Current Approaches in the Management of Hepatic Adenomas

Beta-Catenin-Mutated Hepatocellular Adenomas at Hepatobiliary Phase MRI: A Systematic Review and Meta-Analysis

BACKGROUND

Beta-catenin-mutated hepatocellular adenomas (β-HCAs) can appear iso- to hyperintense at the hepatobiliary phase (HBP) at magnetic resonance imaging (MRI). Given the relatively lower prevalence of β-HCAs, prior studies had limited power to show statistically significant differences in the HBP signal intensity between different subtypes.

PURPOSE

To assess the diagnostic performance of HBP MRI to discriminate β-HCA from other subtypes.

STUDY TYPE

Systemic review and meta-analysis.

POPULATION

Ten original studies were included, yielding 266 patients with 397 HCAs (9%, 36/397 β-HCAs and 91%, 361/397 non-β-HCAs).

FIELD STRENGTH/SEQUENCE

1.5 T and 3.0 T, HBP.

ASSESSMENT

PubMed, Web of Science, and Embase databases were searched from January 1, 2000, to August 31, 2023, for all articles reporting HBP signal intensity in patients with histopathologically proven HCA subtypes. QUADAS-2 was used to assess risk of bias and concerns regarding applicability.

STATISTICAL TESTS

Univariate random-effects model was used to calculate pooled estimates. Heterogeneity estimates were assessed with I2 heterogeneity index. Meta-regression (mixed-effect model) was used to test for differences in the prevalence of HBP signal between HCA groups. The threshold for statistical significance was set at P < 0.05.

RESULTS

HBP iso- to hyperintensity was associated with β-HCAs (pooled prevalence was 72.3% in β-HCAs and 6.3% in non-β-HCAs). Pooled sensitivity and specificity were 72.3% (95% confidence interval 54.1-85.3) and 93.7% (93.8-97.7), respectively. Specificity had substantial heterogeneity with I2 of 83% due to one study, but not for sensitivity (I2 = 0). After excluding this study, pooled sensitivity and specificity were 77.4% (59.6-88.8) and 94.1% (88.9-96.9), with no substantial heterogeneity. One study had high risk of bias for patient selection and two studies were rated unclear for two domains.

DATA CONCLUSION

Iso- to hyperintensity at HBP MRI may help to distinguish β-HCA subtype from other HCAs with high specificity. However, there was heterogeneity in the pooled estimates.

LEVEL OF EVIDENCE

3 TECHNICAL EFFICACY: Stage 2.

Hepatocellular adenoma update: diagnosis, molecular classification, and clinical course

Hepatocellular adenomas (HCA) are acquired focal liver lesions, that occur mainly in young-to-middle-aged women who are on long-term estrogen-containing contraceptives or young men after prolonged use of anabolic steroids. Furthermore, distinct underlying diseases, such as obesity, metabolic dysfunction-associated steatotic liver disease, glycogen storage disease, etc. are considered risk factors. The 2017 Bordeaux classification, in particular Nault et al, divided HCAs into eight subtypes according to their pheno- and genotypic characteristics. This includes HCAs with hepatocyte-nuclear-factor (HNF1-alpha mutation), HCAs with β-catenin mutation, and HCAs without either of these genetic mutations, which are further subdivided into HCAs with and without inflammatory cells. HCAs should no longer be classified as purely benign without histologic workup since three of the eight subtypes are considered high-risk lesions, requiring adequate management: malignant transformation of the pure (ßex3-HCA) and mixed inflammatory/β-catenin exon 3 (ßex3-IHCA) adenomas, as well as potential bleeding of the sonic hedgehog HCA and pure (ßex7/8-HCA) and mixed inflammatory/β-catenin exon 7/8 (ßex7/8-IHCA). Elective surgery is recommended for any HCA in a male, or for any HCA exceeding 5 cm. Although MRI can classify up to 80% of adenomas, if findings are equivocal, biopsy remains the reference standard for adenoma subtype.

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.

Ultrasound-guided thermal ablation versus laparoscopic surgery for focal nodular hyperplasia of the liver: A retrospective controlled study

Purpose

This study aims to evaluate the value of the clinical application of ultrasound-guided percutaneous thermal ablation in focal nodular hyperplasia (FNH) by comparing its safety, effectiveness, and patient experience to surgery in the treatment of hepatic FNH ≤5 cm.

Method

This retrospective study enrolled 82 patients with hepatic FNH having a maximum diameter of ≤5 cm, confirmed by postoperative pathologic diagnosis or needle biopsy, who underwent thermal ablation or surgery between January 2019 and September 2021. Postoperative efficacy, surgical trauma (operation time, intraoperative bleeding volume, liver function, and lost volume of normal liver tissue), postoperative complications (postoperative infection, pleural effusion, and liver dysfunction), patient experience (degree and time of postoperative pain, postoperative fasting time, indwelling thoracic chest drain, and scar size), and economic indices (postoperative hospitalization and total charges) were compared between both groups.

Result

No significant difference existed in postoperative efficacy between both groups (p > 0.05). No recurrent or new lesions were observed during the 6-month follow-up in both groups. However, significant differences were observed in operation time, intraoperative bleeding volume, and lost volume of normal liver tissue (p < 0.05), with significantly less trauma in the thermal ablation group. No statistically significant differences in ALT, AST, and Hb existed between both groups (p > 0.05); however, albumin was higher in the ablation group compared to the surgery group (38.21 ± 3.32 vs. 34.84 ± 3.71 g/L, p < 0.05), and WBC were lower in the ablation group (11.91 ± 3.37 vs. 13.94 ± 3.65/L, p < 0.05). The incidence of postoperative complications in the ablation group was significantly lower than that in the surgery group (p < 0.05). Patient experiences were significantly better than in the surgical group (p < 0.05), with economic indicators being significantly less in the ablation group (p < 0.05).

Conclusion

Ultrasound-guided percutaneous thermal ablation can treat hepatic FNH ≤5 cm with similar clinical efficacy as surgery and is an economical, safe, and minimally invasive treatment method worthy of recommendation.

Deep Learning-Based Classification of Hepatocellular Nodular Lesions on Whole-Slide Histopathologic Images

BACKGROUND & AIMS

Hepatocellular nodular lesions (HNLs) constitute a heterogeneous group of disorders. Differential diagnosis among these lesions, especially high-grade dysplastic nodules (HGDNs) and well-differentiated hepatocellular carcinoma (WD-HCC), can be challenging, let alone biopsy specimens. We aimed to develop a deep learning system to solve these puzzles, improving the histopathologic diagnosis of HNLs (WD-HCC, HGDN, low-grade DN, focal nodular hyperplasia, hepatocellular adenoma), and background tissues (nodular cirrhosis, normal liver tissue).

METHODS

The samples consisting of surgical and biopsy specimens were collected from 6 hospitals. Each specimen was reviewed by 2 to 3 subspecialists. Four deep neural networks (ResNet50, InceptionV3, Xception, and the Ensemble) were used. Their performances were evaluated by confusion matrix, receiver operating characteristic curve, classification map, and heat map. The predictive efficiency of the optimal model was further verified by comparing with that of 9 pathologists.

RESULTS

We obtained 213,280 patches from 1115 whole-slide images of 738 patients. An optimal model was finally chosen based on F1 score and area under the curve value, named hepatocellular-nodular artificial intelligence model (HnAIM), with the overall 7-category area under the curve of 0.935 in the independent external validation cohort. For biopsy specimens, the agreement rate with subspecialists' majority opinion was higher for HnAIM than 9 pathologists on both patch level and whole-slide images level.

CONCLUSIONS

We first developed a deep learning diagnostic model for HNLs, which performed well and contributed to enhancing the diagnosis rate of early HCC and risk stratification of patients with HNLs. Furthermore, HnAIM had significant advantages in patch-level recognition, with important diagnostic implications for fragmentary or scarce biopsy specimens.

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 β-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.

Diagnosis and Follow-up of Incidental Liver Lesions in Children

Incidental liver lesions are identified in children without underlying liver disease or increased risk of hepatic malignancy in childhood. Clinical and imaging evaluation of incidental liver lesions can be complex and may require a multidisciplinary approach. This review aims to summarize the diagnostic process and follow-up of incidental liver lesions based on review of the literature, use of state-of-the-art imaging, and our institutional experience. Age at presentation, gender, alpha fetoprotein levels, tumor size, and imaging characteristics should all be taken into consideration to optimize diagnosis process. Some lesions, such as simple liver cyst, infantile hemangioma, focal nodular hyperplasia (FNH), and focal fatty lesions, have specific imaging characteristics. Recently, contrast-enhanced ultrasound (CEUS) was Food and Drug Administration (FDA)-approved for the evaluation of pediatric liver lesions. CEUS is most specific in lesions smaller than 3 cm and is most useful in the diagnosis of infantile hemangioma, FNH, and focal fatty lesions. The use of hepatobiliary contrast in MRI increases specificity in the diagnosis of FNH. Recently, lesion characteristics in MRI were found to correlate with subtypes of hepatocellular adenomas and associated risk for hemorrhage and malignant transformation. Biopsy should be considered when there are no specific imaging characteristics of a benign lesion. Surveillance with imaging and alpha fetoprotein (AFP) should be performed to confirm the stability of lesions when the diagnosis cannot be determined, and whenever biopsy is not feasible.

An Extreme Case of Liver Adenomatosis: Are They All the Same?

Hepatocellular adenoma (HCA) is a rare and benign liver tumor that affects predominantly young and middle-aged women, especially between 30–40 years old. Liver adenomatosis (LA) is defined as the presence of 10 or more HCA. There are authors that report eight different subtypes of HCA, that correlates with clinical and histopathological features, being the inflammatory subtype the most common. We present a case of a 32-year-old Caucasian woman with a history of self-limited episodes of right abdominal pain and an abdominal ultrasound with multiple hypoechogenic liver nodules, suspected of metastasis. She was taking combined oral contraceptive for 6 years. Magnetic Resonance Imaging (MRI) disclosed around 40 nodules, suggestive of HCA. Liver biopsy confirmed HCA, inflammatory subtype. Oral contraceptive was stopped and control MRI 6 months later disclosed reduction of nodules’ dimensions. Management of patients with LA should be based on the size of the largest tumor, as clinical presentation and risk of bleeding or malignancy do not differ between patients with single or multiple HCAs. However, even with biopsy, there is a risk of missampling, raising concern about the real risk of bleeding and malignant potential in patients with different subtypes coexisting in the same liver.

Regression of multiple hepatocellular adenomas after cessation of oral contraceptive pills: a case report and review of the current literature

Hepatocellular adenoma (HCA) is an uncommon benign liver neoplasm usually solitary and identified incidentally on imaging. We report a case of a 50-year old female who was diagnosed with multiple hepatic adenomas of the inflammatory subtype. After discontinuation of oral contraception a decrease of both the number and size of the liver lesions was seen on magnetic resonance imaging (MRI) without the need of further intervention. The major challenge in the clinical management of patients with multiple HCAs resides in the risk assessment for future complications. In the case of multiple HCAs subtype seemed to be more relevant than the actual number of lesions. Because little is known about the natural evolution in patients with multiple HCAs, we performed a review of the current literature with focus on the different subtypes and their clinical relevance.

A Multicenter, 10-Year Experience With Hepatocellular Adenoma: Risk Factors and Disease Course

BACKGROUND

Management of hepatocellular adenoma (HA) is marked by a paucity of recent studies. Long-term follow-up data from an equal access health care system may facilitate our understanding of the natural disease course of HA and identify modifiable risk factors.

METHODS

A multi-institutional, retrospective review of patients with HA from 2008-2017 was performed. Patient demographics, disease characteristics, and clinical outcomes were analyzed.

RESULTS

Of 124 patients identified, 94% were women with a mean age at diagnosis of 39.5 years (range 20-82). Median follow-up was 22.5 months (range 0-114) with thirty-four (27.4%) patients eventually undergoing hepatectomy. Mean BMI of the study population was 30.5 kg/m² (range 16-72). Stratified by size, average BMI for adenomas ≥5 cm was 34 kg/m² compared to 28 kg/m² for those <5 cm (P < .05). The predominant symptom at presentation was abdominal pain (41.1%), while just 4% presented with acute rupture. Overall incidence of the malignancy was 2.5%. Among all patients, oral contraceptive use was documented in 74 (59.7%) patients, of whom 36 (29.0%) discontinued OC for at least six months. Regression after OC cessation occurred in seven patients (19.4%) while the majority (77.8%) remained stable.

DISCUSSION

This decade-long review analyzing the impact of modifiable risk factors identifies a direct correlation between BMI and hepatocellular adenoma size. Rupture and malignant transformation are rare entities. Cessation of OC appears to be an effective strategy in the management of hepatic adenoma. Further investigations are warranted to determine if addressing modifiable risk factors such as BMI might induce further HA regression.

Hepatocellular adenomas: review of pathological and molecular features

Hepatocellular adenoma (HCA) is a rare benign liver neoplasm which predominantly occurs in women in the reproductive age group taking oral contraception. Since 2002, the terminology HCA has defined an heterogeneous group of neoplastic benign hepatocellular proliferations composed of different subtypes. The genotype-phenotype classification led to the description of 5 well-recognized subtypes based on morphological and immunophenotypical features, that are currently used in practice: HNF1A inactivated HCA, inflammatory HCA, β-catenin mutated HCA, sonic hedgehog HCA, and unclassified HCA. The main complications observed in HCAs are bleeding and malignant transformation. Risk of malignant transformation into hepatocellular carcinoma (HCC), more frequent in men, is also dependent to tumor size and HCA subtype, reaching 40% in β-catenin mutated HCA. The distinction of HCA from well-differentiated HCC remains difficult in some cases, leading to the diagnosis of so-called "atypical/borderline HCA". The management of HCA is now based on multidisciplinary approach including clinicians, radiologists, and pathologists integrating gender, tumor size, and HCA subtyping.

Should bariatric surgery be offered for hepatocellular adenomas in obese patients?

BACKGROUND

Obesity and metabolic syndrome are increasingly recognized as risk factors for development of hepatocellular adenoma (HCA). The implications of weight loss on HCA regression has not been previously reviewed.

OBJECTIVES

To analyze the effects of surgical and nonsurgical weight loss on HCA.

SETTING

University Tertiary Hospital.

METHODS

Literature review of full-text articles from PubMed and Scopus on patients with HCA who underwent surgical or nonsurgical weight loss was performed. Only English language articles were included and editorial comments were excluded. Wilcoxon signed rank test was used for paired data analysis. Spearman correlation was used for correlation between percent excess weight loss (%EWL) and number and size of HCA lesions.

RESULTS

Out of 4 studies, 7 patients were included in this review, all of whom were female. The median preintervention body mass index was 41 kg/m² compared with the postintervention body mass index of 28 kg/m² (P = .002). The %EWL following intervention positively correlated to reduction in number of HCA lesions (%) postintervention, with a Spearman correlation of .78 (P = .04). Similarly, %EWL postintervention was positively correlated, though not statistically significant, to reduction in lesion size (%), with a Spearman correlation of .46 (P = .29). All patients who were candidates for liver resection preintervention based on lesion size > 5 cm avoided liver resection postintervention following surgical and nonsurgical weight loss.

CONCLUSIONS

Effective long-term weight loss by surgical and nonsurgical methods result in regression of HCAs. Weight loss could avoid major liver resections or decrease the morbidity associated with liver surgery. Bariatric surgery should be considered as an option for management of surgically challenging HCAs in carefully selected obese patients. Multicenter long-term trials, while adjusting for cofounding factors, are required to determine the effects of surgical compared with nonsurgical weight loss on maintenance of HCA regression.

Contrast-Enhanced Ultrasound of Focal Liver Masses: A Success Story

The epidemic of increasing fatty liver disease and liver cancer worldwide, and especially in Western society, has given new importance to non-invasive liver imaging. Contrast-enhanced ultrasound (CEUS) using microbubble contrast agents provides unique advantages over computed tomography (CT) and magnetic resonance imaging (MRI), the currently established methods. CEUS provides determination of malignancy and allows excellent differential diagnosis of a focal liver mass, based on arterial phase enhancement patterns and assessment of the timing and intensity of washout. Today, increased use of CEUS has provided safe and rapid diagnosis of incidentally detected liver masses, improved multidisciplinary management of nodules in a cirrhotic liver, facilitated ablative therapy for liver tumors and allowed diagnosis of hepatocellular carcinoma without biopsy. Benefits of CEUS include the dynamic real-time depiction of tumor perfusion and the fact that it is a purely intravascular agent, accurately reflecting tumoral and inflammatory blood flow. CEUS has many similarities to contrast-enhanced CT and MRI but also unique differences, which are described. The integration of CEUS into a multimodality imaging setting optimizes patient care.

Malignant transformation of hepatic adenoma complicated by rupture and hemorrhage: An extremely rare clinical entity

Hepatic adenomas (HAs) are rare benign tumors of the liver and comprise 2% of all liver tumors with an annual incidence of 3-4/100,000 per year in Europe and North America. These tumors may be clinically silent or present with abdominal pain. Although rare, the most important complications associated with this tumor is haemorrhage and malignant transformation to hepatocellular carcinoma. The reported risk of malignant transformation is believed to be 4.2%. We present an extremely rare case report of a young woman on the oral contraceptive pill (OCP) with malignant transformation of a hepatic adenoma complicated additionally by tumor rupture and intraperitoneal bleed. This article therefore highlights the need to carefully evaluate any liver lesion in a young female on the OCP to be a possible adenoma and if confirmed to be so, to consider the potential risks associated with it as well as the need for follow-up imaging in order to avoid life threatening complications.

Case of resected multiple hepatocellular adenomas in a young man with severe obesity

BACKGROUND

Hepatocellular adenoma (HCA) is a rare liver tumor that has the potential for rupture and malignant transformation. Here, we report a case of multiple hepatocellular adenomas (HCAs) that were treated by surgical resection.

CASE PRESENTATION

An 18-year-old man was admitted to our hospital with proteinuria. His height was 176.5 cm, weight was 126 kg, and body mass index was 40 kg/m². A liver tumor was incidentally found on abdominal ultrasonography. Contrast-enhanced computed tomography and gadoxetic acid-enhanced magnetic resonance imaging revealed three hepatic tumors that were 68 mm, 16 mm, and 9 mm in segments 3/4, 8, and 1, respectively. A percutaneous needle biopsy of the largest tumor was performed, the diagnosis of unclassified type HCA was made, and laparoscopic partial liver resection was performed of all three. The postoperative course was uneventful, and the patient was discharged 12 days later. An immunohistochemical examination revealed positivity for serum amyloid A protein, no decrease in fatty acid-binding protein, and negativity for β-catenin, glutamine synthetase, and cytokeratin 7. Therefore, these tumors were diagnosed as inflammatory type HCAs.

CONCLUSIONS

We reported an extremely rare case of multiple resected HCAs in a young, obese Japanese man. Our findings suggest that HCA should be considered in the differential diagnosis of liver tumor in obese patients. Further studies that consider clinical and molecular risk factors are required to establish individualized treatment plans for HCA in obese patients.

Malignant transformation of hepatocellular adenoma in a young female patient after ovulation induction fertility treatment: A case report

BACKGROUND

Hepatocellular adenoma (HCA) is a rare benign liver tumor usually affecting young women with a history of prolonged use of hormonal contraception. Although the majority is asymptomatic, a low proportion may have significant complications such as bleeding or malignancy. Despite responding to the hormonal stimulus, the desire for pregnancy in patients with small HCA is not contraindicated. However, through this work we demonstrate that intensive hormonal therapies such as those used in the treatment of infertility can trigger serious complications

CASE SUMMARY

A 33-year-old female with a 10-year history of oral contraceptive use was diagnosed with a hepatic tumor as an incidental finding in an abdominal ultrasound. The patient showed no symptoms and physical examination was unremarkable. Laboratory functional tests were within normal limits and tests for serum tumor markers were negative. An abdominal magnetic resonance imaging (MRI) was performed, showing a 30 mm × 29 mm focal lesion in segment VI of the liver compatible with HCA or Focal Nodular Hyperplasia with atypical behavior. After a total of six years of follow-up, the patient underwent ovulation induction treatment for infertility. On a following MRI, a suspected malignancy was warned and hence, surgery was decided. The surgical specimen revealed malignant transformation of HCA towards trabecular hepatocarcinoma with dedifferentiated areas. There was non-evidence of tumor recurrence after three years of clinical and imaging follow-up.

CONCLUSION

HCAs can be malignant regardless its size and low-risk appearance on MRI when an ovultation induction therapy is indicated.