Shear wave elastography (SWE) is an emerging technique which can obtain quantitative elasticity values in breast disease. We therefore evaluated the diagnostic performance of SWE for the differentiation of breast masses compared with conventional ultrasound (US). Conventional US and SWE were performed by three experienced radiologists for 158 consecutive women who had been scheduled for US-guided core biopsy or surgical excision in 182 breast masses (89 malignancies and 93 benign; mean size, 1.76 cm). For each lesion, quantitative elasticity was measured in terms of the Young's modulus (in kilopascals, kPa) with SWE, and BI-RADS final categories were assessed with conventional US. The mean elasticity values were significantly higher in malignant masses (153.3 kPa ± 58.1) than in benign masses (46.1 kPa ± 42.9), (P < 0.0001). The average mean elasticity values of invasive ductal (157.5 ± 57.07) or invasive lobular (169.5 ± 61.06) carcinomas were higher than those of ductal carcinoma in situ (117.8 kPa ± 54.72). The average mean value was 49.58 ± 43.51 for fibroadenoma, 35.3 ± 31.2 for fibrocystic changes, 69.5 ± 63.2 for intraductal papilloma, and 149.5 ± 132.4 for adenosis or stromal fibrosis. The optimal cut-off value, yielding the maximal sum of sensitivity and specificity, was 80.17 kPa, and the sensitivity and specificity of SWE were 88.8% (79 of 89) and 84.9% (79 of 93). The area under the ROC curve (Az value) was 0.898 for conventional US, 0.932 for SWE, and 0.982 for combined data. In conclusion, there were significant differences in the elasticity values of benign and malignant masses as well as invasive and intraductal cancers with SWE. Our results suggest that SWE has the potential to aid in the differentiation of benign and malignant breast lesions.

Ultrasound (US) is a useful diagnostic tool to distinguish benign from malignant masses of the breast. It is a very convenient and safe diagnostic method. However, there is a considerable overlap benignancy and malignancy in ultrasonic images and interpretation is subjective. A high performance breast tumors computer-aided diagnosis (CAD) system can provide an accurate and reliable diagnostic second opinion for physicians to distinguish benign breast lesions from malignant ones. The potential of sonographic texture analysis to improve breast tumor classifications has been demonstrated. However, the texture analysis is system-dependent. The disadvantages of these systems which use texture analysis to classify tumors are they usually perform well only in one specific ultrasound system. While Morphological based US diagnosis of breast tumor will take the advantage of nearly independent to either the setting of US system and different US machines. In this study, the tumors are segmented using the newly developed level set method at first and then six morphologic features are used to distinguish the benign and malignant cases. The support vector machine (SVM) is used to classify the tumors. There are 210 ultrasonic images of pathologically proven benign breast tumors from 120 patients and carcinomas from 90 patients in the ultrasonic image database. The database contains only one image from each patient. The ultrasonic images are captured at the largest diameter of the tumor. The images are collected consecutively from August 1, 1999 to May 31, 2000; the patients' ages ranged from 18 to 64 years. Sonography is performed using an ATL HDI 3000 system with a L10-5 small part transducer. In the experiment, the accuracy of SVM with shape information for classifying malignancies is 90.95% (191/210), the sensitivity is 88.89% (80/90), the specificity is 92.5% (111/120), the positive predictive value is 89.89% (80/89), and the negative predictive value is 91.74% (111/121).

This study was undertaken to compare the labeling efficiencies of three iron-oxide based MRI contrast agents [Feridex, Resovist and monocrystalline iron oxide (MION)] and to evaluate their effects on the biological properties of human mesenchymal stem cells (hMSCs). The hMSCs were cultivated for 1 and 7 days after 24-h labeling with iron oxide nanoparticles (12.5 microg Fe/mL) in the presence of poly-L-lysine (0.75 microg/mL). The hMSCs were labeled more efficiently with use of Feridex, Resovist as compared to MION. No significant differences were observed in terms of viability and proliferation of labeled hMSCs. The level of Oct-4 mRNA increased in labeled hMSCs at day 1 and the cellular phenotype changed from CD45-/CD44+/CD29+ to CD45low/CD44+/CD29+ at day 7, which closely resembles the phenotype of fresh bone marrow-derived hMSCs. Our study has demonstrated that the Feridex or Resovist is the preferred labeling agent for hMSCs. There was a change in Oct-4 and CD45 expression after labeling.

Fluorescence optical imaging technologies are currently being developed to image specific molecular targets in vivo. Detection technologies range from those providing microscopic detail to whole body imaging systems with potential clinical use. A number of target-specific near-infrared imaging probes have recently been developed to image receptors, antigens, and enzymes. The goal of the current study was to evaluate a new near-infrared (NIR) folate receptor (FR)-targeted imaging probe for its ability to improve detection of FR-positive cancers. We hypothesized that modification of folate would retain receptor affinity in vivo, despite the bulkier NIR fluorochrome, NIR2 (em = 682 nm). Cellular uptake of the NIR conjugates was significantly higher in FR-positive nasopharyngeal epidermoid carcinoma, KB cells, compared to FR-negative human fibrosarcoma, HT1080 cells. When tumors were implanted in vivo, equal-sized KB tumors showed a 2.4-fold higher signal intensity compared to HT1080 tumors (24 h). The maximum signal-to-background ratio (3-fold) was observed at 24 h in KB tumor. Injection of the unmodified NIR2 fluorochrome did not result in persistent contrast increases under similar conditions. Furthermore, tumor enhancement with the NIR2-folate probe persisted over 48 h and was inhibitable in vivo by administration of unlabeled folate. These results indicate that folate-modified NIR fluorochrome conjugate can be used for improved detection of FR-positive tumors.