Hepatocellular carcinoma with ring calcification: report of two cases

Two cases of hepatocellular carcinoma (HCC) with ring calcification are reported together with their CT findings. HCC in both cases showed little early enhancement followed by delayed enhancement on dynamic CT. The pathologic specimen in one case showed HCC with fairly abundant fibrosis, and calcification was noted underneath the thick fibrous capsule, which might explain the enhancement pattern on CT.     

肝细胞癌瘤内出血1例及文献复习

目的根据肝细胞癌瘤内出血的CT表现,复习肝脏肿块自发出血的鉴别诊断。方法分析1例低分化肝细胞癌合并瘤内出血病人的CT表现并检索和复习肝脏肿块内自发出血的影像诊断文献报道。结果腹部B超检查肝右叶可见中强回声区,边界清晰,其内部回声不均并见少量液化区。CT平扫可见肝实质混杂密度肿块,肿块内见片状高密度区和低密度区,肿块边缘见不规则软组织成分;增强检查显示肿块边缘软组织密度于肝动脉期强化,门静脉期和平衡期相对于肝实质强化程度降低,高密度和低密度区无强化。手术病理学检查为低分化肝细胞癌合并瘤内出血。结论肝脏肿块内自发出血少见,全面观察肿块,识别肿块内的软组织成分是鉴别诊断关键。     

肝细胞癌肝实质一过性异常强化病理研究

目的:探讨肝细胞癌肝实质一过性异常强化的影像学特征及病理改变。方法:选择肝脏动态增强CT扫描肝细胞癌合并肝实质一过性异常强化征象病例21例,以肝实质一过性异常强化区域为研究对象,并通过手术切除和CT引导下穿刺活检的方法进行病理检查。结果:肝实质一过性异常强化征象表现为肿块以外肝实质动脉期显著强化,门静脉期或延迟期呈等密度,楔形或三角形13例,不规则形9例,叶段形6例。肝实质一过性异常强化征象与癌细胞向周围扩散和肝内转移无相关性。结论:明确肝细胞癌肝实质一过性异常强化的形成机制及病理基础,有助于肿瘤的分期和制定治疗方案。     

电子束CT流动检查评价原发性肝癌

目的 应用电子束ＣＴ（ＥＢＣＴ）流动扫描研究原发性肝癌的时间－密度曲线特点与因供和病理的对应关系,以期提高诊断的特异性和准确性。方法 ３１例肝脏肿块者均行ＥＢＣＴ流动扫描。静脉注射对比剂８０￣１００ｍｌ,速度为６￣８ｍｌ／ｓ,病灶区扫描６层,每层扫描１３次,需时１２０秒。画出时间－密度曲线及测量各参数值。结果 ３１例肝癌均表现为不同程度的增强。小于５ｃｍ的肝癌与大于５ｃｍ肝癌和弥漫型肝癌其增强类型     

Imaging of cholangiolocellular carcinoma of the liver

Aim

Cholangiolocellular carcinoma (CoCC) is currently considered to originate from hepatic progenitor cells. The purpose of this study was to evaluate the imaging features of cholangiolocellular carcinoma of the liver.

Materials and methods

Five cases of surgically resected cases of CoCC from 4 institutions were retrospectively evaluated. All of the five patients underwent contrast-enhanced dynamic CT. MRI and angio-CT including CT during arterioportography (CTAP) and CT during hepatic arteriography were performed in 3 and 2 patients, respectively. Histological evaluation was also performed and was correlated with radiographic findings.

Results

On dynamic CT or MRI, the lesions presented hypervascular tumors with delayed washout in 2 cases and in the other 3 cases, the lesions showed peripheral enhancement with concentric delayed filling. On CTAP, the continued existence of portal veins or tiny spots of portal flow was identified in the tumors. Fibrous capsule or tumor necrosis was not observed.

Conclusion

CoCC tumors have the dual imaging characteristics of hepatocellular carcinoma and cholangiocarcinoma. The absence of a fibrous capsule, the absence of tumor necrosis, peripheral location within the liver, and the presence of portal venous penetration within the tumor also appear to be characteristic features.     

螺旋CT多时相扫描鉴别诊断肝细胞癌和血管瘤

目的:探讨螺旋CT多时相扫描对肝细胞癌和血管瘤的鉴别诊断。材料和方法:对37例患者(肝癌16例,血管瘤21例)行螺旋CT平扫和增强扫描,分析其表现。结果:37例平扫均发现低密度灶。肝细胞癌在动脉期75%有显著增强,呈高密度,在门静脉期和延迟期则呈低密度;血管瘤54%动脉期有典型增强表现,门静脉期100%有增强,24%全部填充,延迟期91%为高密度或等密度。结论:肝细胞癌和血管瘤在螺旋CT多时相增强扫描中,各有其典型的CT表现,两者鉴别的关键是门静脉期。     

Delayed enhancement of fibrotic areas in hepatic masses: CT-pathologic correlation.

We report a histological analysis of the areas of high density in the postequilibrium and delayed phase CT in 43 focal hepatic lesions. The cases consisted of 16 cholangiocellular carcinomas, 9 hepatocellular carcinomas (including a sclerosing type of hepatocellular carcinoma and a combined hepatocellular-cholangiocellular carcinoma), 13 metastases, 2 granulomas, an inflammatory pseudotumor, a malignant lymphoma, and an epithelioid hemangioendothelioma. Computed tomography was performed after hepatic angiography using 40-50 g iodine and arteriographic CT using 35 g iodine. The areas of delayed enhancement corresponded histologically to fibrotic tissues, from inflammatory change to extensive fibrosis.     

肝胆特异性磁共振对比剂Gd-EOB-DTPA在肝脏局灶性病变诊断中的应用研究

目的:探讨Gd-EOB-DTPA MRI增强扫描时肝局灶性病变的表现及此新型对比剂的诊断效能,提高对肝脏局灶性病变的诊断准确性。方法:已知或怀疑为肝脏局灶性病变的34例患者共90个病灶,病灶性质依次为肝囊肿20个、肝细胞肝癌16个、胆管细胞癌1个、肝脏转移性肿瘤37个、肝血管瘤9个、退变结节1个、肝脏局灶性结节增生1个、肝细胞腺瘤1个、肝脏炎性病变3个及肝脏淋巴上皮瘤样癌1个。所有患者依次行MRI平扫(抑脂TSE T2WI、抑脂3DVIBE、2DGRE T1WI)、Gd-EOB-DTPA三期(动脉期、门脉期和平衡期)增强扫描(抑脂3DVIBE)及延迟20min肝实质期扫描(抑脂2DGRE T1WI、抑脂TSE T2WI、抑脂3DVIBE)。测量并分析Gd-EOB-DTPA增强前后肝脏和病灶信号变化、病灶-肝脏对比噪声比绝对值(|CNR|)变化情况,并观察病灶Gd-EOB-DTPA增强扫描表现和特征。结果:Gd-EOB-DT-PA增强后各期肝实质信号及病灶-肝脏|CNR|均显著增加(P<0.001)。动脉期、门脉期和平衡期所有病灶符合应用常规含钆(Gd)对比剂时的强化表现和特征;延迟20min肝实质期扫描时,肝脏局灶性结节增生呈等信号-高信号,1个肝细胞肝癌呈相对高信号,其余肝囊肿、肝细胞肝癌、胆管细胞癌、肝脏转移性肿瘤、淋巴上皮瘤样癌、退变结节、肝细胞腺瘤、肝血管瘤和肝脏炎性假瘤等均呈相对低信号。结论:Gd-EOB-DTPA动态增强扫描与延迟肝实质期扫描联合应用,可以提供病变形态、血供、细胞来源及功能等更多相关信息,从而提高诊断信心及诊断准确性。     

Fatty metamorphosis in hepatocellular carcinoma: radiologic features in 10 cases

We describe the sonographic, CT and angiographic findings in 10 cases of hepatocellular carcinoma in which extensive fatty metamorphosis occurred within the tumors. Fatty change was diffuse in smaller tumors (less than 3.5 cm) and focal in larger tumors (greater than 3.5 cm). Fatty metamorphosis characteristically caused a low-attenuation area on CT (less than -10 H) and a highly echogenic area on sonography. The sonographic appearance of small hepatocellular carcinomas with fatty metamorphosis was identical to the findings in cavernous hemangioma or focal fatty change of the liver. CT correctly revealed the presence of fat in these hepatocellular carcinomas. In these cases, hepatic arteriography showed no tumor stain; however, CT arteriography (dynamic CT during injection of contrast medium into the hepatic artery) was useful in showing the tumor, its capsule, and its internal septa. In the diagnosis of large hepatocellular carcinoma, the presence of intratumoral fat is not likely to be problematic, but small tumors that are diffusely infiltrated by fat must be distinguished from such benign conditions as focal fatty change, lipoma, and angiomyolipoma.     

Hepatocellular adenoma: multiphasic CT and histopathologic findings in 25 patients

PURPOSE: To evaluate multiphasic computed tomographic (CT) findings of hepatic adenomas and to correlate these findings with those of histopathologic analysis. MATERIALS AND METHODS: Multiphasic helical CT was performed in 25 patients with 44 hepatic adenomas. Nonenhanced scans were obtained in all cases, along with hepatic arterial-dominant phase (HAP) and portal venous-dominant phase (PVP) images at 25-28 and 60-70 seconds after intravenous contrast material injection at 3-5 mL/sec. Twelve patients with 24 adenomas also underwent delayed-phase (5-10-minute) CT. Two independent readers retrospectively reviewed each case for the number of detectable lesions in each CT phase, morphologic features of tumors, and degrees of enhancement. RESULTS: Thirteen patients had solitary adenomas; 12 patients had two or three adenomas. Both observers agreed on the numbers of lesions detected in all cases and in all phases of enhancement. The detection rate for all 44 adenomas per type of examination was as follows: nonenhanced, 86% (38 of 44); HAP, 100% (44 of 44); PVP, 82% (36 of 44), and delayed, 88% (21 of 24). Tumor margins were well defined in 38 adenomas (86%), and the surface was smooth in 42 adenomas (95%). The right hepatic lobe was the only site of adenoma or was a site along with the left lobe in 29 cases (66%). Tumor fat and calcifications were uncommon (three cases [7%] and two cases [5%], respectively). Other than areas of fat, hemorrhage, or necrosis, the adenomas enhanced nearly homogeneously, especially on PVP and delayed-phase scans. Five patients had coexistent hepatic masses, which were focal nodular hyperplasia (n = 3) or hepatocellular carcinoma (n = 2). CONCLUSION: Hepatic adenomas often have characteristic features at multiphasic CT that may allow their distinction from other hepatic masses.     

Effects of prostaglandin E(1) injection through the superior mesenteric artery on the hemodynamics of hepatocellular carcinoma.

OBJECTIVE: The purpose of our study was to assess the effects of portal blood flow on contrast enhancement in hepatocellular carcinoma lesions on CT hepatic arteriography. SUBJECTS AND METHODS: We examined 43 tumors in 39 patients who simultaneously underwent CT during arterial portography and CT hepatic arteriography for examination of liver tumors and then CT hepatic arteriography with prostaglandin E(1) injection via the superior mesenteric artery. All lesions pathologically confirmed to be hepatocellular carcinomas exhibited portal perfusion defects on CT during arterial portography. Changes in CT attenuation, size, and shape of liver tumors visualized on CT hepatic arteriography after intraarterial injection of prostaglandin E(1) were studied. In addition, changes in CT attenuation of the liver parenchyma surrounding the tumor were measured. RESULTS: The CT attenuation increased significantly after injection of prostaglandin E(1) in 91% (39/43) of the lesions (mean increase from 176.4 to 206.6 H; p = 0.0006, paired t test). The size and shape of the enhanced area generally did not change. The CT attenuation of the liver parenchyma surrounding each liver tumor significantly decreased in 58% (25/43) of the hepatocellular carcinoma lesions (mean decrease from 94.8 to 92.0 H; p = 0.0166, paired t test) and lesion conspicuity increased in 91% (39/43) of the tumors. CONCLUSION: Lesion conspicuity on CT hepatic arteriography between hepatocellular carcinoma and the surrounding liver parenchyma increased because of greater portal perfusion after the prostaglandin E(1) injection.     

Diagnosis of coexistent hepatic tumors of different kinds: a challenge from CT and MR imaging

Three cases of multiple, different liver tumors in the same patient were examined with CT and MR imaging. Two patients with coexistent hepatocellular carcinoma and cavernous hemangioma were correctly diagnosed by the following characteristic findings on dynamic CT and/or MR images; spreading and markedly prolonged enhancement in cavernous hemangioma, and the presence of capsule and/or transient diffuse enhancement in hepatocellular carcinoma. The third case of hepatocellular carcinoma and cholangiocarcinoma showed typical findings of hepatocellular carcinoma in one tumor and unusual complex enhancement in the other. CT and MR imaging may enable correct diagnosis to be made even in patients with multiple liver tumors of different kinds.     

CT arteriography of hepatic tumors]

The liver has dual blood supply from the portal vein and hepatic artery. Computed tomographic findings of hepatic neoplasms are greatly influenced by hepatic blood flow, and abnormal portal and hepatic arterial blood flow needs to be examined separately by CT arteriography (CTA) and CT during arterial portography (CTAP). Both CTA and CTAP have advantages over conventional CT in that they can provide greater contrast enhancement of hepatic tumors by injecting contrast material directly into the hepatic or superior mesenteric arteries. The methods of CTA and CTAP are described. CTA and CTAP were useful in the detection of small hepatic lesions, evaluation of changes in hepatic parenchymal blood flow, and evaluation of portal flow in hepatocellular carcinoma, which contribute to the classification of HCC. In conclusion, CTA and CTAP were indispensable in selecting a therapeutic approach.     

Hepatic scar in a case of healed candidiasis showing prolonged enhancement on CT

A patient with acute myelocytic leukemia recovering from hepatic candidiasis after long-term administration of amphotericin B had large scar in the liver which showed prominent prolonged enhancement on postcontrast CT. Prolonged enhancement can occur in regions other than hepatic masses.     

螺旋CT双期或三期扫描对肝脏占位性病变的诊断

目的：分析肝脏螺旋CT双期或三期扫描表现，探讨其对原发性肝癌、肝转移瘤、肝血管瘤的诊断及鉴别诊断的意义。方法：经临床证实25例，均作螺旋CT平扫、动脉期、门脉期及部分平衡期和延迟期扫描，并分析螺旋CT多期扫描表现。结果：原发性肝癌动脉期明显强化而肝脏无强化，形成鲜明的对比，门脉期呈相对低密度或恢复到平扫时表现。肝血管瘤CT特征为动脉期呈边缘性环状、结节样强化，门脉期病灶边缘强化向中心强化并充满病灶呈高密度，平衡期呈等密度或低密度肝转移瘤表现多样化，周边强化或不均匀强化或不强化。结论：螺旋CT双期或三期扫描已作为对肝脏占位性病变的主要检查方法，并作为常规。     

Dynamic contrast-enhanced CT imaging of hepatocellular carcinoma in cirrhosis: feasibility of a prolonged dual-phase imaging protocol with tracer kinetics modeling

Dynamic contrast-enhanced (DCE) CT imaging of four patients with hepatocellular carcinoma (HCC) was performed using a dual-phase imaging protocol designed with initial rapid dynamic imaging to capture the initial increase in contrast medium enhancement in order to assess perfusion, followed by a delayed imaging phase with progressively longer intervals to monitor subsequent tissue enhancement behaviour in order to assess tissue permeability. The DCE CT images were analysed using a dual-input two-compartment distributed parameter model to yield separate estimates for blood flow and permeability, as well as fractional intravascular and extravascular volumes. The HCCs and surrounding cirrhotic liver tissues were found to exhibit enhancement curves that can be appropriately described by two distinct compartments separated by a semipermeable barrier. Early contrast arrival was also found for HCC as compared with background liver. These findings are consistent with the current understanding of sinusoidal capillarization and hepatocarcinogenesis.     

Hepatic tumors: dynamic MR imaging

Thirty-six patients with hepatic tumors (28 hepatocellular carcinomas, seven cavernous hemangiomas, one metastatic tumor) were examined with serial magnetic resonance (MR) imaging, after a bolus intravenous injection of 0.05 mmol/kg gadolinium-diethylenetriaminepentaacetic acid. A typical MR imaging pattern for hemangiomas (present in five of seven cases [71.4%]) was a lesion of diminished signal intensity on precontrast images, peripheral contrast enhancement during the bolus dynamic phase, and complete fill-in of high signal intensity on delayed scan images. Twenty-eight hepatocellular carcinomas showed a variety of contrast enhancement patterns during the dynamic phase. In 21 patients (75%), there was no area of high signal intensity within the tumor on the delayed phase. A peripheral halo with delayed enhancement was noticed in 12 patients (42.8%) Histologic correlation in hepatocellular carcinomas showed that the degree of contrast enhancement corresponded to tumor vascularity and that the peripheral halo corresponded to fibrous capsular structure.     

CT appearance of hepatic parenchymal changes after percutaneous microwave coagulation therapy for hepatocellular carcinoma

PURPOSE: The purpose of this study was to evaluate the changes in the CT appearance of the hepatic parenchyma surrounding the necrotic area in the early period after percutaneous microwave coagulation therapy (PMCT) for hepatocellular carcinoma (HCC). METHOD: We reviewed enhanced CT scans obtained before and within 2 weeks, at 1 month, and at 3 months after PMCT of 61 lesions in 47 patients with HCC. RESULTS: On dynamic CT, early enhancement of the hepatic parenchyma around the treated area was a frequent finding within 1 (87%) or 2 (68%) weeks after PMCT, but such enhancement disappeared on follow-up. Arterioportal shunts were also demonstrated by enhanced CT after treatment (21% at < or =2 weeks), and these shunts tended to persist for >1 month. CONCLUSION: We should evaluate the effect of PMCT by performing dynamic enhanced CT not only within 2 weeks to determine the end-point of treatment but also at 1 month or more after finishing treatment for definite assessment of tumor necrosis.     

MRI动态增强鉴别复发性肝癌和放射性肝损伤

目的 :探讨立体定向放射治疗原发性肝癌后MRI在鉴别复发性肝癌和放射性肝损伤的诊断价值。方法 :12名原发性肝癌立体定向放射治疗后怀疑复发的患者行MRT1WI、T2 WI和T1WI动态增强检查 ,分别测量复发性肝癌和放射性肝损伤的T1WI、T2 WI的信噪比及强化程度 ,并进行统计学分析。结果 :复发性肝癌和放射性肝损伤在T1WI和T2 WI上信号表现相似 ,两者SNR对比差异无显著性意义。增强扫描后 ,复发性肝癌在动脉期强化 ,静脉期及延迟期呈低信号 ,强化持续时间短 ;放射性肝损伤动脉期强化 ,强化持续时间长 ,静脉期及延迟期亦呈高信号 ,两者明显不同。结论 :MRI动态增强可有效的鉴别复发性肝癌和放射性肝损伤     

The dynamic magnetic resonance study of focal liver lesions by FLASH sequences with bolus intravenous gadolinium-DTPA]

Thirty-five patients with hepatic hemangioma (n = 12), metastasis (n = 10), hepatocellular carcinoma (HCC) (n = 10) and focal nodular hyperplasia (n = 3) were examined with the fast low-angle shot (FLASH) technique and an intravenous bolus injection of Gd-DTPA. In order to differentiate the lesions, the following criteria were used: a) pre Gd-DTPA intensity of lesions; b) post Gd-DTPA patterns of contrast enhancement. On the basis of these criteria, an unquestionable differential diagnosis could be made. Hemangiomas were characterized by an hypointense mass before Gd-DTPA, by peripheral contrast enhancement and by subsequent continuous hyperintense fill-in; thus, hemangiomas were visualized as hyperintense lesion during the late phase. Before contrast administration hypovascular metastases appeared as hypointense; they were characterized by delayed uptake of contrast agent. HCCs were hyperintense lesions before contrast administrations; then, quick contrast enhancement and rapid decrease in signal intensity were observed with visualization of a hyperintense ring due to the capsule. Finally, focal nodular hyperplasia appeared isointense or hypointense relative to normal liver on precontrast scans; the lesions were enhanced transiently with subsequent quick dismission of contrast agent. This initial experience suggests dynamic contrast-enhanced MR imaging as an effective method to improve the differential diagnosis among hepatic tumors when precontrast T2-weighted images are equivocal.