The malignant transformation of liver cell adenomas

Benign Hepatic Tumors: From Incidental Imaging Finding to Clinical Management

Benign hepatic tumors (BHTs) are commonly detected as incidental finding mainly due to the frequent utilization of imaging modalities, including ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI). Rigorous clinical evaluation, with a particular focus on chronic liver disease (CLD) or risk factors for CLD, medication history, physical examination for signs of CLD, blood tests, and a review of past liver radiology constitute the initial steps in the evaluation of a new liver lesion. Further, contrast-enhanced imaging using US, CT and MRI, can be used depending on the clinical scenario and their availability. The contrast-enhanced MRI provides detailed tissue assessment while avoiding exposure to radiations, although it is scarcely available and expensive. While the liver tissue-specific protocols ensure precise diagnosis, a biopsy is recommended in selected or doubtful cases. Further, most BHTs, such as hemangiomas, are harmless and do not require special management or follow-up, the hepatic adenomas and large or atypical cases of focal nodular hyperplasia are clinically relevant and require management/follow-up. In such cases, it is favorable to have a multidisciplinary team approach, which includes hepatologist, radiologist, hepatobiliary surgeon, and pathologist. This review aims to elaborate the current understanding of BHTs, and provide a practical guidance for primary care and practitioners of family and internal medicine for the disease evaluation and management.

Unclassified hepatocellular adenoma with histological brown pigment deposition and serum PIVKA-II level elevation: a case report

Background

Hepatocellular adenoma (HCA) is conventionally considered a rare benign liver tumor, but advanced studies have revealed that HCA is heterogeneous, and may include a type that is prone to malignant transformations. Differentiation between well-differentiated hepatocellular carcinoma and focal nodular hyperplasia is necessary to diagnose hepatocellular adenoma through imaging; however, the tumor marker of hepatocellular carcinoma, protein induced by vitamin K absence, or antagonist II (PIVKA-II), is rarely positive in hepatocellular adenoma.

Case presentation

A 44-year-old woman presented to our hospital with complaints of loss of appetite and weight loss. Multidetector row computed tomography revealed a liver tumor (diameter, 80 mm) that was enhanced in the arterial phase. Her serum PIVKA-II level was very high (3327 mAU/mL). Based on the enlargement of the mass and the results of the diagnostic imaging, hepatocellular adenoma or hepatocellular carcinoma was suspected, and we considered the possibility of a malignant transformation due to the high level of serum PIVKA-II; thus, we performed hepatectomy. Histological examination showed brown pigment deposition in the hepatocytes, which was determined to be lipofuscin granules. Based on immunohistochemical findings, the diagnosis was unclassified hepatocellular adenoma. Immunohistochemical examinations revealed that the adenoma cells in the tumor were positive for PIVKA-II. Her serum PIVKA-II level returned to normal after the resection.

Conclusions

We present a case of unclassified hepatocellular adenoma with brown pigment deposition and elevation of serum PIVKA-II level. For the differentiation of liver tumors with high levels of PIVKA-II and hypervascular mass, hepatocellular adenoma should be considered.

Liver adenomatosis in patients with hepatocyte nuclear factor-1 alpha maturity onset diabetes of the young (HNF1A-MODY): Clinical, radiological and pathological characteristics in a French series

BACKGROUND

Liver adenomatosis (LA) is a rare disease resulting from biallelic inactivation of the hepatocyte nuclear factor-1 alpha (HNF1A) gene, which induces the proliferation of adenoma cells in liver parenchyma. Liver adenomatosis has only been documented in case reports from patients carrying a HNF1A germline mutation. We have evaluated the frequency of LA among a large cohort of patients with HNF1A-maturity onset diabetes of the young (MODY), previously termed "MODY3," and herein describe its clinical, radiological, and pathological characteristics.

METHODS

In all, 137 HNF1A-MODY subjects from 74 families were screened by liver ultrasonography in 13 centers, and 15 additional cases of LA were later included in the series. Liver adenomatosis was confirmed by liver computed tomography, magnetic resonance imaging (MRI), and/or histopathology.

RESULTS

Among 137 carriers of an HNF1A mutation, 9 patients (6.5%) from seven families were diagnosed with LA. Diabetes mellitus was present in 87.5% of patients with LA. In 25% of patients, LA was diagnosed due to intra-abdominal or intratumoral bleeding. Liver biochemistry was near normal in all patients. Liver imaging showed adenomas of various sizes and numbers. On MRI, most nodules had the radiological characteristics of steatotic adenomas. Histopathological confirmation of LA was available in 13 cases, and these adenomas were mostly steatotic. Surgery was initially performed in 37.5% of patients, and liver disease progression was observed in 30%. No disease progression was observed in 14 pregnancies.

CONCLUSIONS

The frequency of LA in a cohort of screened HNF1A-MODY patients and the high incidence of LA progression and/or hemorrhage warrants systematic screening for liver adenomatosis in HNF1A-MODY families.

Ultrasound Imaging of Hepatocellular Adenoma Using the New Histology Classification

Hepatocellular adenoma is a rare benign liver tumor. Predisposing factors include hepatic storage diseases and some genetic conditions. A new histology-based classification has been proposed but to date, the corresponding ultrasound imaging features have not been reported. Here we review the new classification scheme and discuss the corresponding features on contrast-enhanced ultrasound imaging.

A practical diagnostic approach to hepatic masses

The differential diagnosis of hepatic mass lesions is broad and arriving at the right diagnosis can be challenging, especially on needle biopsies. The differential diagnosis of liver tumors in children is different from adults and is beyond the scope of this review. In adults, the approach varies depending on the age, gender, and presence of background liver disease. The lesions can be divided broadly into primary and metastatic (secondary), and the primary lesions can be further divided into those of hepatocellular origin and nonhepatocellular origin. The first category consists of benign and malignant lesions arising from hepatocytes, while the second category includes biliary, mesenchymal, hematopoietic, and vascular tumors. Discussion of nonepithelial neoplasms is beyond the scope of this review. The hepatocytic lesions comprise dysplastic nodules, focal nodular hyperplasia, hepatic adenoma, and hepatocellular carcinoma, and the differential diagnosis can be challenging requiring clinicopathological correlation and application of immunohistochemical (IHC) markers. Liver is a common site for metastasis, sometimes presenting with an unknown primary site, and proper workup is the key to arriving at the correct diagnosis. The correct diagnosis in this setting requires a systematic approach with attention to histologic features, imaging findings, clinical presentation, and judicious use of IHC markers. The list of antibodies that can be used for this purpose keeps on growing continually. It is important for pathologists to be up to date with the sensitivity and specificity of these markers and their diagnostic role and clinical implications. The purpose of this review is to outline the differential diagnosis of hepatic masses in adults and discuss an algorithmic approach to make a right diagnosis.

Long-term follow-up of hepatic adenoma and adenomatosis: analysis of size change on imaging with histopathological correlation

AIM

To analyse the change in size on follow-up of hepatic adenomas (HAs) and adenomatosis, and to investigate the relationship of imaging features with size change.

MATERIALS AND METHODS

The study included 44 patients (142 lesions) who underwent magnetic resonance imaging (MRI) or computed tomography (CT) for diagnosis and follow-up of HA. The imaging features and percentage change in maximum tumour dimension were observed over a follow-up duration of up to 139 months.

RESULTS

With an average follow-up of 43 months, 37% lesions decreased in size, 58% were stable, 4% increased; one lesion regressed completely. Adenomas were stratified into size groups (<3, 3-5, and ≥5 cm). Size change among the three groups was similar (p>0.05). Percent size change was different for lesions followed for ≤12 months (-7.2%) compared with lesions followed for 13-60 months (-20.5%), and those followed for ≥60 months (-23.5%; p<0.05); there was no difference between lesions followed for 13-60 months and ≥60 months (p=0.523). Baseline size and percent size change was similar between the hepatocyte nuclear factor 1α-inactivated HA (HA-H) and inflammatory HA (HA-I) subtype (p>0.05).

CONCLUSION

Most adenomas were either stable or regressed on follow-up. Size change was independent of baseline size. After an initial size decrease within 5 years, no further size reduction was noted on extended follow-up. The percent size change in the HA-H and HA-I subtype was similar.

Simultaneous Presence of Focal Nodular Hyperplasia and Hepatocellular Carcinoma: Case Report and Review of the Literature

Focal nodular hyperplasia (FNH) is an infrequent benign tumor of the liver that is generally believed to have no potential for malignant transformation; the coexistence of FNH and hepatocellular carcinoma (HCC) has seldom been reported. Here we describe an exceptional case of simultaneous FNH and HCC in the same patient and discuss the clinical and therapeutic management of FNH on the basis of a review of the literature.

Hepatocellular Adenomas: Morphology and Genomics

Hepatocellular adenomas (HCAs) are rare benign tumors. This single entity has been split into 3 subtypes corresponding to specific mutations: HNF1α-inactivated HCA; inflammatory HCA related to different mutations, all leading to activation of STAT3 pathway; and β-catenin-activated HCA related to CTNNB1 mutations. The risk of malignant transformation depends on the level of β-catenin activation, reported mainly for exon 3, including S45. It is possible using specific immunohistochemical markers to identify the 3 different HCA subtypes and the level of β-catenin activation. Fewer than 10% of HCAs remain unclassified.

European experience of 573 liver resections for hepatocellular adenoma: a cross-sectional study by the AFC-HCA-2013 study group

BACKGROUND

Hepatocellular adenoma (HCA) is a benign hepatic lesion that may be complicated by bleeding and malignant transformation. The aim of the present study is to report on large series of liver resections for HCA and assess the incidence of hemorrhage and malignant transformation.

METHODS

A retrospective cross-sectional study, from 27 European high-volume HPB units.

RESULTS

573 patients were analyzed. The female: male gender ratio was 8:2, mean age: 37 ± 10 years. Of the 84 (14%) patients whose initial presentation was hemorrhagic shock (Hemorrhagic HCAs), hemostatic intervention was urgently required in 25 (30%) patients. No patients died after intervention. Tumor size was >5 cm in 74% in hemorrhagic HCAs and 64% in non-hemorrhagic HCAs (p < 0.001). In non-hemorrhagic HCAs (n = 489), 5% presented with malignant transformation. Male status and tumor size >10 cm were the two predictive factors. Liver resections included major hepatectomy in 25% and a laparoscopic approach in 37% of the patients. In non-hemorrhagic HCAs, there was no mortality and major complications occurred in 9% of patients.

DISCUSSION

Liver resection for HCA is safe. Presentation with hemorrhage was associated with larger tumor size. In males with a HCA >10 cm, a HCC should be suspected. In such situation, a preoperative biopsy is preferable and an oncological liver resection should be considered.

[Extracapsular hepatic adenoma. Case report and literature review]

BACKGROUND

Hepatic adenomas are uncommon epithelial tumours. They usually appear in women between 20 and 44 years old. They are commonly located in the right hepatic lobe and are typically solitary masses. Multiple adenomas can present in patients with prolonged use of oral contraceptive pills, glycogen storage diseases and hepatic adenomatosis.

CLINICAL CASE

A 35 year-old woman without any significant past medical history, with a chief complaint that started in December 2012 with oppressive, mild intensity abdominal pain located in right upper quadrant in the abdomen on deep palpation. With an abdominal ultrasound showing a mass of 91×82×65cm located in the right flank, isoechogenic with internal vascularity. Contrast computed tomography scan showing an ovoid tumour with circumscribed borders, with heterogenic intense reinforcement and displacement of adjacent structures with dimensions of 88×71×80cm. In laparotomy, excision of the tumour and cholecystectomy with the trans surgical findings of an 8cm tumour with a pedicle containing one artery and one vein coming from the hepatic free border with strong adhesions to the gallbladder. Pathologic diagnosis: Extracapsular hepatic adenoma.

CONCLUSIONS

Incidence of hepatic adenomas has increased in the last decades, in a parallel fashion with the introduction of oral contraceptive pills, showing association with glycogen storage diseases and to a lesser degree with diabetes and pregnancy. Diagnosis is clinical with the aid of imaging studies. Prognosis of hepatic adenomas is not well established, therefore, management depends on symptoms, size, number, location and certainty of diagnosis.

Management of hepatic adenomatosis

Hepatic adenomatosis (HeAs) is a rare clinical entity defined by the presence of 10 or more hepatic adenomas (HA) within the background of an otherwise normal liver parenchyma, in the absence of glycogen storage disease or anabolic steroid use. HA is a benign tumor associated with oral contraceptive use. Recent advances in pathogenesis and classification of HA have questioned the distinction between these two diseases. HA are currently classified into four different subtypes with genotypic and phenotypic correlation: HNF-1a inactivated HA, B-catenin activated HA, inflammatory HA, and undetermined subtype. The clinical presentation of HA depends on the lesion size and the subtype. MRI using hepatospecific contrast agents is helpful in diagnosing the most common subtypes. When diagnosis is uncertain, biopsy with immunohistochemistry is used to diagnose and classify the lesions. Management is governed by the molecular subtype and tumor size. Pregnancy is not routinely discouraged but management is individualized.

Hepatocellular adenoma with malignant transformation in male patients with non-cirrhotic livers

Introduction

Hepatocellular adenomas (HCAs), with a risk of malignant transformation into hepatocellular carcinoma (HCC), classically develop in young women who are taking oral contraceptives. It is now clear that HCAs may also occur in men. However, it is rarely reported that HCAs with malignant transformation occur in male patients with non-cirrhotic livers. This study aimed to characterize the malignancy of HCAs occurring in male patients.

Methods

All patients with HCAs with malignant transformation who underwent hepatectomy at the Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College between January 1, 1999 and December 31, 2011 were enrolled in the study. The clinical characteristics as well as radiologic and pathologic data were reviewed.

Results

HCAs with malignant transformation were observed in 5 male patients with non-cirrhotic livers, but not in female patients. The alpha-fetoprotein (AFP) levels were higher in patients with HCAs with malignant transformation than in patients with HCAs without malignant transformation. The diameters of the tumors with malignant transformation were larger than 5 cm in 3 cases and smaller than 5 cm in 2 cases. The 5 patients were all alive without recurrence by the end of the study period. The disease-free survival times of the 5 patients were 26, 48, 69, 69, and 92 months.

Conclusion

Our results indicate that resection would be advised even if the presumptive diagnosis is adenoma smaller than 5 cm in diameter, especially in male patients.

National trends in the use of surgery for benign hepatic tumors in the United States

BACKGROUND

The widespread use of diagnostic imaging has led to an increase in the incidence and diagnosis of benign liver tumors. The objective of this study was to define the overall use and temporal trends of operative procedures for benign liver tumors using a nationally representative cohort.

METHODS

All patients who underwent liver surgery for benign liver tumors between 2000 and 2011 were identified from the Nationwide Inpatient Sample database. Trends in annual volume of liver procedures were analyzed using the average annual percent change (AAPC) assessed by joinpoint analysis.

RESULTS

There were 2,489 open (94.5%) and 144 (5.5%) minimally invasive surgical (MIS) procedures. Partial hepatectomy accounted for 43.8% of all cases (n = 1,153). Surgery for patients with benign liver tumors increased from 156 in 2000 to 272 in 2011 (AAPC, 5.8%; 95% CI, 3.2-8.6%). There was decline in the relative use of open operative procedures from 98.1% in 2000 to 92.3% in 2011 (AAPC, -0.4%; 95% CI, -0.7 to -0.1%). In contrast, the proportion of MIS procedures increased from 1.9% in 2000 to 7.7% in 2011 (AAPC, 7.4%; 95% CI, 1.9-13.3%). The median duration of stay among all patients was 5 days (interquartile range, 4-7; 5 days [open] vs 3 days [MIS]; P < .001). Inpatient mortality was 0.6% (n = 15 [open] vs n = 0 [MIS]; P = .43) and did not change during the study period (P > .05).

CONCLUSION

Overall volume of surgical management of benign liver tumors has increased substantially over the past decade. There has been a relative shift away from open procedures toward MIS procedures.

Malignant transformation of hepatocellular adenoma

Hepatocellular adenomas carry a risk of malignant transformation. However, little is known about the rate of this risk, the predisposing factors, the histological and/or immunohistochemical markers and the precursor lesions. Even the pathogenesis of malignant transformation itself is poorly understood. This review details the current knowledge on the subject.

Liver adenomatosis: a rare indication for living donor liver transplantation

Liver adenomatosis (LA) is a rare benign disease of the liver with unclear pathogenesis, which is characterized by multiple hepatic adenomas. The management of LA remains controversial. Herein we have reported a case of LA treated by living donor liver transplantation (LDLT). A 48-year-old woman developed multiple liver adenomas. In view of the sizes and localizations of the lesions, the patient underwent right hepatic resection and segment II nodulectomy. Thirty-four months later, she developed recurrence of multiple hepatic adenomas and 2 nodules were highly suspect for hepatocellular carcinoma. Re-resection was not indicated due to the whole liver being involved with adenomas. The patient underwent LDLT. At 45 months thereafter she is alive and disease-free. In conclusion, LDLT is indicated in cases of nonresectability; it may offer optimal results in view of the absence of portal hypertension and the elimination of waiting list time.

ACG clinical guideline: the diagnosis and management of focal liver lesions

Focal liver lesions (FLL) have been a common reason for consultation faced by gastroenterologists and hepatologists. The increasing and widespread use of imaging studies has led to an increase in detection of incidental FLL. It is important to consider not only malignant liver lesions, but also benign solid and cystic liver lesions such as hemangioma, focal nodular hyperplasia, hepatocellular adenoma, and hepatic cysts, in the differential diagnosis. In this ACG practice guideline, the authors provide an evidence-based approach to the diagnosis and management of FLL.

Open and laparoscopic resection of hepatocellular adenoma: trends over 23 years at a specialist hepatobiliary unit

BACKGROUND

Hepatocellular adenoma (HCA) is a rare benign liver epithelial tumour that can require surgery. This retrospective study reports a 23-year experience of open and laparoscopic resections for HCA.

METHODS

Patients with a histological diagnosis of HCA were included in this analysis. Surgical resection was performed in all symptomatic patients and in those with lesions measuring >5 cm.

RESULTS

Between 1989 and 2012, 62 patients, 59 of whom were female, underwent surgery for HCA (26 by open surgery and 36 by laparoscopic surgery). Overall, 96.6% of female patients had a history of contraceptive use; 54.8% of patients presented with abdominal pain and 11.2% with haemorrhage; the remaining patients were asymptomatic. Patients who underwent laparoscopy had smaller lesions (mean ± standard deviation diameter: 68.3 ± 35.2 mm versus 91.9 ± 42.5 mm; P = 0.022). Operatively, laparoscopic and open liver resection did not differ except in the number of pedicle clamps, which was significantly lower in the laparoscopic group (27.8% versus 57.7% of patients; P = 0.008). Postoperative variables did not differ between the groups. Mortality was nil. Two surgical specimens were classified as HCA/borderline hepatocellular carcinoma. At the 3-year follow-up, all patients were alive with no recurrence of HCA.

CONCLUSIONS

Open and laparoscopic liver resections are both safe and feasible approaches for the surgical management of HCA. However, laparoscopic liver resections may be limited by lesion size and location and require advanced surgical skills.

Risk factors for bleeding in hepatocellular adenoma

BACKGROUND

Hepatocellular adenoma (HCA) is a benign hepatic lesion that may be complicated by bleeding, although the risk of bleeding is ill-defined. The aim of this study was to assess risk factors for bleeding in patients diagnosed with HCA.

METHODS

Patients with HCA were included prospectively from January 2008 to July 2012. Patient characteristics were noted. Patients underwent dynamic magnetic resonance imaging (MRI) and/or computed tomography (CT) at presentation and during follow-up. Lesion characteristics on (follow-up) imaging were noted, and bleeding was graded as intratumoral (grade I), intrahepatic (grade II) or extrahepatic (grade III). The standard of reference for diagnosis was histopathology, or dynamic MRI and/or CT findings. Possible risk factors were included if mentioned in literature (lesion size, body mass index), or based on clinical experience (lesion location, visible vessels on imaging).

RESULTS

A total of 45 patients (median age 39 (range 22-60) years; 44 women) with 195 lesions (median size 24 (10-250) mm) were evaluated. Bleeding occurred in 29 patients (64 per cent) and in 42 lesions (21.5 per cent) with a median size of 62 (10-160) mm. Size was a risk factor for bleeding (P < 0.001), with an increased number of bleeding events in lesions of 35 mm or more. Exophytic lesions (protruding from liver) had more bleeding (16 of 24, 67 per cent) than intrahepatic (9 of 82, 11 per cent) or subcapsular (17 of 89, 19 per cent) lesions (P < 0.001). Lesions in segments II and III had more bleeds than those in the right liver (11 of 32 versus 31 of 163; P = 0.049), as did lesions in which peripheral or central arteries were visualized on imaging (10 of 13 versus 32 of 182 lesions with no visible vascularization; P < 0.001).

CONCLUSION

Risk factors for bleeding of HCA include diameter of 35 mm or more, visualization of lesional arteries, location in the left lateral liver, and exophytic growth.

Hepatocellular adenomatosis: what should the term stand for!

In 1985, adenomatosis, a term coined to mean ten or more nodules, was considered as a specific entity different from hepatocellular adenoma (HCA) whether single or multiple. In the 2000s the term has lost its individuality. The great contribution of the classification was to clearly demonstrate that in all hepatocellular subtypes and in particular etiologies such as glycogenosis and male hormone administration, HCA could be solitary, multiple (<10) or multiple (>10: adenomatosis). Management of hepatocellular adenomatosis may not be different from solitary or multiple HCA. To keep its specificity in terms of management and prognosis compared to solitary or multiple HCA, it is necessary to indicate the number of nodules including the combination of three parameters: size, location and subtypes. When the classical armentarium to treat nodules is not possible or too risky, embolization or liver transplantation remains the only therapeutic options.

Diagnostic Approach to Hepatic Mass Lesions and Role of Immunohistochemistry

This review provides an overview of various hepatic mass lesions and a practical diagnostic approach, including most recent immunohistochemical stains used in clinical practice. A wide variety of benign and malignant lesions present as hepatic masses, and the differential diagnosis varies. In cirrhotic liver, the commonest malignant tumor is hepatocellular carcinoma (HCC), which needs to be differentiated from macroregenerative nodules, dysplastic nodules, and other tumors. The differential diagnosis of lesions in noncirrhotic liver in younger patients includes hepatic adenoma (HA), focal nodular hyperplasia (FNH), HCC, and other primary hepatic neoplasms and metastases. In older populations, metastases remain the most common mass lesions.

[Immunophenotypic classification of 3 cases of hepatocellular adenoma. Differential diagnosis with focal nodular hyperplasia]

Interest in adenomas has been renewed by the discovery of the molecular changes in these tumors. The latest World Health Organization publication on gastrointestinal tract tumors (2010) includes four types of hepatic adenomas, which are well characterized immunohistochemically, genotypically and phenotypically. In these tumors, medical history and morphological behavior play an important role in determining the risk of malignancy, mainly in adenomas with a b-catenin mutation. The presence of steatosis, inflammation, vascular changes linked to response to L-FABP, serum amyloid A, and glutamyl synthetase help to classify these tumors into four groups: hepatocellular adenomas with the HNF1A mutation (H-HCA), those with the b-catenin mutation (b-HCA), inflammatory HCA (IHCA), and HCA without markers. The absence of glypican 3 expression, HSP 70 and perivenular mapping of glutamyl synthetase helps to distinguish these tumors from well differentiated hepatocellular carcinoma. We describe the clinical, morphological and immunophenotypic features of three patients diagnosed with hepatic adenomas in a 2-year period.

Molecular pathogenesis of hepatic adenomas and its implications for surgical management

INTRODUCTION

Hepatic adenomas (HAs) are benign tumors of the liver, which can be solitary or multiple, and have a definite risk of malignant degeneration.

DISCUSSION

The pathogenesis and natural history of this disease entity were previously unknown. Recent research into the molecular pathogenesis of this condition has provided evidence for the malignant transformation of some of these adenomas. In the current article, we discuss the current evidence on the molecular biology underlying malignant transformation of hepatic adenomas and the implications for the surgical management of this disease.

Economic model of observation versus immediate resection of hepatic adenomas

BACKGROUND AND OBJECTIVES

For small asymptomatic hepatic adenomas (HA), available data are insufficient to establish the superiority of either observation or surgery. We sought to investigate the cost-effectiveness of two initial management strategies.

METHODS

We performed a comparative analysis of two theoretical cohorts of 100 patients with small (<5 cm), asymptomatic HA. Discounted cash flow (DCF) models compared the net present value (NPV) of both treatment options at year 10 under three distinct progression rate scenarios. A break-even (BE) analysis was used to determine the BE point at which the NPV for observation and immediate surgery intersect.

RESULTS

The NPV for immediate surgery was $1,733,955. The NPV for observation varied between $2,065,315-$2,745,631 for computed tomography (CT), $2,264,575-$2,929,541 for magnetic resonance imaging (MRI), and $802,837-$1,580,413 for ultrasound (US). The BE point was between 6 and 8 years for CT and 5-7 years for MRI. The BE point for US was not reached except in the highest progression rate scenario (12 years).

CONCLUSIONS

This study highlights the importance of the underlying progression rate and the cost of imaging when following patients with asymptomatic HA. Overall, US surveillance is the most cost-efficient approach to observing small asymptomatic HA. If cross-sectional imaging is utilized, then immediate surgery is the most cost-effective decision at 5-8 years.

A new long term hepatic complication in survivors of childhood haematological malignancy

Hepatic abnormalities have been documented in survivors of childhood malignancies and a spectrum of liver diseases has been described in this group The risk factors for liver disease include: hepatic surgery; radiotherapy to field including liver; total body irradiation (TBI); chemotherapy, multiple blood transfusions and use of hematopoietic cell transplantation. We report three cases of hepatic adenomatosis (HA) in young women who had been treated for haematological malignancy as children and had bone marrow transplant. These women were on estrogen and growth hormone replacement. They had mild abnormalities of liver function tests. The diagnosis of HA was made on liver imaging and confirmed by liver biopsy. We also propose a hypothesis for the pathogenesis of hepatic adenomatosis in these patients which vascular damage, estrogen replacement and growth hormone deficiency.

Reticulin loss in benign fatty liver: an important diagnostic pitfall when considering a diagnosis of hepatocellular carcinoma

Reticulin stains are commonly used in surgical pathology to assess mass lesions for the possibility of hepatocellular carcinoma. The loss of normal reticulin staining can help support a diagnosis of hepatocellular carcinoma, and this stain has proven to be particularly helpful on limited biopsies and fine-needle aspirates. However, an underappreciated diagnostic pitfall is that non-neoplastic liver tissue can also show reticulin loss when there is fatty change. To further characterize this important diagnostic pitfall, reticulin staining was studied in cases of nonalcoholic steatosis, nonalcoholic steatohepatitis, and hepatic adenomas with fatty change. A total of 112 cases with varying degrees of steatosis were collected from 4 academic centers, including 49 cases of steatosis, 49 cases of steatohepatitis, and 14 hepatic adenomas with fatty change. Steatosis was graded as mild (5% to 30% macrovesicular steatosis), moderate (31% to 60%), and marked (>60%). Reticulin stains were scored as the number of foci with diminished reticulin staining in 10 hpf. A focus of diminished reticulin was scored when the extent of reticulin loss was similar to that seen in hepatocellular carcinomas. In the total study set, 28 cases showed mild steatosis, 40 cases showed moderate steatosis, and 44 cases showed marked steatosis. Interestingly, increasing amounts of fat were associated with decreased reticulin staining. For mild steatosis, reticulin loss was rare, with the number of foci of reticulin loss per 10 hpf averaging 0.8 (range, 0 to 3); however, this increased for moderate steatosis, which showed a mean of 3.0 foci per 10 hpf (range, 0 to 5), and was most prominent with marked steatosis, which showed an average of 5.8 foci of reticulin loss per 10 hpf (range, 5 to 8). An almost identical pattern was seen in cases of nonalcoholic steatohepatitis. Overall, reticulin loss was not associated with the degree of inflammation or with the presence or absence of balloon cell change. Reticulin loss also did not correlate with fibrosis stage. In hepatic adenomas, reticulin loss was seen only in areas of fatty change, and decreased reticulin again paralleled the amount of steatosis, with more prominent reticulin loss in those cases with marked steatosis. In conclusion, reticulin loss that reaches levels seen in hepatocellular carcinoma can be seen focally in benign liver tissues with fatty change. Overall, loss of reticulin is more common and more extensive with marked fatty change and does not seem to be linked to inflammation or fibrosis stage. Loss of reticulin can also be seen in hepatic adenomas with fatty change. Increased awareness of this important diagnostic pitfall will help prevent overcalling of reticulin loss when evaluating biopsies and resections of hepatic neoplasms with fatty change.

[Middle-aged female presenting with headache, blurred vision and skin rash]

BACKGROUND

Autoimmune hyperlipidemia (AIH) is a rare cause of secondary hyperlipidemia. A few cases of AIH have been reported in multiple myeloma.

MATERIAL AND METHODS

A female in her fifties was referred to the outpatient clinic presenting with headache, blurred vision and skin rash. Physical examination with subsequent laboratory and histological examinations revealed severe hyperlipidemia secondary to secretory multiple myeloma with monoclonal IgG kappa protein and erythrocytosis secondary to a erythropoietin secreting adenoma in the liver.

RESULTS AND INTERPRETATION

Treatment for multiple myeloma (induction treatment and autologous hematological stem cell transplantation) gained partial remission and was associated with normalization of serum lipids. There was no need for further medical treatment of the hyperlipidemia. Three years after the initial treatment, serum concentrations of triglycerides and total cholesterol increased in parallel with monoclonal IgG kappa protein. Total cholesterol and triglycerides decreased and remained within the reference ranges after retreatment with a second autologous stem cell transplantation. Surgical removal of the hepatic adenoma caused normalisation of the erythropoietin concentration and resolution of the erythrocytosis. The present case reports two rare complications (AIH and erythrocytosis) to multiple myeloma and hepatic adenoma, with regression of complaints and normalisation of laboratory tests after adequate treatment of underlying diseases.

Evaluation of liver lesions

The differential diagnosis of a liver mass is large and requires understanding of the clinical and imaging features of liver lesions. A detailed history, physical examination, hepatic biochemical tests, and imaging studies are all essential in making the diagnosis. Decisions regarding specific imaging modalities for diagnoses, the use of liver biopsy, therapeutic options, and appropriate follow-up are all determined by the presentation of the lesion and associated patient characteristics.

Can a decision-making model be justified in the management of hepatocellular adenoma?

During recent years, there was a great development in the area of hepatocellular adenomas (HCA), especially regarding the pathological subtype classification, radiological imaging and management during pregnancy. This review discusses the current knowledge about diagnosis and treatment modalities of HCA and proposes a decision-making model for HCA. A Medline search of studies relevant to epidemiology, histopathology, complications, imaging and management of HCA lesions was undertaken. References from identified articles were hand-searched for further relevant articles.

Contrast-enhanced ultrasound for the diagnosis of hepatic adenoma

Nine hepatic adenomas (HA) diagnosed by contrast-enhanced ultrasound (CEUS) among 123 liver lesions (89 patients) were evaluated retrospectively; five were confirmed through pathological diagnosis. Time-intensity curves (TIC), contrast medium arriving time (AT), peak time (PT) and retrogression time (RT) for HA were compared with 30 hepatocellular carcinomas (HCC) and six focal nodular hyperplasias (FNH). Significant differences existed between HA and poorly-differentiated HCC in AT, PT and RT, and between HA and well-differentiated HCC in AT. Differential diagnosis between HA and FNH was determined only through their different perfusion and arterial morphological features: HA showed typical perfusion characteristic of 'fast-in, slow-out', with a centripetal or mixed-filling pattern in the arterial phase, while FNH showed a centrifugal filling pattern. In conclusion, CEUS was helpful for identifying HA but it may be relatively difficult to distinguish between HA and some well-differentiated HCC or FNH.

Bland embolization in the treatment of hepatic adenomas: preliminary experience

The study presents preliminary, retrospective experience with bland embolization for hepatic adenomas (HAs) with the use of tris-acryl gelatin microspheres. Eight patients underwent bland embolization for biopsy-proven HAs. A biopsy specimen was taken from only one lesion when multiple lesions were present. Seventeen embolizations were performed for abdominal pain, active bleeding, or prophylaxis against bleeding. Five patients underwent multiple procedures. Technical success rate was 100%. Median follow-up was 24 months (range, 10-40 mo). No growth was observed at follow-up in any treated lesion, and many lesions (13 of 16) regressed. Bland embolization may be safely used for treatment of abdominal pain and bleeding from HAs.

Laparoscopic liver resection for hepatocellular adenoma

AIM

To investigate the role of laparoscopy in the surgical management of hepatocellular adenoma (HA).

METHODS

We reviewed a prospectively collected database of consecutive patients undergoing laparoscopic liver resection for HA.

RESULTS

Thirteen patients underwent fifteen pure laparoscopic liver resections for HA (male/female: 3/10; median age 42 years, range 22-72 years). Two patients with liver adenomatosis required two different laparoscopic operations for ruptured adenomas. Indications for surgery were: symptoms in 12 cases, need to rule out malignancy in 2 cases and preoperative diagnosis of large HA in one case. Symptoms were related to bleeding in 10 cases, sepsis due to liver abscess following embolization of HA in one case and mass effect in one case (shoulder tip pain). Five cases with ruptured bleeding adenoma required emergency admission and treatment with selective arterial embolization. Laparoscopic liver resection was then semi-electively performed. Eight patients (62%) required major hepatectomy [right hepatectomy (n = 5), left hepatectomy (n = 3)]. No conversion to open surgery occurred. The median operative time for pure laparoscopic procedures was 270 min (range 135-360 min). The median size of the excised lesions was 85 mm (range 25-180 mm). One patient with adenomatosis developed postoperative bleeding requiring embolization. Mortality was nil. The median hospital stay was 4 d (range 1-18 d) with a median high dependency unit stay of 1 d (range 0-7 d).

CONCLUSION

The laparoscopic approach represents a safe option for the management of HA in a semi-elective setting and when major hepatectomy is required.

Biologic and clinical features of benign solid and cystic lesions of the liver

The widespread use of imaging analyses, either routinely or to evaluate symptomatic patients, has increased the detection of liver lesions (tumors and cysts) in otherwise healthy individuals. Although some of these incidentally discovered masses are malignant, most are benign and must be included in the differential diagnosis. The management of benign hepatic tumors ranges from conservative to aggressive, depending on the nature of the lesions. New imaging modalities, increased experience of radiologists, improved definition of radiologic characteristics, and a better understanding of the clinical features of these lesions have increased the accuracy of diagnoses and reduced the need for invasive diagnostic tests. These advances have led to constant adjustments in management approaches to benign hepatic lesions. We review the biologic and clinical features of some common hepatic lesions, to guide diagnosis and management strategies.

Systematic review of hepatocellular adenoma in China and other regions

Hepatocellular adenoma (HCA) is a benign liver neoplasm with a risk of spontaneous bleeding and malignant transformation. The aim of this review article is to review all the case reports and case series of patients with HCA from 1998 to 2008 in China and other parts of the world in order to compare clinical presentation, surgical management and outcomes. A search for all reports of HCA in the world literature from 1998 to 2008 was performed. A total of 356 patients were identified, including 191 patients from China, 104 from Europe, 46 from North America, and 15 from South-East Asia. A female predominance was not observed in Chinese patients in contrast to the other regions. Acute/chronic abdominal pain was the main clinical presentation in all regions. Twenty patients were diagnosed with coexistent hepatocellular carcinoma (HCC), and hepatitis B virus infection (HBV) was found among six of them. The management of HCA consisted of resection in most cases. The clinical presentation of HCA in China differed from other parts of the world regarding male predominance and a higher incidence of coexistent HCC in China. This might be the result of the birth control policy in China, limited oral contraceptive use, and the higher incidence of HBV.

Malignant transformation of hepatocellular adenomas into hepatocellular carcinomas: a systematic review including more than 1600 adenoma cases

BACKGROUND

Malignant transformation of hepatocellular adenomas (HCAs) into hepatocellular carcinomas (HCCs) has been reported repeatedly and is considered to be one of the main reasons for surgical treatment. However, its actual risk is currently unknown.

OBJECTIVE

To provide an estimation of the frequency of malignant transformation of HCAs and to discuss its clinical implications.

METHODS

A systematic literature search was conducted using the following databases: The Cochrane Hepatobiliary Group Controlled Trials Register, The Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, MEDLINE and EMBASE.

RESULTS

One hundred and fifty-seven relevant series and 17 case reports (a total of 1635 HCAs) were retrieved, reporting an overall frequency of malignant transformation of 4.2%. Only three cases (4.4%) of malignant alteration were reported in a tumour smaller than 5 cm in diameter.

DISCUSSION

Malignant transformation of HCAs into HCCs remains a rare phenomenon with a reported frequency of 4.2%. A better selection of exactly those patients presenting with an HCA with an amplified risk of malignant degeneration is advocated in order to reduce the number of liver resections and thus reducing the operative risk for these predominantly young patients. The Bordeaux adenoma tumour markers are a promising method of identifying these high-risk adenomas.

Differentiation of hepatocellular adenoma and focal nodular hyperplasia using 18F-fluorocholine PET/CT

The aim of this pilot study was to evaluate the use of PET/CT with ¹⁸F-fluorocholine in the differentiation of hepatocellular adenoma (HCA) from focal nodular hyperplasia (FNH). Patients with liver lesions larger than 2 cm suspicious for HCA or FNH were prospectively included. All patients underwent PET/CT with ¹⁸F-fluorocholine and histopathological diagnosis was obtained by either liver biopsy or surgery. The ratios between the maximum standardized uptake value (SUV) of the lesion and the mean SUV of normal liver parenchyma were calculated and a receiver operating characteristic (ROC) curve analysis was performed. Ten patients with FNH and 11 with HCA were included. The mean SUV ratio was 1.68±0.29 (±SD) for FNH and 0.88±0.18 for HCA (p<0.001). An SUV ratio cut-off value between 1.12 and 1.22 differentiated patients with FNH from those with HCA with 100% sensitivity and 100% specificity. This pilot study showed that PET/CT with ¹⁸F-fluorocholine can differentiate HCA from FNH.

Non-viral causes of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common primary liver malignancy and represents an international public health concern as one of the most deadly cancers worldwide. The main etiology of HCC is chronic infection with hepatitis B and hepatitis C viruses. However, there are other important factors that contribute to the international burden of HCC. Among these are obesity, diabetes, non-alcoholic steatohepatitis and dietary exposures. Emerging evidence suggests that the etiology of many cases of HCC is in fact multifactorial, encompassing infectious etiologies, comorbid conditions and environmental exposures. Clarification of relevant non-viral causes of HCC will aid in preventative efforts to curb the rising incidence of this disease.

Chromosomal abnormalities determined by comparative genomic hybridization are helpful in the diagnosis of atypical hepatocellular neoplasms

AIMS

To explore the utility of cytogenetic abnormalities in the distinction of hepatic adenoma (HA) and well-differentiated hepatocellular carcinoma (HCC).

METHODS AND RESULTS

Array-based comparative genomic hybridization (CGH) was used to determine chromosomal abnormalities in 39 hepatocellular neoplasms: 12 HA, 15 atypical hepatocellular neoplasms (AHN) and 12 well-differentiated HCC. The designation of AHN was used in two situations: (i) adenoma-like neoplasms (n = 8) in male patients (any age) and women >50 years and <15 years old; (ii) adenoma-like neoplasms with focal atypical features (n = 7). CGH abnormalities were seen in none of the HAs (0/12), eight (53%) AHNs and 11 (92%) HCCs. The number and nature of abnormalities in AHN was similar to HCC with gains in 1q, 8q and 7q being the most common. Although follow-up information was limited, recurrence and/or metastasis were observed in three AHNs (two with abnormal, one with normal CGH).

CONCLUSIONS

Adenoma-like neoplasms with focal atypical morphological features or unusual clinical settings such as male gender or women outside the 15-50 year age group can show chromosomal abnormalities similar to well-differentiated HCC. Even though these tumours morphologically mimic adenoma, they can recur and metastasize. Determination of chromosomal abnormalities can be useful in the diagnosis of AHN.

Hepatocellular adenoma in advanced-stage fatty liver disease

Hepatocellular adenomas are defined as benign hepatocellular neoplasms occurring in otherwise near normal liver and adenomatosis as 10 or more such lesions. We present a case of a 45-year-old man with radiological adenomatosis, histologically confirmed with resection of one lesion, arising within advanced-stage nonalcoholic fatty liver disease (nearly cirrhotic). Hepatocellular adenomas have recently been divided into four categories and the lesion in the present case had morphologic and immunohistochemical features of an inflammatory hepatocellular adenoma. These findings demonstrate that, in contrast to the current dogma, nodules within advanced-stage liver disease may rarely be best classified as adenomas. This should be considered in the radiological differential diagnosis when assessing a patient's suitability for transplantation.

Diagnosis and treatment of benign focal liver lesions

BACKGROUND

With the routine use of improved imaging modalities, more benign liver lesions are detected nowadays. An accurate characterization of these incidental lesions may be a challenge, and frequently a biopsy or even unnecessary surgery is being performed. However, these interventions are not always to the benefit of the patient.

METHODS

A Medline search of studies relevant to imaging diagnosis and management of the most common, benign, solid and non-solid liver lesions was undertaken. References from identified articles were handsearched for further relevant articles. The authors' own experiences with benign liver lesions were also taken into account.

RESULTS

Although atypical imaging features are the exception rather than the rule, it is sometimes difficult to differentiate between benign and malignant lesions, and knowledge of their imaging features is essential if unnecessary work-up is to be avoided. The use of tissue-specific contrast media, which has clearly improved the accuracy of highly advanced radiological techniques, may be helpful during differential diagnosis. Once having established an accurate diagnosis, surgery is rarely indicated for a benign liver lesion because of its asymptomatic nature.

CONCLUSION

Knowledge of imaging features and a clear management strategy during diagnostic work-up, emphasizing the indications for surgery, will minimize the number of patients who have to undergo biopsy or unnecessary surgery.

[Hepatocellular carcinoma in the non-cirrhotic liver]

Of hepatocellular carcinomas (HCC), 15-20% occur in the non-cirrhotic liver. All factors which cause HCC when liver cirrhosis (LC) is present, can also lead to HCC without LC. On the basis of the relative frequency, HCC can be roughly differentiated into 3 groups: 1) HCC, rarely occurring without cirrhosis (e.g. virus hepatitis, alcohol abuse). 2) HCC, frequently occurring without LC (alpha1-antitrypsin deficiency, hemochromatosis, non-alcoholic fatty liver disease). 3) HCC, consistently occurring without LC (glycogen storage disease type 1, consumption of oral contraceptives/anabolic steroids). In groups 1 and 2 the level of hepatocellular toxicity necessary to reach LC is not yet achieved but the carcinogenic effect is already strong enough to induce HCC, possibly owing to the influence of additional carcinogens or host factors. In group 3, the carcinogenic effect is mediated by a long-standing alteration of the hepatocellular metabolism that is of low toxic effect and does not lead to cell death, but is nevertheless carcinogenic. In these cases, the initial formation of hepatocellular adenomas that subsequently transform into HCC is a common finding (adenoma-carcinoma sequence).

Approach to a liver mass

Incidentally discovered liver masses are becoming more common with the increasing application and power of imaging techniques for the evaluation of abdominal conditions. Although such masses are often benign, conclusive diagnoses must be established in order to provide appropriate patient care. Various imaging modalities can be utilized to accurately diagnose such masses without resort to more invasive diagnostic measures.