The importance of age as prognostic factor for the outcome of patients with hepatoblastoma: Analysis from the Children's Hepatic tumors International Collaboration (CHIC) database

Successful treatment of young childhood standard-risk hepatoblastoma with cisplatin monotherapy using a central review system

BACKGROUND

The JPLT3-S (Japanese Study Group for Pediatric Liver Tumors-3) study, conducted cisplatin (CDDP) monotherapy for young children (<3 years old) with standard-risk hepatoblastoma (HB) using a central review system in Japan. In the previous JPLT2 study, cases with resectable tumors without any annotation factors in the PRETEXT (PRETreatment EXTent of disease) classification (standard-risk HB) showed favorable outcomes with treatment consisting of CDDP and pirarubicin, but showed toxicities and late complications. In the JPLT3-S trial, a less intense regimen consisting of CDDP alone was evaluated.

METHODS

Patients who were less than 3 years of age and with PRETEXT I, II, or III HB without any annotation factors (e.g., E1, E1a, E2, E2a, H1, N1, P2, P2a, V3, and V3a) were eligible for inclusion in this study. In this trial, the central radiological and pathological features of all patients were reviewed. The primary outcome was the 3-year progression-free survival (PFS).

RESULTS

A total of 38 patients (23 female) were included. The median patient age was 12 months (range: 2-34). Two patients discontinued treatment because of progressive disease, and five patients discontinued treatment for other reasons. The 3-year PFS rate was 93.9% (95% confidence interval [CI]: 86.4%-100%). All 38 patients survived (follow-up period 38-98 months), and the OS rate was 100% (CI: 100). Eighteen of the 38 patients (47.4%) experienced ototoxicity as a late complication.

CONCLUSION

CDDP monotherapy regimen is feasible in young patients with localized HB, as classified by a central review.

IMPDH2 suppression impedes cell proliferation by instigating cell cycle arrest and stimulates apoptosis in pediatric hepatoblastoma

BACKGROUND

Hepatoblastoma (HB) is the most common pediatric liver tumor, presenting significant therapeutic challenges due to its high rates of recurrence and metastasis. While Inosine Monophosphate Dehydrogenase 2(IMPDH2) has been associated with cancer progression, its specific role and clinical implications in HB have not been fully elucidated.

METHODS

This study utilized Quantitative Real-Time Polymerase Chain Reaction (qRT-PCR) and Tissue Microarray (TMA) for validation. Following this, IMPDH2 was suppressed, and a series of in vitro assays were conducted. Flow cytometry was employed to assess apoptosis and cell cycle arrest. Additionally, the study explored the synergistic therapeutic effects of mycophenolate mofetil (MMF) and doxorubicin (DOX) on HB cell lines.

RESULTS

The study identified a marked overexpression of IMPDH2 in HB tissues, which was strongly correlated with reduced Overall Survival (OS) and Event-Free Survival (EFS). IMPDH2 upregulation was also found to be associated with key clinical-pathological features, including pre-chemotherapy alpha-fetoprotein (AFP) levels, presence of preoperative metastasis, and the pre-treatment extent of tumor (PRETEXT) staging system. Knockdown of IMPDH2 significantly inhibited HB cell proliferation and tumorigenicity, inducing cell cycle arrest at the G0/G1 phase. Notably, the combination of MMF, identified as a specific IMPDH2 inhibitor, with DOX, substantially enhanced the therapeutic response.

CONCLUSION

The overexpression of IMPDH2 was closely linked to adverse outcomes in HB patients and appeared to accelerate cell cycle progression. These findings suggest that IMPDH2 may serve as a valuable prognostic indicator and a potential therapeutic target for HB.

IMPACT

The present study unveiled a significant overexpression of inosine monophosphate dehydrogenase 2 (IMPDH2) in hepatoblastoma (HB) tissues, particularly in association with metastasis and recurrence of the disease. The pronounced upregulation of IMPDH2 was found to be intimately correlated with adverse outcomes in HB patients. This overexpression appears to accelerate the progression of the cell cycle, suggesting that IMPDH2 may serve as a promising candidate for both a prognostic marker and a therapeutic target in the context of HB.

Impact of treatment on the prognosis of childhood in hepatoblastoma: A SEER based analysis

Background

The prognosis of patients with hepatoblastoma has been unsatisfactory. This study analyzed the effects of different treatment methods on cancer-specific survival (CSS) in children with hepatoblastoma.

Method

From 2000 to 2018, patients with hepatoblastoma were included in the Surveillance, Epidemiology, and End Results (SEER) database. CSS was estimated using the Kaplan-Meier method. Cox regression analysis assessed prognostic factors. The predictive models were validated using the concordance index (C-index), calibration curve and receiver operating characteristic (ROC) curve.

Result

Of the 785 included patients, 730 (93.0 %) underwent chemotherapy, 516 (65.7 %) underwent liver tumour resection and 129 (16.4 %) underwent liver transplantation. Both chemotherapy and surgery could significantly improve the CSS rate (all p < 0.001). However, there was no difference in CSS rate between the two surgical methods (liver tumour resection and liver transplantation) (p = 0.613). Further subgroup analysis revealed that children who underwent liver tumour resection or liver transplantation based on chemotherapy (all p > 0.05) had a similar prognosis. Multivariate analysis revealed that age (p = 0.003), race (p = 0.001), operative method (p < 0.001), chemotherapy (p < 0.001), distant metastasis (p < 0.001) and tumour size (p < 0.001) were independent factors related to CSS. The C-index of the new nomogram was 0.759, and its consistency was good. The ROC curves verified that the nomogram had a better prediction ability for 1-, 3- and 5-year CSS rates.

Conclusion

In children with hepatoblastoma, there was no statistically significant difference in CSS between chemotherapy combined with liver transplantation and liver tumour resection. The nomogram we constructed demonstrated satisfactory CSS prediction ability.

Surgical management of liver tumors

Two percent of pediatric malignancies arise primarily in the liver; roughly 60% of these cancers are hepatoblastoma (HB). Despite the rarity of these cases, international collaborative efforts have led to the consistent histological classification and staging systems, which facilitate ongoing clinical trials. Other primary liver malignancies seen in children include hepatocellular carcinoma (HCC) with or without underlying liver disease, fibrolamellar carcinoma (FLC), undifferentiated embryonal sarcoma of the liver (UESL), and hepatocellular neoplasm not otherwise specified (HCN-NOS). This review describes principles of surgical management of malignant pediatric primary liver tumors, within the context of comprehensive multidisciplinary care.

A multicenter prospective study on the management of hepatoblastoma in children: a report from the Chinese Children's Cancer Group

BACKGROUND

This study aimed to identify survival risk factors in Chinese children with hepatoblastoma (HB) and assess the effectiveness of the new treatment protocol proposed by the Chinese Children's Cancer Group (CCCG) in 2016.

METHODS

A multicenter, prospective study that included 399 patients with HB from January 2015 to June 2020 was conducted. Patient demographics, treatment protocols, and other related information were collected. Cox regression models and Kaplan-Meier curve methods were used.

RESULTS

The 4-year event-free survival (EFS) and overall survival (OS) were 76.9 and 93.5%, respectively. The 4-year EFS rates for the very-low-risk, low-risk, intermediate-risk, and high-risk groups were 100%, 91.6%, 81.7%, and 51.0%, respectively. The 4-year OS was 100%, 97.3%, 94.4%, and 86.8%, respectively. Cox regression analysis found that age, tumor rupture (R +), and extrahepatic tumor extension (E +) were independent prognostic factors. A total of 299 patients had complete remission, and 19 relapsed. Patients with declining alpha-fetoprotein (AFP) > 75% after the first two cycles of neoadjuvant chemotherapy had a better EFS and OS than those ≤ 75%.

CONCLUSIONS

The survival outcome of HB children has dramatically improved since the implementation of CCCG-HB-2016 therapy. Age ≥ 8 years, R + , and E + were independent risk factors for prognosis. Patients with a declining AFP > 75% after the first two cycles of neoadjuvant chemotherapy had better EFS and OS.

Predicting response of hepatoblastoma primary lesions to neoadjuvant chemotherapy through contrast-enhanced computed tomography radiomics

OBJECTIVE

To investigate the clinical value of contrast-enhanced computed tomography (CECT) radiomics for predicting the response of primary lesions to neoadjuvant chemotherapy in hepatoblastoma.

METHODS

Clinical and CECT imaging data were retrospectively collected from 116 children with hepatoblastoma who received neoadjuvant chemotherapy. Tumor response was assessed according to the Response Evaluation Criteria in Solid Tumors (RECIST). Subsequently, they were randomly stratified into a training cohort and a test cohort in a 7:3 ratio. The clinical model was constructed using univariate and multivariate logistic regression, while the radiomics model was developed based on selected radiomics features employing the support vector machine algorithm. The combined clinical-radiomics model incorporated both clinical and radiomics features.

RESULTS

The area under the curve (AUC) for the clinical, radiomics, and combined models was 0.704 (95% CI: 0.563-0.845), 0.830 (95% CI: 0.704-0.959), and 0.874 (95% CI: 0.768-0.981) in the training cohort, respectively. In the validation cohort, the combined model achieved the highest mean AUC of 0.830 (95% CI 0.616-0.999), with a sensitivity, specificity, accuracy, precision, and f1 score of 72.0%, 81.1%, 78.5%, 57.2%, and 63.5%, respectively.

CONCLUSION

CECT radiomics has the potential to predict primary lesion response to neoadjuvant chemotherapy in hepatoblastoma.

Critical elements of pediatric liver cancer surgery

The appropriate management of pediatric liver malignancies, primarily hepatoblastoma and hepatocellular carcinoma, requires an in depth understanding of contemporary preoperative risk stratification, experience with advanced hepatobiliary surgery, and a good relationship with one's local or regional liver transplant center. While chemotherapy regimens have become more effective, operative indications more well-defined, and overall survival improved, the complexity of liver surgery in small children provides ample opportunity for protocol violation, inadequate resection, and iatrogenic morbidity. These guidelines represent the distillation of contemporary literature and expert opinion as a means to provide a framework for preoperative planning and intraoperative decision-making for the pediatric surgeon.

Surgical Management and Outcomes of Patients with Multifocal Hepatoblastoma

OBJECTIVE

To compare the outcomes of patients with multifocal hepatoblastoma (HB) treated at our institution with either orthotopic liver transplant (OLTx) or hepatic resection to determine outcomes and risk factors for recurrence.

BACKGROUND

Multifocality in HB has been shown to be a significant prognostic factor for recurrence and worse outcome. The surgical management of this type of disease is complex and primarily involves OLTx to avoid leaving behind microscopic foci of disease in the remnant liver.

METHODS

We performed a retrospective chart review on all patients <18 years of age with multifocal HB treated at our institution between 2000 and 2021. Patient demographics, operative procedure, post-operative course, pathological data, laboratory values, short- and long-term outcomes were analyzed.

RESULTS

A total of 41 patients were identified as having complete radiologic and pathologic inclusion criteria. Twenty-three (56.1%) underwent OLTx and 18 (43.9%) underwent partial hepatectomy. Median length of follow-up across all patients was 3.1 years (IQR 1.1-6.6 years). Cohorts were similar in rates of PRETEXT designation status identified on standardized imaging re-review (p = .22). Three-year overall survival (OS) estimate was 76.8% (95% CI: 60.0%-87.3%). There was no difference in rates of recurrence or overall survival in patients who underwent either resection or OLTx (p = .54 and p = .92 respectively). Older patients (>72 months), patients with a positive porta hepatis margin, and patients with associated tumor thrombus experienced worse recurrence rates and survival. Histopathology demonstrating pleomorphic features independently associated with worse rates of recurrence.

CONCLUSIONS

Through proper patient selection, multifocal HB was adequately treated with either partial hepatectomy or OLTx with comparable outcome results. HB with pleomorphic features, increased patient age at diagnosis, involved porta hepatis margin on pathology, and the presence of associated tumor thrombus may be associated with worse outcomes regardless of the local control surgery offered.

LEVEL OF EVIDENCE

III.

Children's Oncology Group's 2023 blueprint for research: Liver tumors

Liver tumors account for approximately 1%-2% of all pediatric malignancies, with the two most common tumors being hepatoblastoma (HB) and hepatocellular carcinoma (HCC). Previous Children's Oncology Group studies have meaningfully contributed to the current understanding of disease pathophysiology and treatment, laying groundwork for the ongoing prospective international study of both HB and HCC. Future work is focused on elucidating the biologic underpinnings of disease to support an evolution in risk categorization, advancements in the multidimensional care required to treat these patients, and the discovery of novel therapies.

Congenital hepatoblastoma presenting with hepatic arteriovenous fistulas: a case report

Aim

Congenital hepatoblastoma, a rare malignant liver tumor in infancy, typically presents with abdominal distension or mass. Tumors detected antenatally or during the first three months of age are considered congenital hepatoblastoma. Hepatic arteriovenous fistulas (HAVF) are associated with high mortality in the neonatal period and can be caused by many secondary factors. This case report focuses on a patient with congenital hepatoblastoma accompanied by HAVF, highlighting the clinical and imaging characteristics and management strategies.

Case presentation

A term infant presented with sudden tachypnea and heart failure on his first day of life. A cystic-solid mixed lesion in the fetus's liver was detected by an antenatal ultrasound scan. Postnatal digital subtraction angiography confirmed the presence of arteriovenous fistulas, which were treated with trans-arterial embolization. However, despite the intervention, the patient's heart failure did not improve. The patient underwent a left hepatectomy, and hepatoblastoma was discovered by histology of the resected hepatic lobe. Unfortunately, metastases were later discovered in the intracranial and ocular regions. Ultimately, the family decided to discontinue further treatment.

Conclusion

Congenital hepatoblastoma presenting with hepatic arteriovenous fistulas has not been previously described. Hepatoblastoma should be considered when alpha-fetoprotein levels show a significant elevation in newborns. Prenatal diagnosis may improve pre- and postnatal management.

Consensus classification of pediatric hepatocellular tumors: A report from the Children's Hepatic tumors International Collaboration (CHIC)

BACKGROUND

Liver tumors are rare in children with histologic heterogeneity that makes diagnosis challenging. Systematic histopathological review, performed as part of collaborative therapeutic protocols, identified relevant histologic subtypes that are important to distinguish. The Children's Hepatic tumors International Collaboration (CHIC) was established to study pediatric liver tumors on a global scale and led to establishment of a provisional consensus classification for use in international clinical trials. The current study is the validation of this initial classification and first large-scale application by international expert reviewers.

PROCEDURE

The CHIC initiative includes data from 1605 children treated on eight multicenter hepatoblastoma (HB) trials. Review of 605 available tumors was performed by seven expert pathologists from three consortia (US, EU, Japan). Cases with discordant diagnoses were collectively reviewed to reach a final consensus diagnosis.

RESULTS

Of 599 cases with sufficient material for review, 570 (95.2%) were classified as HB by all consortia, and 29 (4.8%) as non-HB, which included "hepatocellular neoplasm, NOS" and malignant rhabdoid tumors. 453 of 570 HBs were classified as epithelial by final consensus. Some patterns (i.e., small cell undifferentiated, macrotrabecular, cholangioblastic) were selectively identified by reviewers from different consortia. All consortia identified a similar number of mixed epithelial-mesenchymal HB.

CONCLUSIONS

This study represents the first large-scale application and validation of the pediatric malignant hepatocellular tumors consensus classification. It is a valuable resource to train future generations of investigators on accurate diagnosis of these rare tumors and provides a framework for further international collaborative studies and refinement of the current classification of pediatric liver tumors.

SLC-0111, an inhibitor of carbonic anhydrase IX, attenuates hepatoblastoma cell viability and migration

Background

In response to hypoxia, tumor cells undergo transcriptional reprogramming including upregulation of carbonic anhydrase (CA) IX, a metalloenzyme that maintains acid-base balance. CAIX overexpression has been shown to correlate with poor prognosis in various cancers, but the role of this CA isoform in hepatoblastoma (HB) has not been examined.

Methods

We surveyed the expression of CAIX in HB specimens and assessed the impact of SLC-0111, a CAIX inhibitor, on cultured HB cells in normoxic and hypoxic conditions.

Results

CAIX immunoreactivity was detected in 15 out of 21 archival pathology HB specimens. The CAIX-positive cells clustered in the middle of viable tumor tissue or next to necrotic areas. Tissue expression of CAIX mRNA was associated with metastasis and poor clinical outcome of HB. Hypoxia induced a striking upregulation of CAIX mRNA and protein in three HB cell models: the immortalized human HB cell line HUH6 and patient xenograft-derived lines HB-295 and HB-303. Administration of SLC-0111 abrogated the hypoxia-induced upregulation of CAIX and decreased HB cell viability, both in monolayer and spheroid cultures. In addition, SLC-0111 reduced HB cell motility in a wound healing assay. Transcriptomic changes triggered by SLC-0111 administration differed under normoxic vs. hypoxic conditions, although SLC-0111 elicited upregulation of several tumor suppressor genes under both conditions.

Conclusion

Hypoxia induces CAIX expression in HB cells, and the CAIX inhibitor SLC-0111 has in vitro activity against these malignant cells.

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.

Incidence and 5-year survival of children and adolescents with hepatoblastoma in the United States

OBJECTIVE

Hepatoblastoma (HB) is the most common pediatric primary malignant liver tumor, its incidence has been increasing worldwide, but recent changes in incidence and outcomes with high population coverage are not well characterized.

METHODS

We defined the incidence of HB diagnosed during 2003-2017 from United States Cancer Statistics (USCS) database, and survival during 2001-2016 from the National Program of Cancer Registries (NPCR). Data were stratified by sex, race/ethnicity, age, tumor stage, county population, and diagnosis year. Incidence trends were assessed by calculating average annual percent change (AAPC) using Joinpoint regression. Differences in overall 5-year survival were estimated using Cox regression analysis.

RESULTS

2178 HB cases with an annual incidence rate of 1.76 per million persons were identified and incidence increased over time (AAPC = 2.2, 95% confidence interval [CI], 0.9-3.6). The 5-year relative survival was 76.9% (95% CI: 74.9-78.8) and the risk of death was lower for cases diagnosed after 2009 (hazard ratio [HR] = 0.77, 95% CI: 0.63-0.94), higher for ages 3-7 years and 8-19 years compared to 0-2 years (HR = 1.38, 95% CI: 1.10-1.76 and 1.83, 95% CI: 1.31-2.70, respectively), for distant compared to locoregional stage (HR = 2.77, 95% CI: 2.27-3.36), and for non-Hispanic Black compared to non-Hispanic White cases (HR = 1.39, 95% CI: 1.02-1.84).

CONCLUSIONS

HB incidence increased, and survival improved over the study period. Disparities in survival exist by age, race or ethnicity, and stage. Further studies could identify factors affecting increases in HB cases, inform future interventions, and address disparities in outcomes.

Hepatoblastomas with carcinoma features represent a biological spectrum of aggressive neoplasms in children and young adults

BACKGROUND & AIMS

Hepatoblastoma (HB) and hepatocellular carcinoma (HCC) are the predominant liver cancers in children, though their respective treatment options and associated outcomes differ dramatically. Risk stratification using a combination of clinical, histological, and molecular parameters can improve treatment selection, but it is particularly challenging for tumors with mixed histological features, including those in the recently created hepatocellular neoplasm not otherwise specified (HCN NOS) provisional category. We aimed to perform the first molecular characterization of clinically annotated cases of HCN NOS.

METHODS

We tested whether these histological features are associated with genetic alterations, cancer gene dysregulation, and outcomes. Namely, we compared the molecular features of HCN NOS, including copy number alterations, mutations, and gene expression profiles, with those in other pediatric hepatocellular neoplasms, including HBs and HCCs, as well as HBs demonstrating focal atypia or pleomorphism (HB FPAs), and HBs diagnosed in older children (>8).

RESULTS

Molecular profiles of HCN NOS and HB FPAs revealed common underlying biological features that were previously observed in HCCs. Consequently, we designated these tumor types collectively as HBs with HCC features (HBCs). These tumors were associated with high mutation rates (∼3 somatic mutations/Mb) and were enriched with mutations and alterations in key cancer genes and pathways. In addition, recurrent large-scale chromosomal gains, including gains of chromosomal arms 2q (80%), 6p (70%), and 20p (70%), were observed. Overall, HBCs were associated with poor clinical outcomes.

CONCLUSIONS

Our study indicates that histological features seen in HBCs are associated with combined molecular features of HB and HCC, that HBCs are associated with poor outcomes irrespective of patient age, and that transplanted patients are more likely to have good outcomes than those treated with chemotherapy and surgery alone. These findings highlight the importance of molecular testing and early therapeutic intervention for aggressive childhood hepatocellular neoplasms.

LAY SUMMARY

We molecularly characterized a class of histologically aggressive childhood liver cancers and showed that these tumors are clinically aggressive and that their observed histological features are associated with underlying recurrent molecular features. We proposed a diagnostic algorithm to identify these cancers using a combination of histological and molecular features, and our analysis suggested that these cancers may benefit from specialized treatment strategies that may differ from treatment guidelines for other childhood liver cancers.

Current Approaches in Hepatoblastoma-New Biological Insights to Inform Therapy

PURPOSE OF REVIEW

As the most common pediatric primary liver cancer with rising incidence, hepatoblastoma remains challenging to treat. Here, we review the current understanding of the biology of hepatoblastoma and discuss how recent advances may lead to new treatment modalities.

RECENT FINDINGS

Standard chemotherapy regimens including cisplatin, in addition to surgery, have led to high cure rates among patients with low stage hepatoblastoma; however, metastatic and relapsed disease continue to have poor outcomes. Recent genomics and functional studies in cell lines and mouse models have established a central role for the Wnt/β-catenin pathway in tumorigenesis. Targeted agents and immunotherapy approaches are emerging as potential treatment avenues. With recent gains in knowledge of the genomic and transcriptomic landscape of hepatoblastoma, new therapeutic mechanisms can now be explored to improve outcomes for metastatic and relapsed hepatoblastoma and to reduce the toxicity of current treatments.

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.

Feasibility of dose-dense cisplatin-based chemotherapy in Japanese children with high-risk hepatoblastoma: Analysis of the JPLT3-H pilot study

BACKGROUND

The SIOPEL-4 study has demonstrated that dose-dense cisplatin-based chemotherapy dramatically improves outcome in children with high-risk hepatoblastoma in western countries. However, the feasibility and safety of this regimen have not been clarified in Japanese patients.

METHODS

A pilot study, JPLT3-H, was designed to evaluate the safety profile of the SIOPEL-4 regimen in Japanese children with newly diagnosed hepatoblastoma with either metastatic disease or low alpha-fetoprotein.

RESULTS

A total of 15 patients (three female) were enrolled. Median age was 2 years (range, 0-14). Three patients were PRETEXT II (where PRETEXT is PRETreatment EXTent of disease), six PRETEXT III, and six PRETEXT IV. All patients had lung metastasis, none had low alpha-fetoprotein. Eight patients completed the prescribed treatment, and seven patients discontinued therapy prematurely, four due to progressive disease and three due to causes other than severe toxicity. Grade 4 neutropenia was documented in most patients in preoperative cycles A1-3 (11/15 in A1, 9/11 in A2, and 7/11 in A3) and in all considering all cycles. Grade 3-4 thrombocytopenia and grade 3 anemia were also frequently observed. Patients experienced several episodes of grade 3 febrile neutropenia, but none had grade 4 febrile neutropenia or severe infections. One patient had grade 3 heart failure only in the first cycle. Other grade 3 or 4 toxicities were hypomagnesemia, anorexia, nausea, mucositis, liver enzyme elevation, fever, infection, and fatigue. There were no unexpected severe toxicities.

CONCLUSION

The toxicity profile of JPLT3-H was comparable to that of SIOPEL-4. Dose-dense cisplatin-based chemotherapy may be feasible among Japanese patients with high-risk hepatoblastoma.

A Systematic Review and Meta-Analysis of Malignant Rhabdoid and Small Cell Undifferentiated Liver Tumors: A Rational for a Uniform Classification

Simple Summary

Malignant rhabdoid tumors of the liver are very rare pediatric liver tumors with a devastating prognosis. It is currently unclear which histological subtypes of pediatric liver tumors belong to this entity and how these tumors should be treated. In this systematic review with meta-analysis, we analyzed all reports on pediatric patients with malignant rhabdoid liver tumors, but also with so-called small cell undifferentiated liver tumors. This is another rare liver tumor subtype that has recently been regarded to belong to the entity of rhabdoid tumors by some authors. The main result of this study is that these two tumor subtypes show large overlap on several levels and even mixtures of both histological patterns have been documented. Our meta-analysis provides an evidence base for the recommendation to classify these two tumor subtypes as one entity. We showed that treatment of these tumors with hepatoblastoma directed chemotherapy is ineffective and that a therapy with chemotherapy regimens initially applied for soft tissue sarcoma is associated with a significantly better survival. This study represents the highest level of evidence available for these rare liver tumors.

Abstract

Background: Rhabdoid liver tumors in children are rare and have a devastating prognosis. Reliable diagnosis and targeted treatment approaches are urgently needed. Immunohistochemical and genetic studies suggest that tumors formerly classified as small cell undifferentiated hepatoblastoma (SCUD) belong to the entity of malignant rhabdoid tumors of the liver (MRTL), in contrast to hepatoblastomas with focal small cell histology (F-SCHB). This may have relevant implications on therapeutic approaches. However, studies with larger cohorts investigating the clinical relevance of the histological and genetic similarities for patients are lacking. Purpose: To analyze possible similarities and differences in patient characteristics, tumor biology, response to treatment, and clinical course of patients with MRTL, SCUD and F-SCHB. Applied therapeutic regimens and prognostic factors are investigated. Methods: A systematic literature search of MEDLINE, Web of Science, and CENTRAL was performed for this PRISMA-compliant systematic review. All studies of patients with MRTL, SCUD and F-SCHB that provided individual patient data were included. Demographic, histological, and clinical characteristics of the three subgroups were compared. Overall survival (OS) was estimated with the Kaplan–Meier method and prognostic factors investigated in a multivariable Cox regression model. Protocol registered: PROSPERO 2021 CRD42021258760. Results: Fifty-six studies with a total of 118 patients were included. The two subgroups MRTL and SCUD did not differ significantly in baseline patient characteristics. However, heterogenous diagnostic and therapeutic algorithms were applied. Large histological and clinical overlap between SCUD and MRTL could be shown. Two-year OS was 22% for MRTL and 13% for SCUD, while it was significantly better in F-SCHD (86%). Chemotherapeutic regimens for hepatoblastoma proved to be ineffective for both SCUD and MRTL, but successful in F-SCHB. Soft tissue sarcoma chemotherapy was associated with significantly better survival for MRTL and SCUD, but was rarely applied in SCUD. Patients who did not undergo surgical tumor resection had a significantly higher risk of death. Conclusions: While F-SCHB is a subtype of HB, SCUD should be classified and treated as a type of MRTL. Surgical tumor resection in combination with intensive, multi-agent chemotherapy is the only chance for cure of these tumors. Targeted therapies are highly needed to improve prognosis. Currently, aggressive regimens including soft tissue sarcoma chemotherapy, extensive resection, radiotherapy or even liver transplantation are the only option for affected children.

Factors influencing recurrence after complete remission in children with hepatoblastoma: A 14-year retrospective study in China

Objective

After a complete remission to treatment for hepatoblastoma, some children still have recurrence. We identified and explored the factors that influence recurrence after complete remission in a retrospective study.

Methods

Of 197 children with hepatoblastoma, 140 (71.1%) achieved initial complete remission and were enrolled in factor analysis. Variables consisted of age, sex, PRE-Treatment EXTent of tumor (PRETEXT) stage, pathologic type, metastatic disease, serum alpha-fetoprotein level, vascular involvement, and surgical margin status. We employed univariate and multivariate analyses to assess the relationship between each factor and tumor recurrence.

Results

Of 140 children who achieved initial complete remission, 42 (30%) had recurrent hepatoblastoma. The 5-year overall survival rates for the non-recurrence and recurrence group were 99.0% and 78.6%, respectively. The overall 1-year, 3-year, and 5-year recurrence-free survival (RFS) rates were 77.8%, 69.8%, and 69.8%, respectively. All recurrences occurred within 2 years from complete remission. The RFS rate was significantly higher in children younger than 3 years and in those with mixed pathological type, PRETEXT II and III, without metastatic disease, without vascular involvement, and microscopic negative margin than in that of children older than 3 years, with epithelial pathological type, PRETEXT IV, metastatic disease, vascular involvement, and macroscopic positive margin (P < 0.001, = 0.020, < 0.001, = 0.004, = 0.002, and < 0.001, respectively). The independent risk factors for recurrence after complete remission were age ≥3 years, PRETEXT IV, and metastatic disease (P < 0.05).

Conclusion

Age, PRETEXT stage, metastatic disease, vascular involvement, pathologic type, and surgical margin status might be associated with recurrent hepatoblastoma after complete remission; meanwhile, age ≥3 years, PRETEXT IV, and metastatic disease are independent risk factors of recurrence. Further research is needed on the causes of tumor recurrence, which may improve the long-term outcomes of children with hepatoblastoma.

Polymorphisms in METTL3 gene and hepatoblastoma risk in Chinese children: A seven-center case-control study

Hepatoblastoma is the most common malignant liver cancer in childhood, yet its etiology remains unclear. As an m⁶A methylation modifier, methyltransferase like 3 (METTL3) has an active methyltransferase domain that functionally participates in various tumor occurrence and development. However, little is known about how METTL3 polymorphisms affect the occurrence of hepatoblastoma. Here, we attempted to investigate the associations between METTL3 gene polymorphisms and hepatoblastoma risk in a seven-center case-control study. We genotyped four METTL3 polymorphisms (rs1061026 T > G, rs1061027 C > A, rs1139130 A > G, rs1263801 G > C) by TaqMan technique in 313 cases and 1446 controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to evaluate the contributions of these four single nucleotide polymorphisms (SNPs) to hepatoblastoma susceptibility. In single genotype analysis, we detected no significant correlation between these four polymorphisms in METTL3 and hepatoblastoma risk. However, in the combined analysis, the presence of 2-4 risk genotypes of METTL3 was associated with an increased risk of hepatoblastoma compared with that of 0-1 risk genotypes (adjusted OR = 1.48, 95% CI = 1.03-2.12, P = 0.035). The stratified analysis further revealed that carriers of 2-4 risk genotypes are more susceptible to hepatoblastoma in the subgroups of subjects aged under 17 months (adjusted OR = 1.88, 95% CI = 1.12-3.16, P = 0.016) and females (adjusted OR = 1.79, 95% CI = 1.06-3.05, P = 0.031). Overall, our results revealed that none of these four SNPs could increase susceptibility to hepatoblastoma individually. Carriers with 2-4 risk genotypes in the combined analysis tend to increase the risk of hepatoblastoma.

Genetic and epigenetic basis of hepatoblastoma diversity

Hepatoblastoma (HB) is the most common pediatric liver malignancy; however, hereditary predisposition and acquired molecular aberrations related to HB clinicopathological diversity are not well understood. Here, we perform an integrative genomic profiling of 163 pediatric liver tumors (154 HBs and nine hepatocellular carcinomas) based on the data acquired from a cohort study (JPLT-2). The total number of somatic mutations is precious low (0.52/Mb on exonic regions) but correlated with age at diagnosis. Telomerase reverse transcriptase (TERT) promoter mutations are prevalent in the tween HBs, selective in the transitional liver cell tumor (TLCT, > 8 years old). DNA methylation profiling reveals that classical HBs are characterized by the specific hypomethylated enhancers, which are enriched with binding sites for ASCL2, a regulatory transcription factor for definitive endoderm in Wnt-pathway. Prolonged upregulation of ASCL2, as well as fetal-liver-like methylation patterns of IGF2 promoters, suggests their "cell of origin" derived from the premature hepatoblast, similar to intestinal epithelial cells, which are highly proliferative. Systematic molecular profiling of HB is a promising approach for understanding the epigenetic drivers of hepatoblast carcinogenesis and deriving clues for risk stratification.

High Expression of ROMO1 Aggravates the Malignancy of Hepatoblastoma

Hepatoblastoma (HB) is a kind of tumor that occurs frequently in children and is highly malignant. Here, the function of ROS modulator 1 (ROMO1) was identified in the development of HB. In this study, the mRNA expression of ROMO1 was measured by RT-qPCR. Colony formation assay, MTT assay, and flow cytometric analysis were applied to detect cell viability. The cell migrative and invasive ability was measured by wound healing and transwell assays. Tumor xenografts were performed to examine tumor growth. The results showed that upregulation of ROMO1 was identified in liver hepatocellular carcinoma (LIHC) tissues and predicted poor prognosis in LIHC patients. And ROMO1 expression was also increased in HB tissues and cells. Functionally, ROMO1 knockdown restrained cell viability, migration, and invasion in HB. In addition, knockdown of ROMO1 was found to suppress tumor formation in vivo. In conclusion, upregulation of ROMO1 promotes tumor growth and cell aggressiveness in HB.

Trans-Ancestry Mutation Landscape of Hepatoblastoma Genomes in Children

Hepatoblastoma (HB) is the most common malignant tumor in the liver of infants and young children. The incidence rate varies among different populations. However, genetic differences in HB patients with different epidemiological and ancestral backgrounds have not been found. In this study, we aim to analyze data from 16 patients treated at our center and collected published data from whole-exome sequencing studies on HB, and to explore the genetic differences between races. Data from a total of 75 HB patients of three races (24 Asian, 37 Caucasian and 14 Hispanic) were analyzed. We identified 16 genes with recurrent somatic mutations and 7 core pathway modules. Among them, the Wnt/β-catenin pathway had the highest mutation rate, and the mutation frequency in Caucasians and Hispanics was approximately twice as high as that in Asians. In addition, this study compared the characteristics of gene mutations between patients who underwent preoperative chemotherapy and those who did not and found that there was no significant difference in gene mutations between the two groups. We also preliminarily verified the function of cancer-associated candidate genes (CTNNB1 and KMT2D). In conclusion, we found ethnic differences in HB biology at the genomic level, which expands our understanding of the genetics of HB in children.

Preoperative Assessment for Event-Free Survival With Hepatoblastoma in Pediatric Patients by Developing a CT-Based Radiomics Model

Objective: To explore a CT-based radiomics model for preoperative prediction of event-free survival (EFS) in patients with hepatoblastoma and to compare its performance with that of a clinicopathologic model.

Patients and Methods: Eighty-eight patients with histologically confirmed hepatoblastoma (mean age: 2.28 ± 2.72 years) were recruited from two institutions between 2002 and 2019 for this retrospective study. They were divided into a training cohort (65 patients from institution A) and a validation cohort (23 patients from institution B). Radiomics features were extracted manually from pretreatment CT images in the portal venous (PV) phase. The least absolute shrinkage and selection operator (LASSO) Cox regression model was applied to construct a “radiomics signature” and radiomics score (Rad-score) for EFS prediction. Then, a nomogram incorporating the Rad-score, updated staging system, and significant variables of clinicopathologic risk (age, alpha-fetoprotein (AFP) level, histology subtype, tumor diameter) as the radiomic model, clinicopathologic model, and combined clinicopathologic-radiomic model were built for EFS estimation in the training cohort, the performance of which was assessed in an external-validation cohort with respect to clinical usefulness, discrimination, and calibration.

Results: Nine survival-relevant features were selected for a radiomics signature and Rad-score building. Multivariable analysis revealed that histology subtype (P = 0.01), PV (P = 0.001) invasion, and metastasis (P = 0.047) were independent risk factors of EFS. Patients were divided into low- and high-risk groups based on the Rad-score with a cutoff of 0.08 according to survival outcome. The radiomics signature-incorporated nomogram showed good performance (P < 0.001) for EFS estimation (C-Index: 0.810; 95% CI: 0.738–0.882), which was comparable with that of the clinicopathological model for EFS estimation (C-Index: 0.81 vs. 0.85). The radiomics-based nomogram failed to show incremental prognostic value compared with that using the clinicopathologic model. The combined model (radiomics signature plus clinicopathologic parameters) showed significant improvement in the discriminatory accuracy, along with good calibration and greater net clinical benefit, of EFS (C-Index: 0.88; 95% CI: 0.829–0.933).

Conclusion: The radiomics signature can be used as a prognostic indicator for EFS in patients with hepatoblastoma. A combination of the radiomics signature and clinicopathologic risk factors showed better performance in terms of EFS prediction in patients with hepatoblastoma, which enabled precise clinical decision-making.

A new risk-stratification system for hepatoblastoma in children under six years old and the significance for prognosis evaluation-a 14-year retrospective study from a single center

BACKGROUND

This study explores and analyzes the clinical characteristics and prognostic factors of hepatoblastoma (HB) in children under 6 years old and establishes a new risk-stratification system for individualized therapy.

METHODS

The clinical data of 382 pediatric patients under 6 years old (231 males and 151 females) who had been diagnosed with HB by pathology between May 2005 and May 2019 were collected. By analyzing the risk factors influencing the survival rate of patients with HB, a new risk-stratification system was established, and it was compared with previous risk-stratification systems by a receiver operating characteristic (ROC) curve.

RESULTS

(1) According to a Kaplan-Meier survival analysis, the one-year, three-year, and five-year overall survival (OS) was 93.7, 84.0, and 73.9%, respectively, and the event-free survival (EFS) was 90.5, 79.2, and 67.5%, respectively. (2) The independent risk factors influencing prognosis in pediatric patients with HB were alpha-fetoprotein (AFP) < 100 ng/ml or > 1000 ng/ml (HR = 3.341, P = 0.005); platelet count > 400 × 10⁹/L (pooled hazard ratio [HR] = 2.123, P = 0.026); PRETEXT stage IV (HR = 4.026, P = 0.001); vascular involvement (HR = 2.178, P = 0.019); distant metastasis (HR = 2.634, P = 0.010);and multifocality (HR = 2.215, P = 0.012). (3) A new risk-stratification system was established and divided into three groups: low risk, moderate risk, and high risk. There were statistical differences among the three groups (P = 0.002). Compared with the previous risk-staging systems, there was no significant difference in the survival rate. Although the effect in the guiding therapy was the same, the area under the curve for the ROC curve was 0.835 (95% CI: 0.784-0.885) for the new stratification system.

CONCLUSION

This new risk-stratification system had a better predictive value for the prognosis of pediatric patients with HB than other stratification systems.

Clinical Characteristics and Prognosis Analysis of Infantile Hepatoblastoma-A 15-Year Retrospective Single-Center Study

Objective

The present study aimed to summarize the clinical data of hepatoblastoma (HB) in infants under one year of age and to analyze the factors that affected the prognoses.

Methods

The clinical data of 132 pediatric patients with a pathologically confirmed HB, aged less than one year and who had visited the Pediatric Single Center of Beijing Tongren Hospital from May 2005 to May 2019, were retrospectively analyzed to summarize the clinical outcomes and prognoses.

Results

The male/female ratio was 1.27 and the median age was 8.40 months. The onset of HB was usually characterized by abdominal bulging (75.0%). The median level of AFP at the first visit was 154.7µg/mL, and the average platelet count was (405±166)×10⁹/L. The epithelial type (57.6%) was the predominant pathological type, and stage III (54.5%) was the main PRETEXT staging. Distant metastases occurred in 45 cases, with pulmonary metastases (86.7%) being the most common site. At the time of visit, 24 cases (18.2%) had either portal vein, hepatic vein, or vena cava infiltration. Five cases (3.8%) had a hemorrhage of the ruptured tumor, and 26 cases (19.7%) had multiple intrahepatic foci. At the follow-up in May 2020, the overall survival (OS) rate at one, three, and five years of age was 94.3%, 88.8%, and 80.1%, respectively, and the event-free survival rate was 91.8%, 86.9%, and 77.5%, respectively, by the Kaplan–Meier survival analysis. According to the Log rank test, pediatric patients with an AFP <100ng/mL, a PRETEXT stage IV, presence of distant metastases and multiple foci of the primary tumor at the initial diagnosis had poorer prognoses (P<0.05).

Conclusion

The prognosis of HB in infancy is relatively good, but is still vulnerable to multiple factors, such as tumor features leading to different AFP levels, PRETEXT stage, presence of distant metastases, and multiple intrahepatic foci.

Survival and prognostic factors for childhood malignant liver tumors: analysis of harmonized clinical data

BACKGROUND

Despite overall striking advances in survival of childhood liver tumors, outcomes remain poor for specific patient segments. We aimed to assess overall survival (OS) of this rare disease and evaluate the generalizability of prognostic variables included in international collaborative systems using, for the first time, harmonized clinical data from two geographically different cohorts (Greece and Moscow).

METHODS

Data for children (0-14 years) with liver tumors were retrieved from two Southern-Eastern European areas (Greece; 2001-2019 and Moscow; 2012-2019). Kaplan-Meier curves were constructed, and OS values were derived from Cox proportional models controlling for study variables.

RESULTS

A total of 171 newly diagnosed cases (54.4% males) were included. The OS_5-year exceeded 80% in patients <5 years, reaching 85% among 133 patients with hepatoblastoma (HBL). By contrast, children with other than HBL histology, especially hepatocellular carcinoma (HCC) had significantly worse prognosis (hazard ratio [HR] _HCC: 7.09, 95% confidence intervals [CI]: 2.56-19.65; HR _{other liver tumors}: 5.18; 95%CI: 2.15-12.49). The OS_5-year was poorer (40%-60%) in patients with extensive local, metastatic or relapsed disease. By contrast, a significantly lower risk of death was shown in case of microscopically margin-negative resection (HR: 0.06, 95%CI: 0.02-0.17) and liver transplantation (HR: 0.12, 95% CI: 0.02-0.63) compared to the non- operated group.

CONCLUSIONS

Outcomes of patients with liver tumors registered in two SEE areas were comparable to those reported by major collaborative trials. Ongoing clinical cancer registration could facilitate comparison of outcomes between different study groups in order to shape state of the art of treatment.

CHIC Risk Stratification System for Predicting the Survival of Children With Hepatoblastoma: Data From Children With Hepatoblastoma in China

Objective

The aim of this study was to compare the accuracy of the Children’s Oncology Group (COG) risk stratification system to the Children’s Hepatic tumor International Collaboration (CHIC) risk stratification system for predicting the prognosis of Chinese children with hepatoblastoma (HB).

Methods

Clinicopathological data of 86 patients diagnosed with HB between January 2014 and December 2017 were retrieved. The study endpoints were the 1- and 3-year overall survival (OS) and disease-free survival (DFS) were analyzed to evaluate the predictive value.

Results

The 1-, 3-year OS and DFS of the 86 patients were 86.0%, 76.3%, and 74.4%, 54.0%, respectively. Univariate analyses revealed that age at diagnosis had a significant role in prognosis for both OS and DFS, along with PRETEXT staging and metastasis at diagnosis. Multivariate analysis showed that metastasis at diagnosis (HR 3.628, 95% CI 1.404-9.378, P=0.008), PRETEXT staging system (HR 2.176, 95% CI 1.230-3.849, P=0.008) and age at diagnosis (HR 2.268, 95% CI 1.033-4.982, P=0.041) were independent factors for OS. For DFS, the independent factors were the PRETEXT staging system (HR 2.241, 95% CI 1.533-3.277, P<0.001) and age at diagnosis (HR 1.792, 95% CI 1.018-3.154, P=0.043). Both COG and CHIC risk stratification systems could effectively predict the prognosis of children with HB for OS. For DFS, the CHIC risk stratification system was more effective. In addition, the CHIC risk stratification system had a higher c-index (OS 0.743, DFS 0.730), compared to the COG risk stratification system (OS 0.726, DFS 0.594).

Conclusion

Age at diagnosis played a significant role in prognosis. Compared to the COG risk stratification system, the CHIC risk stratification system was superior in predicting the survival of Chinese children with HB.