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.

Whole-exome sequencing-based mutational profiling of hepatocellular adenoma malignant transformation to hepatocellular carcinoma.

Hepatocellular adenoma (HCA) represents a rare benign hepatic neoplasm with potential for malignant transformation into hepatocellular carcinoma (HCC), yet the underlying mechanism remains elusive. In this study, we investigated the genomic landscape of this process to identify therapeutic strategies for blocking malignant transformation. Using micro-detection techniques, we obtained specimens of adenoma, cancerous neoplasm and adjacent normal liver from three patients undergoing hepatic resection surgery. Whole-exome sequencing (WES) was performed, and genomic interactions between HCA and HCC components within the same tumour were evaluated using somatic variant calling, copy number variation (CNV) analysis, clonality evaluation and mutational signature analysis. Our results revealed genomic heterogeneity among patient cases, yet within each sample, HCA and HCC tissues exhibited a similar mutational landscape, suggesting a high degree of homology. Using nonnegative matrix factorization and phylogenetic trees, we identified shared and distinct mutational characteristics and uncovering necessary pathways associated with HCA-HCC malignant transformation. Remarkably, we found that HCA and HCC shared a common monoclonal origin while displaying significant genetic diversity within HCA-HCC tumours, indicating fundamental genetic connections or evolutionary pathways between the two. Moreover, elevated immune therapy-related markers in these patients suggested heightened sensitivity to immune therapy, providing novel avenues for the treatment of hepatic malignancies. This study sheds light on the genetic mechanisms underlying HCA-HCC progression, offering potential targets for therapeutic intervention and highlighting the promise of immune-based therapies in managing hepatic malignancies.

Previously undiagnosed genetic disease in adult patient with hepatic masses and reported history of congenital hyperinsulinism.

Glycogen storage disease type 1A (GSD1A), also known as Von Gierke's disease, is a rare autosomal recessive disorder affecting glycogen metabolism in the liver. It most commonly presents in infancy with hypoglycaemia and failure to thrive, but cases have been reported as undiagnosed until adulthood. A woman in her early 20s with diabetes mellitus presented with right upper quadrant pain and was found to have several haemorrhagic hepatic adenomas. This patient had insulin-dependent diabetes since a pancreatectomy at age 9 months due to continued episodes of hypoglycaemia and suspected insulinoma. During the hospital stay, the hepatic adenomas were embolised, but significant lactic acidosis and hypoglycaemia continued. Further workup revealed a chronic lactic acid level, during several hospital stays, of above 5 mmol/L. After cytology of hepatic tissue ruled out hepatocellular carcinoma, the patient was discharged and recommended to follow-up for genetic testing, which confirmed the diagnosis of GSD1A.

A case study of a liver transplant-treated patient with glycogen storage disease type Ia presenting with multiple inflammatory hepatic adenomas: an analysis of clinicopathologic and genetic data.

BACKGROUND: Glycogen storage disease (GSD) is a disease caused by excessive deposition of glycogen in tissues due to genetic disorders in glycogen metabolism. Glycogen storage disease type I (GSD-I) is also known as VonGeirk disease and glucose-6-phosphatase deficiency. This disease is inherited in an autosomal recessive manner, and both sexes can be affected. The main symptoms include hypoglycaemia, hepatomegaly, acidosis, hyperlipidaemia, hyperuricaemia, hyperlactataemia, coagulopathy and developmental delay. CASE PRESENTATION: Here, we present the case of a 13-year-old female patient with GSD Ia complicated with multiple inflammatory hepatic adenomas. She presented to the hospital with hepatomegaly, hypoglycaemia, and epistaxis. By clinical manifestations and imaging and laboratory examinations, we suspected that the patient suffered from GSD I. Finally, the diagnosis was confirmed by liver pathology and whole-exome sequencing (WES). WES revealed a synonymous mutation, c.648 G > T (p.L216 = , NM_000151.4), in exon 5 and a frameshift mutation, c.262delG (p.Val88Phefs*14, NM_000151.4), in exon 2 of the G6PC gene. According to the pedigree analysis results of first-generation sequencing, heterozygous mutations of c.648 G > T and c.262delG were obtained from the patient's father and mother. Liver pathology revealed that the solid nodules were hepatocellular hyperplastic lesions, and immunohistochemical (IHC) results revealed positive expression of CD34 (incomplete vascularization), liver fatty acid binding protein (L-FABP) and C-reactive protein (CRP) in nodule hepatocytes and negative expression of ß-catenin and glutamine synthetase (GS). These findings suggest multiple inflammatory hepatocellular adenomas. PAS-stained peripheral hepatocytes that were mostly digested by PAS-D were strongly positive. This patient was finally diagnosed with GSD-Ia complicated with multiple inflammatory hepatic adenomas, briefly treated with nutritional therapy after diagnosis and then underwent living-donor liver allotransplantation. After 14 months of follow-up, the patient recovered well, liver function and blood glucose levels remained normal, and no complications occurred. CONCLUSION: The patient was diagnosed with GSD-Ia combined with multiple inflammatory hepatic adenomas and received liver transplant treatment. For childhood patients who present with hepatomegaly, growth retardation, and laboratory test abnormalities, including hypoglycaemia, hyperuricaemia, and hyperlipidaemia, a diagnosis of GSD should be considered. Gene sequencing and liver pathology play important roles in the diagnosis and typing of GSD.

Indocyanine green (ICG)-guided robotic resection for liver adenoma: combined technologies for precision surgery.

HCA resection is crucial to prevent bleeding and malignant transformation. The aim of this study was to enhance the precision of tumor resection in hepatocellular adenoma (HCA) through the combination of intraoperative ultrasound (IOUS) and indocyanine green (ICG) fluorescence imaging. ICG was intravenously injected 24 h before surgery, enabling positive staining of HCA nodules. IOUS guided the parenchymal transection performed using the RoboLap approach. IOUS combined with ICG effectively demarcated lesions, allowing precision surgery while sparing healthy liver tissue. Intraoperative frozen examination further validated the potential of ICG to identify previously undetected lesions. The study showed promising advantages of ICG in HCA resections, potentially reducing the risk of recurrence and malignant transformation. The combined robotic and laparoscopic approach improved the feasibility of parenchymal-sparing surgery, offering a cautious assessment of HCA lesions.

Dynamic Contrast Enhanced-MRI and Apparent Diffusion Coefficient Quantitation for Differentiate Hepatocellular Carcinoma from Hepatocellular Adenoma.

BACKGROUND: Due to their overlapping radiological characteristics, hepatic lesions, such as hepatocellular carcinoma (HCC) and hepatocellular adenoma (HCA), present a substantial diagnostic challenge. Accurate differentiation between HCC and HCA is essential for the best clinical treatment and therapeutic decision-making. This study aims to assess the potential role of DCE-MRI and Apparent Diffusion Coefficient (ADC) quantitation in the diagnosis of hepatocellular carcinoma (HCC) from hepatocellular adenoma (HCA). METHODS: 103 patients (56 HCC, 47 HCA) with histopathologically proven hepatocellular lesions were the subjects of a cross-sectional investigation. A standardized imaging technique was used for DCE-MRI on all patients. Diffusion-weighted imaging (DWI) provided the ADC values. The diagnostic efficacy of DCE-MRI and ADC in differentiation was evaluated using statistical analyses, such as t-tests and receiver operating characteristic (ROC) curve analysis. SPSS VER 16 was used for the analysis of the collected data. RESULTS: A total of 103 patients (female: male= 52:51, 57.14±3.09 years) were included in the study. The study revealed significant differences in DCE-MRI parameters and ADC values between HCC and HCA lesions. ADC value was significantly lower in HCC than in HCA (p < 0.001). The area under the curve (AUC) was 0.78 (95% CI: 0.69-0.87) for ADC, 0.84 (95% CI: 0.76-0.91) for Ktrans, and 0.72 (95% CI: 0.62-0.82) for Ve. Sensitivity and specificity for ADC were 76.59% and 71.42%, respectively. Also, PPV and NPV of ADC were 69.23% and 78.43%, respectively. Sensitivity and specificity for Ktrans were 82.14% and 76.59%, respectively. Also, PPV and NPV of Ktrans were 80.7% and 78.26%, respectively. CONCLUSION: In conclusion, DCE-MRI-derived parameters, along with ADC values, exhibit promise as non-invasive tools for differentiating HCC from HCA.

Hepatic adenoma: evolution of a more individualized treatment approach.

BACKGROUND: Hepatic adenomas (HAs) are benign, solid liver lesions, which carry a risk of hemorrhage and malignant transformation. This review article highlights the advances in the diagnosis and management of HAs. METHODS: A comprehensive review was performed using MEDLINE/PubMed and Web of Science databases with a search period ending on September 30, 2023. Using PubMed, the terms "hepatocellular," "hepatic," and "adenoma" were searched. RESULTS: HA has been classified into at least 8 subtypes based on molecular pathology, each exhibiting unique histopathologic features, clinical considerations, and risk of malignant transformation. The most common subtype is inflammatory HA, followed by hepatocyte nuclear factor 1α-inactivated HA, ß-catenin exon 3-mutated HA (ßex3-HA), ß-catenin exon 7- or 8-mutated HA, sonic hedgehog HA, and unclassified HA. Magnetic resonance imaging is the best imaging method for diagnosis and can distinguish among HA subtypes based on fat and telangiectasia pathologic characteristics. The risk of malignant transformation varies among molecular subtypes, ranging from <1% to approximately 50%. Up to 42% of HAs present with spontaneous intratumoral hemorrhage and peritoneal hemorrhage. In general, only 15% to 20% of patients require surgery. HA larger than 5 cm are more likely to be complicated by bleeding and malignant transformation, regardless of subtype, and should generally be resected. In particular, ßex3-HA carries a high risk of malignant transformation and can be considered a true precancerous lesion. CONCLUSION: The management of HAs is based on a multidisciplinary approach. Clinical decision-making should integrate information on gender, tumor size, and HA subtyping. In the future, patients with HA will benefit from novel medical therapies tailored to the individual molecular subtypes.

To assess the quantitative features of focal liver lesions in gadoxetic acid enhanced MRI and to determine whether these features can accurately differentiate benign form malignant lesions.

PURPOSE: The study aims at assessing the quantitative features which distinguish focal liver lesions (FLLs) in gadoxetic acid (GA) enhanced liver MRI and at determining whether these features can accurately differentiate benign from malignant lesions. MATERIAL AND METHODS: 107 patients with 180 unequivocal FLLs in previous examinations were included in a single-center retrospective study. All patients underwent a MRI test of the liver with GA. 99 benign and 74 malignant lesions were included. The group of benign lesions consisted of 60 focal nodular hyperplasias (FNH), 22 hemangiomas (HMG), 6 hepatic adenomas (HA), and 11 other benign lesions (1 angiomyolipioma, 6 lesions histopathology diagnoses as benign without further specification, or ones lacking features of malignancy, and 4 lesions radiologically diagnosed as benign which remained stable in the follow-up studies). The group of malignant lesions consisted of primary 51 hepatocellular carcinomas, 12 metastases, and 11 metastases from melanoma malignum (MM meta). 7 FLLs were excluded (4 cases of uncertain histopathological diagnosis, 2 cholangiocarcinomas, and 1 regenerative nodule). For the included lesions ROI (region of interest) measurements were taken by two observers in the T2-w, ADC (apparent diffusion coefficient) and in the T1-w sequence in the hepatobiliary phase (HBP). The interobserver agreement was evaluated with the Wilcoxon test. The Kruskal - Wallis, Mann - Whitney U and post hoc Dunn's tests were applied to assess if there were any significant differences in the ROI values between individual lesions. The variables with the p values of < 0.05 were considered statistically significant. RESULTS: We found significant differences in the ROI values between lesions with p < 0.0001. Strikingly high ROI values in the T2-w sequence were found for HMG. The lowest ADC values were encountered for metastases and MM metastases. The highest ROI values in the HBP were found for FNH, and the lowest for metastases. We also found statistically significant differences in the ROI values between benign and malignant lesions with benign lesions presenting statistically higher ROI values compared to malignant lesions. CONCLUSIONS: There were significant differences in the ROI values among different types of FLLs. The predominant quantitative feature in the T2-w sequence was a strikingly high ROI value for HMG. Benign lesions presented statistically higher ROI values in the T2-w, ADC, and HBP sequences compared to malignant lesions. This was true for all lesions except for HA.

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.

Progestins as a Contributing Factor to Hepatocellular Adenoma: A Case Series and Literature Review.

STUDY OBJECTIVE: To explore the role of progestins as potential contributing factors for the development of hepatocellular adenoma (HA) METHODS: We describe 3 cases of adolescents and young adults who developed HA while on norethindrone (NET), as well as their management. In addition, we provide a comprehensive literature review on the association between progestins and HA. RESULTS: Since 1983, 16 cases of HA in patients on progestins have been reported. Ten patients were on NET and 5 on a prodrug of NET (4 on norethindrone acetate [NETA] and 1 on lynestrenol). One individual had a norgestrel implant. Eight subsequently ceased all hormones: 4 experienced a size reduction, and 3 had complete resolution of their HA. Among our patients, 1 ceased NET and instead had a levonorgestrel intrauterine device inserted, and another swapped from NET to oral medroxyprogesterone acetate. Both experienced complete resolution of their HA. The third ceased NET and underwent a hysterectomy, with size reduction of her HA. CONCLUSION: These cases and the literature review suggest an association between progestin exposure, in particular NET and its prodrugs, and the development of HA. The pathophysiology is unknown but may include peripheral conversion of NET and NETA to ethinyl estradiol or a specific action of 19-nortestosterone derivatives on hepatocytes, especially those with higher systemic doses compared with the levonorgestrel intrauterine device. There are no case reports relating to other forms of progestins, such as 17-hydroxyprogesterone, which may be important when considering alternative therapeutic options in females requiring effective menstrual management who have comorbidities.

Two-year dermal carcinogenicity bioassay of triclosan in B6C3F1 mice.

Triclosan is a widely used antimicrobial agent in personal care products, household items, medical devices, and clinical settings. Due to its extensive use, there is potential for humans in all age groups to receive lifetime exposures to triclosan, yet data on the chronic dermal toxicity/carcinogenicity of triclosan are still lacking. We evaluated the toxicity/carcinogenicity of triclosan administered dermally to B6C3F1 mice for 104 weeks. Groups of 48 male and 48 female B6C3F1 mice received dermal applications of 0, 1.25, 2.7, 5.8, or 12.5 mg triclosan/kg body weight (bw)/day in 95% ethanol, 7 days/week for 104 weeks. Vehicle control animals received 95% ethanol only; untreated, naïve control mice did not receive any treatment. There were no significant differences in survival among the groups. The highest dose of triclosan significantly decreased the body weight of mice in both sexes, but the decrease was ≤ 9%. Minimal-to-mild epidermal hyperplasia, suppurative inflammation (males only), and ulceration (males only) were observed at the application site in the treated groups, with the highest incidence occurring in the 12.5 mg triclosan/kg bw/day group. No tumors were identified at the application site. Female mice had a positive trend in the incidence of pancreatic islet adenoma. In male mice, there were positive trends in the incidences of hepatocellular carcinoma and hepatocellular adenoma or carcinoma (combined), with the increase of carcinoma being significant in the 5.8 and 12.5 mg/kg/day groups and the increase in hepatocellular adenoma or carcinoma (combined) being significant in the 2.7, 5.8, and 12.5 mg/kg/day groups.

Key CT and MRI findings of drug-associated hepatobiliary and pancreatic disorders.

Obtaining an imaging diagnosis of various hepatobiliary and pancreatic disorders caused by certain drugs can often be challenging. Familiarity with these conditions may improve diagnostic accuracy and patient management. This review aimed to describe the imaging findings of drug-associated hepatobiliary and pancreatic disorders and identify suggestions for obtaining a correct diagnosis. We focused on relatively common disorders or those that can present with characteristic imaging findings, such as drug-induced acute hepatitis, sinusoidal obstruction syndrome, focal nodular hyperplasia-like lesions, hepatocellular adenoma, pseudocirrhosis, chemotherapy-associated steatohepatitis, amiodarone deposition in the liver, secondary iron overload, drug-induced pancreatitis, pancreatic enlargement after epoprostenol therapy, ceftriaxone-associated gallbladder pseudolithiasis, immune-related adverse events, and methotrexate-associated lymphoproliferative disorders.

Adenoma Hepatocelular: a propósito de un caso / Hepatocellular adenoma: about a case / Adenoma hepatocelular: sobre um caso

El Adenoma Hepatocelular (AH) es un tumor hepático benigno, su diagnóstico ha avanzado gracias a los avances en los métodos moleculares, facilitaron dividirlos en subtipos, con diferentes pronósticos e indicaciones terapéuticas. Se presenta el caso clínico de una paciente, de 40 años con hallazgo ecográfico de tumor hepático, la Tomografía de Abdomen y Pelvis voluminosa lesión sólida heterogénea, en la Resonancia Magnética compatible con Adenoma esteatósico (asociado a mutación HNF1 alfa). Se decide tratamiento quirúrgico, con resección de los segmentos 6 y 7. La Anatomía patológica concluye: Compatible con el subtipo inflamatorio. Los Adenoma hepáticos (AH) son tumores raros, solitarios de estirpe epitelial, benignos. Se presentan en mujeres de edad fértil y asociado al consumo de anticonceptivos orales y estrógenos. Estos tumores predominan en hígado derecho, con proliferación de células parecidas a los hepatocitos normales, pero desorganizados y sin arquitectura lobular normal, sin ductos biliares ni tejido conectivo de sostén. Los AH así como el resto de los tumores hepáticos benignos, han aumentado su incidencia de la mano con el avance de la imagenología abdominal. La importancia de la diferenciación con el resto de los tumores hepáticos benignos surge del potencial maligno de éstos. Podemos clasificar a los pacientes según el perfil molecular asociado a marcadores inmunohistoquímicos. Los estudios de imagen son fundamentales para la diferenciación tumoral en diagnóstico y planear la terapéutica. El tratamiento será individualizado, determinada por la clínica, la variedad de subtipos, y la evolución. Debido a la complejidad de la enfermedad, el tratamiento de la HA es uno de los mejores ejemplos de abordaje individualizado en unidades hepatobiliares.

Hepatocellular adenoma (HA) is a benign liver tumor, its diagnosis has advanced thanks to advances in molecular methods, which facilitated its division into subtypes, with different prognoses and therapeutic indications. We present the clinical case of a 40-year-old patient with an ultrasound finding of a liver tumor, a voluminous heterogeneous solid lesion on a CT scan of the abdomen and pelvis, compatible with a steatotic adenoma on MRI (associated with HNF1 alpha mutation). Surgical treatment was decided, with resection of segments 6 and 7. The pathology concluded in short: Compatible with the inflammatory subtype. Hepatic adenomas (HA) are rare, solitary, benign epithelial tumors. They occur in women of childbearing age and associated with the consumption of oral contraceptives and estrogens. These tumors predominate in the right liver, with proliferation of cells similar to normal hepatocytes, but disorganized and without normal lobular architecture, without bile ducts or supporting connective tissue. HA, as well as the rest of the benign liver tumors, have increased their incidence in the hand with the advancement of abdominal imaging. The importance of differentiation with the rest of the benign liver tumors arises from the malignant potential of these. We can classify patients according to the molecular profile associated with immunohistochemical markers. Imaging studies are fundamental for tumor differentiation in diagnosis and therapeutic planning. The treatment will be individualized, determined by the clinic, the variety of subtypes, and the evolution. Due to the complexity of the disease, the treatment of AH is one of the best examples of an individualized approach in hepatobiliary units.

O adenoma hepatocelular (AH) éum tumor benigno do fígado, seu diagnóstico avançougraçasaosavanços dos métodos moleculares, que facilitaramsuadivisão em subtipos, com diferentes prognósticos e indicaçõesterapêuticas. Apresentamos o caso clínico de umadoente de 40 anoscomachadoultrassonográfico de tumor hepático, volumosalesão sólida heterogénea à TC de abdómen e pelve, compatívelcom adenoma esteatótico à RM (associado a mutação HNF1 alfa ). Optou-se por tratamentocirúrgico, comressecção dos segmentos 6 e 7. A patologiaconcluiu-se resumidamente: Compatívelcom o subtipo inflamatório. Os adenomas hepáticos (AH) são tumores epiteliais raros, solitários e benignos. Ocorrem em mulheres em idadereprodutiva e associadasao consumo de anticoncepcionaisorais e estrogênios. Esses tumores predominam no fígadodireito, comproliferação de células semelhantesaoshepatócitosnormais, porém desorganizados e semarquitetura lobular normal, sem ductos biliares outecido conjuntivo de sustentação. O HA, assim como os demais tumores hepáticos benignos, têm aumentado suaincidêncianamãocom o avanço da imagem abdominal. A importância da diferenciaçãocom os demais tumores hepáticos benignos decorre do potencial maligno destes. Podemos classificar os pacientes de acordocom o perfil molecular associado a marcadores imuno-histoquímicos. Os estudos de imagemsãofundamentais para a diferenciação tumoral no diagnóstico e planejamentoterapêutico. O tratamento será individualizado, determinado pela clínica, variedade de subtipos e evolução. Pela complexidade da doença, o tratamento da HA é um dos melhoresexemplos de abordagem individualizada nas unidades hepatobiliares.

Estrobolome and Hepatocellular Adenomas-Connecting the Dots of the Gut Microbial ß-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 ß-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 ß-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.

Focal nodular hyperplasia-like nodules arising in the setting of hepatic vascular disorders with portosystemic shunting show ß-catenin activation.

Hepatocellular nodules can develop in the setting of chronic hepatic vascular disorders including those characterized by portosystemic shunts such as Abernethy malformation and post-Fontan procedure. The nodules can range from benign lesions such as regenerative nodules, focal nodular hyperplasia (FNH), and hepatocellular adenoma (HCA) to malignant neoplasms such as hepatocellular carcinoma (HCC). In many instances, these nodules are difficult to place into well-defined categories based on radiologic or histologic features. Nodular lesions that resemble FNH are common in this context and have been described as FNH-like nodules, the nature of which is not well-established. This study examines 6 liver resections from patients with vascular disease characterized by portosystemic shunts. A wide range of nodules were present in these cases, including regenerative nodules (n = 2), FNH and FNH-like (n = 30), HCA (n = 10), HCA-like (n = 13), and HCC (n = 2). Six nodules from 3 patients were categorized as FNH-like due to one or more features such as nodular architecture, fibrous septa, and ductular reaction, but lack of typical map-like glutamine synthetase (GS) staining. Further characterization of these 6 FNH-like nodules showed diffuse GS staining in all nodules (3 diffuse homogeneous, 3 diffuse heterogeneous). Targeted next-generation sequencing identified CTNNB1 alterations in all tested FNH-like nodules (n = 4). These results indicate that FNH-like nodules in the setting of chronic hepatic vascular disorders can be neoplastic. Since the presence of ß-catenin activation portends a potential risk for malignant progression, GS and ß-catenin immunohistochemistry should be obtained in all cases showing FNH-like morphology, with molecular analysis performed in cases with indeterminate staining pattern.

CRP Versus SAA for Identification of Inflammatory Hepatic Adenomas.

Subtyping hepatic adenomas is important for patient management due to differing complication risks. Immunohistochemical staining with C-reactive protein (CRP) and serum amyloid-A (SAA) is widely accepted as a surrogate for molecular classification to identify inflammatory hepatocellular adenomas. Limited data, however, has been published on how these 2 stains compare for sensitivity. We conducted a large, multicenter, retrospective study to examine the sensitivity and staining characteristics of CRP and SAA in inflammatory hepatic adenomas, with focal nodular hyperplasia (FNHs) as a control group. Inflammatory adenomas were identified in 133 patients (average age 37 years, 109 were female). In all, 69.9% of cases were resection specimens and 90.2% of all cases showed positive staining for both CRP and SAA; 10 (7.5%) were positive for CRP only and 3 (2.3%) were positive for SAA only. CRP was more sensitive than SAA (97.74% vs. 92.48%, P -value = 0.0961) and showed more extensive and intense staining, with a significantly higher modified H-score ( P <0.001). Focal nodular hyperplasia can also show positive CRP and SAA staining but with a lower modified H-score ( P <0.0001). Based on beta-catenin and glutamine synthetase staining, 26 of inflammatory adenomas also had beta-catenin activation (19.5%). All 3 cases with positive SAA and negative CRP staining were beta-catenin activated. In contrast, the proportion of cases that were CRP positive and SAA negative was similar regardless of beta-catenin activation. The data affirms the strategy of using both CRP and SAA immunostains for hepatic adenoma subtyping and raises the awareness of the highly variable nature of SAA staining characteristics.