Hepatocellular adenoma in men: A nationwide assessment of pathology and correlation with clinical course

Hepatic adenomas in males: Is molecular characterization helpful in guiding its management?

BACKGROUND AND AIMS

Hepatocellular adenomas (HCAs) in males are very rare. We performed detailed clinicopathologic, immunohistochemical and molecular characterization of HCAs in males, to understand their pathogenesis and malignant potential.

METHODS

Seven cases of HCA in males formed our study cohort. The histologic slides, clinical and follow-up information were reviewed and immunohistochemical stains were performed. DNA was extracted and targeted sequencing was performed using Ion Torrent chemistry. Filtered variants were annotated to identify pathogenic mutations.

RESULTS

Six (86 %) patients were morbidly obese. All showed at least focal cytologic atypia. Three lesions were markedly steatotic and 2 were hemorrhagic. One lesion showed focal reticulin loss, diffuse glutamine synthetase (GS) positivity and beta-catenin (β-catenin) nuclear staining, suggestive of atypical hepatocellular neoplasm. Three (42.8 %) cases were inflammatory-type, showing diffuse serum amyloid-associated protein/C-reactive protein. One other inflammatory-type HCA showed peripheral accentuation with GS and another non-inflammatory HCA showed patchy staining with GS; both revealed CTNBB1 mutations but no β-catenin nuclear staining. None showed TP53, TERT promotor mutations, or significant copy number alterations.

CONCLUSION

A significant proportion of HCAs in males occurred in obese patients and were inflammatory-type. While some are beta-catenin mutated and need to be resected, a subset of HCAs in males appears to be low-risk by molecular features and may be treated conservatively.

Lesions hyper- to isointense to surrounding liver in the hepatobiliary phase of gadoxetic acid-enhanced MRI

OBJECTIVES

Hyper- or isointensity in the hepatobiliary phase (HBP) of gadoxetic acid-enhanced MRI has high specificity for focal nodular hyperplasia (FNH) but may be present in hepatocellular adenoma and carcinoma (HCA/HCC). This study aimed to identify imaging characteristics differentiating FNH and HCA/HCC.

MATERIALS AND METHODS

This multicenter retrospective cohort study included patients with pathology-proven FNH or HCA/HCC, hyper-/isointense in the HBP of gadoxetic acid-enhanced MRI between 2010 and 2020. Diagnostic performance of imaging characteristics for the differentiation between FNH and HCA/HCC were reported. Univariable analyses, multivariable logistic regression analyses, and classification and regression tree (CART) analyses were conducted. Sensitivity analyses evaluated imaging characteristics of B-catenin-activated HCA.

RESULTS

In total, 124 patients (mean age 40 years, standard deviation 10 years, 108 female) with 128 hyper-/isointense lesions were included. Pathology diagnoses were FNH and HCA/HCC in 64 lesions (50%) and HCA/HCC in 64 lesions (50%). Imaging characteristics observed exclusively in HCA/HCC were raster and atoll fingerprint patterns in the HBP, sinusoidal dilatation on T2-w, hemosiderin, T1-w in-phase hyperintensity, venous washout, and nodule-in-nodule partification in the HBP and T2-w. Multivariable logistic regression and CART additionally found a T2-w scar indicating FNH, less than 50% fat, and a spherical contour indicating HCA/HCC. In our selected cohort, 14/48 (29%) of HCA were B-catenin activated, most (13/14) showed extensive hyper-/isointensity, and some had a T2-w scar (4/14, 29%).

CONCLUSION

If the aforementioned characteristics typical for HCA/HCC are encountered in lesions extensively hyper- to isointense, further investigation may be warranted to exclude B-catenin-activated HCA.

CLINICAL RELEVANCE

Hyper- or isointensity in the HBP of gadoxetic acid-enhanced MRI is specific for FNH, but HCA/HCC can also exhibit this feature. Therefore, we described imaging patterns to differentiate these entities.

KEY POINTS

FNH and HCA/HCC have similar HBP intensities but have different malignant potentials. Six imaging patterns exclusive to HCA/HCC were identified in this lesion population. These features in liver lesions hyper- to isointense in the HBP warrant further evaluation.

ACG Clinical Guideline: Focal Liver Lesions

Focal liver lesions (FLLs) have become an increasingly common finding on abdominal imaging, especially asymptomatic and incidental liver lesions. Gastroenterologists and hepatologists often see these patients in consultation and make recommendations for management of multiple types of liver lesions, including hepatocellular adenoma, focal nodular hyperplasia, hemangioma, and hepatic cystic lesions including polycystic liver disease. Malignancy is important to consider in the differential diagnosis of FLLs, and healthcare providers must be familiar with the diagnosis and management of FLLs. This American College of Gastroenterology practice guideline uses the best evidence available to make diagnosis and management recommendations for the most common FLLs.

Association Between Gadoxetic Acid-Enhanced Magnetic Resonance Imaging, Organic Anion Transporters, and Farnesoid X Receptor in Benign Focal Liver Lesions

The organic anion uptake and efflux transporters [organic anion-transporting polypeptide (OATP)1B1, OATP1B3 and multidrug resistance-associated protein (MRP)2 and MRP3] that mediate the transport of the hepatobiliary-specific contrast agent gadoxetate (Gd-EOB-DTPA) are direct or indirect targets of the farnesoid X receptor (FXR), a key regulator of bile acid and lipid homeostasis. In benign liver tumors, FXR expression and activation is not yet characterized. We investigated the expression and activation of FXR and its targets in hepatocellular adenoma (HCA) and focal nodular hyperplasia (FNH) and their correlation with Gd-EOB-DTPA-enhanced magnetic resonance imaging (MRI). Gd-EOB-DTPA MRI patterns were assessed by an expert radiologist. The intensity of the lesions on the hepatobiliary phase was correlated to mRNA expression levels of OATP1B1, OATP1B3, MRP2, MRP3, FXR, and small heterodimer partner (SHP) in fresh surgical specimens of patients with FNH or HCA subtypes. Normal and tumor sample pairs of 43 HCA and 14 FNH were included. All FNH (14/14) were hyperintense. Of the 34 HCA with available Gd-EOB-DTPA-enhanced MRI, 6 were hyperintense and 28 HCA were hypointense. OATP1B3 was downregulated in the hypointense tumors compared with normal surrounding liver tissue (2.77±3.59 vs. 12.9±15.6, P < 0.001). A significant positive correlation between FXR expression and activation and OATP1B3 expression level was found in the HCA cohort. SHP showed a trend toward downregulation in hypointense HCA. In conclusion, this study suggests that the MRI relative signal in HCA may reflect expression level and/or activity of SHP and FXR. Moreover, our data confirms the pivotal role of OATP1B3 in Gd-EOB-DTPA uptake in HCA. SIGNIFICANCE STATEMENT: FXR represents a valuable target for the treatment of liver disease and metabolic syndrome. Currently, two molecules, ursodeoxycholate and obeticholate, are approved for the treatment of primary biliary cirrhosis and cholestasis, with several compounds in clinical trials for the treatment of metabolic dysfunction-associated fatty liver disease. Because FXR expression and activation is associated with gadoxetate accumulation in HCA, an atypical gadoxetate-enhanced MRI pattern might arise in patients under FXR-targeted therapy, thereby complicating the differential diagnosis.

Hepatocellular Carcinoma in Non-Fibrotic Liver: A Narrative Review

Hepatocellular carcinoma (HCC) in a non-fibrotic liver (F0) is considered to be rare, and there is a marked paucity of studies in the literature on this HCC type. A review of the literature shows some important clinical and tumor characteristics: (a) it occurs mainly in young female and elder male patients; (b) clinically, under normal hepatic function, alpha-fetoprotein level is often normal, and there are no risk factors; (c) associated with metabolic disease; (d) macroscopically, single large lesions are noted; and (e) microscopically, the lesions are well-differentiated and encapsulated. Radiological imaging results are straightforward, showing arterial hyperenhancement and later wash-out. The combined use of B-mode and contrast-enhanced (CE) ultrasound (US) is the most reliable and cost-effective diagnostic method. Few peri-and post-operative complications are noted and 5-year survival is not inferior to patients with HCC on fibrosis liver despite the lesion's large size. Most clinicians believe that HCC is unlikely to occur if patients have no symptoms and normal hepatic function. Although detailed clinical data are very limited, we expect that this review will help to improve the clinical management of HCC in non-fibrotic livers.

Estrobolome and Hepatocellular Adenomas-Connecting the Dots of the Gut Microbial β-Glucuronidase Pathway as a Metabolic Link

Hepatocellular adenomas are benign endothelial tumors of the liver, mostly associated with female individual users of estrogen-containing medications. However, the precise factors underlying the selective development of hepatic adenomas in certain females remain elusive. Additionally, the conventional profile of individuals prone to hepatic adenoma is changing. Notably, male patients exhibit a higher risk of malignant progression of hepatocellular adenomas, and there are instances where hepatic adenomas have no identifiable cause. In this paper, we theorize the role of the human gastrointestinal microbiota, specifically, of bacterial species producing β-glucuronidase enzymes, in the development of hepatic adenomas through the estrogen recycling pathway. Furthermore, we aim to address some of the existing gaps in our knowledge of pathophysiological pathways which are not yet subject to research or need to be studied further. As microbial β-glucuronidases proteins recycle estrogen and facilitate the conversion of inactive estrogen into its active form, this process results in elevated levels of unbound plasmatic estrogen, leading to extended exposure to estrogen. We suggest that an imbalance in the estrobolome could contribute to sex hormone disease evolution and, consequently, to the advancement of hepatocellular adenomas, which are estrogen related.

Sex differences in chronic liver disease and benign liver lesions

The epidemiology, natural history, and therapeutic responses of chronic liver diseases and liver lesions often vary by sex. In this review, we summarize available clinical and translational data on these aspects of the most common liver conditions encountered in clinical practice, including the potential contributions of sex hormones to the underlying pathophysiology of observed differences. We also highlight areas of notable knowledge gaps and discuss sex disparities in access to liver transplant and potential strategies to address these barriers. Given established sex differences in immune response, drug metabolism, and response to liver-related therapies, emerging clinical trials and epidemiological studies should prioritize dedicated analyses by sex to inform sex-specific approaches to liver-related care.

Clinicopathologic characterization of hepatocellular adenomas in men: a multicenter experience

Hepatocellular adenomas (HCAs) are benign liver neoplasms which most commonly present in women in their reproductive age. In men, they are rare and have a higher risk of malignant transformation to hepatocellular carcinoma (HCC). Here we present our multicenter experience with HCA in men in the United States. A total of 27 HCA cases were included, with a mean age of presentation of 37 years (range, 9-69 years) and a mean size of 6.8 cm (range, 0.9-18.5 cm). Based on the 2019 World Health Organization classification, the most common subtype identified was inflammatory HCA (IHCA; 10 cases, 37.0%) followed by unclassified HCA (UHCA; 7 cases, 25.9%), HNF1A-inactivated HCA (H-HCA; 6 cases, 22.2%), β-catenin-activated IHCA (b-IHCA; 3 cases, 11.1%), and β-catenin-activated HCA (b-HCA; 1 case, 3.7%). Six additional cases diagnosed as hepatocellular neoplasm of uncertain malignant potential (HUMP) were also included in the study. These cases presented in a mean age of 46 years (range, 17-64 years) and a size of 10.8 cm (range, 4.2-16.5 cm). We evaluated the significance of androgen receptor (AR) expression by immunohistochemistry (IHC); of the 16 cases with materials available, 8 were considered positive using the Allred score system (2 IHCA, 2 H-HCA, 1 UHCA, and 3 HUMP). Of the total cases, 12 were diagnosed on biopsies, for which follow-up information is available for 7, and none of them show evidence of malignant transformation. Of the 21 resection cases, a concomitant well-differentiated HCC within the same lesion was identified in 5 cases (23.8%), which were diagnosed as HCA (n = 4) or HUMP (n = 1). Overall, 15% of cases in our entire cohort of HCA and HUMP showed concomitant HCC, while none of the 7 biopsy cases showed any malignant transformation on follow-up (range, 22-160 months; mean, 61.8 months).

A Case of a Beta-Catenin-Activated Hepatic Adenoma in a Male Patient With Familial Adenomatous Polyposis

Hepatocellular adenoma is a benign liver tumor often diagnosed incidentally in women of reproductive age who are taking oral contraceptives. In this study, we present a unique case of an 18-year-old man with known familial adenomatous polyposis who presented with sepsis in the setting of a recent total proctocolectomy and was incidentally found to have multiple large hepatic lesions. A biopsy of a liver lesion confirmed the diagnosis of a beta-catenin-activated hepatic adenoma. To the best of our knowledge, this is the first known case of beta-catenin-activated hepatic adenoma in a patient with a known familial adenomatous polyposis mutation. Beta-catenin is one of the many subtypes of hepatocellular adenomas, which carries a high risk of malignant transformation.

Variation in the management of benign liver tumors: A European survey and case vignette study

BACKGROUND

Management of focal nodular hyperplasia (FNH) and hepatocellular adenoma (HCA), is multidisciplinary and subject to practice variation. We aimed to evaluate variation in clinical management of FNH and HCA in Europe.

METHODS

We distributed an online survey (November 2021-March 2022) among 294 European experts. The survey included questions on local practice and included eight clinical vignettes. The clinical vignettes focused on FNH or HCA management in the setting of sex, lifestyle modification, and pregnancy.

RESULTS

The response rate was 32% and respondents included surgeons (38%), gastroenterologists/hepatologists (25%), radiologists (32%), and pathologists (1.6%) from ten European countries. We observed practice variation with regard to lifestyle modification and imaging follow-up in patients with FNH, and with regard to the management of HCA >5 cm before and during pregnancy. Finally, the management of HCA >5 cm after lifestyle modification deviated from EASL guideline recommendations.

CONCLUSION

Our survey illustrates variability in FNH and HCA management in Europe. Several areas were identified for future research and guideline recommendations, including FNH follow-up and the management of HCA >5 cm. We propose the organization of Delphi consensus meetings to prioritize areas of research and update current guidelines to optimize management for all patients with benign liver tumors.

A nationwide assessment of hepatocellular adenoma resection: Indications and pathological discordance

Hepatocellular adenomas (HCAs) are benign liver tumors associated with bleeding or malignant transformation. Data on the indication for surgery are scarce. We analyzed indications and outcome of patients operated for HCAs < 50 mm compared to HCAs ≥ 50 mm. Changes in final postoperative diagnosis were assessed. We performed a retrospective study that included patients who underwent resection for (suspected) HCAs in the Netherlands from 2014 to 2019. Indication for resection was analyzed and stratified for small (<50 mm) and large (≥50 mm) tumors. Logistic regression analysis was performed on factors influencing change in tumor diagnosis. Out of 222 patients who underwent surgery, 44 (20%) patients had a tumor <50 mm. Median age was 46 (interquartile range [IQR], 33-56) years in patients with small tumors and 37 (IQR, 31-46) years in patients with large tumors ( p  = 0.016). Patients with small tumors were more frequently men (21% vs. 5%, p  = 0.002). Main indications for resection in patients with small tumors were suspicion of (pre)malignancy (55%), (previous) bleeding (14%), and male sex (11%). Patients with large tumors received operations because of tumor size >50 mm (52%), suspicion of (pre)malignancy (28%), and (previous) bleeding (5.1%). No difference was observed in HCA-subtype distribution between small and large tumors. Ninety-six (43%) patients had a postoperative change in diagnosis. Independent risk factors for change in diagnosis were tumor size <50 mm (adjusted odds ratio [aOR], 3.4; p  < 0.01), male sex (aOR, 3.7; p  = 0.03), and lack of hepatobiliary contrast-enhanced magnetic resonance imaging (CE-MRI) (aOR, 1.8; p  = 0.04). Resection for small (suspected) HCAs was mainly indicated by suspicion of (pre)malignancy, whereas for large (suspected) HCAs, tumor size was the most prevalent indication. Male sex, tumor size <50 mm, and lack of hepatobiliary CE-MRI were independent risk factors for postoperative change in tumor diagnosis.

Benign liver lesions 2022: Guideline for clinical practice of Associazione Italiana Studio del Fegato (AISF), Società Italiana di Radiologia Medica e Interventistica (SIRM), Società Italiana di Chirurgia (SIC), Società Italiana di Ultrasonologia in Medicina e Biologia (SIUMB), Associazione Italiana di Chirurgia Epatobilio-Pancreatica (AICEP), Società Italiana Trapianti d'Organo (SITO), Società Italiana di Anatomia Patologica e Citologia Diagnostica (SIAPEC-IAP) - Part II - Solid lesions

Benign liver lesions are increasingly diagnosed in daily clinical practice due to the growing use of imaging techniques for the study of the abdomen in patients who have non-specific symptoms and do not have an increased risk of hepatic malignancy. They include simple or parasitic hepatic cysts and solid benign tumors which differ widely in terms of prevalence, clinical relevance, symptoms and natural history and often lead to significant clinical problems relating to diagnosis and clinical management. Following the need to have updated guidelines on the management of benign focal liver lesions, the Scientific Societies mainly involved in their management have promoted the drafting of a new dedicated document. This document was drawn up according to the present Italian rules and methodologies necessary to produce clinical, diagnostic, and therapeutic guidelines based on evidence. Here we present the second part of the guideline, concerning the diagnosis and clinical management of hemangioma, focal nodular hyperplasia, and hepatocellular adenoma.

Benign liver tumours: understanding molecular physiology to adapt clinical management

Improvements in understanding the pathophysiology of the different benign liver nodules have refined their nosological classification. New criteria have been identified using imaging, histology and molecular analyses for a precise diagnosis of these tumours. Improvement in the classification of liver tumours provides a more accurate prediction of disease progression and has modified patient management. Haemangioma and focal nodular hyperplasia, the most common benign liver tumours that develop in the absence of chronic liver disease, are usually easy to diagnose on imaging and do not require specific treatment. However, hepatocellular adenomas and cirrhotic macronodules can be difficult to discriminate from hepatocellular carcinoma. The molecular subtyping of hepatocellular adenomas in five major subgroups defined by HNF1A inactivation, β-catenin mutation in exon 3 or exon 7/8, and activation of inflammatory or Hedgehog pathways helps to identify the tumours at risk of malignant transformation or bleeding. New clinical, biological and molecular tools have gradually been included in diagnostic and treatment algorithms to classify benign liver tumours and improve patient management. This Review aims to explain the main pathogenic mechanisms of benign liver tumours and how this knowledge could influence clinical practice.

Scoping review of clinical practice guidelines on the management of benign liver tumours

OBJECTIVE

Benign liver tumours (BLT) are increasingly diagnosed as incidentalomas. Clinical implications and management vary across and within the different types of BLT. High-quality clinical practice guidelines are needed, because of the many nuances in tumour types, diagnostic modalities, and conservative and invasive management strategies. Yet, available observational evidence is subject to interpretation which may lead to practice variation. Therefore, we aimed to systematically search for available clinical practice guidelines on BLT, to critically appraise them, and to compare management recommendations.

DESIGN

A scoping review was performed within MEDLINE, EMBASE, and Web of Science. All BLT guidelines published in peer-reviewed, and English language journals were eligible for inclusion. Clinical practice guidelines on BLT were analysed, compared, and critically appraised using the Appraisal of Guidelines, Research and Evaluation (AGREE II) checklist regarding hepatic haemangioma, focal nodular hyperplasia (FNH), and hepatocellular adenoma (HCA). Preferred Reporting Items for Systematic Reviews and Meta-Analyses recommendations (PRISMA) for scoping reviews were adhered to.

RESULTS

The literature search yielded unique 367 papers, 348 were excluded after screening of title/abstract, and 16 after full-text screening. Three guidelines were included: the American College of Gastroenterology (ACG; 2014), Brazilian Society of Hepatology (SBH; 2015), and European Association for the Study of the Liver (EASL; 2016). There was no uniformity in the assessment methods for grading and gravity of recommendations between guidelines. Among observed differences were: (1) indications for biopsy in all three tumours; (2) advices on contraceptive pills and follow-up in FNH and HCA; (3) use of an individualised approach to HCA; (4) absence of recommendations for treatment of HCA in men; and (5) approaches to HCA subtype identification on magnetic resonance imaging.

CONCLUSION

Recognising differences in recommendations can assist in harmonisation of practice standards and identify unmet needs in research. This may ultimately contribute to improved global patient care.