Hepatocellular Adenoma Research Articles

HPB SO50 - A comprehensive review of clinical practice guidelines for managing hepatic adenoma

Abstract Background Hepatic adenoma(HCA) are increasingly diagnosed as incidentalomas. Clinical implications and management vary across and within the different types of Hepatic adenomas. Practice guidelines are needed, because of the many variation, diagnostic tools, and conservative and invasive management protocols. Therefore, our aim was to systematically search for available clinical practice guidelines on hepatic adenoma, critically appraise them, and compare management recommendations. Method Systematic literature search was performed by two investigators using appropriate prespecified search terms within the bibliographic databases of MEDLINE, EMBASE, and PubMed. All HCA guidelines published in peer-reviewed, and English language journals were eligible for inclusion. Clinical practice guidelines on HCA were analysed, compared, and critically appraised using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses recommendations (PRISMA) 2020 checklist. Results The literature search yielded unique 199 papers, 187 were excluded after screening of title/abstract, and 9 after full-text screening. Guidelines included were: (EASL; 2016, (ACG; 2014), (SBH; 2015),). There were no set standards in the assessment methods for grading and gravity of recommendations between guidelines. Observed differences were: (1) indications for biopsy; (2) advices on contraceptive pills and follow-up; (3) use of an lesion centred approach to HCA; (4) lack of adequate treatment recommendations of HCA in male population ; and (5) approach to HCA depending on subtype varaition on magnetic resonance imaging. Conclusion Recognising differences in recommendations can assist in formulating practice standards and identify needs for research.

A Multicenter Study on Hepatocellular Adenomas in Korea: Clinicopathological and Imaging Features With an Emphasis on β-Catenin Mutated Subtype.

The clinicopathologic and imaging features of hepatocellular adenomas (HCAs) in Asian population remain unclear. We aimed to analyse clinicopathologic and imaging features of HCAs in Korea and propose an imaging-based method to differentiate β-catenin mutated HCA (βHCA) from other subtypes. This retrospective multicenter study included pathologically confirmed HCAs from three tertiary institutions in Korea between 2010 and 2023. HCA subtypes were determined according to the current World Health Organization classification using immunohistochemical staining. Two abdominal radiologists reviewed computed tomography and magnetic resonance imaging scans. The clinical characteristics and imaging features of HCA subtypes were compared. A scoring system for βHCA was developed and validated using development (January 2010-April 2021) and validation (May 2021-March 2023) cohorts. 121 patients (47 men; mean age, 39.0 years ±13.5) with 138 HCAs were included. HCAs displayed characteristic clinicopathologic features, including a high proportion of male (38.8%) and obese patients (35.5%), with the inflammatory subtype being the most common (38.4%) and a low percentage of patients using oral contraceptive (5.0%). Each HCA subtype demonstrated distinct clinical and imaging features. The scoring system incorporating tumour heterogeneity and iso to high hepatobiliary phase signal intensity on MRI for differentiating βHCA exhibited high performance in both the development (AUC 0.92, 95% CI: 0.87-0.97) and the validation cohort (AUC 0.91, 95% CI: 0.77-1.00). This comprehensive analysis of clinicopathologic and imaging features of HCAs in Korea contributes to the characterisation of HCAs across different geographical regions. The imaging-based scoring system effectively differentiates βHCA.

The role of inflammation induced by necroptosis in the development of fibrosis and liver cancer in novel knockin mouse models fed a western diet.

Non-resolving, chronic inflammation (inflammaging) is believed to play an important role in aging and age-related diseases. The goal of this study was to determine if inflammation induced by necroptosis arising from the liver plays a role in chronic liver disease (CLD) and liver cancer in mice fed a western diet (WD). Necroptosis was induced in liver using two knockin (KI) mouse models that overexpress genes involved in necroptosis (Ripk3 or Mlkl) specifically in liver (i.e., hRipk3-KI and hMlkl-KI mice). These mice and control mice (not overexpressing Ripk3 or Mlkl) were fed a WD (high in fat, sucrose, and cholesterol) starting at 2months of age for 3, 6, and 12months. Feeding the WD induced necroptosis in the control mice, which was further elevated in the hRipk3-KI and hMlkl-KI mice and was associated with a significant increase in inflammation in the livers of the hRipk3-KI and hMlkl-KI mice compared to control mice fed the WD. Overexpressing Ripk3 or Mlkl significantly increased steatosis and fibrosis compared to control mice fed the WD. Mice fed the WD for 12months developed liver tumors (hepatocellular adenomas): 28% of the control mice developing tumors compared to 62% of the hRipk3-KI and hMlkl-KI mice. The hRipk3-KI and hMlkl-KI mice showed significantly more and larger tumor nodules. Our study provides the first direct evidence that inflammation induced by necroptosis arising from hepatocytes can lead to the progression of hepatic steatosis to fibrosis in obese mice that eventually results in an increased incidence in hepatocellular adenomas.

Practical approach to diagnose and manage benign liver masses.

Benign liver lesions are among the most commonly diagnosed abnormalities in liver imaging. They are often discovered incidentally during routine examinations or imaging conducted for unrelated reasons. These can be solid lesions, such as hemangiomas, focal nodular hyperplasia, hepatic adenomas, or cystic lesions. Recent advancements in MRI technology, particularly with hepatocyte-specific contrast agents, have enhanced the characterization of these lesions, reducing the reliance on invasive tissue sampling. Nevertheless, tissue sampling retains a crucial role in the evaluation of indeterminate lesions or those with malignant potential. While most benign liver lesions are asymptomatic, some can become symptomatic, causing discomfort, pain, or bleeding, particularly if the lesion is large. A deep understanding of the molecular underpinnings of the lesions is crucial for tailoring patient management strategies, particularly in distinguishing lesions that require surgical intervention from those that can be monitored. For instance, the molecular subclassification of hepatic adenomas has provided mechanistic insights and identified certain subtypes that are at higher risk of malignancy. Most benign liver lesions can be safely monitored; however, in patients with cirrhosis or a known primary malignancy, a high index of suspicion for cancer is required. It is crucial to carefully evaluate any liver lesion identified in these patients to ensure that indeterminate lesions are not overlooked. Effective management of benign liver lesions involves a multidisciplinary team, including hepatologists, surgeons, and radiologists, ensuring a comprehensive and individualized approach to patient care. This review outlines the clinical presentation of common benign liver lesions, providing a diagnostic and management framework. Emphasis is placed on a personalized approach to minimize patient distress and optimize outcomes by leveraging imaging advancements and multidisciplinary collaboration.

A Rare Case of a Spontaneously Ruptured Hepatocellular Adenoma in the Third Trimester of Pregnancy

A Rare Case of a Spontaneously Ruptured Hepatocellular Adenoma in the Third Trimester of Pregnancy

Pathology and diagnostic approaches to well-differentiated hepatocellular lesions: a narrative review.

Well-differentiated hepatocellular lesions (WDHLs) are liver tumors or nonneoplastic lesions in which the cells closely resemble normal hepatocytes. These lesions often include focal nodular hyperplasia, hepatocellular adenoma, macroregenerative nodule, dysplastic nodule, and well-differentiated hepatocellular carcinoma. The diagnosis of these lesions remains challenging because of their morphological similarities, particularly when examined using needle biopsy. The accurate diagnosis of WDHLs is crucial for patient management and prognosis. This review addresses the histopathological characteristics and diagnostic approaches of WDHLs.

Spontaneous hepatocellular and gastric tumours in African clawed frogs (Xenopus laevis).

Three seven-year-old African clawed frogs (Xenopus laevis) from an animal research facility showed weight loss, coelomic distention and an abnormal swimming gait were euthanised on welfare grounds. A complete necropsy of each animal showed a focal, firm, dark brown to green mass with multifocal haemorrhages in the left liver lobe in two animals and a transmural, firm, beige, multilobulated gastric mass in another animal. Additionally, one of the frogs with the hepatic mass had haemocoeloma. Histologically, the hepatic masses were diagnosed as hepatocellular adenomas and the gastric mass as a gastric carcinoma with trans-coelomic metastases. The three tumours were immunophenotyped using the following antibodies: cytokeratin AE1/AE3, vimentin, E-cadherin, P53 and Ki67 and, additionally, for the hepatic tumours only, synaptophysin, Prox-1, S100 and Sox-9. Masson's trichrome, Periodic acid Schiff and Gram stains was also performed in selected cases. One of the hepatocellular adenomas was weakly positively labelled with E-cadherin whereas the other showed variable positivity for Sox-9 only. Vimentin labelled the stroma and sinusoidal endothelia. Interestingly in the liver, the cytokeratin AE1/AE3 labelling was restricted to the biliary epithelium and sinusoidal endothelia. The gastric carcinoma labelled positively with cytokeratin AE1/AE3 only. This report aims to guide laboratory animal veterinarians to accurately diagnose multi-organ masses in amphibians. To the authors' knowledge, this is the first comprehensive morphological study on a case series of hepatocellular and gastric neoplasia in X. laevis.

Immunohistochemical Glutamine Synthetase As a Surrogate Marker for Beta Catenin (Exon 3 Deletion) in a Rare Case of Hepatic Adenomatosis with Early Malignant Transformation to Well Differentiated Hepatocellular Carcinoma

Abstract Introduction/Objective Hepatic adenomatosis (HA) is a rare entity defined by ≥ 10 hepatocellular adenomas (HCAs). About half of HA cases are asymptomatic and incidentally found. Compared to individual HCAs, HA carries a higher risk of complications including: tumor rupture, bleeding, and an approximate 4.2% overall frequency of malignant transformation. Methods/Case Report A 29-year-old woman presented to the emergency department (ED) requesting a CT scan. She was seen by a gastroenterologist days prior to her ED visit for ongoing sharp rectal pain for 2-3 months. After a recent rectal exam, she was recommended to have a CT abdomen/pelvis to rule out a potential abscess. CT did not show a perianal or perirectal abscess but instead identified a 9.1 cm right hepatic lobe mass. A liver MRI showed a 6.4 x 8.5 cm mass with arterial enhancement. The patient had a prior history of OCP use. She underwent robotic wedge resection of liver segment 6 with cholecystectomy. Gross examination showed a 6 cm tumor with many smaller nodules ranging in size from 0.5-2.2 cm. Our case was submitted entirely for histologic examination. Microscopy demonstrated well differentiated hepatocellular carcinoma (WDHCC) confirmed with positive immunohistochemical (IHC) staining for HepPar1 and Arginase. Tumor cells showed mild patchy cytological atypia, occasional pseudoglands, and architectural atypia with “nodule in nodule growth.” There was reticulin loss in multiple areas and CD34 showed strong diffuse sinusoidal staining. Glypican 3, CRP, and HAA were negative. Low Ki-67, LFABP retention, and absent nuclear staining of beta catenin (BC) were noted. Glutamine synthetase (GS) was diffuse and homogeneous. The gallbladder was unremarkable. Results (if a Case Study enter NA) NA Conclusion This case emphasizes that, despite negative nuclear BC staining, diffuse homogenous staining of GS is a quality surrogate marker for BC mutations (ex. exon 3 deletions). Thorough gross, microscopic, and molecular examination in HA cases is essential for identifying transformation to WDHCC.

Radiologic correlation with fatty liver and adrenal adenoma using dual echo chemical shift magnetic resonance imaging.

Radiologic correlation with fatty liver and adrenal adenoma using dual echo chemical shift magnetic resonance imaging.

The Role of Diffusion-Weighted MRI in Correlation with Contrast-Enhanced MRI and Histopathology in the Evaluation of Focal Liver Lesions.

Accurate diagnosis of focal liver lesions is of utmost importance for theinitiation ofappropriate treatment. This study aims to assess the effectiveness of diffusion-weighted imaging (DWI) in diagnosing focal liver lesions, specifically focusing on differentiating between benign and malignant lesions, distinguishing metastases from primary liver tumors, and identifying various types of both benign and malignant lesions.. The study design is that of a prospective observational study done on 28 cases withfocal liver lesions detected on ultrasound. DWI was done followed by contrast-enhanced MRI (CE-MRI). Identification of the lesion on DWI and apparent diffusion coefficient (ADC) map was madeby using the CE-MRI images as a guide. The signal intensity of the lesion on DWI is determined as either diffusion restriction or no restriction. ADC measurementswere made quantitatively over various regions of interest (ROIs) of the focal liver lesion. All the lesions were confirmed by histopathological examination (HPE) except few benign lesions like simple cysts and few hemangiomas, which were followed up by ultrasonography after six months. Our study included 28 patients with 44 focal liver lesions. Out of 28 patients in this study group (n=28), there were a total of 17 male and 11 female patients. The mean age of the sample population was 50.89±13.40 years. The lesions were more commonly seen is the age group of 41-60 years (57.14%). Out of 44 lesions(n),24 (54.5%) lesionswere benign , 20 (45.45%) were malignant. There were 17 hemangiomas (38.6%), 2 hematomas (4.5%), 2 simple cysts (4.5%), 1 hydatid cyst (2.27%), 2 hepatic adenomas (4.5%), 16 hepatocellular carcinoma (HCC) (36.36%), 3 cholangiocarcinoma (6.8%), and 1 hepatoblastoma (2.27%). DWI has 85% sensitivity and 84.7% specificity for the differentiation of benign from malignant lesions. The mean ADC value of benign lesions was 1.83x10-3mm2/s and the mean ADC of malignant liver lesions was 0.96x10-3mm2/s. In the present study, the average cut off of mean ADC to differentiate benign and malignant bone lesions is 1.3x10-3 mm2/s, with statistically significant p value of 0.001, sensitivity of 95% and specificity of 83.3%. DWI is a valuable imaging technique in the evaluation of focal liver lesions. The ability to differentiate between benign and malignant liver lesions without the need for contrast is a significant benefit, particularly in challenging cases involving uncooperative patients or when contrast administration is contraindicated.

6590 Androgen Derived Hepatocellular Adenoma And Reinitiation Of Gender Affirming Hormone Therapy

Abstract Disclosure: A.L. McKenna: None. Y. Huang: None. L. Yang: None. N. Loo: None. C. Ritchie: None. A. Metcalfe: None. R. Nakhleh: None. M. Krishna: None. S. Thota-Kammili: None. J. Eleazer: None. A.Y. Chang: None. Hepatocellular adenomas (HCA) are uncommon, benign epithelial tumors of the liver. Risk factors include exogenous estrogen or androgen use, and genetic and metabolic syndromes. Management of HCA is delineated by sex assigned at birth; Observation is recommended in an HCA less than 5 cm in an individual assigned female at birth, while resection of an HCA in an individual assigned male at birth is recommended no matter the size due to risk of malignant transformation. What is not known is whether risk is different for individuals with gender incongruence on gender affirming hormone therapy (GAHT). There is limited data on the risk of HCA in this population. One case report of a transgender man who continued GAHT after diagnosis of an HCA though no follow-up information was available. We present follow-up on a transgender man assigned female at birth with multiple hemorrhagic HCA that was re-initiated on GAHT after stabilization of adenomas off GAHT. Unlike prior cases, the molecular profile showed ß-catenin negative, estrogen and androgen receptors positive. This is the first case report to our knowledge reporting detailed follow-up after restarting masculinizing GAHT after diagnosis of HCA. A 24-year-old transgender man presented to the emergency department with right upper quadrant pain. Initial labs were notable for ALT of 239 units per liter (U/L) and AST 165 U/L. Magnetic resonance imaging (MRI) of the abdomen and liver elastogram revealed multiple bilobar hepatic masses, the largest measuring 9.9 cm concerning for hemorrhagic HCA which was subsequently confirmed on liver biopsy. Immunostains were positive for estrogen and androgen receptors. The patient had no history of alcohol or illicit drug use, tattoos, or family history of liver disease. The patient had been treated with 100 mg of intramuscular testosterone cypionate weekly for the past six years for gender incongruence locally. No testosterone concentrations were available from prior to or during acute presentation. Discontinuation of hormone therapy was recommended along with conservative management with frequent MRI. Over the next 19 months, monitoring revealed improvement/resolution of the auto infarcting adenomas with the last MRI noting two stable HCA measuring 2.1 cm and 0.8 cm without new or enlarging liver lesions. Due to gender dysphoria off GAHT, reinitiation of hormone therapy with low dose AndroGel 1.62% topically was prescribed at 18 months after presentation. The patient has been monitored with labs monthly and plans to obtain MRI abdomen every three months. To date, the patient has tolerated reinitiation of therapy. This case demonstrates that patients on masculinizing GAHT who develop HCA can be conservatively managed and monitored based on pathology and that testosterone does not necessarily explain sex differences in the presentation/malignant transformation of HCA cisgender men as opposed to cisgender women. Presentation: 6/3/2024

S4572 Weight Loss is the Boss: Hepatic Adenomas

S4572 Weight Loss is the Boss: Hepatic Adenomas

Genomic and Transcriptomic Profile of HNF1A-Mutated Liver Adenomas Highlights Molecular Signature and Potential Therapeutic Implications.

Hepatocellular adenomas (HAs) are tumors that can develop under different conditions, including in patients harboring a germline mutation in HNF1A. However, little is known about the pathogenesis of such disease. This work aims to better define what mechanisms lie under the development of this condition. Six HAs were sampled from the liver of a 17-year-old male affected by diabetes and multiple hepatic adenomatosis harboring the heterozygous pathogenic germline variant c.815G>A, p.(Arg272His) in HNF1A, which has a dominant negative effect. All HAs were molecularly characterized. Four of them were shown to harbor a second somatic HNF1A variant and one had a mutation in the ARID1A gene, while no additional somatic changes were found in the remaining HA and normal parenchyma. A transcriptomic profile of the same HA samples was also performed. HNF1A biallelic mutations were associated with the up-regulation of several pathways including the tricarboxylic acid cycle, the metabolism of fatty acids, and mTOR signaling while angiogenesis, endothelial and vascular proliferation, cell migration/adhesion, and immune response were down-regulated. Contrariwise, in the tumor harboring the ARID1A variant, angiogenesis was up-modulated while fatty acid metabolism was down-modulated. Histological analyses confirmed the molecular data. Independently of the second mutation, energetic processes and cholesterol metabolism were up-modulated, while the immune response was down-modulated. This work provides a complete molecular signature of HNF1A-associated HAs, analyzing the association between specific HNF1A variants and the development of HA while identifying potential new therapeutic targets for non-surgical treatment.

Spontaneous hepatic hemorrhage as presentation of metastasized papillary thyroid carcinoma: a case report

BackgroundSpontaneous hepatic hemorrhage is a rare condition, most commonly diagnosed in patients with hepatocellular carcinoma or hepatic adenomas, and is seldom caused by metastatic disease. In this case report, we present a patient with spontaneous hepatic hemorrhage due to hepatic metastasis of papillary thyroid carcinoma, an exceptionally rare occurrence.Case presentationThe patient was a 77-year-old white male with a history of atrial fibrillation treated with apixaban. He presented at a local hospital with abdominal pain and nausea. A CT scan revealed a hepatic lesion in segment 3 with an adjacent hematoma. He was referred to our tertiary center and treated conservatively. Further evaluation revealed an intrathoracic goiter containing a tumorous process diagnosed as a papillary thyroid carcinoma (PTC), and the patient subsequently underwent thyroidectomy. A biopsy of the hepatic lesion confirmed it as a PTC metastasis. Due to worsening abdominal pain and anorexia, the patient underwent subacute hepatic segmental resection. Postoperatively, he developed iodine-refractory disease with disseminated metastasis and passed away 22 months after the initial admission.ConclusionsTo our knowledge, this is the first recorded case of metastasized papillary thyroid carcinoma presenting with spontaneous hepatic hemorrhage—adding to the list of rare causes for this condition.

Prognostic analysis of 8 patients with hepatic adenoma undergoing allogeneic hematopoietic stem cell transplantation

Objective: To evaluate the safety of patients with hepatic adenoma undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) . Methods: A retrospective analysis of the clinical characteristics and prognosis of eight patients with hepatic adenoma who underwent allo-HSCT in the Hematology Department of Peking University People's Hospital from January 2010 to March 2024 was conducted. Results: Of the eight patients who underwent allo-HSCT with hepatic adenoma, one patient was considered MDS-h transfusion-dependent and seven had aplastic anemia. The median age of the patients was 23 years (13-48 years). The median time from the diagnosis of AA or MDS to transplantation was 14 years (6-24 years), whereas the median time from taking androgens to diagnosing hepatic adenoma was 9 years (5-13 years). Six cases underwent haplo-HSCT, one case underwent matched unrelated donor HSCT, and one case underwent matched related donor HSCT. All patients achieved neutrophil engraftment at a median time of 11.5 days (11-20 days) and PLT engraftment within 60 days at a median of 19 days (10-37 days) after haplo-HSCT. Moreover, seven patients developed CMV anemia after transplantation, three patients had hemorrhagic cystitis, and two patients developed acute GVHD. During and after transplantation, eight patients did not show severe liver function damage or rupture of hepatic adenoma. In relation to imaging size, four patients showed varying degrees of reduction in hepatic adenoma size after transplantation, whereas four patients did not show significant changes in hepatic adenoma size after transplantation. The median follow-up time was 540.5 (30-2 989) days. Of the eight patients, six survived and two died. Furthermore, no direct correlation was observed between death and hepatic adenoma. Conclusion: Patients with hepatic adenomas undergoing allo-HSCT are not contraindications for transplantation, which will not increase transplant-related mortality.

Insulin-like growth factor-1 deficiency caused by hepatocellular adenoma leads to growth arrest, primary amenorrhea and metabolic syndrome: a case report and 4 years follow up

BackgroundHepatocellular adenoma (HCA) is a rare benign neoplasm, seldom ascribed as the cause of endocrine and metabolic derangement. We herein report a case of primary amenorrhea, growth arrest and metabolic syndrome. En bloc resection of the tumor normalized all the disturbances.Case presentationA 16-year-old girl complained of primary amenorrhea and growth arrest for the past 2 years. Her height and weight were at the 3rd percentile, whereas waist circumference was at the 90th percentile for chronological age. She was hypertensive on admission. Plasma cholesterol, triglyceride and uric acid were elevated. Evaluation of GH/IGF-1 axis showed extremely low IGF-1 concentration, which was unresponsive to hGH stimulation. Computer tomography identified a huge liver mass (18.2 cm×13.7 cm×21 cm). The patient underwent an uneventful open right hepatic lobectomy. The tumor was en bloc resected. Immunohistochemistry indicated an unclassified HCA, which was confirmed by genetic screening. IGF-1 concentration, blood pressure, lipid profile and ovarian function were all normalized after surgery, and the girl had reduction in waist circumference and gain in height during the follow up.ConclusionWe provide evidence that liver-derived IGF-1 has a direct effect on skeletal and pubertal development, blood pressure, visceral adiposity and dyslipidemia independent of insulin resistance and obesity in the circumstance of undernutrition. Though rare, we propose the need to look into HCA cases for the existence of IGF-1 deficiency and its impact on metabolic derangement.

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.

Intra- and interobserver agreement in computed tomography localization of primary nonhematopoietic hepatic masses and comparison with surgical and histopathological outcomes in 21 cats.

Computed tomography (CT) is commonly used in the staging of hepatic masses and for liver lobectomy planning. Mass location is an important factor in determining the feasibility of resection, including surgical technique and the likelihood of surgical complications. The objectives of this retrospective descriptive cross-sectional, observer agreement, method comparison study were to assess the reliability of CT in correctly determining the hepatic division and lobar site of origin of feline primary nonhematopoietic hepatic masses, compared with surgically confirmed locations. Furthermore, it provides an overview of the types and locations of liver masses found in a cohort of cats. Pre- and postcontrast CT images of 21 cats were independently and simultaneously reviewed by two observers. Intra- and interobserver agreements and descriptive statistics on demographic and histological diagnoses were calculated. Based on surgical assessment, it was found that masses most frequently originated from the left hepatic division (13/24, 54%). The most frequent lobar origins were the left lateral (8/24, 33%), left medial (5/24, 21%), and right medial lobes (5/24, 21%). No masses were found originating from the right lateral lobe. CT correctly determined hepatic division and lobar origin in 76% of cases, with good-to-excellent intra- and interobserver agreement. The hepatic division had higher agreements overall for both observers. Most of the masses were benign (17/21, 81%), and the most prevalent histological diagnoses were biliary cystadenoma (11/21, 52%) and hepatocellular adenoma (6/21, 29%). Findings suggest that postcontrast CT is a reliable method for correctly determining hepatic mass division and lobar origin in cats.

Clinical relevance of subtyping CTNNB1‐mutated hepatocellular adenomas: Different risk patterns according to the mutation type

AbstractBackground and AimsBeta‐catenin‐activated hepatocellular adenomas (b‐HCA) with exon 3 (ex3) non‐S45, ex3 S45 or ex7/8 mutations display different glutamine synthetase (GS)‐immunostaining patterns; the latter two show a GS‐positive/CD34‐negative rim contrasting with diffuse CD34 in the HCA core. Our objective was to determine whether discriminating the three b‐HCA mutation subtypes is clinically relevant.MethodsWe analysed the clinicopathological data of the three b‐HCA subtypes (37 resected cases) and compared it with the corresponding subtypes of beta‐catenin‐activated inflammatory HCA (b‐IHCA, 40 cases).ResultsThe mean age of b‐HCA ex7/8 and ex3 S45 were 25.9 and 27.3 years respectively. Clinical bleeding occurred in 67% and 63%, including five cases of pregnant women; malignant transformation was not observed in these two subtypes. The mean age of the b‐HCA ex3 non‐S45 subtype (41 years) was significantly higher; clinical bleeding occurred in 14% while all cases contained malignancy. Such differences in age and clinical complications were not found in the b‐IHCA subtypes. Additionally, we found abnormal vessels in b‐HCA ex3 S45 and ex7/8, near the GS+/CD34− rim, which was not seen in ex3 non‐S45. These vessels can function as an adjunct to discriminate between the b‐HCA subgroups.ConclusionIn our series, b‐HCA ex7/8 and ex3 S45 patients are significantly younger and have higher clinical bleeding risk than b‐HCA ex3 non‐S45 patients who have a higher malignant risk. Hence, in b‐HCA, due to the differences in clinical complications, it is clinically relevant to identify all three subtypes individually.

Tumor in the liver: Six inflammatory pseudotumor patient

Inflammatory pseudotumor (IPT) is a rare liver disease confused with liver tumors. It is a disease that should be known in the differential diagnosis for clinicians as the correct diagnosis of IPT will prevent unnecessary surgery. Demographic datas, diagnoses and imaging modalities of six patients with radiologically and/or histopathologically diagnosed hepatic IPT between 2016 and 2023 were retrospectively analyzed. Four out of six patients were female and median age was 57.5 (47-66). C-reactive protein was higher in four patients, and carbohydrate antigen 19.9 level was higher in one patient. We used magnetic resonance imaging (MRI) for diagnosis in five patients. Only in one patient computed tomography was enough for diagnosis. Tumor locations were segment 5 for two patients, segment 7-8 in two patients, segment 7 in one patient, and 8 in one patient. Liver biopsy was performed in five patients because it could not be distinguished from malignancy by imaging methods. Histopathological results of all these biopsies defined as IPT. Initial tumor median size was 31 (17-55) mm. Two patients were operated on. The first one underwent right hepatectomy due to a 2-fold increase in size within 11 months. The second one had a mass indistinguishable from hepatic adenoma by MRI and underwent nonanatomic resection. In one patient, IPT disappeared completely in the 18th month of follow-up period while it regressed in size in two patients. Two of our patients had a history of recurrent endoscopic retrograde cholangiopancreatography, which we noticed incidentally before IPT was diagnosed. IPTs are liver masses with low malignant potential and may shrink spontaneously during follow-up. We suspected that biliary tract interventions may be the cause of IPT.