Subcutaneous Angioleiomyoma: Clinical and Sonographic Features With Histopathologic Correlation.

OBJECTIVES: To investigate clinical and sonographic features of subcutaneous angioleiomyoma with histopathologic correlation. METHODS: Clinical features of 141 cases and sonographic appearances of 33 cases of histopathologically proven subcutaneous angioleiomyoma were retrospectively reviewed. Clinical information included patient age, sex, tumor location, and symptoms. Sonographic features included tumor size, location, contour, margin, component, echogenicity, calcifications, and vascularity. Sonograms were analyzed with histopathologic correlation by a single radiologist and a single pathologist. RESULTS: Clinical features of the 141 cases of angioleiomyoma included the following: 78.0% of the cases (110 of 141) were on the lower leg or ankle; 55.3% of the patients (78 of 141) had pain at the tumor location; the female-to-male ratio was 1.61:1.00, and most cases occurred in patients in the third through sixth decades. Sonographic features of the 33 cases of angioleiomyoma included the following: 85.0% of the cases (28 of 33) were smaller than 20 mm; 94.0% to 97.0% were solid, oval, parallel to the skin, well defined, and homogeneously hypoechoic and without calcifications; 75.8% (25 of 33) were superficially located, close to or in contact with the dermis; and 39.4% (13 of 33) showed low or moderate internal vascularity. CONCLUSIONS: Typical clinical and sonographic features of angioleiomyoma may include a female patient with a painful lower leg or ankle subcutaneous mass, a superficial location, especially in contact with the dermis, a small size (<20 mm), an oval shape, a parallel orientation to the skin, well-defined margins, complete solid components, homogeneous hypoechogenicity, low or moderate vascular density, and absence of calcifications.

Sonographic features of thyroid follicular carcinoma in comparison with thyroid follicular adenoma.

OBJECTIVES: The purpose of this study was to determine the sonographic features of thyroid follicular carcinoma in comparison with thyroid follicular adenoma. METHODS: This retrospective study included 36 pathologically proven follicular carcinomas (5 widely invasive and 31 minimally invasive) and 52 follicular adenomas in 88 patients who underwent thyroid surgery. We analyzed the sonographic features of each tumor, including maximum diameter, peripheral halo, echogenicity, echo texture, calcifications, and nodularity. The frequencies of the sonographic features were compared by χ(2) and Fisher exact tests between follicular adenomas and carcinomas. The relative risk of malignancy was evaluated by logistic regression analysis. RESULTS: Predominantly solid contents, hypoechoic echogenicity, a heterogeneous echo texture, the presence of calcifications, and an absent or irregular thick halo were associated with follicular carcinoma (P < .05). Logistic regression analysis demonstrated that predominantly solid contents, a heterogeneous echo texture, and the presence of calcifications were associated with significant increases in the relative risk of follicular carcinoma (odds ratios, 9.4, 24.9, and 25.6, respectively; P < .01). CONCLUSIONS: Sonography could provide useful information for differentiating follicular carcinoma from follicular adenoma.

Effects of low-frequency ultrasound and microbubbles on angiogenesis-associated proteins in subcutaneous tumors of nude mice.

It has been shown that 1 and 3 MHz low-intensity ultrasound was able to affect the fragile and leaky angiogenic blood vessels in a tumor. However, the biological effects of 21 kHz low-intensity ultrasound on tumors remain unclear. The aim of the present study was to explore the effects of 21 kHz ultrasound with microbubbles on the regulation of vascular endothelial growth factor (VEGF), cyclooxygenase-2 (COX-2) and apoptosis in subcutaneous prostate tumors in nude mice. The study included three parts, each with 20 tumor-bearing nude mice. Twenty nude mice were divided into four groups: control (sham treatment), microbubble ultrasound contrast agent (UCA), low-frequency ultrasound (US) and US+UCA groups. The UCA used was a microbubble contrast agent (SonoVue). The parameter of ultrasound: 21 kHz, an intensity of 26 mW/cm2, 40% duty cycle (on 2 sec, off 3 sec), 3 min, once every other day for 2 weeks. In the first study, all subcutaneous tumors were examined by contrast-enhanced ultrasonography (CEUS) at the initiation and completion of the experiments. Peak intensity (PI), time to peak intensity (TTP) and area under the curve (AUC) on the time intensity curve (TIC) were analyzed. In the second study, the intensity of VEGF and COX-2 protein expression in the vascular endothelium and cytoplasm was evaluated using immunohistochemistry and laser confocal microscopy. In the third study, terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay was used for the evaluation of cell apoptosis in tumor tissues. The tumor cells and vasculature were examined by transmission electron microscopy (TEM). Only in the US+UCA group, PI and AUC decreased. The intensity of COX-2 and VEGF in the US+UCA group in immunohistochemical staining and laser confocal microscopy was lower compared to that of the other three groups. More cell apoptosis was found in the US+UCA group compared to the other 3 groups. In the control, UCA and US groups, the tumors had intact vascular endothelium and vessel lumens in TEM. However, lumen occlusion of vessels was observed in the US+UCA group. Twenty-one kHz low-intensity ultrasound with microbubbles may have anti-angiogenic effects on subcutaneous tumors in nude mice.

Different effects of sonoporation on cell morphology and viability.

The objective of our study was to investigate changes in cell morphology and viability after sonoporation. Sonoportion was achieved by ultrasound (21 kHz) exposure on adherent human prostate cancer DU145 cells in the cell culture dishes with the presence of microbubble contrast agents and calcein (a cell impermeant dye). We investigated changes in cell morphology immediately after sonoporation under scanning electron microscope (SEM) and changes in cell viability immediately and 6 h after sonoporation under fluorescence microscope. It was shown that various levels of intracellular calcein uptake and changes in cell morphology can be caused immediately after sonoporation: smooth cell surface, pores in the membrane and irregular cell surface. Immediately after sonoporation, both groups of cells with high levels of calcein uptake and low levels of calcein uptake were viable; 6 h after sonoporation, group of cells with low levels of calcein uptake still remained viable, while group of cells with high levels of calcein uptake died. Sonoporation induces different effects on cell morphology, intracellular calcein uptake and cell viability.

The improvement of liposome-mediated transfection of pEGFP DNA into human prostate cancer cells by combining low-frequency and low-energy ultrasound with microbubbles.

The aim of this study was to explore the use of a contrast agent to study the effects of exposure to ultrasound, in combination with microbubbles, on liposome-mediated transfection of genes into human prostate cancer cells. A contrast agent was used to study the effects of ultrasound exposure in combination with microbubbles on liposomes, which transfect genes into human prostate cancer cells. The human prostate cancer cell line PC-3 in suspension was exposed to ultrasound with a 20% duty cycle (i.e., 2 sec 'on' time and 8 sec 'off' time) lasting 5 min, with and without ultrasound contrast agent (SonoVue™) using a digital sonifier at a frequency of 21 kHz and an intensity of 4.6 mW/cm2. Immediately after exposure to ultrasound, cell viability and membrane damage were measured. After exposure to ultrasound, the cell suspensions were put into 12­well plates and cultured for 24 h. Fluorescence microscopy and flow cytometry were used to detect pEGFP transfection efficiency. Exposure to ultrasound alone and ultrasound combined with microbubbles resulted in minimal cell death and induced negligible cell membrane damage. Ultrasound combined with microbubbles had a greater effect on cell membrane damage in all groups: the average cell membrane damage was 41.87%, and it was approximately 42­fold greater than in the control group. The average transfection efficiency of PC-3 cells was 20.30% for the liposome (Lipofectamine™)+pEGFP+ultrasound+ultrasound contrast agent (SonoVue) group; this was the highest rate of all groups measured and was approximately 81­fold greater than that of the control group. The use of low-frequency and low-energy ultrasound, in combination with microbubbles, could be a potent physical method for increasing liposome gene delivery efficiency. This technique is a promising non-viral approach that can be used in prostate cancer gene therapy.