Hepatoblastoma in a girl with biliary atresia: coincidence or co-incidence

Small Intestinal Adenocarcinoma Arising at the Anastomotic Site after Kasai Operation for Biliary Atresia: A Case Report and Literature Review

Biliary atresia is an obliterative cholangiopathy of unknown etiology. Hepatic portoenterostomy, in which obliterated extrahepatic bile ducts are resected and bile flow is restored, known as Kasai operation, is performed within 3 months after birth. While this operation enhances long-term survival of patients, the occurrence of primary malignant hepatic tumors has been increasing. We report a case of small intestinal adenocarcinoma arising at the anastomotic site after Kasai operation. A 49-year-old man, who underwent Kasai operation for biliary atresia when he was 2 months old, experienced rapidly progressive jaundice and liver dysfunction. Deceased-donor liver transplantation was performed for liver failure. Macroscopically, there was a white-yellow tumor located at the anastomotic site of hepatic portoenterostomy of the resected liver. Pathological examination revealed a well-differentiated adenocarcinoma with some Paneth cells in the neoplastic lesion. Immunohistochemically, the tumor cells were negative for cytokeratin 7 (CK7) but positive for cytokeratin 20 (CK20) and a homeobox domain-containing transcription factor (CDX2). Mucin expression in tumor cells was negative for mucin 1 (MUC1) and mucin 6 (MUC6) and positive for mucin 2 (MUC2) and mucin 5AC (MUC5AC). The pathological diagnosis was small intestinal adenocarcinoma originating from the jejunum. The patient was discharged 48 days after the operation. The patient had not experienced recurrence at 10 months after the operation. This is the first report of small intestinal adenocarcinoma arising at the anastomotic site after Kasai operation for biliary atresia. Special care should be taken for the patients after Kasai operation with acute progressive jaundice and liver dysfunction because there is a possibility of malignancy in their native liver.

Features of Nodules in Explants of Children Undergoing Liver Transplantation for Biliary Atresia

(1) Background: In patients with biliary atresia (BA) liver nodules can be identified either by pre-transplant imaging or on the explant. This study aimed to (i) analyze the histopathology of liver nodules, and (ii) to correlate histopathology with pretransplant radiological features. (2) Methods: Retrospective analysis of liver nodules in explants of BA patients transplanted in our center (2000−2021). Correlations with pretransplant radiological characteristics, patient age at liver transplantation (LT), time from Kasai hepatoportoenterostomy (KPE) to LT, age at KPE and draining KPE. (3) Results: Of the 63 BA-patients included in the analysis, 27/63 (43%) had nodules on explants. A majority were benign macroregenerative nodules. Premalignant (low-grade and high-grade dysplastic) and malignant (hepatocellular carcinoma) nodules were identified in 6/63 and 2/63 patients, respectively. On pretransplant imaging, only 13/63 (21%) patients had liver nodules, none meeting radiological criteria for malignancy. The occurrence of liver nodules correlated with patient age at LT (p < 0.001), time KPE-LT (p < 0.001) and draining KPE (p = 0.006). (4) Conclusion: In BA patients, pretransplant imaging did not correlate with the presence of liver nodules in explants. Liver nodules were frequent in explanted livers, whereby 25% of explants harboured malignant/pre-malignant nodules, emphasizing the need for careful surveillance in BA children whose clinical course may require LT.

Liver tumors in children with chronic liver diseases

Liver tumors are rare in children, but the incidence may increase in some circumstances and particularly in chronic liver diseases. Most liver tumors consequent to chronic liver diseases are malignant hepatocellular carcinoma. Other liver tumors include hepatoblastoma, focal nodular hyperplasia, adenoma, pseudotumor, and nodular regenerative hyperplasia. Screening of suspected cases is beneficial. Imaging and surrogate markers of alpha-fetoprotein are used initially as noninvasive tools for surveillance. However, liver biopsy for histopathology evaluation might be necessary for patients with inconclusive findings. Once the malignant liver tumor is detected in children with cirrhosis, liver transplantation is currently considered the preferred option and achieves favorable outcomes. Based on the current evidence, this review focuses on liver tumors with underlying chronic liver disease, their epidemiology, pathogenesis, early recognition, and effective management.

Perihilar cholangiocarcinoma in an explanted liver after Kasai operation for biliary atresia: A case report and literature review

Kasai operation is widely performed for biliary atresia (BA), as it improves the prognosis. Biliary tract cancer has rarely been reported as a complication after Kasai operation. A 17-year-old man underwent liver transplantation for progressive jaundice and liver dysfunction after Kasai operation for BA. A macroscopic examination of the explanted liver revealed a 3.6-cm-diameter mass in the hilus of the explanted liver. The tumor consisted of an atypical proliferation of glandular cells in the collagenous stroma. The differential diagnosis included a florid ductular reaction and primary adenocarcinoma. Immunohistochemistry revealed that the glandular cells were diffusely positive for IGF2BP3 and S100P, but negative for CDX2. A diagnosis of extrahepatic cholangiocarcinoma arising from the liver hilus was made. To our knowledge, this is the third case of perihilar cholangiocarcinoma after Kasai operation for BA. The previously reported cases had a poor prognosis, but the current case did not recur during a 15-year follow-up. Cholangiocarcinoma and hepatocellular carcinoma can occur as a late complication of BA after Kasai operation, and early detection and liver transplantation may improve the prognosis.

The Emerging Roles of Cancer Stem Cells and Wnt/Beta-Catenin Signaling in Hepatoblastoma

Hepatoblastoma (HB) is the most common form of primary liver malignancy found in pediatric populations. HB is considered to be clonal and arises from hepatoblasts, or embryonic liver progenitor cells. These less differentiated tumor-initiating progenitor cells, or cancer stem cells (CSCs), may contribute to tumor recurrence and resistance to therapies, and have high metastatic abilities. Phenotypic heterogeneity, undesired genetic and epigenetic alterations, and dysregulated signaling pathways provide CSCs with a survival advantage over current therapies. The molecular and cellular basis of HB and the mechanism of CSC induction are not fully understood. The Wnt/beta-catenin pathway is one of the major developmental pathways and is believed to play an important role in the pathogenesis of HB and CSC formation. This review summarizes the cellular and molecular characteristics of HB with a specific emphasis on CSCs and Wnt/beta-catenin signaling.

Hepatoblastoma in a Child With Early-onset Cirrhosis

Hepatoblastoma is the most common hepatic malignancy of childhood with known genetic predispositions and perinatal risk factors, with rare case reports occurring in the setting of cirrhosis. This case describes a young patient with cirrhosis attributed to early-onset hereditary hemochromatosis who was diagnosed with hepatoblastoma with uncommon histologic findings, evidence of chemotherapy resistance who ultimately succumbed to her disease. It is important to consider diagnoses beyond hepatocellular carcinoma in this scenario and consider early biopsy. With atypical histology, the tumor may respond poorly to conventional treatment and aggressive surgery or intensive therapy should be contemplated.

Hepatoblastoma in Explanted Livers of Patients With Biliary Atresia

OBJECTIVES

Surveillance of hepatic nodules for malignant transformation to hepatocellular carcinoma is important in the monitoring of patients with biliary atresia (BA). To date, only 2 published case reports describe the finding of hepatoblastoma (HB) in this setting. The present study aimed to investigate this association of HB and BA, and to assess the utility of alpha-fetoprotein (aFP) as a marker in the diagnosis.

METHODS

A retrospective study of all patients who underwent isolated liver transplantation (LTx) for the primary diagnosis of BA at a single center, between January 1999 and June 2014, was conducted. Patient demographics, pre-LTx aFP levels, and histologic examination of native liver explants were reviewed.

RESULTS

One hundred two (44% men, median age 11 months) patients underwent LTx for BA. Two (2%) explants examinations were confirmatory for concomitant HB; both patients had abnormally elevated aFP. Overall, 56 (55%) patients had available pre-LTx aFP levels. Recipients with persistently abnormal aFP levels (n = 20, 36%) were older at hepatoportoenterostomy (107 vs 68 days, P = 0.02) and younger at LTx surgery (359 vs 1713 days, P < 0.01), compared to patients with constantly normal levels (n = 24, 43%).

CONCLUSIONS

In our cohort, HB was found to coexist in approximately 2% of patients with BA undergoing LTx, far exceeding the hypothetical anticipated incidence of 1:10 billion for the concomitant diagnoses. Elevated serum aFP levels may be sensitive but not specific for HB in this context. Further research is required to identify specific mechanisms and risk factors.

Biliary atresia: 50 years after the first kasai

Biliary atresia is a rare neonatal disease of unknown etiology, where obstruction of the biliary tree causes severe cholestasis, leading to biliary cirrhosis and death in the first years of life, if the condition is left untreated. Biliary atresia is the most frequent surgical cause of cholestatic jaundice in neonates and should be evoked whenever this clinical sign is associated with pale stools and hepatomegaly. The treatment of biliary atresia is surgical and currently recommended as a sequence of, eventually, two interventions. During the first months of life a hepatoportoenterostomy (a "Kasai," modifications of which are discussed in this paper) should be performed, in order to restore the biliary flow to the intestine and lessen further damage to the liver. If this fails and/or the disease progresses towards biliary cirrhosis and life-threatening complications, then liver transplantation is indicated, for which biliary atresia represents the most frequent pediatric indication. Of importance, the earlier the Kasai is performed, the later a liver transplantation is usually needed. This warrants a great degree of awareness of biliary atresia, and the implementation of systematic screening for this life-threatening pathology.

Liver tumors: pediatric population

Liver tumors in childhood are rare and are typically not detected clinically until they reach a large size and often spread within the organ or metastasize. This can make surgical resection problematic, and almost all of them require extirpation for cure. With very effective chemotherapy for hepatoblastoma and to some extent for sarcomas, many cancers can be shrunk to permit partial hepatectomy, but for most hepatocarcinomas, some of the other malignancies, and even some benign proliferations, their location at the hilum and multiplicity of masses in multiple lobes make transplantation the treatment of choice. Major advances in diagnostic imaging, especially enhanced computed tomography and magnetic resonance imaging, permit a preoperative choice of resection versus transplantation to be achieved in almost all instances, and for the remainder, intraoperative ultrasonography can further help to determine the most desirable approach. The outcome is very much better in the case of hepatoblastoma when transplantation is a primary modality rather than following unsuccessful attempts at resection. In this review, transplantation for liver tumors in children is considered from all aspects, including the importance of screening for tumors whenever possible to avoid the need for transplantation.

Liver stem cells: implications for hepatocarcinogenesis

Numerous studies point to the fact that liver tumors are derived from single cells (monoclonal), but the important question is, which cell? Stem cell biology and cancer are inextricably linked. In continually renewing tissues such as the intestinal mucosa and epidermis, in which a steady flux of cells occurs from the stem cell zone to the terminally differentiated cells that are imminently to be lost, it is widely accepted that cancer is a disease of stem cells, as these are the only cells that persist in the tissue for a sufficient length of time to acquire the requisite number of genetic changes for neoplastic development. In the liver the identity of the founder cells for the two major primary tumors, hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC), is more problematic. The reason for this is that no such obvious unidirectional flux occurs in the liver, though it is held that the centrilobular hepatocytes may be more differentiated (polyploid) and closer to cell senescence than those cells closest to the portal areas. Moreover the existence of bipotential hepatic progenitor cells (HPCs), along with hepatocytes endowed with longevity and long-term repopulating potential suggests there may be more than one type of carcinogen target cell. Irrespective of which target cell is involved, cell proliferation at the time of carcinogen exposure is pivotal for "fixation" of the genotoxic injury into a heritable form. Taking this view, any proliferative cell in the liver can be susceptible to neoplastic transformation. Thus, hepatocytes are implicated in many instances of HCC, direct injury to the biliary epithelium implicates cholangiocytes in some cases of CC, whereas HPC/oval cell activation accompanies very many instances of liver damage irrespective of etiology, making such cells very likely carcinogen targets. Of course, we must qualify this assertion by stating that many carcinogens are both cytotoxic and cytostatic, and that HPC proliferation may be merely a bystander effect of this toxicity. An indepth discussion of causes of cancer in the liver are beyond the scope of this review, but infectious agents (e.g., hepatitis B and C viruses) play a major role, not just in transactivating or otherwise disrupting cellular proto-oncogenes (hepatitis B virus [HBV]), but in also causing chronic inflammation (hepatitis C virus [HCV] and HBV). Sustained epithelial proliferation in a milieu rich in inflammatory cells, growth factors, and DNA-damaging agents (reactive oxygen and nitrogen species produced to fight infection), will lead to permanent genetic changes in proliferating cells. The upregulation of the transcription factor nuclear factor kappaB (NF-kappaB) in transformed hepatocytes, through the paracrine action of tumor necrosis factor-alpha from neighboring endothelia and inflammatory cells, may be critical for tumor progression given the mitogenic and anti-apoptotic properties of proteins encoded by many of NF-kappaB's target genes.

Liver stem cells: implications for hepatocarcinogenesis

Numerous studies point to the fact that liver tumors are derived from single cells (monoclonal), but the important question is, which cell? Stem cell biology and cancer are inextricably linked. In continually renewing tissues such as the intestinal mucosa and epidermis, in which a steady flux of cells occurs from the stem cell zone to the terminally differentiated cells that are imminently to be lost, it is widely accepted that cancer is a disease of stem cells, as these are the only cells that persist in the tissue for a sufficient length of time to acquire the requisite number of genetic changes for neoplastic development. In the liver the identity of the founder cells for the two major primary tumors, hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC), is more problematic. The reason for this is that no such obvious unidirectional flux occurs in the liver, though it is held that the centrilobular hepatocytes may be more differentiated (polyploid) and closer to cell senescence than those cells closest to the portal areas. Moreover the existence of bipotential hepatic progenitor cells (HPCs), along with hepatocytes endowed with longevity and long-term repopulating potential suggests there may be more than one type of carcinogen target cell. Irrespective of which target cell is involved, cell proliferation at the time of carcinogen exposure is pivotal for "fixation" of the genotoxic injury into a heritable form. Taking this view, any proliferative cell in the liver can be susceptible to neoplastic transformation. Thus, hepatocytes are implicated in many instances of HCC, direct injury to the biliary epithelium implicates cholangiocytes in some cases of CC, whereas HPC/oval cell activation accompanies very many instances of liver damage irrespective of etiology, making such cells very likely carcinogen targets. Of course, we must qualify this assertion by stating that many carcinogens are both cytotoxic and cytostatic, and that HPC proliferation may be merely a bystander effect of this toxicity. An indepth discussion of causes of cancer in the liver are beyond the scope of this review, but infectious agents (e.g., hepatitis B and C viruses) play a major role, not just in transactivating or otherwise disrupting cellular proto-oncogenes (hepatitis B virus [HBV]), but in also causing chronic inflammation (hepatitis C virus [HCV] and HBV). Sustained epithelial proliferation in a milieu rich in inflammatory cells, growth factors, and DNA-damaging agents (reactive oxygen and nitrogen species produced to fight infection), will lead to permanent genetic changes in proliferating cells. The upregulation of the transcription factor nuclear factor kappaB (NF-kappaB) in transformed hepatocytes, through the paracrine action of tumor necrosis factor-alpha from neighboring endothelia and inflammatory cells, may be critical for tumor progression given the mitogenic and anti-apoptotic properties of proteins encoded by many of NF-kappaB's target genes.

Liver stem cells: implications for hepatocarcinogenesis

Numerous studies point to the fact that liver tumors are derived from single cells (monoclonal), but the important question is, which cell? Stem cell biology and cancer are inextricably linked. In continually renewing tissues such as the intestinal mucosa and epidermis, in which a steady flux of cells occurs from the stem cell zone to the terminally differentiated cells that are imminently to be lost, it is widely accepted that cancer is a disease of stem cells, as these are the only cells that persist in the tissue for a sufficient length of time to acquire the requisite number of genetic changes for neoplastic development. In the liver the identity of the founder cells for the two major primary tumors, hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC), is more problematic. The reason for this is that no such obvious unidirectional flux occurs in the liver, though it is held that the centrilobular hepatocytes may be more differentiated (polyploid) and closer to cell senescence than those cells closest to the portal areas. Moreover the existence of bipotential hepatic progenitor cells (HPCs), along with hepatocytes endowed with longevity and long-term repopulating potential suggests there may be more than one type of carcinogen target cell. Irrespective of which target cell is involved, cell proliferation at the time of carcinogen exposure is pivotal for "fixation" of the genotoxic injury into a heritable form. Taking this view, any proliferative cell in the liver can be susceptible to neoplastic transformation. Thus, hepatocytes are implicated in many instances of HCC, direct injury to the biliary epithelium implicates cholangiocytes in some cases of CC, whereas HPC/oval cell activation accompanies very many instances of liver damage irrespective of etiology, making such cells very likely carcinogen targets. Of course, we must qualify this assertion by stating that many carcinogens are both cytotoxic and cytostatic, and that HPC proliferation may be merely a bystander effect of this toxicity. An indepth discussion of causes of cancer in the liver are beyond the scope of this review, but infectious agents (e.g., hepatitis B and C viruses) play a major role, not just in transactivating or otherwise disrupting cellular proto-oncogenes (hepatitis B virus [HBV]), but in also causing chronic inflammation (hepatitis C virus [HCV] and HBV). Sustained epithelial proliferation in a milieu rich in inflammatory cells, growth factors, and DNA-damaging agents (reactive oxygen and nitrogen species produced to fight infection), will lead to permanent genetic changes in proliferating cells. The upregulation of the transcription factor nuclear factor kappaB (NF-kappaB) in transformed hepatocytes, through the paracrine action of tumor necrosis factor-alpha from neighboring endothelia and inflammatory cells, may be critical for tumor progression given the mitogenic and anti-apoptotic properties of proteins encoded by many of NF-kappaB's target genes.