patients undergoing NST.

Computer-aided diagnosis using morphological features for classifying breast lesions on ultrasound.

OBJECTIVES: To develop and evaluate a computer-aided diagnosis (CAD) system with automatic contouring and morphological analysis to aid in the classification of breast tumors using ultrasound. METHODS: We evaluated 118 breast lesions (34 malignant and 84 benign tumors). Each tumor contour was automatically extracted from the digitized ultrasound image. Nineteen practical morphological features from the extracted contour were calculated and principal component analysis (PCA) was applied to find independent features. A support vector machine (SVM) classifier utilized the selected principal vectors to identify the breast tumor as benign or malignant. In this study, all the cases were sampled with k-fold cross-validation (k = 10) to evaluate the performance by receiver-operating characteristics (ROC) curve analysis. RESULTS: The areas under the ROC curves for the proposed CAD systems using all morphological features and the lower-dimensional principal vector were 0.91 and 0.90, respectively. The classification ability for breast tumors using morphological information was good. CONCLUSIONS: This system differentiates benign from malignant breast tumors well and therefore provides a clinically useful second opinion. Moreover, the morphological features are nearly setting-independent and thus available to various ultrasound machines.

Optimal clustering of kinetic patterns on malignant breast lesions: comparison between K-means clustering and three-time-points method in dynamic contrast-enhanced MRI.

Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is useful for breast cancer diagnosis and treatment planning. Nevertheless, due to the multi-temporal nature of DCE-MRI data, the assessment of early stage breast cancer is a challenging task. In this study, we applied an unsupervised clustering approach and cluster validation technique to the analysis of malignant intral-tumoral kinetic curves in DCE-MRI. K-means cluster analysis was performed from real world malignant tumor cases and the data were transformed into an optimal number of reference patterns representative each cluster. The optimal number of clusters was estimated by a cluster validation index, which was calculated with the ratio of inter-class scatter to intra-class scatter. This technique then classifies tumor specific patterns from a given MRI data by measuring the vector distances from the reference pattern set, and compared the result from the k-means clustering with that from three-time-points (3TP) method, which represents a clinical standard protocol for analysis of tumor kinetics. The evaluation of twenty five cases indicates that optimal k-means clustering reflects partitioning intra-tumoral kinetic patterns better than the 3TP technique. This method will greatly enhance the capability of radiologists to identify and characterize internal kinetic heterogeneity and vascular change of a tumor in breast DCE-MRI.

An extract of Polygonum multiflorum protects against free radical damage induced by ultraviolet B irradiation of the skin.

Over the last decades, the incidence of ultraviolet B (UVB)-related skin problems has been increasing. Damages induced by UVB radiation are related to mutations that occur as a result of direct DNA damage and/or the production of reactive oxygen species. We investigated the anti-oxidant effects of a Polygonum multiflorum thumb extract against skin damage induced by UVB irradiation. Female SKH-1 hairless mice were divided into three groups: control (N = 7), distilled water- (N = 10), and P. multiflorum extract-treated (PM, N = 10) groups. The PM (10 g) was extracted with 100 mL distilled water, cryo-dried and 9.8 g was obtained. The animals received a topical application of 500 microL distilled water or PM extract (1, 2, 4, 8, and 16%, w/v, dissolved in distilled water) for 30 min after UVB irradiation (wavelength 280-320 nm, 300 mJ/cm(2); 3 min) of the dorsal kin for 14 days, and skin immunohistochemistry and Cu,Zn-superoxide dismutase (SOD1) activity were determined. SOD1 immunoreactivity, its protein levels and activities in the skin were significantly reduced by 70% in the distilled water-treated group after UVB irradiation compared to control. However, in the PM extract-treated groups, SOD1 immunoreactivity and its protein and activity levels increased in a dose-dependent manner (1-16%, w/v, PM extract) compared to the distilled water-treated group. SOD1 protein levels and activities in the groups treated with 8 and 16%, w/v, PM extract recovered to 80-90% of the control group levels after UVB. These results suggest that PM extract strongly inhibits the destruction of SOD1 by UV radiation and probably contains anti-skin photoaging agents.

An extract of Polygonum multiflorum protects against free radical damage induced by ultraviolet B irradiation of the skin

Over the last decades, the incidence of ultraviolet B (UVB)-related skin problems has been increasing. Damages induced by UVB radiation are related to mutations that occur as a result of direct DNA damage and/or the production of reactive oxygen species. We investigated the anti-oxidant effects of a Polygonum multiflorum thumb extract against skin damage induced by UVB irradiation. Female SKH-1 hairless mice were divided into three groups: control (N = 7), distilled water- (N = 10), and P. multiflorum extract-treated (PM, N = 10) groups. The PM (10 g) was extracted with 100 mL distilled water, cryo-dried and 9.8 g was obtained. The animals received a topical application of 500 æL distilled water or PM extract (1, 2, 4, 8, and 16 percent, w/v, dissolved in distilled water) for 30 min after UVB irradiation (wavelength 280-320 nm, 300 mJ/cm²; 3 min) of the dorsal kin for 14 days, and skin immunohistochemistry and Cu,Zn-superoxide dismutase (SOD1) activity were determined. SOD1 immunoreactivity, its protein levels and activities in the skin were significantly reduced by 70 percent in the distilled water-treated group after UVB irradiation compared to control. However, in the PM extract-treated groups, SOD1 immunoreactivity and its protein and activity levels increased in a dose-dependent manner (1-16 percent, w/v, PM extract) compared to the distilled water-treated group. SOD1 protein levels and activities in the groups treated with 8 and 16 percent, w/v, PM extract recovered to 80-90 percent of the control group levels after UVB. These results suggest that PM extract strongly inhibits the destruction of SOD1 by UV radiation and probably contains anti-skin photoaging agents.

Effects of supplementation of beta-glucans on growth performance, nutrient digestibility, and immunity in weanling pigs.

Two experiments were conducted to evaluate the efficacy of beta-glucan on growth performance, nutrient digestibility, and immunity in weanling pigs. In Exp. 1, 210 weanling pigs (6.38 +/- 0.92 kg of BW) were fed dietary beta-glucan (0, 0.01, 0.02, 0.03, or 0.04%) for 5 wk. In Exp. 2, 168 pigs (6.18 +/- 1.31 kg of BW) were fed no beta-glucan or antibiotics (T1), 0.02% beta-glucan (T2), only antibiotics (T3), or 0.02% beta-glucan with antibiotics (T4) for 8 wk. In Exp. 2, the antibiotics fed were apramycin and carbadox in phase I (0 to 2 wk) and carbadox and chlortetracycline in phase II (3 to 8 wk). During Exp. 2, the performance study was conducted for 5 wk, and the immune response was tested until 8 wk. In Exp. 1, there was a trend for a linear increase (P = 0.068) in ADG as the dietary beta-glucan concentration increased in the diet. The digestibilities of DM, GE, CP, ether extract, Ca, and P increased linearly (P < 0.05) in the beta-glucan-supplemented pigs. In Exp. 2, the overall ADG was greater (P < 0.05) in treatment T4 compared with the control group (T1). Also, except for P, this group showed greater (P < 0.05) nutrient digestibilities than the control group. In Exp. 2, at d 15, 24, and 46 antibody titers were measured by ELISA against Pasteurella multocida type A and D after vaccination with atrophic rhinitis, and they differed significantly (P < 0.05) with no particular trend. Flow cytometry was used to determine porcine lymphocyte subpopulations at 4 and 8 wk of Exp. 2. There was an increase in CD4 cells (P < 0.05) and a trend for an increase in CD8 cells (P < 0.10) at 8 wk in pigs fed the T2 diet compared with the other groups. Overall, increasing the dietary concentrations of beta-glucan did not improve ADG without antibiotic, and in weanling pigs antibiotics seem to be more effective in improving nutrient digestibilities and growth performance than beta-glucan.

Effects of supplementation of beta-glucan on the growth performance and immunity in broilers.

Two experiments were conducted to evaluate the efficacy of beta-glucan on commercial broilers. In experiment 1, one hundred and forty-four broiler chicks were employed in a 2x3 factorial design with cage and open floor housing with three levels of beta-glucan viz. 0%, 0.02% and 0.04%. In experiment 2, ninety-six broilers were used with 4 treatments: No beta-glucan and antibiotic (T1), beta-glucan 0.03% (T2), antibiotic (T3), and beta-glucan 0.03% + antibiotic (T4) for 34 d with 3 replicates of 8 chicks each in both studies. During experiment 1 there was no significant effect of the feeding system or the beta-glucan levels on the performance from 0 to 17 d but during 18-34 days birds housed on the open floor had significantly (p<0.0001) higher weight gain compared with those in cages. In experiment 2, no significant effect was noticed on the weight gains when the effect of beta-glucan, antibiotic or their interaction were tested. The retention of dry matter increased in both experiments with beta-glucan supplementation. The CD8 and TCR 1 cells were significantly higher in the 0.04% beta-glucan group at 42 days as compared with the control. It could be concluded that beta-glucan supplementation was beneficial for broilers.

Image retrieval with principal component analysis for breast cancer diagnosis on various ultrasonic systems.

OBJECTIVES: We present a computer-aided diagnostic (CAD) system with textural features and image retrieval strategies for classifying benign and malignant breast tumors on various ultrasonic systems. Effective applications of CAD have used different types of texture analysis. Nevertheless, most approaches performed in a specific ultrasonic machine do not indicate whether the technique functions satisfactorily for other ultrasonic systems. This study evaluated a series of pathologically proven breast tumors using various ultrasonic systems. METHODS: Altogether, 600 ultrasound images of solid breast nodules comprising 230 malignant and 370 benign tumors were investigated. All ultrasound images were acquired from four diverse ultrasonic systems. The suspicious tumor area in the ultrasound image was manually chosen as the region-of-interest (ROI) subimage. Textural features extracted from the ROI subimage are supported in classifying the breast tumor as benign or malignant. However, the textural feature always behaves as a high-dimensional vector. In practice, high-dimensional vectors are unsatisfactory at differentiating breast tumors. This study applied the principal component analysis (PCA) to project the original textural features into a lower dimensional principal vector that summarized the original textural information. The image retrieval techniques were employed to differentiate breast tumors, according to the similarities of the principal vectors. The query ROI subimages were identified as malignant or benign tumors according to characteristics of retrieved images from the ultrasound image database. RESULTS: Using the proposed CAD system, historical cases could be directly added into the database without a retraining program. The area under the receiver-operating characteristics curve for the system was 0.970+/-0.006. CONCLUSION: The CAD system identified solid breast nodules with comparatively high accuracy in the different ultrasound systems investigated.

Microcalcification detection in 3-d breast ultrasound.

The appearance of cluster of microcalcifications in mammography or sonography is an important indicator for malignancy. Microcalcifications are calcium deposits, which can be identified as tiny areas that are slightly brighter than surrounding tissue. Detection of mammographic microcalcification has been proposed in many studies. Since a microcalcification cluster is a three-dimensional (3-D) entity, its projection onto a two-dimensional (2-D) image results in a loss of spatial information and may also cause superimposition of individual calcifications within the cluster. This paper aims to use the 3-D ultrasound to determine microcalcifications. In each slice, the proposed method adopts the top-hat filter to find bright spots, and employs four 2-D criteria to select the spots as candidate microcalcifications. Finally, spots appearing in sequent slices at the same position are considered as a microcalcification. We suggest using a computer automatically to detect the microcalcification being feasible and microcalcifications being a very important criterion of malignancy on future developing the computer-aided diagnosis for ultrasound. In the future, this technique can be adopted in a computer-aided diagnosis system combined with other diagnosis features for improving the diagnosis performance.

Antiviral effect of Saccharomyces cerevisiae beta-glucan to swine influenza virus by increased production of interferon-gamma and nitric oxide.

The aim of these experiments was to investigate the potential antiviral effect of Saccharomyces cerevisiae beta-glucan on the pneumonia induced by swine influenza virus (SIV). Forty colostrum-deprived 5-day-old piglets were randomly divided into four groups of 10. The 20 pigs in groups 1 and 2 were administered Saccharomyces cerevisiae beta-glucan orally (50 mg/day/pig; En-Bio Technology Co., Ltd) for 3 days before SIV infection and those in groups 3 and 4 were given culture medium/diluent alone. Groups 1 and 3 were inoculated intranasally with 3 ml of tissue culture fluid containing 2 x 10(6) tissue culture infective doses 50% (TCID(50))/ml of SIV and those in groups 2 and 4 were exposed in the same manner to uninfected cell culture supernatant. The microscopic lung lesions induced by SIV infection (group 1 pigs) were significantly more severe than those induced by infection in animals pre-administered beta-glucan (group 3) (P < 0.05). Significantly more SIV nucleic acid was detected in the lungs of pigs experimentally infected with SIV only (group 1) at 5, 7 and 10 days post-inoculation (dpi) compared with lungs from pigs pre-administered beta-glucan and infected with SIV (group 3) (P < 0.05). The concentrations of interferon-gamma (IFN-gamma) and nitric oxide (NO) in bronchoalveolar lavage fluid from pigs pre-administered beta-glucan and infected with SIV (group 3) were significantly higher than for any other group at 7 and 10 dpi for IFN-gamma, and at 5, 7 and 10 dpi for NO (P < 0.05). Saccharomyces cerevisiae beta-glucan reduced the pulmonary lesion score and viral replication rate in SIV-infected pigs. These findings support the potential application of beta-glucan as prophylactic/treatment agent in influenza virus infection.

Comparison of contrast-enhanced ct angiography and gadolinium-enhanced MR angiography in the detection of subsegmental-sized pulmonary embolism. An experimental study in a pig model.

PURPOSE: To compare contrast-enhanced CT angiography (CTA) and gadolinium-enhanced MR angiography (MRA) for the detection of subsegmental-sized pulmonary emboli in a pig model. MATERIAL AND METHODS: In 5 anesthetized pigs, 3-mm diameter embolic materials made of Konjac, a semisolid food, were introduced through the internal jugular vein into pulmonary arteries. After embolization, CTA and MRA images were obtained. Respiration was suspended during CTA and MRA image acquisition. Two readers reviewed the CTA and MRA images to detect emboli. The pigs were sacrificed, and sliced specimens of inflated lung served as the gold standard. RESULTS: Thirty-six emboli were detected within peripheral arteries. The sensitivity (and 95% confidence intervals) of CTA for the two readers were 57% (39-74%) and 66% (48-81%), and 88% (69-98%) and 92% (74-94%) for MRA. The specificity of CTA was 95% (91-97%) and 98% (96-99%), and that of MRA was 85% (74-93%) and 90% (80-96%). Interobserver agreement was higher for MRA (kappa 0.898) than CTA (kappa 0.574). CONCLUSION: For the detection of subsegmental pulmonary emboli, MRA was superior to CTA, with a higher sensitivity and interobserver agreement by demonstrating perfusion deficits.

Fluorodeoxyglucose positron emission tomography for detection of recurrent or metastatic breast cancer.

Fluorodeoxyglucose-positron emission tomography (FDG-PET) is a noninvasive imaging technique capable of identifying primary tumors and metastases with high sensitivity and accuracy. The aim of this study was to evaluate the diagnostic accuracy of whole-body FDG-PET imaging for the detection of recurrent or metastatic breast cancer after surgery. Whole-body FDG-PET imaging was performed on 27 patients with suspected recurrent breast carcinoma. PET images were evaluated qualitatively for each patient and lesion. FDG-PET scans showed that there were 61 reference sites of malignant or benign lesions in 27 patients. In a patient-based analysis, FDG-PET scans correctly identified 16 of 17 patients with recurrent or metastatic disease and 8 of 10 without recurrence, resulting in a sensitivity, specificity, and accuracy of 94%, 80%, and 89%, respectively. In a lesion-based analysis, FDG-PET scans correctly identified 46 of 48 lesion sites with recurrent or metastatic disease and 11 of 13 without recurrence. The overall sensitivity, specificity, and accuracy for all lesion sites were 96%, 85%, and 93%, respectively. FDG-PET scans revealed unsuspected recurrent or metastatic diseases in 8 of 27 (30%) of patients and 11 of 20 (55%) distant metastatic lesions. In 13 patients treatment was altered by the outcome of the PET scan. We concluded that whole-body FDG-PET scan is a useful diagnostic imaging modality for detecting recurrent or metastatic breast carcinoma in patients suspected of having recurrent disease after primary surgery.

US of mammographically detected clustered microcalcifications.

PURPOSE: To determine whether ultrasonography (US) can depict breast masses associated with mammographically detected clustered microcalcifications and whether the visibility at US is different between benign and malignant lesions. MATERIALS AND METHODS: Ninety-four patients with 100 mammographically detected microcalcification clusters prospectively underwent US with a 10- or 12-MHz transducer before mammographically guided presurgical hook-wire localization. The visibility of breast masses at US was correlated with histologic and mammographic findings. RESULTS: Surgical biopsy revealed 62 benign lesions, 30 intraductal cancers, and eight invasive cancers. At US, breast masses associated with microcalcifications were seen in 45 (45%) of 100 cases. US depicted more breast masses associated with malignant (31 [82%] of 38) than with benign (14 [23%] of 62) microcalcifications (P: <.001). In malignant microcalcification clusters larger than 10 mm, US depicted associated breast masses in all 25 cases. There was no statistically significant difference in shape and distribution of calcific particles, as well as in breast composition, at mammography between US visible and invisible groups. CONCLUSION: Given a known mammographic location, US with a high-frequency transducer can depict breast masses associated with malignant microcalcifications, particularly clusters larger than 10 mm. US can be used to visualize large clusters of microcalcifications that have a very high suspicion of malignancy.

Nonpalpable breast lesions: evaluation with power Doppler US and a microbubble contrast agent-initial experience.

PURPOSE: To evaluate power Doppler ultrasonography (US) performed with a microbubble US contrast agent in the differentiation of nonpalpable breast lesions. MATERIALS AND METHODS: Fifty nonpalpable breast lesions in 50 patients were prospectively evaluated with power Doppler US before and after injection of the contrast agent SH U 508A. Lesion vascularity and the morphology of vessels on US scans were analyzed and were correlated with histologic results. RESULTS: Surgical excision revealed 22 cancers and 28 benign lesions. At nonenhanced power Doppler US, eight (36%) of 22 cancers and four (14%) of 28 benign lesions were vascular. At contrast agent-enhanced power Doppler US, 21 (95%) cancers and six (21%) benign lesions were vascular (P <.001). Irregular vessels were seen in three cancers and one benign lesion at nonenhanced power Doppler US and in 11 cancers and one benign lesion at contrast-enhanced power Doppler US. By using the presence of vascularity in the mass as the diagnostic criterion for malignancy, the sensitivity, specificity, and positive and negative predictive values of power Doppler US changed from 36%, 86%, 67%, and 63%, respectively, to 95%, 79%, 78%, and 96% after contrast agent injection. CONCLUSION: Contrast-enhanced power Doppler US was superior to nonenhanced power Doppler US in the demonstration and characterization of tumor vascularity in nonpalpable breast lesions. Contrast-enhanced power Doppler US may be useful for the differentiation between nonpalpable breast cancers and benign tumors.

Lesion characterization using vessel permeability map to new blood pool contrast agent calculated from dynamic magnetic resonance images.

Use of contrast enhancement in conjunction with magnetic resonance (MR) imaging provides a means to evaluate tissue function, as well as morphology. Moreover, physiologic properties derived from kinetic analysis of dynamic contrast-enhanced data can improve the specificity of MR examinations. In this study, quantitative analysis of microvascular characteristics based on dynamic MR imaging were performed both for malignant and benign lesions using two types of contrast agents (CAs). A new MR macromolecular contrast medium (MMCM), 24 gadolinium-tetraazacyclododecanetetraacetic acid (DOTA)-dendrimer, was found to have a greater ability to distinguish benign from malignant lesions. When a blood pool agent was used, permeability differences in the two types of lesions were the most significant findings among all parameters considered.

Dynamic contrast-enhanced MR imaging of bacterial abscess and VX2 carcinoma in rabbits: comparison of gadopentetate dimeglumine and a macromolecular contrast agent.

OBJECTIVE: The objective of this study was to compare enhancement patterns of a blood-pool contrast agent, Gadomer-17, with those of gadopentetate dimeglumine in bacterial abscesses and VX2 carcinoma in rabbits. MATERIALS AND METHODS: Fourteen rabbits with experimentally induced bacterial abscesses and VX2 carcinoma in both thighs underwent dynamic contrast-enhanced MR imaging with Gadomer-17 and gadopentetate dimeglumine at a 24-hr interval. The enhancement ratios (postcontrast to precontrast signal intensities) of lesions in the same animal were assessed and correlated with microvessel density. RESULTS: For Gadomer-17, the enhancement ratio of the abscesses (1.66 +/- 0.39) peaked 15 min after the injection, while that of the carcinoma (2.05 +/- 0.16) peaked at 10 min. The enhancement ratios of the carcinoma were consistently higher than those of the abscesses up to 30 min. For gadopentetate dimeglumine, peak enhancement ratio of the abscesses (2.30 +/- 0.75) was seen 5 min after the injection, while that of the carcinoma (2.32 +/- 0.51) was seen at 3 min. The enhancement ratios of the carcinomas were significantly higher at 1 min, but significantly lower at 20-30 min, compared with those of the abscesses, as a result of rapid decrease of enhancement ratios in the carcinomas. The microvessel density was 9.8 +/- 5.2 vessels per field of view for the abscesses and 36.3 +/- 9.5 vessels per field of view for the carcinoma (p < 0.001). CONCLUSION: Delayed peak enhancement and slow decay were found in both bacterial abscess and VX2 carcinoma with Gadomer-17, whereas early peak enhancement and rapid decay were found especially in VX2 carcinoma with gadopentetate dimeglumine. Enhancement ratios on MR imaging with a blood-pool contrast agent correlated well with the microvessel density in bacterial abscess and VX2 carcinoma.

Metastatic tumors to the breast: mammographic and ultrasonographic findings.

We evaluated the mammographic (n = 16) and ultrasonographic (n = 15) findings of 18 patients with metastatic breast carcinoma. Fifteen patients showed multiple or diffuse lesions and three patients showed single lesions. Ten patients (55.6%) had bilateral lesions. Mammography revealed high density (15 cases, 93.8%), round to oval (11 cases, 68.8%) lesions with poorly defined or obscured margins (12 cases, 75.0%). No associated calcification was found in any lesion. Ultrasonographically, poorly defined (8 cases, 53.3%), irregularly shaped (8 cases, 53.3%), hypoechoic (14 cases, 93.3%), heterogeneous (8 cases, 53.3%) lesions were predominantly distributed superficially (11 cases, 73.3%). Axillary lymphadenopathy was detected in six patients (33.3%). The longest diameter of most of the lesions was less than 2.0 cm (13 cases, 81.3%). We conclude that metastatic tumors to the breast appear as relatively small, superficially located, poorly defined, irregular nodules without calcification on mammography and ultrasonography. However, when the metastatic lesion is diffuse, the appearance is indistinguishable from that of inflammatory breast carcinoma.