A review of 218 pediatric cases of hepatocellular carcinoma

Incidence and survival of pediatric and adult hepatocellular carcinoma, United States, 2001-2020

BACKGROUND

Hepatocellular carcinoma accounts for approximately 80 % of liver neoplasms. Globally, hepatocellular carcinoma ranks as the third most lethal cancer, with the number of deaths expected to further increase by 2040. In adults, disparities in incidence and survival are well described while pediatric epidemiology is not well characterized. We describe incidence and survival for pediatric (ages 0-19 years) hepatocellular carcinoma cases and compare these measures to adults (ages ≥ 20 years) diagnosed with hepatocellular carcinoma.

METHODS

We assessed incidence data from the US Cancer Statistics database during 2003-2020 and 5-year survival from the National Program of Cancer Registries during 2001-2019. Incidence trends were determined by annual percent change (APC) and average APC (AAPC) using joinpoint regression. Five-year survival was evaluated by relative survival, and all-cause survival was estimated using multivariate Cox modeling. Corresponding 95 % confidence intervals (CI) were calculated for all analyses.

RESULTS

Incidence rate per 100,000 persons was 0.056 (95 %CI:0.052-0.060) for pediatric cases and 7.793 (7.767-7.819) for adults. Incidence was stable in the pediatric population (0.3 AAPC, - 1.1 to 1.7). In contrast, after periods of increase, incidence declined in adults after 2015 (-1.5 APC). Relative survival increased over time for both pediatric and adult ages and was higher for children and adolescents (46.4 %, 95 %CI:42.4-50.3) than adults (20.7 %, 95 %CI:20.5-20.9). Regression modeling showed that non-Hispanic Black race and ethnicity was associated with higher risk of death in children and adolescents (1.48, 95 %CI:1.07-2.05) and adults (1.11, 95 %CI:1.09-1.12) compared to non-Hispanic white race and ethnicity.

CONCLUSIONS

Between 2003 and 2020 in the United States, pediatric incidence was stable while incidence in adults began to decline after 2015. Survival was higher across all stages for children and adolescents compared to adults. Non-Hispanic Black race and ethnicity showed a higher risk of death for both age groups. Further studies could explore the factors that influence these outcome disparities.

Evaluation of surgical strategies and long-term outcomes in pediatric hepatocellular carcinoma

PURPOSE

Hepatocellular carcinoma (HCC), the second most common pediatric malignant liver tumor after hepatoblastoma, represents 1% of all pediatric tumors.

METHODS

A retrospective study was conducted on children with HCC treated at our center from March 2002 to October 2022, excluding those with inadequate follow-up or records. Demographic data, initial complaints, alpha-fetoprotein (AFP) values, underlying disease, size and histopathological features of the masses, chemotherapy, and long-term outcomes were analyzed.

RESULTS

Fifteen patients (8 boys, 7 girls) with a mean age of 11.4 ± 4.1 years (0.8-16.4 years) were analyzed. The majority presented with abdominal pain, with a median AFP of 3.9 ng/mL. Hepatitis B cirrhosis in one patient (6.6%) and metabolic disease (tyrosinemia type 1) in two patients (13.3%) were the underlying diseases. Histopathological diagnoses were fibrolamellar HCC (n:8; 53.3%), HCC (n:6; 40%). Four of the 15 patients underwent liver transplantation, and 9 underwent surgical resection. Due to late diagnosis, two patients were considered inoperable (13.3%). The survival rate for the four patients who underwent liver transplantation was found to be 75%.

CONCLUSION

Surgical treatment of various variants of HCC can be safely performed in experienced centers with a multidisciplinary approach, and outcomes are better than in adults.

Incidence and survival of pediatric and adult hepatocellular carcinoma, United States, 2001-2020

Importance

Hepatocellular carcinoma accounts for approximately 80% of liver neoplasms. Globally, hepatocellular carcinoma ranks as the third most lethal cancer, with the number of deaths expected to further increase by 2040. In adults, disparities in incidence and survival are well described while pediatric epidemiology is not well characterized.

Objective

To describe incidence and survival for pediatric (ages 0-19 years) hepatocellular carcinoma cases and compare these measures to adults (ages ≥20 years) diagnosed with hepatocellular carcinoma. We evaluated demographic factors and clinical characteristics that influence incidence and outcomes.

Design

Population-based cohort study.

Setting

Incidence data from the US Cancer Statistics database from 2003 to 2020 and 5-year relative survival from the National Program of Cancer Registries from 2001 to 2019, covering 97% and 83% of the US population, respectively.

Participants

355,349 US Cancer Statistics and 257,406 the National Program of Cancer Registries patients were identified using ICD-O-3 C22.0 and 8170-5 codes.

Main Outcomes and Measures

Incidence annual percent change (APC) and average APC (AAPC) using joinpoint regression. Five-year relative survival. All-cause survival estimated using multivariate Cox modeling. Corresponding 95% confidence intervals (CI) were calculated.

Results

Incidence rate per 100,000 persons was 0.056 (95%CI:0.052-0.060) for pediatric cases and 7.793 (7.767-7.819) for adults. Incidence was stable in the pediatric population (0.3 AAPC, -1.1-1.7). In contrast, after periods of increase, incidence declined in adults after 2015 (-1.5 APC). Relative survival increased over time for both pediatric and adult ages and was higher for children and adolescents (46.4%, 95%CI:42.4-50.3) than adults (20.7%, 95%CI:20.5-20.9) overall and when stratified by stage. Regression modeling showed that non-Hispanic Black race and ethnicity was associated with higher risk of death in children and adolescents (1.48, 95%CI:1.07-2.05) and adults (1.11, 95%CI:1.09-1.12) compared to non-Hispanic white race and ethnicity.

Conclusions and Relevance

Between 2003 and 2020 in the United States, pediatric incidence was stable while incidence in adults began to decline after 2015. Survival was higher across all stages for children and adolescents compared to adults. Non-Hispanic Black race and ethnicity showed a higher risk of death for both age groups. Further studies could explore the factors that influence these outcome disparities.

Pathologic and Immunophenotypic Characterization of Syncytial Giant Cell Variant of Pediatric Hepatocellular Carcinoma. A Distinct Subtype

INTRODUCTION

Hepatocellular carcinoma (HCC) in pediatrics has a uniformly poor prognosis. Complete surgical resection or liver transplantation remain the only curative options. In contrast to adult HCC, literature on pediatric HCC is sparse and a majority of the distinct subtypes are undefined with regards to their histology, immunohistochemistry and prognosis.

CASE REPORT

Two infants, one with biliary atresia and another with transaldolase deficiency, underwent living donor liver transplants. Explant-liver histopathology revealed tumor with diffuse neoplastic syncytial giant cell pattern. Immunophenotypic characterization highlighted expression of epithelial cell adhesion molecule, alpha fetoprotein and metallothionein.

CONCLUSION

HCC with syncytial giant cells variant can occur in infants with underlying liver disease, specifically in our experience, with biliary atresia and another with transaldolase deficiency.

Incidence and trends of hepatic cancer among children and adolescents in the United States from 2000 to 2017: Evidence from the Surveillance, Epidemiology, and End Results registry data

OBJECTIVE

Primary liver tumors are rare pediatric malignancies. Knowledge of the epidemiology of pediatric liver tumors is limited. This study aims to present the national incidence trends of pediatric liver tumors over 18 years, according to sociodemographic and histological subtype variation.

METHODS

The Surveillance, Epidemiology, and End Results registry was queried from 2000 to 2017 for 1,099 patients between ages 0 and 19 with liver tumors. Age-standardized incidence rates by age, sex, and race/ethnicity were examined among histological subtypes. Annual percentage change (APC) was calculated via joinpoint regression for various sociodemographic and histotype subgroups.

RESULTS

An increase of age-adjusted incidence rate of pediatric hepatic cancers was observed between 2000 and 2017 (APC, 1.7% [95% confidence interval or CI: 0.6%-2.8%], p-value = 0.006), which may likely attribute to the increasing incidence of hepatoblastoma and mesenchymal tumors (APC, 2.5% [95% CI: 1.1%-3.8%], p-value = 0.001). The incidence trend of hepatocellular carcinoma remained stable in the study period. The non-Hispanic Asian/Pacific Islander children and adolescents had a higher risk of hepatic tumors (incidence rate ratio or IRR, 1.42 [95% CI: 1.16-1.72], p-value = 0.0007) when compared with the non-Hispanic white subgroup, while a non-Hispanic black child was associated with a lower incidence rate (IRR, 0.64 [95% CI: 0.50-0.80], p-value < 0.0001). Significantly lower hepatic tumor incidence occurred in females than males, with an incidence rate ratio of 0.69 (95% CI: 0.61-0.78; p-value < 0.0001). Hepatic tumor incidence was also significantly lower in those aged 1-4 years (IRR, 0.47 [95% CI: 0.40-0.54]; p-value < 0.001) and 5-19 years (IRR, 0.09 [95% CI: 0.08-0.10]; p-value < 0.001) when compared with the youngest age group aged less than 1 year. These significant differences were also detected for the subgroup of hepatoblastoma and mesenchymal liver tumors but less among hepatocellular carcinomas (all p-values less than 0.0001).

CONCLUSION

Continued increasing incidence of pediatric hepatoblastoma and mesenchymal liver tumors was discovered and warranted further investigation. Additional findings include a lower incidence of hepatic cancer among non-Hispanic black individuals and higher incidence of hepatic cancer in non-Hispanic Asian/Pacific Islander, male, and aged 1-4-year children and adolescents.

State of the art and perspectives in pediatric hepatocellular carcinoma

Hepatoblastoma (HB) and pediatric hepatocellular carcinoma (HCC) are rare primary malignant liver cancers in children and young adults. HB is the most common and accounts for about 70 % cases; it is usually diagnosed during the first 3 years of life. Instead, pediatric HCC is uncommon, and it is associated with a poor prognosis. Overall, the prognosis of pediatric HCC is dismal with 5-year event-free survival of <30 % as compared to >80 % for HB. Surgery approaches, either resection or transplant, remain the best chance for the cure of pediatric HCC. However, chemotherapy can be helpful as an adjuvant or neoadjuvant treatment. International groups have done trials in pediatric HCC with a chemotherapy regimen, based on cisplatin and doxorubicin (PLADO) as for HB, but the efficacy is limited. Sorafenib, a multi-kinase inhibitor, following positive results in adults and in a pilot study in children, is now tested in conjunction with chemotherapy in the PHITT phase III clinical trial. Some studies have been exploring the genetic profiles of patients to find biological hallmarks that determine the aggressiveness of pediatric HCC. Pathways involved in growth and differentiation are dysregulated and as demonstrated in HB and adult HCC, an important role of the Wnt/CTNNB1 pathway in the pathogenesis of pediatric HCC is also emerging. An extended molecular analysis of tumor samples could give information about pathways as possible targets of biological and immunotherapeutic agents bringing new pharmacological options for the treatment of pediatric HCC.

A Multidisciplinary Approach to the Management of Fibrolamellar Carcinoma: Current Perspectives and Future Prospects

Fibrolamellar carcinoma (FLC) is a rare primary liver tumor affecting predominantly younger and otherwise healthy patients. Typically, FLC presents with advanced disease due to the paucity of typical symptoms and no history of underlying liver disease. Depending on tumor characteristics and the patient's general condition, surgical treatment is the most promising treatment modality. Aggressive resection and liver transplantation have been utilized and are presently indispensable curative treatment options. Under certain circumstances surgical resection is also possible for metachronous metastases or local recurrence. Recent tumor biology discoveries have contributed to improved diagnostic specificity and systemic treatment options.

Improved Survival and Higher Rates of Surgical Resection Associated with Hepatocellular Carcinoma in Children as Compared to Young Adults

Hepatocellular adenocarcinoma (HCC) is the second most common primary hepatic malignancy in children with a 5-year overall survival of 30%. Few studies have examined the similarities and differences between pediatric and adult HCC. This paper aims to examine the relationship between tumor characteristics, treatments, and outcomes in pediatric and adult patients with HCC. The 2019 National Cancer Database was queried for patients with HCC. Patients were stratified by age: pediatric <21 years (n = 214) and young adults 21-40 (n = 1102). Descriptive statistics and chi square were performed. The mean age at diagnosis was 15.5 years (SD 5.6) in the pediatric and 33 years (5.3) in the adult group. Children had a comparable rate of metastasis (30% vs 28%, P = 0.47) and increased fibrolamellar histology (32% vs 9%). Surgical resection was more common in children compared with adults (74% vs 62%, P < 0.001), children also had more lymph nodes examined (39% vs 19%, P < 0.001), positive lymph nodes (35% vs 17%, P = 0.02), and surgical resection when metastasis were present at diagnosis (46% vs 18%, P < 0.001). The 1, 3, and 5-year overall survival was higher for pediatric patients than adults (81%, 65%, 55%, vs 70%, 54%, 48%,) Despite higher prevalence of fibrolamellar histology, greater number of positive lymph nodes, and comparable rates of metastasis at diagnosis, children with HCC have improved overall survival compared with adults. Age did not significantly contribute to survivorship, so it is likely that the more aggressive surgical approach contributed to the improved overall survival in pediatric patients. This article is protected by copyright. All rights reserved.

Managing Hepatocellular Carcinoma in Children

Hepatocellular carcinoma (HCC) is a rare pediatric tumor. It differs from its adult counterpart in many ways like etiology, biological behavior, and association with cirrhosis. Treating HCC requires a multidisciplinary team involving pediatric gastroenterology, oncology, hepatobiliary surgery, and interventional radiology. This case series aims to describe presenting features and management plan of three children with HCC treated at a tertiary care liver transplant center in Pakistan.

Histologic type predicts disparate outcomes in pediatric hepatocellular neoplasms: A Pediatric Surgical Oncology Research Collaborative study

BACKGROUND

Hepatocellular carcinoma (HCC) is a rare cancer in children, with various histologic subtypes and a paucity of data to guide clinical management and predict prognosis.

METHODS

A multi-institutional review of children with hepatocellular neoplasms was performed, including demographic, staging, treatment, and outcomes data. Patients were categorized as having conventional HCC (cHCC) with or without underlying liver disease, fibrolamellar carcinoma (FLC), and hepatoblastoma with HCC features (HB-HCC). Univariate and multivariate analyses identified predictors of mortality and relapse.

RESULTS

In total, 262 children were identified; and an institutional histologic review revealed 110 cHCCs (42%; 69 normal background liver, 34 inflammatory/cirrhotic, 7 unknown), 119 FLCs (45%), and 33 HB-HCCs (12%). The authors observed notable differences in presentation and behavior among tumor subtypes, including increased lymph node involvement in FLC and higher stage in cHCC. Factors associated with mortality included cHCC (hazard ratio [HR], 1.63; P = .038), elevated α-fetoprotein (HR, 3.1; P = .014), multifocality (HR, 2.4; P < .001), and PRETEXT (pretreatment extent of disease) stage IV (HR, 5.76; P < .001). Multivariate analysis identified increased mortality in cHCC versus FLC (HR, 2.2; P = .004) and in unresectable tumors (HR, 3.4; P < .001). Disease-free status at any point predicted survival.

CONCLUSIONS

This multi-institutional, detailed data set allowed a comprehensive analysis of outcomes for children with these rare hepatocellular neoplasms. The current data demonstrated that pediatric HCC subtypes are not equivalent entities because FLC and cHCC have distinct anatomic patterns and outcomes in concert with their known molecular differences. This data set will be further used to elucidate the impact of histology on specific treatment responses, with the goal of designing risk-stratified algorithms for children with HCC.

LAY SUMMARY

This is the largest reported granular data set on children with hepatocellular carcinoma. The study evaluates different subtypes of hepatocellular carcinoma and identifies key differences between subtypes. This information is pivotal in improving understanding of these rare cancers and may be used to improve clinical management and subsequent outcome in children with these rare malignancies.

Stable liver graft post anti-PD1 therapy as a bridge to transplantation in an adolescent with hepatocellular carcinoma

BACKGROUND

Immunotherapy, specifically immune checkpoint inhibitors (ICIs), including anti-programmed cell death 1 (anti-PD1), has recently received clinical approval for the treatment of adult hepatocellular carcinoma (HCC). However, the safety and efficacy of ICIs prior to solid organ transplant are unknown, especially in pediatrics. Safety reports are variable in adults, with some series describing subsequent allograft rejection and loss while others report successful transplants without allograft rejection.As ICIs stimulate the immune system by blocking the interaction between PD1 and the ligand-receptor pair programmed cell death-ligand 1 (PDL1), the downstream effects of T-cell activation increase the risk of graft rejection.

METHODS

Here, we present a case of an adolescent with moderately differentiated non-fibrolamellar HCC treated with pembrolizumab, an anti-PD1 therapy, who subsequently underwent successful orthotopic liver transplantation (OLT).

RESULTS

Our patient received an OLT 138 days from the last pembrolizumab dose with graft preservation. The patient has no evidence of recurrent disease or any episode of allograft rejection 48 months post OLT. Staining of tumor and normal tissues from longitudinal specimens finds PDL1 positive Kupffer cells present in normal liver and peritumoral areas with no changes post anti-PD1 therapy. In contrast, tumor cells were negative for PDL1.

CONCLUSION

This case represents a basis for optimism in potential use of anti-PD1 therapy in liver transplant candidates and supports further investigation of immune checkpoint inhibitors use in this unique patient population.

Diagnosis and Follow-up of Incidental Liver Lesions in Children

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

Pediatric Liver Tumors: Updates in Classification

Malignant primary liver tumors are rare in children. Yet a wide histologic spectrum is seen, particularly in hepatoblastoma, the most common malignant liver tumor in children. Furthermore, there can be significant morphologic overlap with hepatocellular carcinoma, the second most common pediatric liver malignancy, and tumors with hybrid features of hepatoblastoma and hepatocellular carcinoma are also reported (currently placed in the provisional category of malignant hepatocellular neoplasm, not otherwise specified). This review provides detailed morphologic descriptions and updates in the evolving clinical context of these tumors, and presents recent molecular advances that may further help in accurate classification of these tumors, which is critical in their management.

Imaging and clinical features of pediatric hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is rare in children and there is limited data on its imaging features.

OBJECTIVE

To describe imaging features of pediatric HCC and correlate them with clinical and laboratory findings.

MATERIALS AND METHODS

We retrospectively reviewed imaging in all pediatric HCC cases seen between January 2000 and January 2019. Imaging features defined in LI-RADS (Liver Imaging Reporting and Data System) and tumor extent by PRETEXT (pretreatment extent of disease) criteria were noted by two radiologists. Patient charts were reviewed to collect clinical features, alpha-fetoprotein (AFP) level and pathology findings.

RESULTS

Of the 15 children (7 boys, 8 girls; mean age: 11.8 years, age range: 6-17 years) included in the study, 12/15 had computed tomography, 9/15 had magnetic resonance imaging and 9/15 had ultrasound exams available for review. Pathological types of HCC included classic (11/15, 73%), fibrolamellar (3/15, 20%) and mixed cholangiocarcinoma-HCC (1/15, 7%). Eighty percent occurred de novo in normal liver and 67% showed elevated AFP levels. Arterial phase hyperenhancement was seen in 83% of cases, washout in 86%, capsule in 50% and tumor-in-vein in 33%. The mean tumor size was 9.8 cm and 40% were multifocal on imaging. Staging revealed PRETEXT II tumors in 47%, III in 20% and IV in 33%. There were no PRETEXT I tumors. The two most common PRETEXT annotation factors were portal vein and caudate lobe involvement in 71% and 43% of cases, respectively. Fibrolamellar HCC demonstrated central scar, normal AFP levels and normal background liver.

CONCLUSION

Pediatric HCC are large heterogeneous tumors, as reflected by high PRETEXT staging, and commonly include portal vein and caudate involvement. This affects resectability of these tumors at presentation. Central scar, normal AFP level and normal liver background may help differentiate fibrolamellar HCC from other types of HCC.

Fibrolamellar carcinoma: An entity all its own

Fibrolamellar carcinoma (FLC) is a rare malignant entity arising from the liver and primarily affecting patients in late adolescence and young adulthood. FLC tumors are characterized by their unique histologic features and an only recently discovered genomic alteration: a chimeric fusion protein found in nearly all tumors. The rarity of these tumors coupled with the only recent acknowledgement of this genomic abnormality has likely led to disease under-recognition and de-prioritization of collaborative efforts aimed at establishing an evidence-guided standard of care. Surgical resection undoubtedly remains a mainstay of therapy and a necessity for cure but given the incidence of metastatic disease at diagnosis and high rates of distant relapse, systemic therapies remain a key component of disease control. There are few systemic therapies that have demonstrated proven benefit. Recent efforts have galvanized around single-institute or small consortia-based studies specifically focused on the enrollment of patients with FLC or use of agents with biologic rationale. This review will outline the current state of FLC epidemiology, histology, biology and trialed therapies derived from available published literature.

Hepatocellular carcinoma as a complication of Niemann-Pick disease type C1

Niemann-Pick disease type C (NPC) is a rare and fatal lysosomal storage disorder characterized by neurodegeneration and hepatic involvement. Mutations in either NPC1 or NPC2, two genes encoding lysosomal proteins, lead to an intracellular accumulation of unesterified cholesterol and sphingolipids in late endosomes/lysosomes. Early cholestatic disease is considered a hallmark of patients with early disease onset. This can potentially result in liver failure shortly after birth or subclinical hepatic inflammation. Previous reports suggest an association between NPC and hepatocellular carcinoma, a cancer that is rare during childhood. We present a 12-year-old male with a known diagnosis of NPC1 disease who was found to have a stage III hepatocellular carcinoma, underwent surgical resection with adjuvant chemotherapy, and subsequently died from metastatic disease. This report provides evidence of an increased risk of hepatocellular carcinoma in NPC patients, suggesting a need for screening in this patient population.

Pharmacokinetically guided dosing of oral sorafenib in pediatric hepatocellular carcinoma: A simulation study

Sorafenib improves outcomes in adult hepatocellular carcinoma; however, hand foot skin reaction (HFSR) is a dose limiting toxicity of sorafenib that limits its use. HFSR has been associated with sorafenib systemic exposure. The objective of this study was to use modeling and simulation to determine whether using pharmacokinetically guided dosing to achieve a predefined sorafenib target range could reduce the rate of HFSR. Sorafenib steady‐state exposures (area under the concentration curve from 0 to 12‐h [AUC_0–>12 h]) were simulated using published sorafenib pharmacokinetics at either a fixed dosage (90 mg/m²/dose) or a pharmacokinetically guided dose targeting an AUC_0–>12 h between 20 and 55 h µg/ml. Dosages were either rounded to the nearest quarter of a tablet (50 mg) or capsule (10 mg). A Cox proportional hazard model from a previously published study was used to quantify HFSR toxicity. Simulations showed that in‐target studies increased from 50% using fixed doses with tablets to 74% using pharmacokinetically guided dosing with capsules. The power to observe at least 4 of 6 patients in the target range increased from 33% using fixed dosing with tablets to 80% using pharmacokinetically guided with capsules. The expected HFSR toxicity rate decreased from 22% using fixed doses with tablets to 16% using pharmacokinetically guided dosing with capsules. The power to observe less than 6 of 24 studies with HFSR toxicity increased from 51% using fixed dosing with tablets to 88% using pharmacokinetically guided with capsules. Our simulations provide the rationale to use pharmacokinetically guided sorafenib dosing to maintain effective exposures that potentially improve tolerability in pediatric clinical trials.

Pediatric Hepatocellular Carcinoma

PURPOSE

Pediatric hepatocellular carcinoma is rarely seen in childhood. It constitutes approximately 1% of childhood solid organ malignancies. Pediatric hepatocellular carcinoma is the second most common malignant liver tumor after hepatoblastoma in children. In this review, we aimed to review the diagnosis and treatment of pediatric hepatocellular carcinoma in the light of the latest literature.

METHODS

We reviewed the literature in terms of the diagnosis and treatment of pediatric hepatocellular carcinoma.

RESULTS

Hepatocellular carcinoma (HCC) and hepatoblastoma constitute 0.5-1.5% of all childhood malignant tumors. HCC is responsible for 27% of all liver tumors and 4% of all pediatric liver transplantations. While 99.6% of HCC is seen in adults, only 0.4% of it is seen in pediatric patients. Etiological predisposition and biological behavior are different from adults. In a child with cirrhosis or liver disease, HCC should be suspected in the presence of a high level of AFP and an abnormal nodule on ultrasonography. Hepatoblastoma should be considered first in the differential diagnosis.

CONCLUSION

Treatment of pediatric HCC is challenging. Complete surgical resection is essential for the cure. To this end, different neoadjuvant chemotherapy protocols have been designed to convert non-resectable tumors into resectable tumors. For tumors that cannot be resected, liver transplantation for each patient with childhood HCC should be decided individually.

Liver Tumours in Children: The Hepatologist's View

ABSTRACT

Diagnostic and therapeutic innovations have changed the way we now approach liver tumours in children and adolescents. Novel imaging tools, increasing awareness, and surveillance has led to early diagnosis of benign and malignant liver tumours. Multidisciplinary interventions have favourably altered the natural course in some liver tumours. The role of liver transplantation is expanding and has become fully integrated into today's therapeutic algorithms. Transarterial locoregional and ablation therapies have been successful in adults and are being explored in children to facilitate resectability and improve outcome. For the first time, North American, Japanese, and European experts have designed a global trial to optimize management of malignant liver tumours and aim to find signature molecular profiles that will translate to individualised treatment strategies.This article aims to offer an overview of recent advances in our understanding of liver tumours in children. It focuses on the paediatric hepatologist's view and their role in the multidisciplinary management of benign and malignant liver tumours.

Pediatric Primary Hepatic Tumors: Diagnostic Considerations

The liver is the third most common site of abdominal tumors in children. This review article aims to summarize current evidence surrounding identification and diagnosis of primary hepatic tumors in the pediatric population based upon clinical presentation, epidemiology, and risk factors as well as classical imaging, histopathological, and molecular diagnostic findings. Readers will be able to recognize the features and distinguish between benign and malignant hepatic tumors within different age groups.

Sorafenib in pediatric hepatocellular carcinoma from a clinician perspective

Hepatocellular Carcinoma (HCC) is a rare tumor in children and normally carries poor outcomes. The most frequently employed chemotherapy regimen includes cisplatin and doxorubicin (PLADO), but this combination offers limited efficacy. Sorafenib is a multi-tyrosine kinase inhibitor which, following positive studies in adults with HCC, has begun to be introduced in conjunction with PLADO in pediatric oncology with some encouraging results. Based on these findings, the use of sorafenib is become more common in children with unresectable and/or metastatic HCC. The care of patients receiving sorafenib requires appropriate expertise and standardized pediatric guidelines are lacking. An increasing number of children with HCC are expected to receive sorafenib in the years to come. Pediatric oncology clinicians have a key role in identifying side effects early and clinicians caring for children receiving sorafenib need to be familiar with these. This review article provides suitable and practical information on sorafenib for educational development to optimize clinical care and facilitate enhanced patient/parent education. The article addresses specific areas including mechanisms of action, pre-clinical and clinical evidence, dosing and drug administration and toxicities of sorafenib. Clinical research and recommendations for managing sorafenib-related side effects are discussed. Underpinned by research, this article provides pediatric oncology clinicians with the knowledge required to deliver optimal care to children receiving sorafenib.

Population-Based Analysis of Hepatocellular Carcinoma in Children: Identifying Optimal Surgical Treatment

BACKGROUND

Hepatocellular carcinoma (HCC) constitutes 0.5% of childhood malignancies and exhibits poor prognosis. Complete tumor extirpation either by partial liver resection (LR) or liver transplantation (LT) is the only curative treatment. Due to the poor initial outcomes of LT, LR has remained the mainstay of treatment for all but select children fulfilling the Milan criteria (originally designed for adults).

METHODS

We conducted a retrospective cohort study of pediatric HCC patients (younger than 18 years of age) registered in the Surveillance, Epidemiology, and End Results database between 2004 and 2015. Survival analysis was performed by means of Kaplan-Meier methods, 2-sided stratified log-rank tests, and Cox regression models.

RESULTS

Of 127 children with HCC, 46 did not undergo operation (36.2%), 32 underwent LT (25.2%), and 49 underwent LR (38.6%). Using the Kaplan-Meier method, the 5-year cancer-specific survival (CSS) rates for LT and LR were 87% and 63%, respectively. LT exhibited superior CSS vs LR (log-rank, p = 0.007). For T1 stage, LT showed equivalent CSS compared with LR (log-rank, p = 0.23), and for T2 and T3 stage, LT exhibited superior CSS (log-rank, p = 0.047 and p = 0.01, respectively). On multivariable Cox regression analysis, T3/T4 stage (adjusted hazard ratio 13.63; 95% CI, 2.9 to 64.07; p = 0.001), and LR (adjusted hazard ratio 7.51; 95% CI, 2.07 to 27.29; p = 0.002) were found to be independently associated with cancer-specific mortality. Fibrolamellar histology and lymph node status were not found to be associated with mortality.

CONCLUSIONS

Our findings suggest that children diagnosed with nonmetastatic advanced-stage HCC have a favorable prognosis after LT compared with LR. Early inclusion of an LT consultation after the initial diagnosis is warranted, especially in children with unresectable HCC or when complete tumor extirpation with LR is not feasible.

Hepatoblastoma and Pediatric Hepatocellular Carcinoma: An Update

Hepatoblastomas (HBs) and pediatric hepatocellular carcinomas (HCCs) together account for almost 80% of primary malignant liver tumors in children and adolescents/young adults. Children's Hepatic International Collaboration (CHIC), Children's Oncology Group (COG), SociétéInternationale d'Oncologie Pédiatrique (SIOP), and International Childhood Liver Tumors Strategy Group trials have contributed to define prognostic factors and risk stratification in these tumors. The recently proposed histologic International Consensus classification of HB and HCC in children based on retrospective analysis from CHIC cases represents the base to define entities with homogeneous clinicopathologic and molecular features. This review will provide a morphologic guide for the upcoming International Liver Tumor treatment trial (Pediatric Hepatic International Tumour Trial) to be conducted through several continents. There will be an emphasis on molecular features and immunohistochemical markers for the definition of the individual histologic subtypes of HB and to better characterize the group of liver tumors in the provisional category of hepatocellular neoplasm-not otherwise specified. A brief overview of HCC in children will also be provided.

Incidence and long-term outcomes of surgically treated childhood hepatic malignancies in Finland

AIM

To analyse incidence, treatment and outcomes of paediatric liver malignancies in Finland during 1987-2017.

METHODS

Medical records and national cancer registry data of 47 children with liver malignancies were reviewed. Survival was calculated with the Kaplan-Meier method.

RESULTS

During follow-up, liver malignancy incidence remained stable at 1.1:10⁶ . Altogether, 42 patients with hepatoblastoma (n = 24), hepatocellular carcinoma (n = 11) and undifferentiated embryonal sarcoma (n = 7) underwent surgery at median age 4.6 (interquartile range, 2.0-9.6) years and were followed up for 13 (7.0-19) years. Cumulative 5-year survival was 86% for hepatoblastoma, 41% for hepatocellular carcinoma and 67% for undifferentiated embryonal sarcoma. Five-year survival was decreased among hepatoblastoma patients aged ≥ 2.4 years (73% versus 100%, P = .040), with PRETreatment EXTent of disease IV (PRETEXT, 60% vs 100%, P = .004), and with recurrent disease (67% vs 88%, P = .029). Recurrent/residual disease associated with decreased 5-year survival in hepatocellular carcinoma (0% vs 83%, P = .028). Survival was similar among 19 transplanted and 23 resected patients. In total, 14 deaths occurred either for the underlying malignancy (n = 8), adverse effects of chemotherapy (n = 5) or unrelated reasons (n = 1).

CONCLUSION

Outcomes for PRETEXT I-III hepatoblastoma and un-metastasized hepatocellular carcinoma were encouraging. Adverse effects of chemotherapy significantly contributed to mortality.

A Rare Case of Intracardiac Extension of Hepatocellular Carcinoma in a Child

Hepatocellular carcinoma (HCC) is the fifth most common malignancy found in men and ninth most common in women, out of which 72.5% reported cases are from Asia. In children, it accounts for <2% cases worldwide with even rarer incidence of 1.2% involving intracardial extension. However, it presents with a high mortality rate with mean survival ranging from 1 to 4 months. The present case is an extremely rare case of intracardiac extension of HCC in a 3.5-year-old Asian girl with no history of hepatitis B infection presented at an advanced stage of HCC who succumbed within one month of presentation to the hospital.

Integrated analysis of the impact of age on genetic and clinical aspects of hepatocellular carcinoma

Despite the rapid growing and aging of populations worldwide, our knowledge on hepatocellular carcinoma (HCC) is still age-standardized rather than age-specific, with only few studies exploring the topic from a genetic point of view. Here, we analyze clinical and genetic aspects of HCC in patients of different age groups with the major attention directed to children (≤20 y) and elderly groups (≥80 y). A number of significant differences were found in elderly patients compared to children group, including smaller tumor size (P=0.001) and improved survival rates (P=0.002). Differences in gene mutations, copy number variants, and mRNA expressions were identified between the groups, with alteration rates for some genes like AKR1B10 increasing significantly with the age of patients. Immunohistochemistry testing of AKR1B10 showed a significant difference in expression levels at the age of 40 (30.77% high expression rate in patients younger than 40 compared to 51.57% in older patients) (P=0.043). Expression levels also differed between HCC tissues (49.64%) and near-tumor tissues (6.58%) (P<0.001). These findings contribute to the limited data available regarding the age-specific aspects of HCC patients, and support the need to address potential differences in the diagnosis, treatment, and prevention strategies of HCC.

Rare malignant liver tumors in children

Malignant hepatic tumors in children are rare, comprising 1.3% of all pediatric malignancies. Following hepatoblastoma, hepatocellular carcinoma is the second most common. Other malignant hepatic tumors seen in childhood include those of mesenchymal origin including undifferentiated embryonal sarcoma, angiosarcoma, rhabdomyosarcoma and epithelioid hemangioendothelioma, as well as biliary tumors such as cholangiocarcinoma. Diagnosis can be challenging because of their rarity, and the recognition of distinctive imaging features for certain tumors such as epithelioid hemangioendothelioma and biliary rhabdomyosarcoma can focus the differential diagnosis and expedite the diagnostic process. A complete MRI examination with hepatocyte-specific contrast media and diffusion-weighted imaging helps to focus the differential diagnosis, and, although findings are often nonspecific, in some cases typical features on MRI can be helpful in diagnosis. Histopathological analysis is usually required for definitive diagnosis. Hepatic tumors tend to be aggressive, and full staging is imperative to establish disease extent. Significant proportions are not amenable to upfront surgical resection and often require a multimodality approach including neoadjuvant chemotherapy within a multidisciplinary setting. Facilitating complete surgical resection is usually required for better survival. In this review, we emphasize pathology and imaging features for rare liver tumors that are useful in reaching a prompt diagnosis. We also discuss general clinical findings, prognosis and management of these tumors.

Long non-coding RNAs (CASC2 and TUG1) in hepatocellular carcinoma: Clinical significance

BACKGROUND

The biology of hepatocellular carcinoma remains poorly understood. Long non-coding RNAs (lncRNAs) have been confirmed to be key regulators of most cell processes and cancer. The lncRNA cancer susceptibility candidate 2 (CASC2) was originally identified as a downregulated gene in endometrial cancer and acted as a tumor suppressor. The lncRNA taurine up-regulated gene 1 (TUG1) has been shown to play an oncogenic role in various cancers. However, the relative expression of CASC2 and TUG1 in hepatocellular carcinoma (HCC) on top of hepatitis C virus (HCV) and the relationship between both remains unclear. The present study aimed to evaluate both lncRNA CASC2 and TUG1 relative gene expression in whole blood of HCC/HCV patients in relation to HCV and healthy subjects and to relate them to each other and to different clinicopathological factors.

METHODS

The relative expression of CASC2 and TUG1 was estimated by a quantitative reverse transcriptase-polymerase chain reaction in 30 HCC/HCV patients and compared with 20 cases of HCV patients and 20 controls.

RESULTS

CASC2 was downregulated in HCC/HCV patients, whereas TUG1 was overexpressed in relation to HCV and the control group, indicating their antagonistic effect. This suggests their role in the pathogenesis of HCC on top of HCV. Their expression was correlated to Barcelona Clinic Liver Cancer stage and serum alpha-fetoprotein level.

CONCLUSIONS

CASC2 and TUG1 could be new potential biomarkers with a valid non-invasive technique.

Predisposing Conditions to Pediatric Hepatocellular Carcinoma and Association With Outcomes: Single-center Experience

OBJECTIVES

Hepatocellular carcinoma (HCC) has been linked to chronic viral or metabolic liver disease and other conditions. The characteristics of children with HCC have not been fully elucidated and outcomes in children with predisposing liver disease are not well defined.

METHODS

Patients ≤21 years old with HCC managed at our institution and through external consultation between 1996 and 2016 were included. Demographics, clinical history, and pathology were tabulated. Fisher exact test and Wilcoxon test were employed for subgroup comparison, and survival differences were evaluated by Kaplan-Meier method.

RESULTS

Sixty-one cases of HCC were identified. Seven of 16 patients (44%) at our institution and 18 of 45 consult patients (40%) had a predisposing condition: cryptogenic cirrhosis/steatosis (9), genetic (7), biliary pathology (4), viral hepatitis (1), and other (4). Thirteen of 27 patients with de novo HCC had fibrolamellar HCC. Clinical characteristics were grouped by presence or absence of predisposing conditions: age at diagnosis (7.2 vs 10.2 years, P < 0.05), metastatic disease at presentation (15% vs 44%, P = n.s), and tumor size >4 cm (20% vs 100%, P < 0.05). In patients treated at our institution, 5 of 7 with predisposing conditions received liver transplant and achieved complete remission, whereas only 3 of 9 patients with de novo HCC received curative surgery and this group had decreased median overall survival (P < 0.05).

CONCLUSIONS

The majority of children with HCC did not have predisposing liver or associated disease. These patients were diagnosed later with more advanced stage disease and had significantly decreased overall survival.

Pediatric Liver Tumors

Although liver tumors are rare in the pediatric population, they are common in the setting of children with specific risk factors requiring increased awareness and, in some instances, screening. The evaluation of a liver mass in children is largely driven by the age at diagnosis, the presence of any medical comorbidities, and initial testing with alpha fetoprotein and imaging. Specific guidelines for the management of different tumors have been implemented in recent years such that a multidisciplinary approach is ideal and care should be provided by centers with experience in their management.

Reactive Ductules Are Associated With Angiogenesis and Tumor Cell Proliferation in Pediatric Liver Cancer

While reactive ductules (RDs) have been observed in viral hepatitis, biliary atresia, nonalcoholic fatty liver disease, and adult hepatocellular carcinoma (HCC), RDs in pediatric liver cancer remain uncharacterized. This study investigated the relationship of RDs with angiogenic paracrine factors, the extent of angiogenesis, and tumor cell proliferation in pediatric hepatoblastoma (HBL)/HCC livers. We quantified the extent of RDs and their expression of paracrine factors that include vascular endothelial growth factor (VEGF), vascular endothelial growth factor D (VEGFD), platelet‐derived growth factor C, and angiopoietin 1 (ANGPT1). In addition, we performed immunohistochemical detection of the endothelial marker clusters of differentiation (CD)34 and the proliferation marker Ki67 followed by correlation analyses. In HBL, we found the percentage of RDs with Ki67 expression (% Ki67+ RDs) significantly correlated with intratumoral Ki67+ areas (r = 0.5138, P = 0.0349) and % ANGPT1+ RDs positively correlated with % Ki67+ RDs (r = 0.5851, P = 0.0136). In HCC, the high ANGPT1+ RDs group (i.e., cases with % ANGPT1+ RDs ≥50) exhibited high intratumoral Ki67+ areas compared to the low ANGPT1+ RDs group. In the combined HBL and HCC liver tumor group, there was a positive association between % platelet‐derived growth factor C+ RDs and intratumoral Ki67+ areas (r = 0.4712, P = 0.0099) and the high VEGFD+ RDs group (≥50%) exhibited a high number of peritumoral CD34+ vessels compared to the low VEGFD+ RDs group. Conclusion: Paracrine factor‐expressing RDs are associated with angiogenesis and proliferation of pediatric liver tumors.

Pediatric hepatocellular carcinoma

Pediatric hepatocellular carcinoma (HCC) is the second common malignant liver tumor in children after hepatoblastoma. It differs from the adult HCC in the etiological predisposition, biological behavior and lower frequency of cirrhosis. Perinatally acquired hepatitis-B virus, hepatorenal tyrosinemia, progressive familial intrahepatic cholestasis, glycogen storage disease, Alagille’s syndrome and congenital portosystemic shunts are important predisposing factors. Majority of children (87%) are older than 5 years of age. Following mass immunization against hepatitis-B, there has been a drastic fall in the incidence of new cases of pediatric HCC in the Asia-Pacific region. Management is targeted on complete surgical removal either by resection or liver transplantation. There is a trend towards improving survival of children transplanted for HCC beyond Milan criteria. Chemotherapeutic regimens do not offer good results but may be helpful for down-staging of advanced HCC. Surveillance of children with chronic liver diseases with ultrasound and alpha-fetoprotein may be helpful in timely detection, intervention and overall improvement in outcome of HCC.

Hepatocellular carcinoma in children: hepatic resection and liver transplantation

Hepatocellular carcinoma (HCC) is a rare malignancy in children and at the time of diagnosis up to 80% of pediatric HCC are unresectable due to large and multiple lesions. The majority of pediatric HCC occurs on a background of normal liver, and consequently the absence of concomitant chronic liver disease generally allows tolerating pre- and post-operative chemotherapy. Based on the large experiences of adult HCC and pediatric hepatoblastoma, in the last years a multidisciplinary aggressive treatment composed of surgical resection and chemotherapy (based on cisplatin and doxorubicin) has been proposed, improving patient outcomes and recurrence rate in children with HCC. However, the overall survival rate in children with HCC is not satisfactory yet; while the 5-year survival rate may achieve up to 70-80% in non-metastatic resectable HCC, it remains <20% in children with unresectable HCC. The mainstay of the pediatric HCC therapeutic strategy is the radical tumor resection, weather by hepatic resection or liver transplantation, nevertheless the best surgical approaches as well as the optimal neoadjuvant and adjuvant treatment are still under debate. Different strategies have been explored to convert unresectable HCC into resectable tumors by extending criteria for surgical treatment and/or associating multi-modal treatments, such as systemic and local-regional therapy, but universal recommendation needs to be defined yet. The purpose of this review is to outline the role of different surgical approaches, including hepatic resection and liver transplantation, in pediatric HCC with or without underlying chronic liver disease.

Primary Liver Cancers-Part 1: Histopathology, Differential Diagnoses, and Risk Stratification

Hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC) are the 2 most common primary malignant liver tumors, with hepatocellular and bile ductular differentiation, respectively. This article reviews the key histopathological findings of these 2 primary liver cancers and includes a review of the role of ancillary testing for differential diagnosis, risk stratification according to the American Joint Committee on Cancer (AJCC) staging recommendation, and a review of precancerous lesions. A literature review was conducted to identify articles with information relevant to precancerous precursors, current histopathological classification, ancillary testing, and risk stratification of primary malignant liver tumors. The histomorphology of normal liver, preinvasive precursors, primary malignancies, and morphological variants, and the utilization of ancillary tests for the pathological diagnosis are described. Dysplastic nodules are the preinvasive precursors of HCC, and intraductal papillary neoplasms of bile ducts and biliary intraepithelial neoplasia are the preinvasive precursors of CC. Benign liver nodules including focal nodular hyperplasia and adenomas are included in this review, since some forms of adenomas progress to HCC and often they have to be differentiated from well-differentiated HCC. A number of morphological variants of HCC have been described in the literature, and it is necessary to be aware of them in order to render the correct diagnosis. Risk stratification is still dependent on the AJCC staging system. The diagnosis of primary liver carcinomas is usually straightforward. Application of the appropriate ancillary studies aids in the differential diagnosis of difficult cases. The understanding of the carcinogenesis of these malignancies has improved with the standardization of the pathological classification of preinvasive precursors and studies of the molecular pathogenesis. Risk stratification still depends on pathological staging.

Transarterial chemoembolization in children to treat unresectable hepatocellular carcinoma

Children with unresectable HCC have a dismal prognosis and few approved treatment options. TACE is an effective treatment option for adults with HCC, but experience in children is very limited. Retrospective analysis was performed of 8 patients aged 4-17 years (4 male, mean 12.5 years) who underwent TACE for unresectable HCC. Response to TACE was evaluated by change in AFP, RECIST and tumor volume, PRETEXT, and transplantation eligibility by UCSF and Milan criteria. Post-procedure mean follow-up was 8.2 years. Mean overall change in tumor volume for the 8 patients was 51%. Percent change in AFP ranged from a decrease of 100% to an increase of 89.3%, with a mean change of -49.6%. Two patients did not undergo resection or transplantation and died of progressive disease. Six patients underwent orthotopic liver transplantation with mean first TACE-to-transplant interval of 141 days (range 11-514). Following transplantation, 5 patients were alive at the end of the follow-up period and one died of recurrent disease. Based on our initial experience, TACE for children with unresectable HCC appears to be a safe and effective method for managing hepatic tumor burden and for downstaging and bridging to liver transplantation.

Role of interventional radiology in managing pediatric liver tumors : Part 1: Endovascular interventions

Primary liver malignancies are rare in children. Hepatoblastoma and hepatocellular carcinoma (HCC) together represent the overwhelming majority of cases. Overall survival of hepatoblastoma approaches 80% with multimodal treatment approaches that include chemotherapy, surgery and transplantation. However, there remains a subset of children with hepatoblastoma in whom resection or transplantation is not possible. The 5-year survival for children diagnosed with HCC is less than 30% and remains a significant therapeutic challenge. The poor outcomes for children with primary liver tumors motivate investigation of new therapeutic alternatives. Interventional oncology offers a broad scope of percutaneous and transcatheter endovascular cancer therapies that might provide clinical benefits. Minimally invasive approaches are distinct from medical, surgical and radiation oncologic treatments, and in adults these approaches have been established as the fourth pillar of cancer care. Transarterial chemoembolization is a minimally invasive locoregional treatment option performed by interventional radiologists with level-I evidence as standard of care in adults with advanced liver malignancy; transarterial chemoembolization in adults has served to prolong disease-free progression, downstage and bridge patients for surgical and transplant interventions, and improve overall survival. However, while several groups have reported that transarterial chemoembolization is feasible in children, the published experience is limited primarily to small retrospective case series. The lack of prospective trial evidence has in part limited the utilization of transarterial chemoembolization in the pediatric patient population. The purpose of this article is to provide an overview of the role of interventional radiology in the diagnosis and endovascular management of hepatic malignancies in children.

Survival of children after liver transplantation for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) in childhood differs from adult HCC because it is often associated with inherited liver disease. It is, however, unclear whether liver transplantation (LT) for HCC in childhood with or without associated inherited disease has a comparable outcome to adult HCC. On the basis of data from the European Liver Transplant Registry (ELTR), we aimed to investigate if there are differences in patient and graft survival after LT for HCC between children and adults and between patients with underlying inherited versus noninherited liver disease, respectively. We included all 175 children who underwent LT for HCC and were enrolled in ELTR between 1985 and 2012. Of these, 38 had an associated inherited liver disease. Adult HCC patients with (n = 79) and without (n = 316, matched by age, sex, and LT date) inherited liver disease served as an adult comparison population. We used multivariable piecewise Cox regression models with shared frailty terms (for LT center) to compare patient and graft survival between the different HCC groups. Survival analyses demonstrated a superior longterm survival of children with inherited liver disease when compared with children with HCC without inherited liver disease (hazard ratio [HR], 0.29; 95% CI, 0.10-0.90; P = 0.03) and adults with HCC with inherited liver disease (HR, 0.27; 95% CI, 0.06-1.25; P = 0.09). There was no survival difference between adults with and without inherited disease (HR, 1.05; 95% CI, 0.66-1.66; P = 0.84). In conclusion, the potential survival advantage of children with an HCC based on inherited disease should be acknowledged when considering transplantation and prioritization for these patients. Further prospective studies accounting for tumor size and extension at LT are necessary to fully interpret our findings. Liver Transplantation 24 246-255 2018 AASLD.

Hepatocellular malignant neoplasm, NOS: a clinicopathological study of 11 cases from a single institution

AIMS

The primary aim of this study is to characterize hepatocellular malignant neoplasm, NOS (HEMNOS), a new provisional entity describing a subset of paediatric hepatocellular tumours, which have histological features of neither typical hepatoblastoma (HB) nor hepatocellular carcinoma (HCC).

METHODS AND RESULTS

The clinicopathological features of 11 patients with HEMNOS were analysed retrospectively. The median age and serum alpha-fetoprotein level at diagnosis was 7 years and 182 000 ng/ml, respectively. Ten patients presented with pretreatment extent of disease (PRETEXT) stages III/IV multifocal tumours, eight with major vascular involvement, three with lung metastases and three with extrahepatic extension. The original pathology diagnoses were: HB in seven patients, HCC in two and HEMNOS in two. Our pathology review of pre-chemotherapy specimens showed that six tumours had equivocal/overlapping histological features of HB and HCC, four had predominant HB histology along with focal HCC-like histology and one had HB histology. Seven of nine post-chemotherapy resection specimens showed predominant HCC-like histology. Beta-catenin, glypican 3 and spalt-like transcription factor 4 immunostaining showed that all the tumours had a mixed HB/HCC immunophenotype. Telomerase reverse transcriptase immunostaining showed nuclear staining in nine of the 11 tumours. All patients received chemotherapy and achieved gross total primary tumour resection. Nine of the 11 patients were treated with established HB chemotherapy regimens. After a median follow-up of 6.1 years (range: 1.2-11.8 years), all patients were in remission.

CONCLUSIONS

HEMNOS is a subtype of HB with focal HCC-like histology, a high-risk clinical profile but favourable outcome following chemotherapy and complete tumour resection.

Management of pediatric hepatocellular carcinoma: A multimodal approach

HCC is rare in the pediatric population, but is the second most common liver malignancy in children. Survival rates for primary unresectable HCC have been dismal. The objective of this study was to describe our experience with a multimodal approach for the management of unresectable HCC in two adolescent patients and to review the literature. Both patients are currently alive with no recurrence at 51 and 29 months post-transplant. Multimodality treatment involving chemotherapy with doxorubicin, cisplatin, and sorafenib; TACE; timely liver transplantation; and post-transplant therapy with sorafenib and mTOR inhibitors may help improve outcomes and prolong survival in pediatric patients with unresectable HCC.

Hepatic Malignancy in an Infant with Wolf-Hirschhorn Syndrome

INTRODUCTION

Wolf-Hirschhorn syndrome (WHS) is a contiguous gene syndrome involving deletions of the chromosome 4p16 region associated with growth failure, characteristic craniofacial abnormalities, cardiac defects, and seizures.

CASE REPORT

This report describes a six-month-old girl with WHS with growth failure and typical craniofacial features who died of complex congenital heart disease. Genetic studies revealed a 9.8 Mb chromosome 4p-terminal deletion. At autopsy, the liver was grossly unremarkable. Routine sampling and histologic examination revealed two hepatocellular nodular lesions with expanded cell plates and mild cytologic atypia. Immunohistochemical staining revealed these nodules were positive for glutamine synthetase and glypican 3, with increased Ki-67 signaling and diffuse CD34 expression in sinusoidal endothelium. These findings are consistent with hepatoblastoma or hepatocellular carcinoma.

CONCLUSIONS

A possible association between WHS and hepatic malignancy may be an important consideration in the care and management of WHS patients.

Hepatocellular Carcinoma in Children and Adolescents: Clinical Characteristics and Treatment

BACKGROUND

Hepatocellular carcinoma (HCC) occurs rarely in children and adolescents (C&A), and its clinical characteristics, prognostic factors, and treatment were rarely explored.

METHODS

This retrospective study focused on 65 HCC patients aged ≤20 years from August 1994 to August 2012. Cox regression models and Kaplan-Meier curves were used to investigate prognostic factors and compare overall survival (OS), respectively.

RESULTS

We found 61.5% of patients to have multiple tumors, 30.8% to have portal vein tumor thrombus, and 16.9% to have distant metastasis. Diameter of tumors was 10.2 ± 4.1 cm. OS at 5 years was 15.8%. Multivariate analyses showed initial treatment (P < 0.001) to be a predictor for OS. For moderate-stage HCC, the median OS of patients who underwent resection was longer than that of patients who underwent transarterial chemoembolization (TACE) or supportive treatment (ST) (P < 0.001). For advanced-stage HCC, the median OS of patients who underwent TACE was longer than that of patients who underwent ST (P = 0.045).

CONCLUSIONS

HCC in C&A tends to be more advanced than that in adults, and resection remains the mainstay of treatment for those patients. Moreover, compared with ST, TACE may benefit C&A with moderate- and advanced-stage HCC, which needs further study.

Pediatric hepatocellular carcinoma in a developing country: Is the etiology changing?

HCC is the second most common malignant liver tumor of childhood. It typically affects children with a median age of 10-14 yr on background hepatitis B-related liver disease and is often metastatic or locally advanced at diagnosis. Children below the age of five yr typically constitute <10% of all children with HCC. In these children, it occurs on a background of congenital or metabolic liver disease. The records of all children with HCC who presented to our department over a six-yr study period were reviewed. Twelve patients with a median age of 5.9 yr (range 1.6-15.4) were diagnosed to have HCC. All patients underwent liver transplantation, and none were resected. Eleven patients had background congenital or metabolic liver disease. All five of those with hereditary tyrosinemia type 1 who presented to us were found to have HCC. No patient had hepatitis B-related liver (HBV) disease. Eight (66.7%) patients had incidentally discovered HCC on examination of the explant. Incidentally discovered HCC were smaller, well differentiated, and did not show microvascular invasion compared to those diagnosed preoperatively. There was no recurrence with a median follow-up of five months. The patient demographic for pediatric HCC is changing probably as a consequence of successful immunization against HBV. Younger patients with congenital and metabolic liver disease in whom liver transplantation is the ideal treatment are likely to constitute an ever-increasing proportion of patients with pediatric HCC as HBV disease is controlled or eradicated.

YAP Subcellular Localization and Hippo Pathway Transcriptome Analysis in Pediatric Hepatocellular Carcinoma

Pediatric hepatocellular carcinoma (HCC) is a rare tumor which is associated with an extremely high mortality rate due to lack of effective chemotherapy. Recently, the Hippo pathway and its transcriptional co-activator Yes-associated protein (YAP) have been shown to play a role in hepatocyte proliferation and development of HCC in animal models. Therefore, we sought to examine the activity of YAP and the expression of Hippo pathway components in tumor and non-neoplastic liver tissue from 7 pediatric patients with moderately differentiated HCC. None of the patients had underlying cirrhosis or viral hepatitis, which is commonly seen in adults with HCC. This highlights a major difference in the pathogenesis of HCC between children and adults. We found a statistically significant increase in YAP nuclear localization in 100% of tumors. YAP target gene (CCNE1, CTGF, Cyr61) mRNA expression was also increased in the tumors that had the most significant increase in YAP nuclear localization. Based on Ki67 co-localization studies YAP nuclear localization was not simply a marker of proliferation. Our results demonstrate a clear increase in YAP activity in moderately differentiated pediatric HCC, providing evidence that it may play an important role in tumor survival and propagation.

Fibrolamellar Hepatocellular Carcinoma: Mechanistic Distinction From Adult Hepatocellular Carcinoma

Fibrolamellar hepatocellular carcinoma (FL-HCC) has historically been classified as a rare subtype of HCC. However, unlike "classic" HCC, it occurs in children and young adults without underlying liver disease. The recent discovery of a deletion mutation in all FL-HCCs represented a major advancement in understanding the pathogenesis of this disease. This deletion results in the fusion of the genes encoding a heat shock protein (DNAJB1) and the catalytic subunit of protein kinase A (PKA, PRKACA), and overexpression of PRKACA and enhanced cAMP-dependent PKA activity. This review summarizes recent advancements in FL-HCC pathogenesis and characteristics of the HSP40-PKA C protein.

Pediatric papillary thyroid carcinoma: outcomes and survival predictors in 2504 surgical patients

OBJECTIVE

To evaluate outcomes and predictors of survival of pediatric thyroid carcinoma, specifically papillary thyroid carcinoma.

METHODS

SEER was searched for surgical pediatric cases (≤20 years old) of papillary thyroid carcinoma diagnosed between 1973 and 2011. Demographics, clinical characteristics, and survival outcomes were analyzed using standard statistical methods. All papillary types, including follicular variant, were included.

RESULTS

A total of 2504 cases were identified. Overall incidence was 0.483/100,000 persons per year with a significant annual percent change (APC) in occurrence of 2.07 % from baseline (P < 0.05). Mean age at diagnosis was 16 years and highest incidence was found in white, female patients ages 15-19. Patients with tumor sizes <1 cm more likely received lobectomies/isthmusectomies versus subtotal/total thyroidectomies [OR = 3.03 (2.12, 4.32); P < 0.001]. Patients with tumors ≥1 cm and lymph node-positive statuses [OR = 99.0 (12.5, 783); P < 0.001] more likely underwent subtotal/total thyroidectomy compared to lobectomy/isthmusectomy. Tumors ≥1 cm were more likely lymph node-positive [OR = 39.4 (16.6, 93.7); p < 0.001]. Mortality did not differ between procedures. Mean survival was 38.6 years and higher in those with regional disease. Disease-specific 30-year survival ranged from 99 to 100 %, regardless of tumor size or procedure. Lymph node sampling did not affect survival.

CONCLUSIONS

The incidence of pediatric papillary thyroid cancer is increasing. Females have a higher incidence, but similar survival to males. Tumors ≥1 cm were likely to be lymph node-positive. Although tumors ≥1 cm were more likely to be resected by subtotal/total thyroidectomy, survival was high and did not differ based on procedure.

Hepatocellular Carcinoma, Fibrolamellar Variant: Diagnostic Pathologic Criteria and Molecular Pathology Update. A Primer

Fibrolamellar hepatocellular carcinoma (FL-HCC) is generally a fairly rare event in routine pathology practice. This variant of hepatocellular carcinoma (HCC) is peculiarly intriguing and,in addition, poorly understood. Young people or children are often the target individuals with this type of cancer. Previously, I highlighted some pathology aspects of FL-HCC, but in this review, the distinctive clinico-pathologic features of FL-HCC and the diagnostic pathologic criteria of FL-HCC are fractionally reviewed and expanded upon. Further, molecular genetics update data with reference to this specific tumor are particularly highlighted as a primer for general pathologists and pediatric histopathologists. FL-HCC may present with metastases, and regional lymph nodes may be sites of metastatic spread. However, peritoneal and pulmonary metastatic foci have also been reported. To the best of our knowledge, FL-HCC was initially considered having an indolent course, but survival outcomes have recently been updated reconsidering the prognosis of this tumor. Patients seem to respond well to surgical resection, but recurrences are common. Thus, alternative therapies, such as chemotherapy and radiation, are ongoing. Overall, it seems that this aspect has not been well-studied for this variant of HCC and should be considered as target for future clinical trials. Remarkably, FL-HCC data seem to point to a liver neoplasm of uncertain origin and unveiled outcome. A functional chimeric transcript incorporating DNAJB1 and PRKACA was recently added to FL-HCC. This sensational result may give remarkable insights into the understanding of this rare disease and potentially provide the basis for its specific diagnostic marker. Detection of DNAJB1-PRKACA seems to be, indeed, a very sensitive and specific finding in supporting the diagnosis of FL-HCC. In a quite diffuse opinion, prognosis of this tumor should be reconsidered following the potentially mandatory application of new molecular biological tools.

Hepatocellular Carcinoma in the Pediatric Population: A Population Based Clinical Outcomes Study Involving 257 Patients from the Surveillance, Epidemiology, and End Result (SEER) Database (1973-2011)

Introduction. Hepatocellular carcinoma (HCC) is a rare pediatric cancer accounting for 0.5% of all pediatric malignancies. This study examines a large cohort of HCC patients in an effort to define the factors impacting clinical outcomes in pediatric HCC patients compared to adults. Methods. Demographic and clinical data on 63,771 HCC patients (257 pediatric patients ≤ 19 and 63,514 adult patients age ≥ 20) were abstracted from the SEER database (1973–2011). Results. HCC was more common among males (59.5% pediatric and 75.1% adults) and Caucasians (50.4% and 50.5%), p < 0.05. Children more often presented with fibrolamellar variant HCC (24.1% versus 0.3%, p = 0.71) and advanced HCC, including distant disease (33.1% versus 20.8%, p < 0.001), and tumors > 4 cm in size (79.6% versus 62.0%, p = 0.02). Pediatric HCC patients undergoing surgery (13.107 versus 8.324 years, p < 0.001) had longer survival than adult HCC patients. Overall mortality was lower (65.8% versus 82.0%, p < 0.001) in the pediatric HCC group. Conclusion. HCC is a rare pediatric malignancy that presents most often as an advanced tumor, >4 cm in Caucasian males. Children with HCC achieve significantly longer mean overall survival compared to adults with HCC, primarily attributable to the more favorable fibrolamellar histologic variant, and more aggressive surgical intervention, which significantly improves survival.