Focal nodular hyperplasia-like nodule with reduced expression of organic anion transporter 1B3 in alcoholic liver cirrhosis

We report a patient with alcoholic liver cirrhosis who had a 15 mm focal nodular hyperplasia (FNH)-like nodule in the liver. This FNH-like nodule was diagnosed as hepatocellular carcinoma (HCC) mainly based on hypervascularity during the hepatic arterial phase, washout pattern during the equilibrium phase and low signal intensity during the hepatobiliary phase in gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced MRI; it was surgically resected. Its histology exhibited hepatocyte hyperplasia, fibrous septa containing unpaired small arteries accompanied by reactive bile ductules, remarkable iron deposits and sinusoidal capillarization, and was compatible with the diagnosis of an FNH-like nodule. When we analyzed the images of the present nodule retrospectively, low signal intensity on in-phase and isosignal intensity on opposed-phase T1-weighted MRI may have reflected iron deposits in the FNH-like nodule. In addition, a low signal intensity on T2-weighted MRI and no detection in diffusion-weighted MRI may help in distinguishing FNH-like nodules from HCC, since these image findings are inconsistent with typical HCC. Immunohistochemical analysis revealed a markedly reduced expression of organic anion transporter (OATP) 1B3 in this nodule, which implied decreased Gd-EOB-DTPA uptake by hepatocytes and accounted for the low signal intensity during the hepatobiliary phase on Gd-EOB-DTPA-enhanced MRI. To the best of our knowledge this is the first report in which an FNH-like nodule was assessed for OATP1B3 expression.     

Hereditary hemorrhagic telangiectasia with multiple hepatic and pulmonary nodular lesions

A 50-year-old female visited the hospital for further evaluation of multiple pulmonary and hepatic nodules. First, she visited her primary physician for general fatigue due to anemia. She had recurrent epistaxis, and her mother had suffered from hereditary hemorrhagic telangiectasia (HHT). Telangiectasias were present in the stomach. This patient was diagnosed with HHT. Computed tomography (CT) revealed multiple pulmonary and hepatic nodules. The pulmonary nodules were due to bleeding from arteriovenous malformations of the lung. Abdominal CT and angiography showed a dilated and meandering hepatic artery, arteriovenous shunts and multiple hepatic nodules. Gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) showed enhancement in the early dynamic phase and in the liver-specific phase. A liver tumor biopsy of a hepatic nodule showed nodular regenerative hyperplasia (NRH). This report presents a case of HHT with multiple pulmonary and hepatic nodular lesions. Gd-EOB-DTPA-enhanced MRI was useful for making a diagnosis of NRH.     

Focal liver lesions detection and characterization: The advantages of gadoxetic acid-enhanced liver MRI

Since its clinical introduction, several studies in literature have investigated gadolinium ethoxybenzhyl diethylenetriaminepentaacetic acid or gadoxetic acid(Gd-EOB-DTPA) properties. Following contrast injection, it provides dynamic vascular phases(arterial, portal and equilibrium phases) and hepatobiliary phase, the latter due to its uptake by functional hepatocytes. The main advantages of Gd-EOB-DTPA of focal liver lesion detection and characterization are discussed in this paper. Namely, we focus on the possibility of distinguishing focal nodular hyperplasia(FNH) from hepatic adenoma(HA), the identification of early hepatocellular carcinoma(HCC) and the pre-operative assessment of metastasis in liver parenchyma. Regarding the differentiation between FNH and HA, adenoma typically appears hypointense in hepatobiliary phase, whereas FNH is isointense or hyperintense to the surrounding hepatic parenchyma. As for the identification of early HCCs, many papers recently published in literature have emphasized the contribution of hepatobiliary phase in the characterization of nodules without a typical hallmark of HCC. Atypical nodules(no hypervascularizaton observed on arterial phase and/or no hypovascular appearance on portal phase) with low signal intensity in the hepatobiliary phase, have a high probability of malignancy. Finally, regarding the evaluation of focal hepatic metastases, magnetic resonance pre-operative assessment using gadoxetic acid allows for more accurate diagnosis.     

肝细胞癌癌前结节影像学特征的研究进展

肝细胞癌(HCC)发生是一个多步骤过程,在其发展中检测出HCC癌前病变和进展期HCC,对预测肿瘤行为、判断病变程度、采用最佳治疗策略、改善患者生存至关重要。肝脏成像技术的快速进展和广泛应用,尤其是肝细胞特异性对比剂钆塞酸二钠MRI(Gd-EOB-DTPA MRI)可提供肝结节血管变化、肝细胞功能信息,能够精确区分肝硬化再生结节、低度异型增生结节、高度异型增生结节、早期HCC(early HCC)和HCC,从而进行恶性进展的风险度分层。现综述Gd-EOB-DTPA MRI在HCC早期诊断中的价值,分析HCC多步发展过程中的关键概念,以及癌前病变最终可能转化成典型HCC的影像学表现。     

Hepatocellular carcinoma in a patient with focal nodular hyperplasia

BackgroundFocal nodular hyperplasia is an uncommon liver tumour that typically requires no therapeutic intervention.Case outlineA 43-year-old woman with a 20-year history of oral contraceptive use presented with symptomatic bilateral liver masses. Biopsy revealed hepatocellular carcinoma in the right hemiliver and focal nodular hyperplasia in the left hemiliver.At operation,the patient was noted to have multiple liver nodules bilaterally, and all intraoperative biopsies were consistent with focal nodular hyperplasia including a biopsy taken from the region that demonstrated carcinoma preoperatively. Because of the earlier biopsy results and the patient''s preoperative symptoms, a right hemihepatectomy was performed. Final pathology revealed hepatocellular carcinoma directly adjacent to an area of focal nodular hyperplasia, as well as multiple other areas of hyperplastic liver tumour.DiscussionAlthough focal nodular hyperplasia is believed to be benign, few studies have followed patients with this tumour beyond three years. Longer-term follow-up studies are needed to determine the natural history of focal nodular hyperplasia, potentially focussing on a subset of patients with either diffuse tumours or prolonged oral contraceptive use.     

Hepatocellular carcinoma occurring in hepatobiliary fibropolycystic disease

Congenital hepatic fibrosis (CHF) and bile duct hamartomas (von Meyenburg complexes) are hepatobiliary fibropolycystic diseases. There have been several reports of liver neoplasias arising in hepatobiliary fibropolycystic diseases. However, most of them were cholangiocarcinomas and cases involving hepatocellular carcinoma (HCC) are rare. A 51‐year‐old woman was found to have multiple hepatic tumors by ultrasonography and enhanced computed tomography (CT) during a regular work‐up for the recurrence of lung cancer and thyroid cancer, which had been surgically removed 4 and 3 years ago, respectively. Nodules were observed at S3, S5, and S6 (2 cm in diameter). All of the nodules were hyperattenuated at the early arterial phase, and the main tumor at S5 showed hypoattenuation at the delayed phase on dynamic CT and magnetic resonance imaging (MRI). HCC was suspected from these findings. She also suffered from multiple small cystic lesions in the liver. The surgically removed liver showed HCC arising in CHF, which is a rare histological finding.     

Hypervascular Liver Nodules in Heavy Drinkers of Alcohol

Background: Three cases of hypervascular nodules in the liver, without hepatitis B or C virus infection and with a history of alcohol abuse (120 ml/day for 15 to 30 years), are presented.
Results: Ultrasound examination revealed hypoechoic nodules in segment 6 (2 cm in diameter, case 1), in the right and left lobes (1–2 cm multiple type, case 2), and in segment 4 (4 cm, case 3). Hepatic angiography and computed tomography during arteriography revealed hypervascular nodules in the three cases. First, hepatocellular carcinoma, focal nodular hyperplasia, hemangioma, hemangioendothelioma, inflammatory pseudotumor, and pseudolymphoma were diagnostically differentiated. Histologically, there was no evidence of hepatocellular carcinoma or of any of the pathologies considered in the differential diagnosis by imaging studies. In case 1, the lesion was composed of an irregular, thin, trabecular-patterned hepatic acinus with slighter hypercellularity than in the nonnodular area. In cases 2 and 3, the lesions were composed mainly of fibrosis without hyperplasia, showing stellate scar–like fibrosis septa dividing the nodule. Marked pericellular fibrosis, neutrophilic infiltration, and Mallory bodies in the cytoplasm were also observed. In cases 1 and 2, small unpaired arteries explaining the hypervascularity of the nodules were observed.
Conclusion: These hypervascular nodules were classified as regenerative, not neoplastic, nodules according to the classification of the International Working Party.     

钆塞酸二钠增强磁共振扫描诊断肝脏局灶性病变研究*

目的 通过与手术后组织病理学诊断结果比较,观察钆塞酸二钠（Gd-EOB-DTPA）增强磁共振成像（MRI）对肝脏局灶性病变（FLL）的诊断价值。方法 我院收治的FLL患者68例,接受Gd-EOB-DTPA增强MRI检查,与术后组织病理学诊断比较检查结果的正确性。结果 68例FLL患者经术后组织病理学检查诊断为肝细胞癌36例,肝内胆管细胞癌6例,混合型肝癌8例,肝局灶性结节性增生12例,肝血管平滑肌脂肪瘤4例,非FLL 2例,而Gd-EOB-DTPA增强MRI诊断FLL 64例,其中肝细胞癌37例,肝内胆管细胞癌7例,混合型肝癌4例,肝局灶性结节性增生14例,肝血管平滑肌脂肪瘤2例,非FLL 4例。增强MRI诊断FLL的Kappa值为0.7,其灵敏度为97.1%,特异度为100.0%,阳性预测值为100.0%,阴性预测值为50.0%。结论 采取Gd-EOB-DTPA增强MRI检查对FLL诊断具有较高的灵敏度和特异度,临床应重视其诊断价值。     

Expression of OATP1B3 determines uptake of Gd-EOB-DTPA in hepatocellular carcinoma

Background  Gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) is an MRI contrast agent with perfusion and hepatoselective properties. The purpose of the study was to examine uptake of Gd-EOB-DTPA in the hepatobiliary phase in hepatocellular carcinoma (HCC). Methods  A retrospective analysis of 22 patients with HCC who underwent preoperative Gd-EOB-DTPA-enhanced MRI was performed. Enhancement ratios (ERs) and expression levels of the organic anion transporter (OATP) 1B3 protein were examined. Results  Gd-EOB-DTPA accumulated in the hepatobiliary phase in 6 of the 22 cases. All 6 Gd-EOB-DTPA-positive cases were moderately differentiated HCC, but 11 other moderately differentiated HCCs did not show Gd-EOB-DTPA uptake. Histopathologically, 4 Gd-EOB-DTPA-positive HCCs and 5 Gd-EOB-DTPA-negative HCCs produced bile. HCCs with Gd-EOB-DTPA uptake overexpressed OATP1B3 compared with HCCs without Gd-EOB-DTPA uptake, and OATP1B3 levels were significantly correlated with ERs (r = 0.91, P < 0.0001). Conclusions  Uptake of Gd-EOB-DTPA in HCC is determined by expression of OATP1B3 rather than by tumor differentiation or bile production.     

Images of Sonazoid-enhanced ultrasonography in multistep hepatocarcinogenesis: comparison with Gd-EOB-DTPA-enhanced MRI

Background

Little is known about the difference in enhancement patterns of hepatocellular carcinoma (HCC) during multistep hepatocarcinogenesis between the post-vascular phase of Sonazoid-enhanced ultrasonography (SEUS) and hepatobiliary phase of gadolinium ethoxybenzyl diethylenetriamine (Gd-EOB-DTPA)-enhanced MRI, as well as uptakes of Sonazoid and Gd-EOB-DTPA by HCC.

Methods

Seventy patients with 73 histologically proven HCCs (33 hypovascular well-differentiated HCCs and 40 progressed HCCs) and 9 dysplastic nodules (DNs) were enrolled. Enhancement patterns of the lesions on the post-vascular phase of SEUS and hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI were evaluated. Uptakes of Sonazoid and Gd-EOB-DTPA were assessed by Sonazoid enhancement index and EOB enhancement ratio in relation to immunohistochemistry of CD68 and organic anion transporting polypeptide 8 (OATP8), respectively.

Results

On the post-vascular phase of SEUS, none of the 9 DNs and 3 of 33 hypovascular well-differentiated HCCs (9 %) were hypoechoic, whereas 3 of 9 DNs (33 %) and 31 of 33 hypovascular well-differentiated HCCs (94 %) showed hypointensity on the hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI. Of 31 progressed HCCs, 95 and 93 % were hypoechoic and hypointense on the post-vascular phase of SEUS and hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI, respectively. Sonazoid enhancement indexes decreased in progressed HCCs, correlating with lower Kupffer cell numbers (P < 0.001). EOB enhancement ratios decreased in hypovascular well-differentiated and progressed HCCs, as OATP8 expression declined (P < 0.001).

Conclusions

In stepwise hepatocarcinogenesis, uptake of Sonazoid starts decreasing later than that of Gd-EOB-DTPA. Although signal reductions on the post-vascular phase of SEUS or hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI suggest HCC, hypoechoic appearance on the post-vascular phase of SEUS might be HCC-specific, particularly progressed HCC.     

Ultrasound guided fine needle biopsy of early hepatocellular carcinoma complicating liver cirrhosis: a multicentre study

BACKGROUND: Because hepatic cirrhosis is a major risk factor for hepatocellular carcinoma, recent guidelines by the European Association for the Study of the Liver (EASL) on clinical management of hepatocellular carcinoma recommend periodic ultrasound surveillance of cirrhotic patients with immediate workup for nodules >1 cm; an increase in the frequency of screening is considered sufficient for smaller lesions. AIMS: To determine the actual risk of hepatocellular carcinoma associated with the latter lesions and to assess the role of ultrasound guided-fine needle biopsy in their diagnosis. PATIENTS AND METHODS: Data were analysed for 294 new nodular lesions <20 mm, including 48 that were <10 mm, detected during a prospective multicentre study involving ultrasound surveillance of 4375 patients with hepatic cirrhosis. In the absence of alpha fetoprotein (AFP) levels diagnostic of hepatocellular carcinoma, ultrasound guided-fine needle biopsy was performed (n = 274). AFP and fine needle biopsy diagnoses of malignancies (hepatocellular carcinoma and lymphoma) were considered definitive. Non-malignant fine needle biopsy diagnoses (dysplastic or regenerative nodule) were verified by a second imaging study. Diagnoses of hepatocellular carcinoma based on this study were considered definitive; non-malignant imaging diagnoses were considered definitive after at least one year of clinical and ultrasound follow up. RESULTS: Overall, 258/294 (87.6%) nodules proved to be hepatocellular carcinoma, including 33/48 (68.7%) of those < or =10 mm. Overall typing accuracy of ultrasound guided-fine needle biopsy was 89.4%, and 88.6% for lesions < or =10 mm. CONCLUSIONS: In a screening population, well over half of very small nodules arising in cirrhotic livers may prove to be hepatocellular carcinoma, and approximately 90% of these malignancies can be reliably identified with ultrasound guided-fine needle biopsy.     

Multiple liver lesions in a patient with Budd-Chiari syndrome secondary to polycythemia vera

Focal nodular hyperplasia and nodular regenerative hyperplasia are occasionally seen in patients with hepatic venous outflow obstruction as a consequence of circulatory stress in the liver. In addition, neoplastic processes such as hepatic adenoma, hepatocellular carcinoma, and metastatic disease may arise in these patients. Histologic evaluation is necessary when imaging modalities are unable to distinguish these lesions. We present a case of multiple hepatic lesions, suspicious for metastases, in a patient with Budd-Chiari syndrome secondary to polycythemia vera. However, the biopsy findings were consistent with focal nodular hyperplasia. Budd-Chiari syndrome may be associated with multiple nodules of focal nodular hyperplasia, which may be difficult to diagnose radiologically.     

The Sialyl Lewis X expression in hepatocarcinogenesis: potential predictor for the emergence of hepatocellular carcinoma

BACKGROUND/AIMS: Sialyl Lewis X (sLeX), one of the cancer-associated glycoproteins, has been reported to be expressed in both liver tissue from various types of liver disease and hepatocellular carcinoma. In order to clarify sLeX expression during the early stage of hepatocarcinogenesis, we examined sLeX expressions in either liver tissue specimens without any nodular lesions, dysplastic nodules or hepatocellular carcinomas. METHODOLOGY: Immunohistochemical observations were performed using a monoclonal antibody for sLeX. As for the liver tissue specimens, 8 livers without any chronic liver disease and 42 diseased livers were examined, while for the nodular lesions, 5 dysplastic nodules (borderline lesions) and 47 hepatocellular carcinomas were examined in this study. RESULTS: sLeX was not expressed in all 8 normal livers. sLeX was expressed membraneously in 8 of 15 (53%) chronic hepatitic liver tissue specimens, in 8 of 9 (89%) precirrhotic liver tissue specimens and in 16 of 18 (89%) cirrhotic liver tissue specimens. The incidence of sLeX expression on hepatocytes in both pre-cirrhotic and cirrhotic liver tissue was higher than that in chronic hepatitic liver tissue (P < 0.05). The sLeX expression in liver tissue was positive in all 14 liver tissue specimens containing multiple hepatocellular carcinomas, in which at least one of the nodules was a well-differentiated hepatocellular carcinoma regarded as multicentric hepatocellular carcinomas. In 18 of 28 (64%) liver tissue specimens without multicentric hepatocellular carcinomas, sLeX was positive and the difference was statistically significant (P < 0.05). In nodular lesions, sLeX was negative in 5 dysplastic nodules (borderline lesions). In hepatocellular carcinoma, 14 of 47 (30%) hepatocellular carcinoma nodules showed a positive expression. Six of 14 (43%) well-differentiated hepatocellular carcinomas were positive on the cell membrane. Four of 23 (17%) moderately differentiated hepatocellular carcinomas were positive on the cell membrane, while one of 23 (4%) moderately differentiated hepatocellular carcinoma was positive in the cytoplasm. In addition, 3 of 10 (30%) poorly differentiated hepatocellular carcinomas were positive in the cytoplasm. CONCLUSIONS: These results suggested that the sLeX-positive liver tissue specimens possessed a high degree of carcinogenicity and therefore sLeX expression in the diseased liver might be a good predictor for hepatocellular carcinoma emergence. At the same time, the suppression of sLeX occurred at a very early stage of hepatocarcinogenesis. In addition, the phenotype of sLeX was also considered to change during the progression of hepatocarcinogenesis.     

Benign nodular hepatocellular lesions caused by abnormal hepatic circulation: etiological analysis and introduction of a new concept

Abstract Problems in definitive diagnosis and etiology of various benign nodular hepatocellular lesions were evaluated. Of these lesions, focal nodular hyperplasia (FNH), nodular regenerative hyperplasia (NRH), nodular lesions associated with idiopathic portal hypertension (IPH), non‐cirrhotic large regenerative nodules (LRN), hepatocellular adenoma (HA)‐like hyperplastic nodules, and partial nodular transformation (PNT) have been suggested to be related to abnormal hepatic circulation. However, the following points are considered to need further clarification: (i) is the abnormal circulation caused by thrombosis, vasculitis, or congenital anomaly?; (ii) is thrombosis a cause or a result of congestion?; (iii) are impaired blood vessels primarily the portal veins or arteries?; (iv) how are these disorders related to various syndromes, immunological abnormalities and abnormal blood flow of other organs, which are reported to coexist with these lesions often?; and (v) how should non‐typical cases, which differ from typical cases, be interpreted? In addition, a concept that may lead to solving these problems (anomalous portal tract syndrome; a hypothesis that congenital vascular anomaly is the origin of these benign nodular hepatocellular lesions) was introduced.     

Large regenerative nodules and dysplastic nodules in cirrhotic livers: a histopathologic study

In order to reveal the precursor lesion of hepatocellular carcinoma, a histopathologic study was performed on 141 cases of liver cirrhosis with or without hepatocellular carcinoma. Exclusive of primary or metastatic hepatocellular carcinoma nodules, 94 nodular lesions (greater than 5 mm) were detected in 53 cirrhotic livers. They consisted of 83 large regenerative nodules and 11 dysplastic nodules. Besides some common features with those observed in the former type, the dysplastic nodules presented increased cytoplasmic basophilia, nuclear and nucleolar enlargement, nuclear crowding, occasional microacinar formation and proliferation of the hepatocytes within fibrous septa. These changes were not substantial enough to allow the diagnosis of hepatocellular carcinoma. In one case, however, malignant transformation of hepatocytes was suspected because of their pattern of extranodular outgrowth. It is important to recognize these subtle abnormalities in order to define premalignant hepatic lesions. A possible connection between benign large regenerative nodules and dysplastic nodules is also discussed.     

The role of laparoscopic US and laparoscopic US-guided aspiration biopsy in the diagnosis of multicentric hepatocellular carcinoma.

BACKGROUND: Detection of small hepatocellular carcinomas has become possible with improvements in various diagnostic imaging techniques. However, intraoperative US can detect lesions not visualized by any preoperative imaging study in which case it is difficult to determine whether the lesion is a hepatocellular carcinoma. METHODS: Nodular lesions detected by laparoscopic US in 186 patients with hepatocellular carcinoma were examined and we evaluated the diagnostic ability of laparoscopic US to detect multicentric hepatocellular carcinoma. RESULTS: One hundred thirty-four new nodular lesions were detected by laparoscopic US in 64 (34.4%) of 186 patients. Aspiration biopsy under laparoscopic US guidance was performed on the 134 nodules, and 28 nodules in 23 (12.4%) of the 186 patients were histologically diagnosed as hepatocellular carcinoma. Of these 23 patients, 18 had been diagnosed with solitary hepatocellular carcinoma before laparoscopic US. One hundred six of the newly detected lesions were initially diagnosed as noncarcinomatous nodules, but the diagnosis of 10 of these lesions was changed to hepatocellular carcinoma during follow-up that was as long as 96 months. CONCLUSIONS: Laparoscopic US is useful in the initial diagnosis of hepatocellular carcinoma and impacts treatment selection by more accurately defining the presence of multicentric hepatocellular carcinomas.     

Adenomatous hyperplasia in the vicinity of small hepatocellular carcinoma.

The nodular lesions seen in the noncancerous areas of the 80 consecutively resected small hepatocellular carcinoma associated with cirrhosis were pathomorphologically studied. A total of 51 nodular lesions were found, and they were classified into the following four groups: large regenerative nodule (30 nodules), adenomatous hyperplasia (12 nodules), atypical adenomatous hyperplasia (4 nodules) and adenomatous hyperplasia containing cancerous foci (5 nodules). Grossly, all large regenerative nodules were well demarcated, but some of the adenomatous hyperplasia group were vaguely nodular. Atypical adenomatous hyperplasia and adenomatous hyperplasia containing cancerous foci accounted for 43% of the adenomatous hyperplasia group found in the vicinity of the 16 resected hepatocellular carcinoma (20%) out of 80 cases. The mean size (+/- S.D.) of the adenomatous hyperplasias containing cancerous foci, 15.8 +/- 2.2 mm, was significantly larger than 10.1 +/- 2.6 mm of the adenomatous hyperplasias p less than 0.01). All adenomatous hyperplasias containing cancerous foci and 75% of the atypical adenomatous hyperplasias demonstrated a marked fatty change, but none of the large regenerative nodules were accompanied by any fatty changes. This study demonstrated the morphological transition from adenomatous hyperplasia to hepatocellular carcinoma that was suggestive of multistep hepatocarcinogenesis. As a result, it is predicted that approximately 20% of all hepatocellular carcinomas may have the potential for being of multicentric origin and that approximately 40% of adenomatous hyperplasias may undergo malignant transformation, but it is difficult to estimate the exact number of incidences. The presence of varying degrees of fatty change may be one of the significant morphological markers for a malignant transformation from adenomatous hyperplasia to hepatocellular carcinoma.(ABSTRACT TRUNCATED AT 250 WORDS)     

Large regenerative nodule perfused by the portal vein

In a 42-year-old Japanese woman with esophageal varices, abdominal ultrasound (US) demonstrated a hyperechoic lesion 3 cm in diameter in segment 4 (S4). This nodular lesion had high intensity on T1-weighted magnetic resonance imaging (MRI), low intensity on T2, and very high intensity on superparamagnetic iron oxide (SPIO) enhanced MRI. Angiography showed sparse distribution of arterial branches and dense distribution of portal branches in S4. Meandering, thin arteries were seen in the peripheral area of the right lobe. The second branches of the portal vein were hardly visualized anywhere in the liver. Computed tomography arterioportography (CTAP) revealed portal blood flow dominance in this nodular lesion. There was no evidence of ischemic liver damage, such as thromboembolic episodes, laboratory data of liver damage, coagulation abnormalities etc. Therefore this abnormality was more likely to be caused by anomalous changes than thrombotic changes. Needle biopsy revealed no atypical cells. Two years later, the nodule size was reduced to 1.9 cm, showing its benign nature. Based on these findings, this lesion was classified as a new type of large regenerative nodule (LRN) associated with anomalies in the portal veins and arteries. This is the first report of an LRN of this size in which portal vein perfusion was dominant. Moreover, this lesion was difficult to differentiate from hepatocellular carcinoma (HCC) by imaging. Analysis of the images and pathological features of this case would contribute to a better understanding of the pathogenesis of nodular lesions of the liver.     

A case of hepatocellular carcinoma arising within large focal nodular hyperplasia with review of the literature

Focal nodular hyperplasia (FNH) is a relatively rare benign hepatic tumor, usually presenting as a solitary lesion; however, multiple localizations have also been described. The association of FNH with other hepatic lesions, such as adenomas and haemangiomas has been reported by various authors. We herein report a case of a hepatocellular carcinoma arising within a large focal nodular hyperplasia, in a young female patient.     

A case of hepatocellular carcinoma arising within large focal nodular hyperplasia with review of the literature

INTRODUCTIONFocal nodular hyperplasia(FNH)is a relatively rare benign liver tumor,often asymptomatic and discovered incidentally[1,2].It occurs in both men and women,but shows a predilection for young women.FNH presents as a solitary lesion in70%of the ca…