Hepatocellular carcinoma and regenerating nodule in a 3-year-old child with Alagille syndrome

Hepatoblastoma in a cirrhotic child with Alagille syndrome

Alagille syndrome (AGS) is a genetic disorder due to mutations in the JAGGED 1 or NOTCH 2 genes leading to multisystemic manifestations. Though these patients are at risk of developing various liver tumours, no cases of hepatoblastoma among young children with cirrhosis in AGS have been reported. We report a male toddler, with cirrhosis due to AGS who developed a hepatoblastoma. He underwent a liver transplant for decompensated chronic liver disease with marked pruritus, very high alpha-fetoprotein levels and malignant liver lesions on positron emission tomography CT. His explant histology revealed a paucity of bile ducts and liver lesions turned out to be hepatoblastoma for which he received postoperative chemotherapy. The genetic testing sent before transplantation confirmed the clinical diagnosis of AGS. Hepatoblastoma should be suspected in any child with AGS presenting with a right upper quadrant mass even in the setting of chronic liver disease.

Alagille Syndrome: A Focused Review on Clinical Features, Genetics, and Treatment

Alagille syndrome (ALGS) is an autosomal dominant disorder caused by pathogenic variants in JAG1 or NOTCH2, which encode fundamental components of the Notch signaling pathway. Clinical features span multiple organ systems including hepatic, cardiac, vascular, renal, skeletal, craniofacial, and ocular, and occur with variable phenotypic penetrance. Genotype-phenotype correlation studies have not yet shown associations between mutation type and clinical manifestations or severity, and it has been hypothesized that modifier genes may modulate the effects of JAG1 and NOTCH2 pathogenic variants. Medical management is supportive, focusing on clinical manifestations of disease, with liver transplant indicated for severe pruritus, liver synthetic dysfunction, portal hypertension, bone fractures, and/or growth failure. New therapeutic approaches are under investigation, including ileal bile acid transporter (IBAT) inhibitors and other approaches that may involve targeted interventions to augment the Notch signaling pathway in involved tissues.

Central Hepatic Regenerative Nodules in Alagille Syndrome: A Clinicopathological Review

OBJECTIVE

This review aims to highlight the clinicopathological characteristics and differential diagnosis of central hepatic regenerative nodules (CHRNs) in patients with Alagille syndrome.

METHODS

A review of the literature for cases of CHRNs and their differential diagnoses in patients with Alagille syndrome was performed and the main findings were collated.

RESULTS

Large, regenerative hepatic nodules are seen in approximately 30% of patients with Alagille syndrome. They are thought to be a functional adaptation to vascular changes rather than a neoplastic process. The nodules are typically centrally located, and normal hepatic vasculature coursing through the lesions are noted radiologically. Microscopically, they are characterized by well-circumscribed hepatic lesions with preserved architecture, lesser degrees of fibrosis and relative preservation of interlobular bile ducts compared to the background cirrhotic liver.

CONCLUSION

Regenerative nodules are common in Alagille's syndrome, and should be distinguished from hepatocellular carcinomas and adenomas for appropriate management and prognostication.

Alagille syndrome and risk for hepatocellular carcinoma: Need for increased surveillance in adults with mild liver phenotypes

Alagille syndrome (ALGS) is a multisystem autosomal dominant developmental disorder caused predominantly by pathogenic variants in JAGGED1 (JAG1), and also by pathogenic variants in NOTCH2 in a much smaller number of individuals. Clinical presentation is highly variable and includes liver, heart, eye, skeleton, and facial abnormalities, with a subset of individuals also presenting with kidney, vascular, and central nervous system phenotypes. Hepatocellular carcinoma (HCC) is a rare complication of ALGS, though little is known about its incidence or etiology among affected individuals. Previous reports have identified HCC occurrence in both pediatric and adult cases of ALGS. We present a case report of HCC in a 58‐year‐old woman with a pathogenic JAG1 variant and no overt hepatic features of ALGS. Through a comprehensive literature review, we compile all reported pediatric and adult cases, and further highlight one previously reported case of HCC onset in an adult ALGS patient without any hepatic disease features, similar to our own described patient. Our case report and literature review suggest that ALGS‐causing variants could confer risk for developing HCC regardless of phenotypic severity and highlight a need for a cancer screening protocol that would enable early detection and treatment in this at‐risk population.

Hepatocellular carcinoma in an adult with Alagille syndrome: case report and literature review

Alagille syndrome (AS) is an autosomal dominant multisystem disorder which can lead to hepatopathy and the development of focal hepatic lesions. The majority of the hepatic lesions are benign, including regenerative nodules, focal hyperplasia, and adenoma. Hepatocellular carcinoma (HCC) is extremely rare in AS, with very few cases reported in the literature. A 38-year-old man complaining of acute right upper quadrant pain with long-standing diagnosis of Alagille syndrome. On imaging, the patient had a large hepatic mass in the right lobe, with arterial hyperenhancement, washout appearance, and areas of internal hemorrhage. The patient underwent a right hepatectomy and histopathology demonstrated HCC. The patient passed away 3 months after the surgery due to infectious complications. HCC is a rare complication of AS, although rare, it should be considered. This case also emphasizes the need of HCC screening in patients with AS in order to allow an early diagnosis and treatment, which can improve patients' outcome.

Nodular macroregenerative tissue as a pattern of regeneration in cholangiopathic disorders

BACKGROUND

Published case series have described central hepatic macroregenerative nodules or masses as a common feature of Alagille syndrome. Our experience suggests this regenerative pattern can be seen more generally in cholangiopathic disorders.

OBJECTIVE

To define the frequency of central regenerative tissue in Alagille syndrome and other cholangiopathic disorders and to describe the typical appearance of such regenerative tissue.

MATERIALS AND METHODS

We conducted a retrospective study of CT and MR imaging performed in children and young adults with cholangiopathic disorders between January 2000 and June 2016. Two pediatric radiologists reviewed images in consensus for the presence and features of macroregenerative tissue. Tissue histopathology, when available, was retrieved from the medical record.

RESULTS

Of 226 patients with cholangiopathic disorders, 23% (52/226) had macroregenerative tissue, and this tissue was central in 96% (50/52). Tissue was well defined and mass-like in 38% (20/52). Regenerative tissue was most common among the subset of patients with Langerhans cell histiocytosis with hepatic involvement (71%, 5/7) and was identified in 43% (16/37) of patients with Alagille syndrome. Regenerative tissue was iso- to hyperintense on T1-weighted MR sequences in 96% (50/52) of cases and hypointense on T2-weighted MR imaging in 94% (48/51). Arterial phase hyperenhancement was present in only five patients (12% of 43), none of whom showed portal venous phase washout. Histopathology was available for 20 cases, all showing benign regenerative tissue.

CONCLUSION

Central mass-like regeneration appears to be a common regenerative pattern in cholangiopathic disorders and should not be mistaken for malignancy.

Clinical Applications of Contrast-Enhanced Ultrasound in the Pediatric Work-Up of Focal Liver Lesions and Blunt Abdominal Trauma: A Systematic Review

In pediatrics ultrasound has long been viewed more favorably than imaging that exposes patients to radiation and iodinated contrast or requires sedation. It is child-friendly and diagnostic capabilities have been improved with the advent of contrast-enhanced ultrasound (CEUS). The application of CEUS is indeed promising. However, no ultrasound contrast agent manufactured today is registered for pediatric use in Europe. The contrast agent SonoVue^® has recently been approved by the FDA under the name of Lumason^® to be used in hepatic investigations in adults and children. This article reviews the literature with respect to 2 specific applications of CEUS in children: 1) identification of parenchymal injuries following blunt abdominal trauma, and 2) classification of focal liver lesions. Applications were chosen through the CEUS guidelines published by the European Federation of Societies for Ultrasound in Medicine and Biology and World Federation for Ultrasound in Medicine and Biology. Literature was obtained by searching Medline and Pubmed Central (using Pubmed), Scopus database and Embase. CEUS proved to be an effective investigation in the hemodynamically stable child for identifying parenchymal injuries and for the characterization of focal liver lesions. CEUS showed comparable performance to CT and MRI with a specificity of 98% for identifying benign lesions and a negative predictive value of 100%. For the applications reviewed here, CEUS holds promising perspectives and can help reduce radiation exposure and use of iodinated contrast agents in pediatrics, thereby potentially reducing complications in routine imaging.

Giant hepatic regenerative nodules in Alagille syndrome

BACKGROUND

Children with Alagille syndrome undergo surveillance radiologic examinations as they are at risk for developing cirrhosis and hepatocellular carcinoma. There is limited literature on the imaging of liver masses in Alagille syndrome. We report the ultrasound (US) and magnetic resonance imaging (MRI) appearances of incidental benign giant hepatic regenerative nodules in this population.

OBJECTIVE

To describe the imaging findings of giant regenerative nodules in patients with Alagille syndrome.

MATERIALS AND METHODS

A retrospective search of the hospital database was performed to find all cases of hepatic masses in patients with Alagille syndrome during a 10-year period. Imaging, clinical charts, laboratory data and available pathology were reviewed and analyzed and summarized for each patient.

RESULTS

Twenty of 45 patients with confirmed Alagille syndrome had imaging studies. Of those, we identified six with giant focal liver masses. All six patients had large central hepatic masses that were remarkably similar on US and MRI, in addition to having features of cirrhosis. In each case, the mass was located in hepatic segment VIII and imaging showed the mass splaying the main portal venous branches at the hepatic hilum, as well as smaller portal and hepatic venous branches coursing through them. On MRI, signal intensity of the mass was isointense to liver on T1-weighted sequences in four of six patients, but hyperintense on T1 in two of six patients. In all six cases, the mass was hypointense on T2- weighted sequences. The mass post-contrast was isointense to adjacent liver in all phases in five the cases. Five out of six patients had pathological correlation demonstrating preserved ductal architecture confirming the final diagnosis of a regenerative nodule.

CONCLUSION

Giant hepatic regenerative nodules with characteristic US and MR features can occur in patients with Alagille syndrome with underlying cirrhosis. Recognizing these lesions as benign giant hepatic regenerative nodules should, thereby, mitigate any need for intervention.

Magnetic resonance imaging of pancreaticobiliary diseases in children: from technique to practice

Magnetic resonance imaging is useful for evaluating pancreaticobiliary diseases in children after initial sonography, obviating the use of ionizing radiation or invasive procedures such as endoscopic retrograde cholangiopancreatography (ERCP) or transhepatic biliary procedures. Advanced MRI applications have improved depiction of pediatric pancreaticobiliary anatomy and have greatly impacted management of biliary and pancreatic diseases in children. In this article, we review current MRI and magnetic resonance cholangiopancreatography (MRCP) techniques and discuss their role in the assessment of common pancreatic and biliary disorders in children.

Alagille Syndrome Candidates for Liver Transplantation: Differentiation from End-Stage Biliary Atresia Using Preoperative CT

Purpose

To compare preoperative CT findings before liver transplantation between patients with Alagille syndrome (AGS) and those with end-stage biliary atresia (BA).

Materials and Methods

The institutional review board approved this retrospective study. Eleven children with AGS (median age, 19.0 ± 13.0 months; male to female ratio, 3:8) and 109 children with end-stage BA (median age, 17.9 ± 25.8 months; male to female ratio, 37:72) who underwent abdomen CT as candidates for liver transplant were included. CT images were reviewed focusing on hepatic parenchymal changes, vascular changes, presence of focal lesions, and signs of portal hypertension.

Results

Hepatic parenchymal changes were present in 27% (3/11) of AGS patients and 100% (109/109) of end-stage BA patients (P < .001). The hepatic artery diameter was significantly smaller (1.9 mm versus 3.6 mm, P = 008), whereas portal vein diameter was larger (6.8 mm versus 5.0 mm, P < .001) in patients with AGS compared with patients with end-stage BA. No focal lesion was seen in patients with AGS, whereas 44% (48/109) of patients with end-stage BA had intrahepatic biliary cysts (39%, 43/109) and hepatic tumors (8%, 9/109) (P = .008). Splenomegaly was commonly seen in both groups (P = .082), and ascites (9% [1/11] versus 50% [54/109], P = .010) and gastroesophageal varix (0% [0/11] versus 80% [87/109], P < .001) were less common in patients with AGS than in patients with end-stage BA.

Conclusion

Fibrotic or cirrhotic changes of the liver, presence of focal lesions, and relevant portal hypertension were less common in patients with AGS than in patients with end-stage BA.

Solitary Hepatic Nodule Adjacent to the Right Portal Vein: A Common Finding of Alagille Syndrome?

BACKGROUND

Hepatic lesions have been described in Alagille syndrome (ALGS) in isolated case reports, and most of these have been reported to be hepatocellular carcinoma.

OBJECTIVES

The aim of the present study was to determine the frequency, imaging, and histopathologic characteristics of hepatic lesions in children with ALGS.

METHODS

Available abdominal imaging of children with ALGS was retrospectively reviewed to note the presence of any focal liver lesion, its location, and imaging characteristics. Other findings including signs of portal hypertension, portal lymph nodes, and splenic and renal abnormalities were also noted. Findings were correlated with pathology in available cases and with clinical follow-up.

RESULTS

Of 55 children with clinically and/or genetically confirmed ALGS followed in the liver clinic, 39 (19 boys, 20 girls; mean age 8.9 years) with imaging available on picture archival and communication system were included in the study. Focal hepatic lesions were seen in 12 of the 39 (30%) children, solitary in 11 and multiple in 1. Ten of these children had a large nodule adjacent to the right portal vein. The median diameter of the lesions was 8.1 cm (range 5.6-9.8 cm). Magnetic resonance imaging features and pathology in available cases were suggestive of a regenerative nodule. α-fetoprotein levels were normal in all except 1 child who had mild elevation.

CONCLUSIONS

Combining our series and previous case reports, the presence of a large nodule adjacent to the right portal vein appears to be a common finding in ALGS. The typical location, normal α-fetoprotein levels, and magnetic resonance imaging features with vessels coursing through the lesion can reliably differentiate this benign nodule from hepatocellular carcinoma.