Vascularity Of Hepatocellular Carcinoma Research Articles

Comparison of MicroFlow Imaging with color and power Doppler imaging for detecting and characterizing blood flow signals in hepatocellular carcinoma.

PurposeThe purpose of this study was to compare the sensitivity of MicroFlow Imaging (MFI) with that of color and power Doppler imaging (CDI and PDI, respectively) in detecting the vascularity of hepatocellular carcinomas (HCCs).MethodsThis prospective study enrolled 51 patients diagnosed with HCC between August 2018 and December 2018. CDI, PDI, MFI, and contrast-enhanced ultrasound (CEUS) were performed. Two radiologists evaluated the presence and pattern of tumoral vascularity on CDI, PDI, and MFI. Vascular presence was graded on a 5-point scale (0, absent; 4, >50% of the tumor). The vascular pattern was chosen from following categories: basket, vessels in tumor, spot, detouring, mixed, or others. Two additional radiologists assessed CEUS images for the presence and pattern of tumoral vascularity, which served as the reference standard. If the tumoral vascular pattern on each examination matched that of the CEUS images, the Wilcoxon test and McNemar test, respectively, were used to compare the sensitivity for detecting tumoral vascularity between MFI and CDI, and between MFI and PDI. Logistic regression analysis was performed to identify factors associated with MFI detectability of tumoral vascularity.ResultsCEUS demonstrated tumoral vascularity in 98.0% (50 of 51) of patients. MFI (58.0%, 29 of 50) demonstrated a higher sensitivity than CDI (14.0%, 7 of 50) or PDI (14.0%, 7 of 50) (P<0.001 for both) in detecting tumoral vascularity, provided that the vascular pattern was correctly depicted. Only tumor depth was associated with the MFI detectability of tumoral vascularity.ConclusionThe sensitivity of MFI was higher than that of CDI or PDI in detecting the vascularity of HCCs when the vascular pattern was considered. MFI better detected the vascularity of shallow tumors.

Role of contrast-enhanced ultrasound in the evaluation of vascularization of hepatocellular carcinoma

Role of contrast-enhanced ultrasound in the evaluation of vascularization of hepatocellular carcinoma

Contrast-enhanced susceptibility weighted imaging with ultrasmall superparamagnetic iron oxide improves the detection of tumor vascularity in a hepatocellular carcinoma nude mouse model.

To evaluate the effectiveness of contrast-enhanced susceptibility-weighted imaging with ultrasmall superparamagnetic iron oxide (USPIO-enhanced SWI) in the assessment of intratumoral vascularity in hepatocellular carcinoma (HCC). Orthotopic xenograft HCC nude mouse models were established first and magnetic resonance imaging (MRI) examinations were performed on a 1.5T MR scanner 28 days later. Three groups of mice, 10 in each, were imaged using unenhanced and USPIO-enhanced SWI at doses of 4, 8, and 12 mg Fe/kg. Intratumoral susceptibility signal intensity (ITSS) was scored. ITSS-to-tumor contrast-to-noise ratio (ITSST-CNR) was measured. These measurements were compared between unenhanced and USPIO-enhanced SWI at each dose and differences in the measurements between different dose groups were estimated. Correlation between ITSS and tumor microvessel density (MVD) was analyzed. Compared with unenhanced SWI, significantly higher ITSS was identified on USPIO-enhanced SWI at doses of 8 mg Fe/kg (Z = -2.000, P = 0.046) and 12 mg Fe/kg (Z = -2.333, P = 0.020). Significantly higher ITSST-CNR was found on USPIO-enhanced SWI than that on unenhanced SWI (P < 0.05). Significantly higher ITSST-CNR at a dose of 8 mg Fe/kg was observed than that at 4 mg Fe/kg (Z = -3.326, P = 0.001). Positive correlation between ITSS on USPIO-enhanced SWI at a dose of 8 mg Fe/kg and tumor MVD was demonstrated (r = 0.817, P = 0.004). USPIO-enhanced SWI at a dose of 8 mg Fe/kg greatly improves the detection of intratumoral vascularity in a xenograft HCC model. J. Magn. Reson. Imaging 2016;44:288-295.

Quantitative Assessment of Tissue Perfusion in Hepatocellular Carcinoma Using Perflubutane Dynamic Contrast-Enhanced Ultrasonography: A Preliminary Study.

Our purpose in this study was to assess the relationship between contrast signal intensity (CI) and concentration of perflubutane microbubbles in a phantom experiment, and to examine the feasibility of this technique for quantitative analysis of vascularity in hepatocellular carcinoma (HCC). Microbubble solutions of the perflubutane contrast agent were prepared by mixing with purified water. We examined the relationship between CI in dB units and the concentration. Moreover, seven HCC patients were examined using real-time dynamic contrast imaging. The perfusion index was calculated from time-intensity curves generated for both HCC and surrounding liver parenchyma. We observed a linear relationship between the CIdB and the concentration in the phantom study and a higher perfusion index in the HCC lesions relative to the surrounding liver parenchyma. Dynamic contrast-enhanced ultrasonography with perflubutane microbubbles, which exhibit linear and temporally stable characteristics under continuous ultrasound exposure, allows the collection of quantitative hemodynamic information regarding HCC.

Vascularization of hepatoceliular carcinoma

The paper gives the data available in the literature on vascularization of hepatocellular carcinoma (HCC). Sinusoidal capillarization and unpaired arteries are shown to play an important role in the development and progression of HCC. The density of microvessels detected by immunohistochemical techniques is a morphological indicator of the degree of angiogenic processes. Higher-grade HCC is followed by changes in its vascularization and concurrent with a progressive increase in the proportion of blood entering along the hepatic artery. The morphological indicators of microvessel density are recommended to use as addi- tional criteria for determining the prognosis of the disease, designing targeted anti-angiogenic drugs, and evaluating the efficiency of performed therapy.

The relationship between the percentage of lung shunting on Tc-99m macroaggregated albumin (Tc-99m MAA) scan and the grade of hepatocellular carcinoma vascularity

BackgroundHepatocellular carcinoma (HCC) stands for the majority of primary liver malignancy. HCC has variable grade of vascularity according to the histological tumor grade and underlying liver damage. Yttrium-90 radioembolization is a promising catheter-based hepatic intra-arterial therapy for HCC that necessitates proper planning. Technetium-99m macroaggregated albumin (Tc-99m MAA), a simulation of the treatment, is used to identify the shunting of microspheres to the lungs or gastrointestinal tract. ObjectiveTo evaluate the relationship between the percentage of lung shunting on Tc-99m MAA scan performed in treatment planning of Yttrium-90 (Y-90) microsphere selective internal radiation therapy (SIRT) for HCC and the grade of tumor vascularity shown on digital subtraction hepatic angiography. Materials and methodsThis study was conducted on 19 patients diagnosed to have HCC, based on typical computed tomography (CT) criteria and/or elevated alpha-fetoprotein (AFP) ⩾200ng/ml, and planned for Y-90 therapy. They were injected by Tc-99m MAA into the hepatic arterial territory with prior digital subtraction angiography. Tc-99m MAA scan was reviewed for extrahepatic shunting within the abdomen. Additionally, the hepatopulmonary shunt (HPS) fraction or the lung shunting (LS) percentage was calculated and further evaluated in relation to the grade of tumor vascularity shown on digital subtraction hepatic angiography. ResultsThere was no extrahepatic accumulation of Tc-99m MAA related to umbilical, gastroduodenal or splenic shunting. The LS percentage assorted among patients and ranged between 0.8% and 42.9% with a median of 5.5%. LS more than 20% occurred in only 1 patient. Subsequent therapy plan was changed accordingly in 5% of patients. The more vascular the lesion was, the higher lung shunting percentage was detected. ConclusionTc-99m MAA scan is fundamental prior to Y-90 microsphere SIRT as it minimizes the risk of post-radioembolization complications, hence, enhancing the safety of Y-90 microsphere subsequent administration. Moreover, the percentage of lung shunting varies considerably among patients with HCC relying on the grade of tumor vascularity.

Spiral computed tomography angiography in the evaluation of hepatocellular carcinoma vascularity and malignancy degree

Aim. To study the vascularity and malignancy degrees of hepatocellular carcinoma using spiral computed tomography angiography considering its morphological differentiation and tumor size. Methods. A comprehensive clinical and radiological examination of 300 patients (males - 170 (56.6%), females - 130 (43.4%), mean age 52.0±3.2 years) with hepatocellular carcinoma, who were picked out from 2550 patients with malignancies treated in 2005-2013, was performed. Liver cirrhosis was diagnosed in 70 (23.33%) out of 300 patients with hepatocellular carcinoma. The features of tumor bloodflow were assessed using color Doppler ultrasonography and spiral computed tomography angiography (by 4 phases of examination) considering tumor size and tumor morphological differentiation. Results. According to the morphological study results of samples from 123 patients, high-grade differentiated hepatocellular carcinoma was diagnosed in 40 patients, moderately differentiated - in 53, poorly differentiated - in 30 patients. A correlation of tumor vascularity with histological differentiation degree and tumor size was revealed. The difference in high-grade differentiated hepatocellular carcinoma maximal computed tomography density increment gradients at arterial phase compared to liver parenchyma maximal computed tomography density increment was 17 Hounsfield units in tumors sized up to 5 cm and 12 Hounsfield units in 32 (80%) of 40 patients with tumors sized over 5 cm. Thus, high-grade differentiated hepatocellular carcinoma was associated with increased vascularity in 80.0%, normal vascularity - in 8.0%, low vascularity - in 12.0% of cases. The difference in moderately differentiated hepatocellular carcinoma computed tomography density increment gradients compared to liver parenchyma was assessed as 20 and 25 Hounsfield units in tumors with the corresponding size in 45 (89.4%) out of 53 patients. Moderately differentiated hepatocellular carcinoma was associated with increased vascularity in 89.4%, normal vascularity - in 4.0%, low vascularity - in 6.6% of cases. Poorly differentiated hepatocellular carcinoma was associated with increased vascularity only in 7 out of 30 patients. Conclusion. The correlation of tumor vascularity with histological differentiation degree and tumor size was revealed. Increased vascularity was observed in high-grade differentiated and moderately differentiated hepatocellular carcinoma, low vascularity - mainly in poorly differentiated hepatocellular carcinoma.

Thalidomide in advanced hepatocellular carcinoma as antiangiogenic treatment approach: a phase I/II trial

The high vascularity of hepatocellular carcinoma (HCC) seems to be a potential therapeutic target. We evaluated the efficacy, toxicity, and histologic response to thalidomide in advanced HCC in a single center phase I/II pilot trial. Between September 2000 and August 2004 patients with HCC uneligible for any established therapy were enrolled in the study. The initial thalidomide dosage of 100 mg/day was escalated in 100 mg steps weekly up to 300 mg/day based on tolerability. Discontinuation and dose reduction were based on toxicity. Tumor biopsies were scheduled to assess tumor microvessel density and serum levels of angiogenic factors, vascular endothelial growth factor, basic fibroblast growth factor, and endostatin were determined. Twenty-eight patients with histologically proven HCC were entered into this study. The median maximum-tolerated dose of thalidomide was 300 mg/day. Most common toxicities were fatigue (75%), dizziness (64%), nausea (43%), and constipation (39%). Two patients had stable disease for 2.6 and 5.4 months, the remaining 26 patients had disease progression. The median overall survival was 5.1 months. Well preserved liver function was associated with longer overall survival on univariate analysis (P=0.0279). The serum concentrations of vascular endothelial growth factor and endostatin increased significantly (P=0.039 and P=0.024, respectively) after 3 months of thalidomide treatment. No clear differences were observed between the serum basic fibroblast growth factor concentrations at study entry and after 3 months (P=0.983). Microvessel density did not decrease significantly during thalidomide therapy (P=0.109). Thalidomide is moderately tolerated and minimally effective in large HCC.

Dual inhibition of Raf and VEGFR2 reduces growth and vascularization of hepatocellular carcinoma in an experimental model

Activation of the mitogen-activated protein kinase-extracellular-signal-regulated kinase (ERK) pathways plays an important role in the progression of hepatocellular carcinoma (HCC). Importantly, Raf kinases are principal effectors within this oncogenic signaling cascade. We hypothesized that concomitant inhibition of Raf and vascular endothelial growth factor receptor 2 (VEGFR2) will affect tumor growth and angiogenesis of HCC. Human HCC cell lines, endothelial cells (EC), and vascular smooth muscle cells (VSMC) were used. For blocking Raf kinase and VEGFR2, the small molecule inhibitor NVP-AAL881 (Novartis, USA) was used. Activation of signaling intermediates was assessed by Western blotting, and changes in cell motility were evaluated in migration assays. Effects of NVP-AAL881 on HCC growth were determined in a subcutaneous tumor model. NVP-AAL881 disrupted activation of ERK and STAT3 in HCC cells and reduced cancer cell motility. In addition, the migration of ECs and VSMC was also significantly impaired. In ECs, HCC-conditioned media-induced activation of STAT3 was diminished by NVP-AAL881 treatment. In vivo, NVP-AAL881 significantly reduced tumor growth, CD31-vessel area, and numbers of BrdU-positive proliferating tumor cells. Combined inhibition of Raf and VEGFR2 disrupts oncogenic signaling and efficiently reduces tumor growth and vascularization of HCC. Hence, this strategy could prove valuable for therapy of HCC.

Contrast-Enhanced Ultrasonography for Assessment of Tumor Vascularity in Hepatocellular Carcinoma

Studies have shown that angiogenesis is a critical factor for tumor growth and metastasis in a variety of human tumors. Although various methods have been tried to assess vessels in tumors, including microvessel density (MVD), assessment of tumor vessels by radiologic techniques is not well established. The aim of this study was to investigate the efficacy of contrast-enhanced ultrasonography (CEUS) in determining the tumor vascularity of hepatocellular carcinoma (HCC). Contrast-enhanced ultrasonography was done in 50 patients with HCC, which was shown histopathologically through subsequent hepatic resection. A contrast pulse sequencing technique and quantitative auto-tracking contrast quantification software were used to analyze the peak intensity (PI) of HCC. Immunohistochemistry was performed to evaluate the level of MVD in HCC. Then the relationship between PI and the level of MVD was analyzed. The mean PIs of HCC and peripheral tissue +/- SD were 135.19 +/- 28.16 and 72.91 +/- 19.22 dB, respectively. The MVDs of HCC and peripheral tissue were 43.44 +/- 12.22 and 17.14 +/- 9.18, respectively. The values of PI and MVD of HCC were significantly higher than those of peripheral tissue. A significant correlation was found between PI and MVD in HCC tissues (P < .05). The PI in CEUS could reflect the MVD in HCC. Therefore, quantification of CEUS seems to be helpful for assessment of tumor vascularity in HCC.

Comparison of contrast-enhanced harmonic ultrasonography and power Doppler ultrasonography for depicting vascularity of hepatocellular carcinoma identified by angiography-assisted CT

The sensitivity of contrast-enhanced harmonic gray scale imaging was compared with that of power Doppler sonography in depicting tumor vascularity and contrast enhancement of hepatocellular carcinoma (HCC) identified by angiography-assisted computed tomography (CT). One hundred thirty-nine classic HCC nodules (108 patients), each appearing as a high-attenuation mass on early-phase CT during hepatic arteriography and as a perfusion defect on CT during arterial portography, were evaluated. Vascular findings and contrast enhancement patterns were evaluated by contrast-enhanced harmonic gray scale imaging. Arterial pulsatile flow into each nodule was checked by power Doppler sonography. Sensitivity of each modality for depicting tumor vascularity was examined by angiography-assisted CT findings as the gold standard. The sensitivity of contrast-enhanced harmonic gray scale imaging (134/139, 96.4%) was significantly greater than that of power Doppler sonography (96/139, 69.1%) ( P<0.05). Twenty-six of twenty-seven nodules (96.3%) in the lateral segment, in which motion artifact is likely, were enhanced by contrast-enhanced harmonic gray scale imaging. Contrast-enhanced harmonic gray scale imaging is more sensitive than power Doppler sonography and is a noninvasive method that can be used as effectively as angiography-assisted CT to evaluate tumor vessels and contrast enhancement of HCC.

Detection of tumor vascularity in hepatocellular carcinoma with contrast-enhanced Dynamic Flow imaging: Comparison with contrast-enhanced power Doppler imaging.

To compare the effectiveness of contrast-enhanced Dynamic Flow imaging and contrast-enhanced power Doppler imaging using Levovist(®) as a microbubble contrast agent in evaluating intratumoral vascularity in hepatocellular carcinoma (HCC). Twenty-nine patients with 54 hepatocellular carcinoma nodules (before treatment, 31; after treatment, 23) were studied with both Dynamic Flow and power Doppler imaging with intravenous injection of Levovist(®). Tumor vascularity was categorized as 0, no blood flow signals within the tumor; 1, dotlike blood flow signals within the tumor; 2, moderate blood flow signals within the tumor; and 3, abundant blood flow signals within the tumor. Detectability of intratumoral vascularity of hepatocellular carcinoma in three groups based on tumor depth, blooming and noise artifacts on contrast-enhanced Dynamic Flow and contrast-enhanced power Doppler imaging were also compared with results obtained using dynamic CT as a the gold standard. The effectiveness of contrast-enhanced Dynamic Flow and contrast-enhanced power Doppler imaging in assessing therapeutic effect were compared at the same time. The ability of contrast-enhanced Dynamic Flow Doppler imaging to detect tumor vascularity in the superficial and intermediate hepatocellular carcinoma groups was close to that of contrast-enhanced power Doppler imaging (p>0.05). However, contrast-enhanced Dynamic Flow imaging demonstrated tumor parenchymal stain in 28 hepatocellular carcinoma nodules (61%), which was not detected by contrast-enhanced power Doppler imaging. Further, significantly fewer artifacts appeared in contrast-enhanced Dynamic Flow imaging than in contrast-enhanced power Doppler imaging (p<0.001). In assessing therapeutic response, the sensitivity of contrast-enhanced Dynamic Flow imaging was similar to that of dynamic CT. In deep areas, however, those more than 6 cm below the surface of the body, contrast-enhanced Dynamic Flow imaging was less sensitivity than contrast-enhanced power Doppler imaging (p=0.005). Contrast-enhanced Dynamic Flow imaging provides an effective approach to assessing intratumoral vascularity and therapeutic response in HCC lesions situated less than 6 cm from the surface of the body. It is superior to contrast-enhanced power Doppler imaging in its ability to detect tumor parenchymal stain and production of fewer artifacts.

Value of new contrast harmonic technique for detecting tumor vascularity in hepatocellular carcinoma: Preliminary results.

To investigate the value of a new wide-band contrast harmonic imaging method in depicting intratumoral vascularity in hepatocellular carcinoma. Twenty-two patients with 28 hepatocellular carcinoma nodules evaluated with Contrast Harmonic Echo, a new wide-band harmonic imaging method, using Levovist(®) as a contrast-enhancing agent. Intermittent imaging was carried out in the early arterial phase for 10 to 40 seconds, in the late vascular phase for 1 to 2 minutes, and in the postvascular phase for 5 to 7 minutes. Subtraction images were obtained using the multishot method during the late vascular phase. The ability of Contrast Harmonic Echo imaging to detect vascularity in hepatocellular carcinoma was compared to that of unenhanced color Doppler imaging by analzing results obtained using dynamic CT as a gold standard. Contrast harmonic Echo imaging detected intratumoral vessels, tumor parenchymal stain, and perfusion defect in the early arterial phase, the late vascular phase, and the postvascular phase, respectively. In the late vascular phase, the subtraction image clearly delineated the tumor parenchymal strain. Intratumoral vascularity was detected in 25 (89%) of the hepatocellular carcinoma nodules by Contrast Harmonic Echo, compared with 15 (54%) when color Doppler imaging was used (p<0.05). The diagnostic sensitivity, specificity, and accuracy of Contrast Harmonic Echo were 96.1%, 100% and 96.4%, respectively, corresponding to results obtained using dynamic CT. Contrast Harmonic Echo imaging is superior to unenhanced color Doppler imaging in depicting intratumoral vessels and parenchymal stain, and agrees closely with results obtained with three-phase dynamic CT.

Contrast-enhanced agent detection imaging: Early experience in hepatocellular carcinoma.

To investigate the usefulness of contrast-enhanced Agent Detection Imaging in assessing intratumoral vasculature in hepatocellular carcinoma. Fourteen hepatocellular carcinoma nodules in 11 patients were studied with contrast-enhanced Agent Detection Imaging, a wide-band color Doppler imaging method, employing, Levovist(®), a microbubble contrast agent. High acoustic power was used with contrast-enhanced Agent Detection Imaging. Intermittent transmission of Agent Detection Imaging was performed at intervals of 200, 500, and 350 milliseconds in the early arterial phase (10 to 40 seconds), late vascular phase (1 to 3 minutes) and postvascular phase (5 to 7 minutes), respectively. The results were compared with those of three-phase dynamic CT. Intratumoral blood vessels in the early arterial phase and tumor parenchymal stain in the late vascular phase were depicted in 12 (88%) of the 14 hepatocellular carcinoma nodules, while all nodules were demonstrated as perfusion defect in the postvascular phase on contrast-enhanced Agent Detection Imaging. The results of Agent Detection Imaging, that were compared with those of dynamic CT, were all 100% : diagnostic sensitivity (12/12), specificity (2/2), and accurary (14/14). Contrast-enhanced Agent Detection Imaging is a promising method for depicting intratumoral vascularity in hepatocellular carcinoma.

Assessment of image quality of contrast-enhanced power doppler imaging in hepatocellular carcinoma with the personal ultrasound imager: Comparison with the conventional machine

To evaluate the usefulness of contrast-enhanced power Doppler imaging with the personal ultrasound imager in depicting intratumoral vascularity in hepatocellular carcinoma. Contrast-enhanced power Doppler imaging was used to examine 52 hepatocellular carcinoma nodules in 29 patients, using both the personal ultrasound imager and the conventional ultrasound machine in combination with intravenous injection of Levovist(®). Results obtained using dynamic CT were used as the gold standard. The ability of the personal ultrasound imager to detect intratumoral vascularity was compared with that of the conventional ultrasound machine, and the usefulness of the personal ultrasound imager in assessing therapeutic effect after nonsurgical treatment was compared with that of dynamic CT at the same time. The personal ultrasound imager and the conventional ultrasound machine, using the fundamental power Doppler imaging mode (p=0.13) and contrast-enhanced power Doppler imaging mode (p=0.41), did not differ significantly in depicting the vascularity of the 52 hepatocellular carcinomas. The sensitivity, specificity, and accuracy of contrast-enhanced power Doppler imaging on the personal ultrasound imager were 95.5%, 87.5%, and 94.2%, respectively, in close agreement with results obtained using dynamic CT. After the 22 hepatocellular carcinomas were treated, the personal ultrasound imager provided diagnostic accuracy of 90.9% on residual tumors when compared with results obtained by dynamic CT, and results obtained using the conventional ultrasound machine were similar. The highly portable personal ultrasound imager using Levovist(®)-enhanced power Doppler imaging can clearly depict the intratumoral vascularity of hepatocellular carcinoma nodules before and after treatment, achieving results very close to those obtained using the conventional diagnostic ultrasound machine. The personal ultrasound imager is an alternative to the conventional ultrasound machine for depicting tumor vascularity.

Assessment of Hepatocellular Carcinoma Vascularity: Comparison of Contrast-enhanced Coded Harmonic Ultrasound with Harmonic Power Doppler Ultrasound

The aim of this study was to evaluate contrast-enhanced coded harmonic ultrasound (CHUS) in the depiction of the vascularity of hypervascular hepatocellular carcinomas (HCCs) by comparing it with that of contrast-enhanced harmonic power Doppler ultrasound (HPDUS). Contrast-enhanced CHUS was prospectively performed in 17 consecutively collected hypervascular HCCs (mean diameter, 3.4 cm; range, 1.8–7.8 cm) using the Coded Harmonic Angio mode of a LOGIQ 700 Expert unit and a 2 to 4 MHz curved linear-array probe. This was conducted using a microbubble contrast agent (Levovist®) and interval-delay scanning (scan interval, 20–30 s; scanning time, 2–5 s). All patients also underwent contrast-enhanced HPDUS, and the results were compared in terms of the depiction and degree of enhancement of tumor vascularity (feeding vessels, intratumoral macrovessels, intratumoral microvessels, and tumor staining), and the presence of artifacts. There was no significant difference between CHUS and HPDUS in depiction of tumor vascularity in terms of feeding vessels, intratumoral macrovessels and intratumoral microvessels. CHUS, however, was superior to HPDUS in terms of tumor staining ( p = 0.008). The degree of tumor vascularity enhancement was superior with CHUS in depicting tumor staining ( p = 0.001), but HPDUS was better in depicting intratumoral macrovessels ( p = 0.039). CHUS was artifact-free, while several artifacts were seen in all HCCs examined with HPDUS. Our results suggest that CHUS is capable of depicting tumor vascularity of hypervascular HCCs and is superior to HPDUS. Contrast-enhanced CHUS may be useful, therefore, in evaluating tumor vascularity of HCCs.

Diagnosis of hepatocellular carcinoma using digital subtraction imaging with the contrast agent, levovist: Comparison with helical CT, digital subtraction angiography, and US angiography

Digital subtraction imaging was compared to helical CT, DSA, and US angiography to assess its usefulness in the evaluation of vascularity in hepatocellular carcinoma (HCC). Digital subtraction imaging using Levovist as the contrast agent was performed in 41 patients with 43 nodules (22 men and 19 women, aged 50 to 83 years; mean age, 65 years; mean maximum tumor diameter, 27.8+/-17.1 mm). Digital subtraction imaging showed hypervascular enhancement in 39 of the 43 nodules (91%). Helical CT showed areas of high attenuation in 40 of the 43 nodules (93%), while DSA and US angiography showed positive enhancement in 38 and 43 of the 43 nodules (88% and 100%), respectively. Digital subtraction imaging is useful for evaluating vascularity in HCC when the tumor can be visualized with non-enhanced US angiography.

Intravenous contrast-enhanced Doppler sonography and intra-arterial carbon dioxide-enhanced sonography in the assessment of hepatocellular carcinoma vascularity before and after treatment

To compare i.v. contrast-enhanced sonography (CEUS), power Doppler sonography (PDUS) and i.a. carbon dioxide-enhanced sonography (CO2US) in assessing hepatocellular carcinoma (HCC) vascularities before and after treatment. Differences between PDUS and CEUS with the aid of CO2US were also observed. In all, 43 patients with 67 histologically proved HCCs were examined with PDUS, CEUS, and CO2US. Among these tumors, 36 were HCCs before treatment and 31 were HCCs treated by transcatheter arterial chemoembolization or percutaneous ethanol injection or a combination of these two treatments. CO2US was used as the gold standard when comparing the PDUS and CEUS. Of the 36 untreated HCC tumors, 20 (55.6%) were hypervascular compared with the liver parenchyma at PDUS, 28 (77.8%) at CEUS, 31 (86.1%) at the early phase of CO2US and 32 (88.9%) at the late phase of CO2US. Of the 31 post-treatment HCCs, 11 (35.5%) showed hypervascularity at PDUS, 25 (80.6%) at CEUS, 25 (80.6%) at the early phase of CO2US and 26 (83.9%) at the late phase of CO2US. CO2US was superior to CEUS and CEUS was superior to PDUS for the detection of tumor vascularity in both untreated and treated HCCs. The duration of enhancement at CEUS was shorter than at CO2US. The ability of CO2US to detect additional small tumors was not possible with PDUS and CEUS.

Hepatocellular carcinoma: contrast enhancement with Levovist.

To present the sonographic appearance of hepatocellular carcinoma imaged with the intravenous contrast agent Levovist. We reviewed our experience using Levovist (Schering AG, Berlin, Germany) for the sonographic diagnosis of hepatocellular carcinoma. Contrast-enhanced sonography with Levovist facilitated detailed evaluation of tumor vascularity in hepatocellular carcinoma. Contrast-enhanced sonography with Levovist enhances the role of sonography in the diagnosis of hepatocellular carcinoma. It provides detailed information about tumor vascularity and the contrast enhancement pattern.

Contrast-enhanced subtraction harmonic sonography for evaluating treatment response in patients with hepatocellular carcinoma.

Our objective was to assess the usefulness of contrast-enhanced subtraction harmonic sonography in evaluating the treatment response of patients with hepatocellular carcinoma. Thirty-two hepatocellular carcinoma lesions in 26 patients (age range, 44-85 years; mean age, 66 years) were examined with Levovist-enhanced intermittent harmonic imaging before and after therapy. A Toshiba Powervision 8000 was used. A subtraction image was obtained by digitally subtracting the last-frame harmonic image from the first-frame image when multishot mode was preset. Results of contrast-enhanced CT were compared with the results of subtraction harmonic imaging. Before therapy, an enhancement pattern of tumor vascularity was seen for 93.8% (30/32) of hepatocellular carcinoma nodules on subtraction harmonic imaging. After therapy, subtraction harmonic imaging showed 46.7% (14/30) enhancement (incomplete tumor necrosis) and 53.3% (16/30) no enhancement (complete tumor necrosis). When dynamic CT was the gold standard, the sensitivity, specificity, and accuracy of subtraction harmonic imaging were 93.3%, 100%, and 96.7%, respectively. Intratumoral flow signals in hepatocellular carcinoma after therapy on harmonic imaging were used as a guide to target additional percutaneous therapy. Digital subtraction contrast-enhanced harmonic imaging can depict tumor vascularity in hepatocellular carcinoma after therapy sensitively and accurately. Because it is easy to perform and provides real-time needle insertion guidance, it may be preferable to perform after localized therapy to monitor treatment response, which will reduce unnecessary CT scanning.