[Benign solid liver tumors]. / Benigne solide Lebertumoren.

Benign solid liver tumors are frequently discovered during routine sonographic examinations. As a rule, malignant tumors can be excluded using contrast medium-based sectional imaging; however, unclear cases can represent a diagnostic challenge. The category of solid benign liver tumors includes first and foremost hepatocellular adenoma (HCA), focal nodular hyperplasia (FNH) and hemangioma. Based on the most recent data, an overview of the current standards in the diagnostics and treatment is given.

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, ß-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.

Hepatocellular adenoma: Where are we now?

Hepatocellular adenoma (HCA) is a benign hepatocellular neoplasm, commonly occurs in young women with a history of oral contraceptive use. Complications including hemorrhage and malignant transformation necessitate the need for a thorough understanding of the underlying molecular signatures in this entity. Recent molecular studies have significantly expanded our knowledge of HCAs. The well-developed phenotype-genotype classification system improves clinical management through identifying "high risk" subtype of HCAs. In this article, we attempt to provide updated information on clinical, pathologic and molecular features of each subtype of HCAs.

Large Hepatic Adenomas and Hepatic Adenomatosis: A Multicenter Study of Risk Factors, Interventions, and Complications.

INTRODUCTION: Beyond oral contraceptives (OCs), metabolic factors have been suggested to increase the risk of hepatocellular adenoma (HCA). The impact of risks remains poorly defined, particularly among men and those with adenomatosis. Thus, we aimed to examine HCA clinical and outcome characteristics through a large multicenter cohort. METHODS: HCA diagnosis was made based on a combination of clinical, radiologic, and histologic criteria. Patient and clinical data including follow-up imaging, complications, and interventions were collected between 2004 and 2018 from 3 large academic centers. RESULTS: Among 187 patients (163 female and 24 male) with HCA, 75 had solitary HCA, 58 had multiple HCAs, and 54 had adenomatosis. Over a median follow-up of 3.3 years (quartile 1: 1.2, quartile 3: 8.8), 34 patients (18%) had radiologic interventions, 41 (21%) had surgical resections, 10 (5%) developed tumoral hemorrhage, and 1 had malignant transformation. OC and corticosteroid use were present in 70% and 16%, respectively. Obesity (51%), type 2 diabetes (24%), hypertension (42%), and hypertriglyceridemia (21%) were also common. Metabolic comorbidities were more common in patients with large HCAs and adenomatosis. Compared with women, men had less hepatic steatosis (4% vs 27%), smaller HCAs (2.3 cm vs 4.4 cm), and more corticosteroid use (38% vs 11%) ( P < 0.05 for all). With OC cessation, 69% had a decrease in size of HCA, but 25% eventually required advanced interventions. DISCUSSION: In this large HCA cohort, obesity and metabolic comorbidities were important risk factors associated with large HCAs and adenomatosis. Long-term adverse outcomes were infrequent, 5% had tumor hemorrhage, and 1 patient exhibited malignant transformation.

Non-traumatic spontaneous ruptured hepatocellular adenoma after selective transcatheter arterial chemo-embolization for reduction of tumor mass: A case report.

It is important to detect hepatic adenomas, which are generally well-confined lesions, as urgent treatment is required due to the risk of bleeding and conversion to malignancy. Dimensions can vary between 1 and 15 cm, and the risk of hemorrhage is higher in large and multiple-focus adenomas. The case is here presented of a patient with spontaneous ruptured liver adenoma after selective transcatheter arterial chemo-embolization for reduction of tumor mass, with discussion of the clinical, computed tomography, angiographic findings, and treatment strategies.

A Scoping Review of the Classification, Diagnosis, and Management of Hepatic Adenomas.

BACKGROUND: Hepatic adenomas (HA), or hepatocellular adenomas, are benign, solid liver lesions that develop in otherwise normal livers, often in the setting of increased estrogen levels. While considered a benign tumor, there is a risk for substantial complications such as hemorrhage and malignant transformation. We review the diagnosis, classification, and potential therapeutic management options for patients with HA. METHODS: A scoping narrative review was conducted based on recent literature regarding classification, diagnosis, and management of HA. RESULTS: While HAs are typically considered benign, complications such as hemorrhage and malignant transformation may occur in approximately 25% and 5% of patients, respectively. Recent advances in imaging and molecular profiling have allowed for the classification of HAs into subtypes allowing for patient risk stratification that helps guide management. Surgical resection should be considered in asymptomatic patients who are male, have an adenoma ≥5 cm in diameter, or have the ß-catenin-activated subtype due to an increased risk of hemorrhage and/or malignant transformation. CONCLUSION: Molecular profiling has aided in the stratification of patients relative to the risk of complications to predict better the potential behavior of HAs.

Non-invasive diagnosis and follow-up of benign liver tumours.

Hepatocellular benign liver tumours are mainly developed on normal liver and include hepatic hemangioma, focal nodular hyperplasia and hepatocellular adenoma from the most frequent to the less frequent. The diagnosis of hepatic hemangioma and of simple hepatic biliary cysts can be performed using non-invasive criteria using liver ultrasonography or contrast enhanced MRI. Most of the time the diagnosis of focal nodular hyperplasia can be achieved using contrast-enhanced ultrasonography or contrast enhanced MRI with an additional value of hepatobiliary contrast-agent in this setting. Rarely, if a doubt persists, a tumour and non-tumour liver biopsy can be required in order to establish the diagnosis. As hepatic hemangioma, simple hepatic biliary cysts and focal nodular hyperplasia are not associated with complications, they don't require any treatments or follow-up. Hepatocellular adenomas are mainly diagnosed at histology on surgical samples or liver biopsy even if some radiological features are highly suggestive of several subtypes of hepatocellular adenomas. Finally, the management of hepatocellular adenomas should be guided according to the tumour size, gender but also to the molecular subtypes.

Multidisciplinary Team Management of Hepatocellular Carcinoma Is Standard of Care.

Hepatocellular carcinoma (HCC) is a leading cause of cancer mortality, but unlike other leading causes of cancer death, HCC is increasing in mortality and burden of management. Management of HCC is unique because it usually arises in a diseased liver, which itself may be a driver of mortality. Multidisciplinary teams (MDTs) for the management of complex diseases are becoming more common, but are especially needed in the management of patients with HCC. Liver cancer MDTs are used in most centers providing comprehensive care for patients with HCC, and should be considered the standard of care for these patients.

[Hepatocellular adenoma: update 2020]. / Adénomes hépatocellulaires†: update 2020.

Hepatocellular adenomas (HA) are rare benign liver tumors known to affect mainly women of reproductive age taking oral contraception. They can be complicated by hemorrhage or malignant transformation to hepatocellular carcinoma, especially when the size of the lesion exceeds 5 cm. Magnetic resonance imaging is the most specific tool for the non-invasive characterization of HA. The discovery of mutations underlying different specific HA phenotypes has allowed the establishment of a molecular classification that modified the management of this pathology.

Les adénomes hépatocellulaires (AH) sont des tumeurs bénignes du foie rares et connues pour affecter principalement les femmes en âge de procréer prenant une contraception orale. Ils peuvent se compliquer d'hémorragie ou de transformation en carcinome hépatocellulaire, en particulier lorsque la taille de la lésion dépasse 5 cm. L'imagerie par résonance magnétique est la technique la plus spécifique pour caractériser les AH de manière non invasive. La découverte de mutations spécifiques témoignant de l'existence de différents phénotypes d'AH a permis l'établissement d'une classification moléculaire qui a modifié la prise en charge de cette pathologie.

A Shifting Paradigm in Diagnosis and Management of Hepatic Adenoma.

BACKGROUND: New insights into molecular pathogenesis of hepatocellular adenomas (HCA) have allowed sub-classification based on distinct genetic alterations and a fresh look at characterizations of natural history. Clinically, this is important in understanding risk factors for two feared complications: malignant transformation and hemorrhage. METHODS: PubMed literature search for hepatocellular adenoma over all years, excluding case reports and articles focusing on multiple adenomas or adenomatosis. RESULTS: The ß-catenin exon 3 mutated HCA accounts for about 10% of all HCAs and is associated with the highest risk of malignant transformation. The HF1α subtype accounts for 30-40% of all HCAs and has the lowest risk of malignant transformation. Gender has also emerged as an increasingly important risk factor and males with HCA are at considerably higher risk of malignant transformation, regardless of tumor size. The increasing use of gadoxetic-enhanced MRI has allowed for improved differentiation of HCAs from focal nodular hyperplasia, as well as the identification of specific radiologic features of some subtypes, particularly the inflammatory and HF1α HCAs. CONCLUSIONS: Classification of HCA by subtype has important implications for patient counseling and treatment given variable risks of malignant transformation and hemorrhage. Males and those with ß-catenin exon 3 mutated HCAs are two groups who should always be counselled to undergo surgical resection. On the other hand, in the lower risk HF1α subtype observation is appropriate in lesions < 5 cm and may even be considered in larger lesions as longer follow-up data is aggregated and tumorigenesis is better understood.

A systematic review on the complications and management of hepatic adenomas: a call for a new approach.

Hepatic adenomas are benign hepatic lesions with heterogeneous characteristics. Awareness of complications, including haemorrhage and malignant transformation, has improved alongside a concurrent rise in their detection. Monitoring and management guidelines, however, remain inconsistent. This systematic review analyses the natural history of hepatic adenomas, and existing and novel risk factors associated with haemorrhage and malignant transformation. Results of this systematic review commonly identified male sex, and the beta-catenin histopathological hepatic adenoma subtype, as risk factors for malignant transformation, whilst those associated with haemorrhage included lesion size and number, exophytic nature, and recent hormone use. Overall, females demonstrated higher rates of haemorrhage, whilst males exhibited a higher risk of hepatocellular carcinoma development. This systematic review highlights that tumour size and subtype may not be as characteristically linked with complications as previously thought. We have additionally reported novel risk factors contributing to development of hepatic adenoma-related complications. We conclude by highlighting the risk of taking a conservative approach to seemingly low-risk lesions and suggest revised practice guidelines.

Natural history of liver adenomatosis: A long-term observational study.

BACKGROUND & AIMS: Liver adenomatosis (LA) is characterized by the presence of at least 10 hepatocellular adenomas (HCAs), but the natural history of this rare liver disorder remains unclear. Thus, we aimed to reappraise the natural history and the risk of complications in a cohort of patients with at least 10 HCAs. METHODS: We analyzed the natural history of 40 patients with LA, excluding glycogen storage disorders, in a monocentric cohort. Pathological examination was performed, with immunostaining and molecular biology carried out on surgical specimens or liver biopsies. RESULTS: Forty patients (36 female) were included with a median follow-up of 10.6 (1.9-26.1) years. Six (15%) patients had familial LA, all with germline HNF1A mutations. Median age at diagnosis was 39 (9-55) years. Thirty-three (94%) women had a history of oral contraception, and 29 (81%) women had a pregnancy before LA diagnosis. Overall, thirty-seven (93%) patients underwent surgery at diagnosis. Classification of HCAs showed 46% of patients with HNF1A-mutated HCA, 31% with inflammatory HCA, 3% with sonic hedgehog HCA, 8% with unclassified HCA. Only 15% of the patients demonstrated a "mixed LA" with different HCA subtypes. Hepatic complications were identified in 7 patients: 1 patient (3%) died from recurrent hepatocellular carcinoma after liver transplantation; 6 (15%) had hemorrhages, of which 5 occurred at diagnosis, with 1 fatal case during pregnancy, and 2 occurred in male patients with familial LA. Four patients (10%) had repeated liver resections. Finally, 4 (10%) patients developed extrahepatic malignancies during follow-up. CONCLUSIONS: The diversity in HCA subtypes, as well as the occurrence of bleeding and malignant transformation during long-term follow-up, underline the heterogeneous nature of LA, justifying close and specific management. In patients with germline HNF1A mutation, familial LA occurred equally frequently in males and females, with a higher rate of bleeding in male patients. LAY SUMMARY: Liver adenomatosis is a rare disease characterized by the presence of 10 or more hepatocellular adenomas that may rarely be of genetic origin. Patients with liver adenomatosis have multiple adenomas of different subtypes, with a risk of bleeding and malignant transformation that justify a specific management and follow-up.

Safety and efficacy of transarterial embolization of hepatocellular adenomas.

BACKGROUND: Hepatocellular adenoma (HCA) larger than 5 cm in diameter has an increased risk of haemorrhage and malignant transformation, and is considered an indication for resection. As an alternative to resection, transarterial embolization (TAE) may play a role in prevention of complications of HCA, but its safety and efficacy are largely unknown. The aim of this study was to assess outcomes and postembolization effects of selective TAE in the management of HCA. METHODS: This retrospective, multicentre cohort study included patients aged at least 18 years, diagnosed with HCA and treated with TAE. Patient characteristics, 30-day complications, tumour size before and after TAE, symptoms before and after TAE, and need for secondary interventions were analysed. RESULTS: Overall, 59 patients with a median age of 33.5 years were included from six centres; 57 of the 59 patients were women. Median tumour size at time of TAE was 76 mm. Six of 59 patients (10 per cent) had a major complication (cyst formation or sepsis), which could be resolved with minimal therapy, but prolonged hospital stay. Thirty-four patients (58 per cent) were symptomatic at presentation. There were no significant differences in symptoms before TAE and symptoms evaluated in the short term (within 3 months) after TAE (P = 0·134). First follow-up imaging was performed a median of 5·5 months after TAE and showed a reduction in size to a median of 48 mm (P < 0·001). CONCLUSION: TAE is safe, can lead to adequate size reduction of HCA and, offers an alternative to resection in selected patients.

Development and Validation of a Model to Predict Regression of Large Size Hepatocellular Adenoma.

INTRODUCTION: Surgery is advocated in hepatocellular adenomas (HCA) >5 cm that do not regress to <5 cm after 6-12 months. The aim of this study was to develop a model for these patients, estimating the probability of HCA regression to <5 cm at 1 and 2 years follow-up. METHODS: Data were derived from a multicenter retrospective cohort of female patients diagnosed with HCA >5 cm at first follow-up. Potential predictors included age, body mass index, and HCA diameter at diagnosis (T0), HCA-subtype (hepatocyte nuclear factor 1α inactivated HCA, inflammatory-HCA, unclassified HCA) and "T0-T1 regression-over-time" (percentage of regression between T0 and first follow-up (T1) divided by weeks between T0 and T1). Cox proportional hazards regression was used to develop a multivariable model with time to regression of HCA < 5 cm as outcome. Probabilities at 1 and 2 years follow-up were calculated. RESULTS: In total, 180 female patients were included. Median HCA diameter at T0 was 82.0 mm and at T1 65.0 mm. Eighty-one patients (45%) reached the clinical endpoint of regression to <5 cm after a median of 34 months. No complications occurred during follow-up. In multivariable analysis, the strongest predictors for regression to <5 cm were HCA diameter at T0 (logtransformed, hazard ratio (HR) 0.05), T0-T1 regression-over-time (HR 2.15) and HCA subtype inflammatory-HCA (HR 2.93) and unclassified HCA (HR 2.40), compared to hepatocyte nuclear factor 1α inactivated HCA (reference). The model yielded an internally validated c-index of 0.79. DISCUSSION: In patients diagnosed with HCA > 5 cm that still exceed 5 cm at first follow-up, regression to <5 cm can be predicted at 1 and 2 years follow-up using this model. Although external validation in an independent population is required, this model may aid in decision-making and potentially avoid unnecessary surgery.

Snapshot summary of diagnosis and management of hepatocellular adenoma subtypes.

Hepatocellular adenomas (HCA) are rare benign hepatocellular tumors occurring mainly in women taking oral contraceptives with 2 major complications: severe bleeding and malignant transformation that can be avoided if nodules exceeding 5 cm are resected. This simple attitude has been challenged in the recent years with HCA in men, in young adolescent, in aged persons, and complications in hepatocellular adenomas below 5 cm. The discovery of specific mutations leading to specific phenotypes has modified the clinical spectrum of the disease. The phenotypic immune classification of HCA based on the molecular classification is being widely used in liver referral centers. The aim of this snapshot is to briefly present for each subtype the clinical, pathological, immuno-pathological criteria as well as the risk of complications and guidelines for treatment and management.

Regression of hepatocellular adenoma after bariatric surgery in severe obese patients.

BACKGROUND & AIM: Obesity and metabolic syndrome are increasingly recognized as risk factors for hepatocellular adenomas (HCA). There is still sparse evidence whether weight loss or bariatric surgery could induce HCA regression in these patients. In this brief report we describe the effect of weight loss on HCA regression in severe obese patients that had undergone bariatric surgery in our centre. METHODS: We performed an Electronic Patient Database search and included all patients who underwent bariatric surgery in our bariatric referral centre and had an ICD-10 code of benign neoplasm of liver in our centre from (2006-2017). All imaging studies of eligible patients were re-evaluated by the study radiologist. Primary outcome was change in maximal diameter of HCA. RESULTS: Six of 11 eligible patients were excluded because their lesions were classified as probable focal nodular hyperplasia and two were lost to follow-up. Finally, three women with solitary (n = 1) or multiple HCA (n = 2) and a body mass index (BMI) ranging between 39 and 50 kg/m2 were included. In two patients, HCA completely regressed in 1-2 years following bariatric surgery, after BMI reductions of 36%-48%. The third patient showed a reduction of >50% in diameter of the largest HCA in 2.5 years after bariatric surgery (31% BMI reduction), with complete resolution of smaller HCA. CONCLUSIONS: Bariatric induced weight loss results in significant regression of HCA in severe obese women, which emphasizes the role of overweight in HCA pathophysiology.

[Benign liver tumours - current diagnostics and therapeutic modalities]. / A jóindulatú májdaganatok korszerû diagnosztikája és kezelési elvei.

The most common benign liver tumours are haemangiomas, focal nodular hyperplasia and hepatocellular adenoma. We perform a review of the literature and show the current diagnostic and therapeutic modalities based on the EASL Clinical Practice Guideline. With the widespread use of ultrasound, the detection of liver lesions is increased. They are usually found in women of childbearing age with atypical abdominal pain or incidentally. Contrast-enhanced US, CT or MRI are usually necessary for differential diagnosis. In atypical appearance or in malignancy suspect cases biopsy could be performed. For symptomatic patients conservative therapy can be sufficient. In haemorrhagic cases transarterial embolisation can be useful, also for tumour size decreasing before surgery. In patients with persisting symptoms, with vessel or soft tissue compression effect or in malignancy suspect cases definitive surgical treatment is advised. In men with hepatocellular adenoma primary resection is appropriate because of the higher risk for malignant transformation. As alternative treatment options radiofrequency ablation, irradiation, chemotherapy, monoclonal antibody therapy or liver transplantation are published.

Management and outcome of hepatocellular adenoma with massive bleeding at presentation.

AIM: To evaluate outcome of acute management and risk of rebleeding in patients with massive hemorrhage due to hepatocellular adenoma (HCA). METHODS: This retrospective cohort study included all consecutive patients who presented to our hospital with massive hemorrhage (grade II or III) due to ruptured HCA and were admitted for observation and/or intervention between 1999-2016. The diagnosis of HCA was based on radiological findings from contrast-enhanced magnetic resonance imaging (MRI) or pathological findings from biopsy or resection of the HCA. Hemorrhage was diagnosed based on findings from computed tomography or MRI. Medical records were reviewed for demographic features, clinical presentation, tumor features, initial and subsequent management, short- and long-term complications and patient and lesion follow-up. RESULTS: All patients were female (n = 23). Treatment in the acute phase consisted of embolization (n = 9, 39.1%), conservative therapy (n = 13, 56.5%), and other intervention (n = 1, 4.3%). Median hemoglobin level decreased significantly more on days 0-3 in the intervention group than in the patients initially treated conservatively (0.9 mmol/L vs 2.4 mmol/L respectively, P = 0.006). In total, 4 patients suffered severe short-term complications, which included hypovolemic shock, acute liver failure and abscess formation. After a median follow-up of 36 mo, tumor regression in non-surgically treated patients occurred with a median reduction of 76 mm down to 25 mm. Four patients underwent secondary (elective) treatment (i.e., tumor resection) to address HCA size of > 5 cm and/or desire for future pregnancy. One case of rebleeding was documented (4.3%). None of the patients experienced long-term complication (mean follow-up time: 36 mo). CONCLUSION: With a 4.3% risk of rebleeding, secondary (elective) treatment of HCA after massive hemorrhage may only be considered in patients with persistent HCA > 5 cm.

Systematic review of transarterial embolization for hepatocellular adenomas.

BACKGROUND: Hepatocellular adenoma (HCA) larger than 5 cm in diameter is considered an indication for elective surgery, because of the risk of haemorrhage and malignant transformation. Transarterial embolization (TAE) is used to manage bleeding HCA and occasionally to reduce tumour size. TAE might have potential as an elective therapy, but its current role in this context is uncertain. This systematic review provides an overview of clinical outcomes after TAE, in bleeding and non-bleeding HCA. METHODS: Two independent reviewers performed a systematic search of literature in PubMed and Embase. Outcomes were change in tumour size, avoidance of surgery, complications and malignant transformation after TAE in bleeding and non-bleeding HCA. The Critical Appraisal Skills Programme tool for cohort studies was used for quality assessment of included studies. RESULTS: From 320 potential articles, 20 cohort studies and 20 case reports including 851 patients met the inclusion criteria. TAE was performed in 151 of 851 patients (17·7 per cent), involving 196 tumours, of which 95 (48·5 per cent) were non-bleeding. Surgical treatment was avoided in 68 of 151 patients (45·0 per cent). Elective TAE was performed in 49 patients involving 66 HCAs, with 41 of these patients (84 per cent) not requiring surgery. Major complications occurred in eight of 151 patients (5·3 per cent); no death was reported. Among cohort studies, complete tumour disappearance was observed in 10 per cent of patients, and regression in 75 per cent. CONCLUSION: Acute or elective TAE in the management of HCA is safe. In the elective setting, TAE provides a potential alternative to surgery.