Enhancement pattern of hepatocellular carcinoma: comparison of real-time contrast-enhanced ultrasound and contrast-enhanced computed tomography

We compared the enhancement pattern of 98 hepatocellular carcinoma nodules in 92 patients on contrast-enhanced ultrasound (CEUS) and contrast-enhanced computed tomography (CECT). Contrast-enhanced ultrasound was performed with SonoVue and a low mechanical index method. In arterial phase, 98 nodules were hyperenhancing on CEUS and 94 on CECT. In portal phase, 82 nodules were hypoenhancing on CEUS and 83 on CECT. Peripheral thin-rim-like enhancement was exhibited in 30 nodules on CEUS and 31 on CECT. Intratumoral vessels were visualized in 94 nodules on CEUS and 36 on CECT.     

肝细胞肝癌的超声造影参数成像分析研究

目的探讨超声造影参数成像分析在肝细胞肝癌(HCC)诊断中的应用价值。方法分析68例HCC的超声造影资料,应用SonoLiverR CAP定量分析软件,以HCC与周围肝实质的增强水平差值为参数进行动态血管模型(dy-namic vascular pattern,DVP)重建,分析结果以DVP彩色编码图、DVP曲线图及定量参数显示,并进行分型及统计学分析。结果 DVP彩色编码图:消退型,未消退型分别占88.24%(60/68)和11.76%(8/68);DVP曲线图:消退型,未消退型分别占83.82%(57/68)和16.18%(11/68)。定量参数显示HCC与周围肝实质的峰值强度、上升时间、达峰时间和平均渡越时间的差异均具有统计学意义(P<0.05)。结论超声造影参数成像可直观、量化的显示病灶变化,为HCC诊断提供更为准确的定量信息。     

Management of hepatocellular carcinoma: The role of contrast-enhanced Tultrasound简

Hepatocellular carcinoma (HCC) is the sixth most common neoplasm and the third cause of cancer death worldwide. Contrast enhanced ultrasound (CEUS) has been applied for more than ten years and plays increasingly important roles in the management of HCC. On the basis of the Guideline and Good Clinical Practice Recommendations for CEUS in the liver-update 2012 and related literature about the management of HCC, we summarize the main roles and applications of CEUS in the management of HCC, including HCC surveillance, diagnosis, CEUS-guided treatment, treatment response evaluation and follow-up. The diagnostic algorithm for HCC is also suggested. Meanwhile, the comparisons between CEUS and contrast enhanced computed tomography/magnetic resonance imaging (CECT/CEMRI) in these areas are made. Although CEUS is subject to the same limitation as ordinary US and is inferior to CECT/CEMRI in some aspects, CEUS has proved to be of great value in the management of HCC with inherent advantages, such as sufficient high safety profile making it suitable for patients with renal failure or allergic to iodine, absence of radiation, easy reproducibility and high temporal resolution. The tremendous application of CEUS to the diagnosis and treatment of HCC provides more opportunities for patients with HCC diagnosed at different stages.     

Intrahepatic cholangiocarcinoma and hepatocellular carcinoma: differential diagnosis with contrast-enhanced ultrasound

Objective

We assessed the usefulness of contrast-enhanced ultrasound (CEUS) in the differentiation of intrahepatic cholangiocarcinoma (ICC) and hepatocellular carcinoma (HCC).

Methods

The CEUS enhancement patterns of 50 ICCs were retrospectively analysed and compared with 50 HCCs. Two readers independently reviewed the baseline ultrasound (BUS) and CEUS images and the diagnostic performances were evaluated by receiver operating characteristic (ROC) analysis. Time–intensity curves (TIC) were plotted for quantification analysis.

Results

In the arterial phase, peripheral rim-like hyperenhancement, heterogeneous hyperenhancement, homogeneous hyperenhancement and heterogeneous hypoenhancement were found in 25, 10, 3 and 12 of the ICCs versus 2, 29, 19 and 0 of the HCCs (P?<?0.001), respectively. The diagnostic performance of both readers in terms of the area under the ROC curve (0.745 vs. 0.933 for reader 1, and 0.803 vs. 0.911 for reader 2), sensitivity (28% vs. 90%, and 44% vs. 82%) and accuracy (64% vs. 90%, and 71% vs. 90%) improved significantly after CEUS (all P?<?0.05). The interobserver agreement increased from κ?=?0.575 at BUS to κ?=?0.720 after CEUS. TICs demonstrated that the intensities of the peripheral and central portions of the ICCs were lower than those of HCCs (both P?<?0.05).

Conclusion

CEUS improves the diagnostic performance significantly in the differentiation between ICC and HCC.     

Lipiodol retention and massive necrosis after lipiodol-chemoembolization of hepatocellular carcinoma: Correlation between computed tomography and histopathology

This retrospective study examined the computed tomography (CT) criteria for judging the effectiveness of transcatheter arterial Lipiodolchemoembolization (Lp-chemo-TAE) in 35 cases with hepatocellular carcinoma (HCC). Massive necrosis, defined as involving 97% or more of the HCC nodule, was observed in 15 cases after Lp-chemo-TAE, whereas nonmassive necrosis, defined as involving ≤96% of the HCC nodule, was observed in the remaining 20 cases. In 12 of 15 cases (80%) with massive necrosis, uniform dense retention of Lipiodol (Lp) was observed throughout the HCC nodule on CT images 3–4 weeks after Lp-chemo-TAE as opposed to only one (5%) of 20 cases with nonmassive necrosis (p<0.01). Eight of nine cases (89%) with massive necrosis had tumor attentuation values of 365 Hounsfield units (HU) or greater on CT images 3–4 weeks after embolization, as opposed to only four (27%) of 15 cases with nonmassive necrosis (p<0.01). We conclude that the effectiveness of the Lp-chemo-TAE can be judged on CT from the degree and duration of Lp retention in the HCC nodule and the measurement of the attenuation value of the HCC nodule.     

原发性肝细胞癌锰福地匹三钠增强MRI强化指数与其分化程度的相关性探讨

目的　探讨原发性肝细胞癌 (HCC)的锰福地匹三钠 (MnDPDP)增强MRI强化指数与其分化程度的相关性。方法　将 4 3个由MRI检出并经手术切除治疗的HCC病灶强化指数 ,与其病理分化程度分级进行对照。于轴位正中层面图像上将 4 3个HCC病灶分为均匀强化和不均匀强化 ;将后者分成高、等、低 3个区域 ,并分别计 3、2、1分 ;按不同信号强度区所占该层面的百分比计算不同区域的分值 ,将不同区域的分值相加即得“病灶强化指数” ,最后将病灶强化指数与其病理分级相对照。病理检查取材部位与不同强度信号区相对应 ,并包括瘤 肝交界处。结果　对 4 3个HCC的 113处进行了Edmondson和Steiner分级 :Ⅰ级 13处 ,Ⅰ～Ⅱ级 7处 ,Ⅱ级 5 0处 ,Ⅱ～Ⅲ级 2 2处 ,Ⅲ级 19处 ,Ⅲ～Ⅳ级 1处 ,Ⅳ级 1处。高信号、等信号和低信号分别为 81、17和 15处。增强后HCC高、等、低信号区与其分化程度之间具有显著相关性 (χ2 =2 6 .75 ,P <0 .0 0 5 )。病灶强化指数与其分化程度之间具有显著相关性 (χ2 =7.94 ,P <0 .0 0 5 )。结论　HCCMnDPDP增强MRI强化指数与其分化程度具有显著相关性。     

Imaging features of hepatic angiomyolipomas on real-time contrast-enhanced ultrasound

The aim of this study was to evaluate the imaging features of hepatic angiomyolipoma (AML) on contrast-enhanced ultrasound (CEUS). The imaging features of 12 pathologically proven hepatic AML lesions in 10 patients who had undergone baseline ultrasound (BUS) and CEUS examinations were evaluated retrospectively. The enhancement extent, pattern and dynamic change, along with the enhancement process, on CEUS were analysed. The diagnostic results of BUS and CEUS before pathological examination were also recorded. The results showed that 75% (9/12) of the AML lesions exhibited mixed echogenicity on BUS and most showed remarkable hyperechogenicity in combination with a hypoechoic or anechoic portion. Arterial flow signals were detected in 75% (9/12) of the lesions on colour Doppler imaging. On CEUS, 66.7% (n = 8) of the 12 lesions exhibited hyperenhancement in the arterial phase, slight hyperenhancement (n = 2) or isoenhancement (n = 6) in the portal phase, and slight hyperenhancement (n = 1) or isoenhancement (n = 7) in the late phase. Three (25%) lesions exhibited hyperenhancement in the arterial phase and hypoenhancement in both portal and late phases. One (8.3%) lesion exhibited hypoenhancement throughout the CEUS process. Before pathological examination with BUS, only 3 (25%) lesions were correctly diagnosed as hepatic AML. Conversely, on CEUS, correct diagnoses were made for 66.8% (8/12) of hepatic AMLs. Therefore, arterial hyperenhancement and subsequent sustained enhancement on CEUS were found in the majority of hepatic AMLs. The combination of BUS and CEUS leads to the correct diagnosis in the majority of hepatic AMLs, and is higher than the success rate achieved by BUS alone.Hepatic angiomyolipoma (AML) is generally considered a rare benign mesenchymal tumour of the liver [1]. With the increasing clinical application of imaging, more and more hepatic AMLs are being detected [2, 3]. Baseline ultrasound (BUS) is the first-line imaging modality for liver use owing to its relatively low cost, non-invasiveness, easy manipulation and ready availability; however, its ability to characterise focal liver lesions (FLLs) cannot meet the requirement in the clinical setting [4]. The advent of the second-generation ultrasound contrast agents and contrast-specific ultrasound techniques allows depiction of the micro- and macro-circulation of FLLs, which has facilitated a great improvement in the characterisation of FLLs [5, 6]. However, until now, few reports in the literature have described the use of contrast-enhanced ultrasound (CEUS) in hepatic AML [7–11]. Herein we analyse retrospectively the imaging features of 12 hepatic AMLs on CEUS; the diagnostic results of BUS and CEUS before pathological examination are also recorded.     

Evaluation of hepatocellular carcinoma using SonoVue,a second generation ultrasound contrast agent: correlation with cellular differentiation

The appearance of hepatocellular carcinoma (HCC) with contrast-enhanced ultrasound (CEUS) in the vascular phase is described and evaluated as to whether the enhancement pattern correlates with the degree of cellular differentiation. One hundred four HCCs were prospectively evaluated with CEUS using coherent-contrast imaging (CCI) and SonoVue with a low mechanical index (<0.2). The enhancement of HCCs in the vascular phase was analyzed according to the degree of pathological differentiation obtained by fine-needle biopsy. In the arterial phase, all HCCs except for four well differentiated ones (96.2%) showed enhancement (P<0.05). Histological differentiation of hypoechoic lesions in the early portal phase (7 HCCs; 16%) significantly differed from hyperechoic (1 HCC; 1%) or isoechoic lesions (87 HCCs; 83.6%) (P<0.05), with a significant probability of a worse differentiation in hypoechoic lesions. Histological differentiation of isoechoic lesions in the late phase (30 HCCs; 28.8%) significantly differed from hypoechoic lesions (74 HCCs; 71.2%) (P<0.05), with a significant probability of a better differentiation in isoechoic lesions. CEUS using CCI and SonoVue revealed enhancement in the arterial phase in >95% of HCCs, with a few well-differentiated cases not being diagnosed due to the absence of enhancement. Echogenicity in the portal and late phases correlated with cellular differentiation.     

Clinical utility of contrast-enhanced three-dimensional ultrasound imaging with Sonazoid: Findings on hepatocellular carcinoma lesions

ObjectivesWe investigated clinical utility of contrast-enhanced three-dimensional ultrasound (CE 3D US) imaging with contrast medium Sonazoid for demonstrating characteristic enhancement of hepatocellular carcinoma (HCC).MethodsAmong 115 focal liver tumors undergoing CE 3D US imaging, 70 HCCs confirmed with contrast-enhanced multi-detector computed tomography, contrast-enhanced magnetic resonance imaging or histopathologic examination were retrospectively analyzed. CE 3D US imaging was performed using Autosweep 3D scan functionality in the early, middle and late phase, after bolus injection of 0.2 ml Sonazoid. The CE 3D tomographic images reconstructed in parallel slices and sonographic angiogram images were independently reviewed by two reviewers. Kappa values were used to assess inter-reviewers’ agreement.ResultsTUI images showed most of HCCs were detected with intratumoral vessels and early tumor enhancement in the early phase, expressed homogenous or heterogeneous tumor enhancement in the middle phase, and became hypoechoic or isoechoic in the late phase. The kappa values in the early, middle and late phase for inter-reviewer agreements regarding the characteristic enhancement of tumors were 0.817, 0.774, and 0.785. In addition, TUI images demonstrated satellite foci and tortuous tumor vessels in three orthogonal planes. Sonographic angiogram reconstructed by different rendering modes showed the vessels and tumor stain in spatial view. The spatial configuration of anatomic structures was revealed on basis of both TUI and sonographic angiogram images.ConclusionCE 3D US imaging, with spatial visualization, is clinically useful to exhibit the characteristic enhancement of HCC tumors objectively.     

Clinical utility of contrast-enhanced three-dimensional ultrasound imaging with Sonazoid: findings on hepatocellular carcinoma lesions

Objectives

We investigated clinical utility of contrast-enhanced three-dimensional ultrasound (CE 3D US) imaging with contrast medium Sonazoid for demonstrating characteristic enhancement of hepatocellular carcinoma (HCC).

Methods

Among 115 focal liver tumors undergoing CE 3D US imaging, 70 HCCs confirmed with contrast-enhanced multi-detector computed tomography, contrast-enhanced magnetic resonance imaging or histopathologic examination were retrospectively analyzed. CE 3D US imaging was performed using Autosweep 3D scan functionality in the early, middle and late phase, after bolus injection of 0.2 ml Sonazoid. The CE 3D tomographic images reconstructed in parallel slices and sonographic angiogram images were independently reviewed by two reviewers. Kappa values were used to assess inter-reviewers’ agreement.

Results

TUI images showed most of HCCs were detected with intratumoral vessels and early tumor enhancement in the early phase, expressed homogenous or heterogeneous tumor enhancement in the middle phase, and became hypoechoic or isoechoic in the late phase. The kappa values in the early, middle and late phase for inter-reviewer agreements regarding the characteristic enhancement of tumors were 0.817, 0.774, and 0.785. In addition, TUI images demonstrated satellite foci and tortuous tumor vessels in three orthogonal planes. Sonographic angiogram reconstructed by different rendering modes showed the vessels and tumor stain in spatial view. The spatial configuration of anatomic structures was revealed on basis of both TUI and sonographic angiogram images.

Conclusion

CE 3D US imaging, with spatial visualization, is clinically useful to exhibit the characteristic enhancement of HCC tumors objectively.     

Histological differentiation grade and microvascular invasion of hepatocellular carcinoma predicted by dynamic contrast-enhanced MRI

Purpose:

To explore the potential use of magnetic resonance imaging (MRI) in predicting the outcome for patients with hepatocellular carcinoma (HCC), imaging characteristics were correlated with pathological findings and clinical outcome.

Materials and Methods:

With permission from the Ethical Board, clinical data and tissues of resected HCC patients were collected, including the preoperative MRI. The role of MRI characteristics on recurrence and survival were evaluated with univariate and multivariate analyses.

Results:

Between January 2000 and December 2008, 87 patients with 104 HCCs were operated on. Microvascular invasion was present in 55 lesions (53%). HCC was characterized as well differentiated in 15 lesions (14%), as moderate in 50 lesions (48%), and as poorly differentiated in 34 lesions (33%). Due to preoperative treatment in five lesions (5%) no vital tumor was left. In 85 lesions (88%) washout of contrast was noted. Of the 87 patients, 28 (32%) with 37 lesions developed HCC recurrence; these patients had microvascular invasion significantly more often and a moderate or poorly differentiated tumor (P < 0.001 and P = 0.025, respectively). MRI more often showed washout when HCC was moderately or poorly differentiated (P < 0.001) or microvascular invasion was present (P = 0.032).

Conclusion:

Differentiation grade and microvascular invasion are significantly associated with the presence of washout demonstrated on dynamic contrast‐enhanced MRI. J. Magn. Reson. Imaging 2012;36:641–647. © 2012 Wiley Periodicals, Inc.     

初探超声造影基于LI-RADS分类标准诊断肝细胞癌的可行性

目的：探讨基于肝脏影像报告和数据管理系统（LI-RADS）的超声造影检查诊断肝细胞癌（HCC）的可行性。方法：回顾性分析108例有肝癌高风险的单发肝脏病变患者的超声造影资料,并基于LI-RADS分类标准对肝脏病变进行分析评估,并与病理或临床诊断结果相对照。结果：108个病灶中LI-RADS 1～5类病灶共106个：1类和2类病灶19个,临床客观诊断结果均为良性（阴性预测值为100％）;3类病灶3个;22个4类病灶中17个为 HCC（阳性预测值为77．3％）;62个5类病灶中有54个为 HCC（阳性预测值为87．1％）。受试者工作特征（ROC）曲线下面积为0．83（P＜0．001）。若将LI-RADS 3～5类病灶归为阳性,基于LI-RADS的超声造影检查对HCC的诊断符合率为83．9％（92／106）,敏感度为100％（73／73）,特异度为57．6％（19／33）,阳性预测值为83．9％（73／87）,阴性预测值为100％（19／19）;若将 LI-RADS 3类病灶排除、1～2类病灶归为阴性、4～5类病灶归为阳性,则诊断符合率为87．4％（90／103）,敏感度为100％（71／71）,特异度为59．4％（19／32）,阳性预测值为84．5％（71／84）,阴性预测值为100％（19／19）。结论：超声造影检查中应用LI-RADS分类标准诊断 HCC具有一定的可行性。     

子宫肌瘤与子宫腺肌症超声造影强化形式的临床应用

目的：探讨超声造影强化形式在子宫肌瘤与子宫腺肌症鉴别诊断中的临床应用。方法：回顾性分析经手术或病理证实的子宫肌瘤和子宫腺肌症患者70例的超声造影表现,记录造影时病灶的充填方式、与肌层的成像顺序及增强程度等。结果：子宫肌瘤患者50例（72个病灶）,子宫腺肌症患者20例。3 cm以上肌瘤56个,均表现为假包膜先充填,呈周边环状增强,然后肌瘤内部增强,消退时肿瘤中央先消退,包膜增强持续时间较长,与周边正常肌层组织充盈方式显著不同。3 cm以下肌瘤16个,呈环绕型增强8个,树枝型增强2个（混合型增强6个）。20例子宫腺肌症均表现为与子宫肌层同步增强,同步减退,且增强程度低于子宫肌层,呈不均匀增强,可见虫蚀样充盈缺损区。结论：超声造影强化形式对子宫肌瘤和子宫腺肌症的鉴别诊断有重要价值。     

Parametric response mapping of contrast-enhanced biphasic CT for evaluating tumour viability of hepatocellular carcinoma after TACE

Objectives

To determine the feasibility and role of parametric response mapping (PRM) for quantitative assessment of regional contrast-enhancement patterns in hepatocellular carcinoma (HCC).

Methods

Biphasic CT of 19 patients receiving repetitive conventional transarterial chemoembolisation (cTACE) for intermediate stage HCC were retrospectively analysed at baseline and follow-up at 3, 6, and 9 months. Voxel-based registration of arterial and porto-venous phases, with segmentation of the largest target lesion was performed. Frequency distribution plots of density-pairs of segmented voxels were generated. To differentiate necrotic, hypervascular and non-hypervascular tumour, and lipiodol/calcification, thresholds of 30, 100, and 300 HU were applied. Changes in density frequency plots over time were analysed and compared to response and assessment criteria (WHO, RECIST, EASL, mRECIST) and survival.

Results

PRM was feasible in all cases. Tumour volumes and hypervascular/non-hypervascular volume ratio showed significant longitudinal decrease (p?<?0.05). Hypervascular volume at baseline was inversely correlated to survival (R?=?-0.57, p?=?0.005). The only predictive parameter following cTACE to show significant survival difference was the change of the viable/non-viable ratio (p?=?0.044), whereas common response assessment criteria showed no significant difference in survival.

Conclusions

PRM allows a quantitative and more precise assessment of regional tumour vascularisation patterns and may be helpful for TACE treatment planning and response assessment.

Key Points

? PRM allows more precise assessment of tumour vascularisation compared to conventional evaluation ? PRM is beneficial for cTACE treatment planning and response assessment ? PRM allows a quantitative assessment of regional contrast enhancement patterns

     

Assessment of hepatocellular carcinoma by contrast-enhanced ultrasound with perfluorobutane microbubbles: comparison with dynamic CT

Objective

The aim of this study was to evaluate tumour vascularity and Kupffer cell imaging in hepatocellular carcinoma (HCC) using contrast-enhanced ultrasonography (CEUS) with Sonazoid (perfluorobutane) and to compare performance with dynamic CT.

Methods

We studied 118 nodules in 88 patients with HCC. HCC was diagnosed as a hyperenhancement lesion in the arterial phase with washout in the portal phase on dynamic CT or by percutaneous biopsy. We observed tumour vascularity at the early vascular phase (10–30 s after contrast injection) and Kupffer imaging at the post-vascular phase (after 10 min).

Results

Detection of vascularity at the early vascular phase was 88% in nodules that were found to be hypervascular on dynamic CT and 28% in hypo-/isovascular nodules; the detection of local recurrence nodules was 92%. The detection of vascularity was significantly lower in nodules >9 cm deep than in those ≤9 cm deep, but was not affected by tumour size. The detection of tumours at the post-vascular phase on CEUS was 83% in nodules with low density in the portal phase on dynamic CT and 82% in nodules with isodensity. The rate did not depend on the severity of underlying liver disease; rates decreased in nodules deeper than 9 cm, those smaller than 2 cm in diameter and in iso-enhancing nodules at the early vascular phase of CEUS.

Conclusion

CEUS with Sonazoid is a useful tool for assessing the vascularity of HCC and is equal to that of dynamic CT; however, the detectability of HCC vascularity is affected by location.The development of imaging modalities has facilitated the detection and accurate diagnosis of hepatocellular carcinoma (HCC). Assessment of tumour vascularity and for the presence of Kupffer cells are important in differential diagnosis, the choice of treatment and for assessment of the therapeutic response. HCC tumour vascularity has been evaluated extensively using various imaging modalities, including colour or power Doppler ultrasonography [1,2], angiography, dynamic CT [3], CT during angiography [4,5] and MRI [3]. Dynamic helical CT is minimally invasive and provides information regarding arterial or portal supplies by scanning at different time intervals following an injection of contrast agent. Therefore, dynamic CT is the standard modality used in clinical assessment of tumour vascularity. Assessment of Kupffer cells is possible using superparamagnetic iron oxide (SPIO)-enhanced MRI [6,7]. The presence of Kupffer cells indicates normal or benign liver tissue, whereas the absence of Kupffer cells indicates non-liver tissue such as malignant neoplasms. Thus, evaluation of the presence of Kupffer cells is useful in the differential diagnosis of focal liver lesions.Microbubble contrast agents are available for clinical use with ultrasound. Levovist (Schering AG, Berlin, Germany) is a first-generation contrast agent widely used to characterise focal liver lesions [8-12]. The advent of Sonazoid, a second-generation contrast agent (perfluorobutane; Diichi Sankyo, Tokyo, Japan), enables low mechanical index continuous real-time imaging and Kupffer imaging [13-15]. Therefore, contrast-enhanced ultrasound (CEUS) using Sonazoid could potentially offer high-quality, detailed vascular information and clearer Kupffer imaging. The aim of the present study was to compare CEUS using Sonazoid with dynamic CT in the assessment and characterisation of HCC.     

Therapeutic effect of transcatheter arterial chemoembolization on hepatocellular carcinoma: evaluation with contrast-enhanced harmonic power Doppler ultrasound

The aim of this study was to investigate the usefulness of contrast-enhanced harmonic power Doppler ultrasound (US) for the detection of residual viable hepatocellular carcinoma (HCC) after treatment with transcatheter arterial chemoembolization (TACE). Forty-seven patients with 68 HCC lesions 1.8–9.5 cm in diameter (mean ± SD 4.3 ± 1.7 cm) underwent contrast-enhanced power Doppler US, in the harmonic mode, before and after treatment with TACE. Unenhanced spiral CT and contrast-enhanced dynamic MR imaging were also performed to help establish the outcome of therapy. Before treatment, intratumoral blood flow signals were detected at contrast-enhanced harmonic power Doppler US in 65 (95 %) of 68 lesions. After TACE, flow signals were no longer detectable in 22 of these 65 lesions, which showed complete response at spiral CT and dynamic MR imaging. In 38 (88 %) of the 43 lesions with partial response, intratumoral flow signals were still identified at contrast-enhanced harmonic power Doppler US. Twenty-eight of these 38 lesions underwent additional treatment with percutaneous ethanol injection (PEI) using contrast-enhanced harmonic power Doppler US guidance. Complete response was seen after PEI in 23 of 28 lesions. Contrast-enhanced harmonic power Doppler US proved useful for assessing the therapeutic effect of TACE on HCC and for guiding additional treatment with PEI in cases of partial response. Received: 25 January 2000; Revised: 21 April 2000; Accepted: 25 April 2000     

Histopathologic diversity of gastric cancers: Relationship between enhancement pattern on dynamic contrast-enhanced CT and histological type

PurposeTo evaluate the diagnostic value of contrast-enhanced computed tomography gastrography (CE-CTG) to predict the histological type of gastric cancer.Materials and methodsWe analyzed 47 consecutive patients with resectable advanced gastric cancer preoperatively evaluated by multiphasic dynamic contrast-enhanced CT. Two radiologists independently reviewed the CT images and they determined the peak enhancement phase, and then measured the CT attenuation value of the gastric lesion for each phase. The histological types of gastric cancers were assigned to three groups as differentiated-type, undifferentiated-type, and mixed-type. We compared the peak enhancement phase of the three types and compared the CT attenuation values in each phase.ResultsThe peak enhancement was significantly different between the three types of gastric cancers for both readers (reader 1, p = 0.001; reader 2, p = 0.009); most of the undifferentiated types had peak enhancement in the delayed phase. The CT attenuation values of undifferentiated type were significantly higher than those of differentiated or mixed type in the delayed phase according to both readers (reader 1, p = 0.002; reader 2, p = 0.004).ConclusionCE-CTG could provide helpful information in diagnosing the histological type of gastric cancers preoperatively.