Risk-stratified staging in paediatric hepatoblastoma: a unified analysis from the Children's Hepatic tumors International Collaboration

FOXM1 and CHD4 expression is associated with chemoresistance in hepatoblastoma

Hepatoblastoma (HB) is the most common malignant liver tumor in childhood. Although pre-operative cisplatin (CDDP)-based chemotherapy is often used in cases of HB, about 20％ of HB patients exhibit resistance to CDDP. Forkhead box protein M1 (FOXM1) and chromo-domain-helicase-DNA-binding protein 4 (CHD4) have been associated with CDDP resistance in various tumors. We here analyzed the immunohistochemical expression of FOXM1 and CHD4 in HB specimens of 33 patients (mean age: 20 months) post-chemotherapy. The differentiation of specimens was assessed using the digital pathology software QuPath®, and then the relation between the FOXM1 or CHD4 expression and the differentiation and various other clinicopathological parameters was investigated. The histological type was epithelial in 19 cases (57.6%) and mixed epithelial and mesenchymal in 14 cases (42.4%). Nine cases had only a fetal component, 1 case had only an embryonal component, 22 cases had both fetal and embryonal components, and 1 case had no viable tumor. Both the FOXM1 and CHD4 immunoexpressions were found significantly more frequently in the embryonal than fetal components (p<0.0001 and p<0.0001, respectively). Regarding chemotherapy efficacy, the alpha-fetoprotein (AFP) level after chemotherapy was correlated with both the imaging shrinkage rate (R=-0.52) and histological residual rate (the percentage of the viable tumors of HB after chemotherapy)(R=0.62). High FOXM1 score was correlated with a high-postoperative AFP value (p<0.01) and a low AFP attenuation rate (p<0.05), but the FOXM1 score was not correlated with the imaging shrinkage rate (p=0.4418) or histological residual rate (p=0.4418). High CHD4 score showed a nonsignificant trend toward correlation with high postoperative AFP value (p=0.0849) and was not significantly correlated with the other parameters. Collectively, our results showed that FOXM1 expression may be useful in evaluating the response to CDDP-based chemotherapeutic regimens. Accurate measurement of FOXM1 expression by our scoring system using QuPath® is important in cases with mixed HB components of various differentiation levels.

An indocyanine green-based liquid biopsy test for circulating tumor cells for pediatric liver cancer

BACKGROUND

Hepatoblastoma and HCC are the most common malignant hepatocellular tumors seen in children. The aim of this study was to develop a liquid biopsy test for circulating tumor cells (CTCs) for these tumors that would be less invasive and provide real-time information about tumor response to therapy.

METHODS

For this test, we utilized indocyanine green (ICG), a far-red fluorescent dye used clinically to identify malignant liver cells during surgery. We assessed ICG accumulation in cell lines using fluorescence microscopy and flow cytometry. For our CTC test, we developed a panel of liver tumor-specific markers, including ICG, Glypican-3, and DAPI, and tested it with cell lines and noncancer control blood samples. We then used this panel to analyze whole-blood samples for CTC burden with a cohort of 15 patients with hepatoblastoma and HCC and correlated with patient characteristics and outcomes.

RESULTS

We showed that ICG accumulation is specific to liver cancer cells, compared to nonmalignant liver cells, non-liver solid tumor cells, and other nonmalignant cells, and can be used to identify liver tumor cells in a mixed population of cells. Experiments with the ICG/Glypican-3/DAPI panel showed that it specifically tagged malignant liver cells. Using patient samples, we found that CTC burden from sequential blood samples from the same patients mirrored the patients' responses to therapy.

CONCLUSIONS

Our novel ICG-based liquid biopsy test for CTCs can be used to specifically detect and quantify CTCs in the blood of pediatric patients with liver cancer.

Immunosuppression in liver transplant oncology: position paper of the Italian Board of Experts in Liver Transplantation (I-BELT)

Liver transplant oncology (TO) represents an area of increasing clinical and scientific interest including a heterogeneous group of clinical-pathological settings. Immunosuppressive management after LT is a key factor relevantly impacting result. However, disease-related guidance is still lacking, and many open questions remain in the field. Based on such a substantial lack of solid evidences, the Italian Board of Experts in Liver Transplantation (I-BELT) (a working group including representatives of all national transplant centers), unprecedently promoted a methodologically sound consensus conference on the topic, based on the GRADE approach. The group final recommendations are herein presented and commented. The 18 PICOs and Statements and their levels of evidence and grades of recommendation are reported and grouped into seven areas: (1) risk stratification by histopathological and bio-molecular parameters and role of mTORi post-LT; (2) steroids and HCC recurrence; (3) management of immunosuppression when HCC recurs after LT; (4) mTORi monotherapy; (5) machine perfusion and HCC recurrence after LT; (6) physiopathology of tumor-infiltrating lymphocytes and immunosuppression, the role of inflammation; (7) immunotherapy in liver transplanted patients. The interest in mammalian targets of rapamycin inhibitors (mTORi), for steroid avoidance and the need for a reduction to CNI exposure emerged from the consensus process. A selected list of unmet needs prompting further investigations have also been developed. The so far heterogeneous and granular approach to immunosuppression in oncologic patients deserves greater efforts for a more standardized therapeutic response to the different clinical scenarios. This consensus process makes a first unprecedented step in this direction, to be developed on a larger scale.

Nur77 inhibition of β-catenin expression mediates Hepatoblastoma progression and enhances cisplatin's therapeutic effect

Hepatoblastoma (HB) is the most common malignant tumor in children under 5 years old, but its pathogenesis remains unclear. Nur77 has been reported to be an important regulator for cancer progression in various cancer types. This study found that Nur77 was downregulated in HB tumors, compared with paracancer tissue. Knockout or overexpression of Nur77 in HB tumor cell line HepG2 and HuH6 could significantly enhance or inhibit the proliferation, migration and invasion of tumor cells both in vitro and in vivo. Further studies illustrated that Nur77 regulated the proliferation of tumor cells by affecting the expression of β-catenin. Nur77 agonist Csn-B effectively enhanced the therapeutic effect of cisplatin on HB tumors both in vitro and in vivo. This study confirms that Nur77 may act as an oncogene in HB tumors and mediate the progression of HB by inhibiting the expression of β-catenin, which provides a new targeted therapy for the clinical treatment of HB patients; meanwhile, the combination of Nur77 agonist and cisplatin treatment may improve the chemotherapeutic efficacy of HB patients, which provides a new idea for the improvement of the clinical prognosis of HB patients.

Construction and validation of nomogram prognostic model for predicting survival in hepatoblastoma patients: a population-based study

For patients with hepatoblastoma (HB), current staging system is not accurate in predicting survival outcomes. The aim of this study was to develop two accurate survival prediction models to guide clinical decision making. A retrospective analysis of 424 HB patients was performed from 2004 to 2015 using the Surveillance, Epidemiology and End Results (SEER) database. Univariate and multivariate Cox regression analysis was used to screen for variables. The identified variables were used to build survival prediction model. The performance of the nomogram models was assessed based on the concordance index (C-index), calibration plot, and receiver operating characteristic (ROC) curve. The Cox regression analysis identified six variables affecting overall survival (OS) in HB patients, including race, tumor size, lymph node involvement, distant metastases, surgery and chemotherapy. And the Cox regression analysis identified five variables including race, lymph node involvement, distant metastases, surgery, and chemotherapy that affect cancer-specific survival (CCS) in HB patients. In the training cohort, the C-index of the nomogram in predicting the OS was 0.791 [95% confidence intervals (95% CI) 0.717-0.865], CSS was 0.805(95% CI 0.728-0.882). In the validation cohort, the C-index of the nomogram in predicting the OS was 0.712 (95% CI 0.511-0.913), the CSS was 0.751 (95% CI 0.566-0.936). In the training cohort, the area under the receiver operator characteristics curve (AUC) values of the nomogram in prediction of the 1-, 3-, and 5-year OS were 0.842 (95% CI 0.739-0.944), 0.759 (95% CI 0.670-0.849), and 0.770 (95% CI 0.686-0.852), respectively. In the validation cohort, the AUC values for prediction of the 1-, 3-, and 5-year OS were 0.920 (95% CI 0.806-1.034), 0.863 (95% CI 0.750-0.976), and 0.844 (95% CI 0.721-0.967), respectively. Two nomogram models were developed and validated in this study which provided accurate prediction of the OS and CSS in HB patients. The constructed models can be used for predicting survival outcomes and guide treatment for HB patients.

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.

Computer-assisted three-dimensional individualized extreme liver resection for hepatoblastoma in proximity to the major liver vasculature

BACKGROUND

The management of hepatoblastoma (HB) becomes challenging when the tumor remains in close proximity to the major liver vasculature (PMV) even after a full course of neoadjuvant chemotherapy (NAC). In such cases, extreme liver resection can be considered a potential option.

AIM

To explore whether computer-assisted three-dimensional individualized extreme liver resection is safe and feasible for children with HB who still have PMV after a full course of NAC.

METHODS

We retrospectively collected data from children with HB who underwent surgical resection at our center from June 2013 to June 2023. We then analyzed the detailed clinical and three-dimensional characteristics of children with HB who still had PMV after a full course of NAC.

RESULTS

Sixty-seven children diagnosed with HB underwent surgical resection. The age at diagnosis was 21.4 ± 18.8 months, and 40 boys and 27 girls were included. Fifty-nine (88.1%) patients had a single tumor, 39 (58.2%) of which was located in the right lobe of the liver. A total of 47 patients (70.1%) had PRE-TEXT III or IV. Thirty-nine patients (58.2%) underwent delayed resection. After a full course of NAC, 16 patients still had close PMV (within 1 cm in two patients, touching in 11 patients, compressing in four patients, and showing tumor thrombus in three patients). There were 6 patients of tumors in the middle lobe of the liver, and four of those patients exhibited liver anatomy variations. These 16 children underwent extreme liver resection after comprehensive preoperative evaluation. Intraoperative procedures were performed according to the preoperative plan, and the operations were successfully performed. Currently, the 3-year event-free survival of 67 children with HB is 88%. Among the 16 children who underwent extreme liver resection, three experienced recurrence, and one died due to multiple metastases.

CONCLUSION

Extreme liver resection for HB that is still in close PMV after a full course of NAC is both safe and feasible. This approach not only reduces the necessity for liver transplantation but also results in a favorable prognosis. Individualized three-dimensional surgical planning is beneficial for accurate and complete resection of HB, particularly for assessing vascular involvement, remnant liver volume and anatomical variations.

First Transcriptome Analysis of Hepatoblastoma in Brazil: Unraveling the Pivotal Role of Noncoding RNAs and Metabolic Pathways

Hepatoblastoma stands as the most prevalent liver cancer in the pediatric population. Characterized by a low mutational burden, chromosomal and epigenetic alterations are key drivers of its tumorigenesis. Transcriptome analysis is a powerful tool for unraveling the molecular intricacies of hepatoblastoma, shedding light on the effects of genetic and epigenetic changes on gene expression. In this study conducted in Brazilian patients, an in-depth whole transcriptome analysis was performed on 14 primary hepatoblastomas, compared to control liver tissues. The analysis unveiled 1,492 differentially expressed genes (1,031 upregulated and 461 downregulated), including 920 protein-coding genes (62%). Upregulated biological processes were linked to cell differentiation, signaling, morphogenesis, and development, involving known hepatoblastoma-associated genes (DLK1, MEG3, HDAC2, TET1, HMGA2, DKK1, DKK4), alongside with novel findings (GYNG4, CDH3, and TNFRSF19). Downregulated processes predominantly centered around oxidation and metabolism, affecting amines, nicotinamides, and lipids, featuring novel discoveries like the repression of SYT7, TTC36, THRSP, CCND1, GCK and CAMK2B. Two genes, which displayed a concordant pattern of DNA methylation alteration in their promoter regions and dysregulation in the transcriptome, were further validated by RT-qPCR: the upregulated TNFRSF19, a key gene in the embryonic development, and the repressed THRSP, connected to lipid metabolism. Furthermore, based on protein-protein interaction analysis, we identified genes holding central positions in the network, such as HDAC2, CCND1, GCK, and CAMK2B, among others, that emerged as prime candidates warranting functional validation in future studies. Notably, a significant dysregulation of non-coding RNAs (ncRNAs), predominantly upregulated transcripts, was observed, with 42% of the top 50 highly expressed genes being ncRNAs. An integrative miRNA-mRNA analysis revealed crucial biological processes associated with metabolism, oxidation reactions of lipids and carbohydrates, and methylation-dependent chromatin silencing. In particular, four upregulated miRNAs (miR-186, miR-214, miR-377, and miR-494) played a pivotal role in the network, potentially targeting multiple protein-coding transcripts, including CCND1 and CAMK2B. In summary, our transcriptome analysis highlighted disrupted embryonic development as well as metabolic pathways, particularly those involving lipids, emphasizing the emerging role of ncRNAs as epigenetic regulators in hepatoblastomas. These findings provide insights into the complexity of the hepatoblastoma transcriptome and identify potential targets for future therapeutic interventions.

Histopathologic and immunophenotypic characterization of patient-derived pediatric malignant hepatocellular tumor xenografts (PDXs)

Advances in targeted therapies for pediatric hepatocellular tumors have been limited due to a paucity of clinically relevant models. Establishment and validation of intrahepatic patient-derived xenograft (PDX) models would help bridging this gap. The aim of this study is to compare the histomorphologic and immunophenotypic fidelity of patient tumors and their corresponding intrahepatic PDX models. Murine PDX models were established by intrahepatic implantation of patient tumors. Pathology slides from both patients and their corresponding PDX models were reviewed and quantitatively assessed for various histologic components and immunophenotypic markers. Ten PDX models were successfully established from nine patients with pre- (n=3) and post- (n=6) chemotherapy samples; diagnosed of hepatoblastoma (n=8) and hepatocellular neoplasm, not otherwise specified (n=1). Two of nine (22.2%) patients showed ≥75% fetal component; however, the corresponding PDX models did not maintain this fetal differentiation. High grade histology was seen in three patients (33.3%) and overrepresented in six PDX models (60%). Within the subset of three PDXs that were further characterized, significant IHC concordance was seen in all 3 models for CK7, CK19, Ki-67, and p53; and 2 of 3 models for Sox9 and Beta-catenin. GPC-3 and GS showed variable to moderate concordance, while Hepar was the least concordant. Our study shows that in general, the PDX models appear to represent the higher-grade component of the original tumor and show significant concordance for Ki-67, making them appropriate tools for testing new therapies for the most aggressive, therapy-resistant tumors.

Prognostic and predictive biomarkers in paediatric solid tumours

Characterisation of histological, immunohistochemical and molecular prognostic and predictive biomarkers has contributed significantly to precision medicine and better outcomes in the management of paediatric solid tumours. Prognostic biomarkers allow predictions to be made regarding a tumour's aggressiveness and clinical course, whereas predictive biomarkers help determine responses to a specific treatment. This review summarises prognostic biomarkers currently used in the more common paediatric solid tumours, with a brief commentary on the most relevant less common predictive biomarkers. MYCN amplification is the most important genetic alteration in neuroblastoma prognosis, and the histological classification devised by Shimada in 1999 is still used in routine diagnosis. Moreover, a new subgrouping of unfavourable histology neuroblastoma enables immunohistochemical characterisation of tumours with markedly different genetic features and prognosis. The predominant histology and commonly observed cytogenetic abnormalities are recognised outcome predictors in Wilms tumour. Evaluation for anaplasia, which is tightly associated with TP53 gene mutations and poor outcomes, is central in both the International Society of Paediatric Oncology and the Children's Oncology Group approaches to disease classification. Characterisation of distinct genotype-phenotype subclasses and critical mutations has expanded overall understanding of hepatoblastoma outcomes. The C1 subclass hepatoblastoma and CTNNB1 mutations are associated with good prognosis. In contrast, the C2 subclass, NFE2L2 mutations, TERT promoter mutations and high expression of oncofetal proteins and stem cell markers are associated with poor outcomes. Risk stratification in sarcomas is highly variable depending on the entity. The prognosis of rhabdomyosarcoma, for example, primarily depends on histological and molecular characteristics. Advances in our understanding of clinically significant biomarkers will translate into more precise diagnoses, improved risk stratification and more effective and less toxic treatment in this challenging group of patients.

Pediatric Hepatoblastoma After Neoadjuvant Chemotherapy: Diagnostic Performance of MR in Staging POSTTEXT and Vascular Involvement

BACKGROUND

The assessment of resectability after neoadjuvant chemotherapy of hepatoblastoma is dependent on Post-Treatment EXTENT of Disease (POSTTEXT) staging and its annotation factors P (portal venous involvement) and V (hepatic venous/inferior vena cava [IVC] involvement), but MR performance in assessing them remains unclear.

PURPOSE

To assess the diagnostic performance of contrast-enhanced MR imaging for preoperative POSTTEXT staging and diagnosing vascular involvement in terms of annotation factors P and V in pediatric hepatoblastoma following neoadjuvant chemotherapy.

STUDY TYPE

Retrospective.

SUBJECTS

Thirty-five consecutive patients (17 males, median age, 24 months; age range, 6-98 months) with proven hepatoblastoma underwent preoperative MR imaging following neoadjuvant chemotherapy.

FIELD STRENGTH/SEQUENCE

3.0 T; T2-weighted imaging (T2WI), T2WI with fat suppression, diffusion weighted imaging, radial stack-of-the-star/Cartesian 3D Dixon T1-weighted gradient echo imaging.

ASSESSMENT

Three radiologists independently assessed the POSTTEXT stages and annotation factors P and V based on the 2017 PRE/POSTTEXT system. The sensitivities and specificities were calculated for 1) diagnosing each POSTTEXT stage; 2) discrimination of stages III and IV (advanced) from those stages I and II (non-advanced) hepatoblastomas; and 3) annotation factors P and V. The combination of pathologic findings and surgical records served as the reference standard.

STATISTICAL TESTS

Sensitivity, specificity, Fleiss kappa test.

RESULTS

The sensitivity and specificity ranges for discriminating advanced from non-advanced hepatoblastomas were 73.3%-80.0% and 80.0%-90.0%, respectively. For annotation factor P, they were 66.7%-100.0% and 90.6%, respectively. For factor V, they were 75.0% and 67.7%-83.9%, respectively. There was excellent, substantial, and moderate agreement on POSTTEXT staging (Fleiss kappa = 0.82), factors P (Fleiss kappa = 0.64), and factors V (Fleiss kappa = 0.60), respectively.

DATA CONCLUSION

MR POSTTEXT provides reliable discrimination between advanced and non-advanced tumors, and MR has moderate to excellent specificity at identifying portal venous and hepatic venous/IVC involvement.

EVIDENCE LEVEL

3 TECHNICAL EFFICACY: Stage 3.

Mutational signature, cancer driver genes mutations and transcriptomic subgroups predict hepatoblastoma survival

BACKGROUND

Hepatoblastoma is the most frequent pediatric liver cancer. The current treatments lead to 80% of survival rate at 5 years. In this study, we evaluated the clinical relevance of molecular features to identify patients at risk of chemoresistance, relapse and death of disease.

METHODS

All the clinical data of 86 children with hepatoblastoma were retrospectively collected. Pathological slides were reviewed, tumor DNA sequencing (by whole exome, whole genome or target) and transcriptomic profiling with RNAseq or 300-genes panel were performed. Associations between the clinical, pathological, mutational and transcriptomic data were investigated.

RESULTS

High-risk patients represented 44% of our series and the median age at diagnosis was 21.9 months (range: 0-208). Alterations of the WNT/ß-catenin pathway and of the 11p15.5 imprinted locus were identified in 98% and 74% of the tumors, respectively. Other cancer driver genes mutations were only found in less than 11% of tumors. After neoadjuvant chemotherapy, disease-specific survival and poor response to neoadjuvant chemotherapy were associated with 'Liver Progenitor' (p = 0.00049, p < 0.0001) and 'Immune Cold' (p = 0.0011, p < 0.0001) transcriptomic tumor subtypes, SBS35 cisplatin mutational signature (p = 0.018, p = 0.001), mutations in rare cancer driver genes (p = 0.0039, p = 0.0017) and embryonal predominant histological type (p = 0.0013, p = 0.0077), respectively. Integration of the clinical and molecular features revealed a cluster of molecular markers associated with resistance to chemotherapy and survival, enlightening transcriptomic 'Immune Cold' and Liver Progenitor' as a predictor of survival independent of the clinical features.

CONCLUSIONS

Response to neoadjuvant chemotherapy and survival in children treated for hepatoblastoma are associated with genomic and pathological features independently of the clinical features.

Children's Oncology Group's 2023 blueprint for research: Surgery

Surgery plays a crucial role in the treatment of children with solid malignancies. A well-conducted operation is often essential for cure. Collaboration with the primary care team is important for determining if and when surgery should be performed, and if performed, an operation must be done in accordance with well-established standards. The long-term consequences of surgery also need to be considered. Indications and objectives for a procedure vary. Providing education and developing and analyzing new research protocols that include aims relevant to surgery are key objectives of the Surgery Discipline of the Children's Oncology Group. The critical evaluation of emerging technologies to ensure safe, effective procedures is another key objective. Through research, education, and advancing technologies, the role of the pediatric surgeon in the multidisciplinary care of children with solid malignancies will continue to evolve.

Summary of biological research on hepatoblastoma: a scoping review

Background

Hepatoblastoma is the most prevalent primary hepatic malignancy in children, comprising 80% of pediatric hepatic malignancies and 1% of all pediatric malignancies. However, traditional treatments have proven inadequate in effectively curing hepatoblastoma, leading to a poor prognosis.

Methods

A literature search was conducted on multiple electronic databases (PubMed and Google Scholar). A total of 86 articles were eligible for inclusion in this review.

Result

This review aims to consolidate recent developments in hepatoblastoma research, focusing on the latest advances in cancer-associated genomics, epigenetic studies, transcriptional programs and molecular subtypes. We also discuss the current treatment approaches and forthcoming strategies to address cancer-associated biological challenges.

Conclusion

To provide a comprehensive summary of the molecular mechanisms associated with hepatoblastoma occurrence, this review highlights three key aspects: genomics, epigenetics, and transcriptomics. Our review aims to facilitate the exploration of novel molecular mechanisms and the development of innovative clinical treatment strategies for hepatoblastoma.

Indocyanine green (ICG) fluorescence-enhanced applications in pediatric surgery

The breadth of pediatric surgical practice and variety of anatomic anomalies that characterize surgical disease in children and neonates require a unique level of operative mastery and versatility. Intraoperative navigation of small, complex, and often abnormal anatomy presents a particular challenge for pediatric surgeons. Clinical experience with fluorescent tissue dye, specifically indocyanine green (ICG), is quickly gaining widespread incorporation into adult surgical practice as a safe, non-toxic means of accurately visualizing tissue perfusion, lymphatic flow, and biliary anatomy to enhance operative speed, safety, and patient outcomes. Experience in pediatric surgery, however, remains limited. ICG-fluorescence guided surgery is poised to address the challenges of pediatric and neonatal operations for a growing breadth of surgical pathology. Fluorescent angiography has permitted intraoperative visualization of colorectal flap perfusion for complex pelvic reconstruction and anastomotic perfusion after esophageal atresia repair, while its hepatic absorption and biliary excretion has made it an excellent agent for delineating the dissection plane in the Kasai portoenterostomy and identifying both primary and metastatic hepatoblastoma lesions. Subcutaneous and intra-lymphatic ICG injection can identify iatrogenic chylous leaks and improved yields in sentinel lymph node biopsies. ICG-guided surgery holds promise for more widespread use in pediatric surgical conditions, and continued evaluation of efficacy will be necessary to better inform clinical practice and identify where to focus and develop this technical resource.

The effect of donor graft type on survival after liver transplantation for hepatoblastoma in children

BACKGROUND

Liver transplantation (LT) is the only potentially curative option for children with unresectable hepatoblastoma (HBL). Although post-transplant outcomes have improved in the contemporary era, the impact of donor graft type on survival remains unclear.

METHODS

Using the United Network for Organ Sharing database (02/2002-06/2021), demographics, clinical characteristics, and patient and graft survival were analyzed in children (<18 years) who underwent LT for HBL according to donor graft type. The Kaplan-Meier method, log-rank tests, and Cox regression modeling were used to evaluate the effect of whole, partial, and split deceased donor liver transplantation (DDLT) and living donor liver transplantation (LDLT) on patient and graft survival.

RESULTS

A total of 590 pediatric HBL LT recipients (344 whole graft DDLT; 62 partial graft DDLT; 139 split graft DDLT; 45 LDLT) were included. During 2012-2021 the proportion of LDLTs for HBL decreased to about 5% compared with about 11% during 2002-2011. No significant differences were identified by donor graft type in either patient survival (log-rank test, p = .45) or graft survival (log-rank test, p = .69). The results remained similar during the 2002-2011 era, while during the 2012-2021 era, split graft DDLT was associated with decreased graft loss risk versus whole graft DDLT (hazard ratio: 0.48, 95% confidence interval: 0.23-0.99, p = .046) without any other significant between-group differences.

CONCLUSIONS

Utilizing non-whole liver grafts can increase access to LT in children with unresectable HBL while ensuring favorable outcomes. LDLT is underutilized in children with HBL in the United States, and efforts to explore LDLT options should be undertaken.

Comparative Clinicopathologic and Genomic Analysis of Hepatocellular Neoplasm, Not Otherwise Specified, and Hepatoblastoma

Accurate diagnosis and treatment of hepatocellular neoplasm, not otherwise specified (HCN-NOS), poses significant challenges. Our study aimed to investigate the clinicopathologic and genomic similarities and differences between HCN-NOS and hepatoblastoma (HB) to guide diagnostic and treatment strategies. The clinicopathologic characteristics of 16 patients with HCN-NOS and 23 patients with HB were compared. Molecular studies, including the OncoKids DNA- and RNA-based next-generation sequencing panel, chromosomal microarray, and targeted Sanger sequencing analyses of CTNNB1 and TERT promoters, were employed. We found that patients with HCN-NOS were older (P < .001) and more frequently classified as high risk (P < .01), yet they showed no significant differences in alpha fetoprotein levels or survival outcomes compared with those with HB. HCN-NOS and HB had a comparable frequency of sequence variants, with CTNNB1 mutations being predominant in both groups. Notably, TERT promoter mutations (37.5%) and rare clinically significant variants (BRAF, NRAS, and KMT2D) were exclusive to HCN-NOS. HCN-NOS demonstrated a higher prevalence of gains in 1q, encompassing the MDM4 locus (17/17 vs 11/24; P < .001), as well as loss/loss of heterozygosity (LOH) of 1p (11/17 vs 6/24; P < .05) and chromosome 11 (7/17 vs 1/24; P < .01) when compared with HB. Furthermore, the recurrent loss/LOH of chromosomes 3, 4p, 9, 15q, and Y was only observed in HCN-NOS. However, no significant differences were noted in gains of chromosomes 2, 8, and 20, or loss/LOH of 4q and 11p between the 2 groups. Notably, no clinically significant gene fusions were detected in either group. In conclusion, our study reveals that HCN-NOS exhibits high-risk clinicopathologic features and greater structural complexity compared with HB. However, patients with HCN-NOS exhibit comparable alpha fetoprotein levels at diagnosis, CTNNB1 mutation rates, and survival outcomes when subjected to aggressive treatment, as compared with those with HB. These findings have the potential to enhance diagnostic accuracy and inform more effective treatments for HCN-NOS.

An update on diagnosis and treatment of hepatoblastoma

Hepatoblastoma (HB) remains the most common paediatric liver tumour and survival in children with hepatoblastoma has improved considerably since the advent of sequential surgical regimens of chemotherapy based on platinum-based chemotherapeutic agents in the 1980s. With the advent of modern diagnostic imaging and pathology techniques, new preoperative chemotherapy regimens and the maturation of surgical techniques, new diagnostic and treatment options for patients with hepatoblastoma have emerged and international collaborations are investigating the latest diagnostic approaches, chemotherapy drug combinations and surgical strategies. Diagnosis of hepatoblastoma relies on imaging studies (such as ultrasound, computed tomography, and magnetic resonance imaging), alpha-fetoprotein (AFP) levels, and histological confirmation through biopsy. The standard treatment approach involves a multimodal strategy with neoadjuvant chemotherapy followed by surgical resection. In cases where complete resection is not feasible or tumors exhibit invasive characteristics, liver transplantation is considered. The management of metastatic and recurrent hepatoblastoma poses significant challenges, and ongoing research focuses on developing targeted therapies and exploring the potential of immunotherapy. Further studies are necessary to gain a better understanding of the etiology of hepatoblastoma, develop prevention strategies, and personalize treatment approaches. We aim to review the current status of diagnosis and treatment of hepatoblastoma.

Individualized chemotherapy and efficacy analysis of hepatoblastoma in children

PURPOSE

We aimed to assess the clinical utility of the mini patient-derived xenograft (MiniPDX) model in screening individualized chemotherapy regimens for pediatric hepatoblastoma.

MATERIALS AND METHODS

We included 31 children with hepatoblastoma who had unsatisfactory decreases in alpha-fetoprotein levels during neoadjuvant chemotherapy or poor clinical control of recurrence with or without metastasis. We established a MiniPDX model using surgically resected tumor tissue specimens. The sensitivities of five chemotherapeutic regimens were tested to determine the one with the lowest tumor proliferation rate, which was then set as the experimental group. We compared the clinical characteristics and efficacy with those of conventional chemotherapy regimens.

RESULTS

The median follow-up period for the experimental group was 27 months, with a complete remission (CR) rate of 80.64%. Among stage IV cases, there was a significant between-group difference in CR rate (experimental [73.68%] vs. control [37.5%]) and 3-year event-free survival rate (79.3% vs. 26.7%). The most effective individualized chemotherapy regimens were ifosfamide + pirarubicin + etoposide + carboplatin (54.84%), followed by pirubicin + cyclophosphamide + cisplatin (16.13%), ifosfamide + carboplatin + etoposide (12.90%), cisplatin + 5-fluorouracil + vincristine + adriamycin (12.90%), and vincristine + irinotecan + cyclophosphamide + cisplatin (3.23%).

CONCLUSION

Using the MiniPDX model to screen individualized chemotherapy regimens for pediatric hepatoblastoma can significantly improve the CR rate.

PIM Kinase Inhibition Attenuates the Malignant Progression of Metastatic Hepatoblastoma

Hepatoblastoma is the most common primary pediatric liver tumor. Children with pulmonary metastases at diagnosis experience survival rates as low as 25%. We have shown PIM kinases play a role in hepatoblastoma tumorigenesis. In this study, we assessed the role of PIM kinases in metastatic hepatoblastoma. We employed the metastatic hepatoblastoma cell line, HLM_2. PIM kinase inhibition was attained using PIM3 siRNA and the pan-PIM inhibitor, AZD1208. Effects of PIM inhibition on proliferation were evaluated via growth curve. Flow cytometry determined changes in cell cycle. AlamarBlue assay assessed effects of PIM kinase inhibition and cisplatin treatment on viability. The lethal dose 50% (LD50) of each drug and combination indices (CI) were calculated and isobolograms constructed to determine synergy. PIM kinase inhibition resulted in decreased HLM_2 proliferation, likely through cell cycle arrest mediated by p21. Combination therapy with AZD1208 and cisplatin resulted in synergy, potentially through downregulation of the ataxia-telangiectasia mutated (ATM) kinase DNA damage response pathway. When assessing the combined effects of pharmacologic PIM kinase inhibition with cisplatin on HLM_2 cells, we found the agents to be synergistic, potentially through inhibition of the ATM pathway. These findings support further exploration of PIM kinase inhibition as a therapeutic strategy for metastatic hepatoblastoma.

Quantitative ctDNA Detection in Hepatoblastoma: Implications for Precision Medicine

Hepatoblastoma is characterized by driver mutations in CTNNB1, making it an attractive biomarker for a liquid biopsy approach utilizing circulating tumor DNA (ctDNA). This prospective observational study sought to ascertain the feasibility of ctDNA detection in patients with hepatoblastoma and explore its associations with established clinical indicators and biomarkers, including serum Alpha-fetoprotein (AFP). We obtained 38 plasma samples and 17 tumor samples from 20 patients with hepatoblastoma. These samples were collected at various stages: 10 at initial diagnosis, 17 during neoadjuvant chemotherapy, 6 post-operatively, and 5 at disease recurrence. Utilizing a bespoke sequencing assay we developed called QUENCH, we identified single nucleotide variants and deletions in CTNNB1 ctDNA. Our study demonstrated the capability to quantitate ctDNA down to a variant allele frequency of 0.3%, achieving a sensitivity of 90% for patients at initial diagnosis, and a specificity of 100% at the patient level. Notably, ctDNA positivity correlated with tumor burden, and ctDNA levels exhibited associations with macroscopic residual disease and treatment response. Our findings provide evidence for the utility of quantitative ctDNA detection in hepatoblastoma management. Given the distinct detection targets, ctDNA and AFP-based stratification and monitoring approaches could synergize to enhance clinical decision-making. Further research is needed to elucidate the interplay between ctDNA and AFP and determine the optimal clinical applications for both methods in risk stratification and residual disease detection.

Evaluating the clinical efficacy and limitations of indocyanine green fluorescence-guided surgery in childhood hepatoblastoma: A retrospective study

BACKGROUND

Indocyanine green (ICG) fluorescence guided surgery has been used to treat childhood hepatoblastoma (HB), but the advantages and disadvantages of this technique have not been fully discussed. The purpose of this study is to summarize the experience and to explore the clinical value of this technique for children with HB.

METHODS

45 children with HB who underwent ICG fluorescence guided surgery (n = 22) and general surgery (n = 23) in our center from January 2020 to December 2022 were enrolled retrospectively.

RESULTS

All the liver tumors in the ICG group showed hyperfluorescence, including total and partial fluorescent types. With the help of ICG navigation, minimally invasive surgery was performed in 3 cases. 18.2 % of cases with tumors could not be accurately identified under white light, but could be identified by fluorescence imaging. The fluorescent cutting lines of 59.1 % of cases were consistent with the safe cutting lines. In 36.4 % of cases, the fluorescence boundary was not clear because of tumor necrosis. In 36.4 % of cases, the fluorescence could not be detected on the inner edge of the tumors because of the depth. A total of 29 ICG (+) suspicious lesions were found during the operations, of which 5 were true positive lesions.

CONCLUSION

ICG fluorescence guided surgery is safe and feasible in children with HB. This technique is helpful for locating tumors, determining margin and finding small lesions with negative imaging, especially in minimally invasive surgery. However, preoperative chemotherapy, tumor necrosis, tumor depth, and ICG administration impact the effect of fluorescence imaging.

Navigating relapsed hepatoblastoma: Predictive factors and surgical treatment strategy

OBJECTIVE

Hepatoblastoma (HB) is the most common primary hepatic malignancy in childhood. Relapse occurs in more than 50% of high-risk patients with a high mortality due to ineffective salvage therapies. The purpose of this study is to identify risk factors for relapsed HB and predictors of survival in a single tertiary referral center.

METHODS

A retrospective chart review showed 129 surgically treated HB patients from October 2004 to July 2020. Of the cohort, 22 patients presented with relapsed HB. Relapse was defined as re-appearance of malignancy after 4 weeks of normalized AFP and disappearance of all tumors on imaging.

RESULTS

Patients with relapsed HB had a 5-year overall survival (OS) of 45.4% compared to 93.1% in those without relapse (p = 0.001). When comparing PRETEXT IV, microvascular invasion, metastatic disease, and age on multivariate logistic regression, only PRETEXT IV was an independent risk factor for relapsed HB with an OR of 2.39 (95% CI: 1.16-4.96; p = 0.019). Mixed epithelial and mesenchymal HB (12/19, 63.2%) was the most common histology of primary tumors while pure epithelial HB (13/15, 86.6%) was the most common relapsed histology. Combination of surgical and medical therapy for relapsed disease was predictive of survival with an HR of 16.3 (95% CI: 1.783-149.091; p = 0.013) compared to only chemotherapy.

CONCLUSIONS

This study demonstrates that PRETEXT IV staging is an independent predictor of relapsed disease. The most common relapsed histology was epithelial, suggesting a potential selection or resistance of this component. Surgical resection is a critical component of multimodal therapy for relapsed HB.

Review on Pediatric Malignant Focal Liver Lesions with Imaging Evaluation: Part I

Malignant focal liver lesions (FLLs) are commonly reported in adults but rarely seen in the pediatric population. Due to the rarity, the understanding of these diseases is still very limited. In children, most malignant FLLs are congenital. It is very important to choose appropriate imaging examination concerning various factors. This paper will outline common pediatric malignant FLLs, including hepatoblastoma, hepatocellular carcinoma, and cholangiocarcinoma and discuss them against the background of the latest knowledge on comparable/similar tumors in adults. Medical imaging features are of vital importance for the non-invasive diagnosis and follow-up of treatment of FLLs in pediatric patients. The use of CEUS in pediatric patients for characterizing those FLLs that remain indeterminate on conventional B mode ultrasounds may be an effective option in the future and has great potential to be integrated into imaging algorithms without the risk of exposure to ionizing radiation.

Mesenchymal hamartoma versus hepatoblastoma: A diagnostic dilemma

INTRODUCTION AND IMPORTANCE

Pediatric hepatic tumors present diagnostic challenges due to diverse clinical presentations and limited patient communication. Elevated serum alpha-fetoprotein (AFP) levels, often associated with hepatoblastoma, can occur in various hepatic conditions, adding complexity to diagnosis. This report emphasizes the importance of comprehensive assessment and integrated interpretation in such cases.

CASE PRESENTATION

We present a rare case of a 1-year-old female child with abdominal swelling and hepatomegaly. Imaging revealed a hypodense hepatic lesion with punctate calcifications. Initial biopsy suggested mesenchymal hamartoma, but subsequent biopsy confirmed hepatoblastoma, highlighting the diagnostic complexity.

CLINICAL DISCUSSION

Hepatoblastoma is the most common pediatric liver tumor, typically presenting with nonspecific symptoms. Serum AFP levels are elevated, aiding diagnosis. Imaging reveals heterogeneous, hypervascular masses. Treatment includes surgery and chemotherapy. Mesenchymal hamartoma is a rare benign tumor with variable symptoms and imaging features, emphasizing the need for histopathological confirmation. This case underscores the importance of a comprehensive diagnostic approach.

CONCLUSION

Diagnosing pediatric hepatic tumors requires an integrated assessment of clinical, laboratory, and imaging findings. Confirmatory biopsies are essential, as demonstrated by this case, where an initial diagnosis of mesenchymal hamartoma was revised to hepatoblastoma. Collaborative, multidisciplinary approaches are crucial for accurate diagnosis and effective therapeutic planning, offering hope for improved outcomes in these complex cases.

Sarcopenia as a Prognostic Factor in Patients with Hepatoblastoma: Does It Influence Surgical Outcomes and Survival? Preliminary Retrospective Study

AIM

Sarcopenia is associated with poor prognosis in adult oncologic patients, with little evidence of this association in pediatric population, including hepatoblastoma.

METHODS

Retrospective study in patients with hepatoblastoma, divided into those with or without sarcopenia. Sarcopenia was assessed by measuring psoas muscle area (PMA) at L4-L5 level on the CT/MR and defined as z-score values ≤ 2. Relapse and mortality were analyzed.

RESULTS

Twenty-one patients (57.1% male) were included, with median age 35.7 months (IQR: 23.5-58.5). Seven (33.3%) had sarcopenia on initial studies compared to 14 (66.7%) who did not. No differences were found between groups in age, weight, PRETEXT, surgical treatment or. α-fetoprotein levels. Sarcopenia was associated with a higher rate of metastases at diagnosis (49.2% vs 0.0%; p = 0.026) and surgical complications (57.1% vs 21.4%, p = 0.047). After a median follow-up of 65.1 months (1.7-144.8), 2 patients (28.6%) had tumor relapse in sarcopenic group compared to 1 (7.1%) in non-sarcopenic group. Two patients died in sarcopenic group and 1 in non-sarcopenic group. Median event-free survival (EFS) was lower in sarcopenic group (100.38 ± 25.63 vs 118.91 ± 11.52 months) as well as overall survival (OS) (101.72 ± 24.86 vs 121.78 ± 8.75 months) with no statistical significance. Five-year EFS was also lower in sarcopenic group (71% vs 93%) as well as 5-year OS (71% vs 87%).

CONCLUSIONS

Sarcopenia at diagnosis was associated with a higher rate of metastases and surgical complications in hepatoblastoma. Our data shows the first evidence of its role as a possible poor prognostic factor, influencing survival and risk of relapse.

LEVEL OF EVIDENCE

II.

TYPE OF STUDY

Original article. Retrospective study.

A Case Report and a Review of Pediatric Hepatoblastoma

Introduction

Hepatoblastoma is a rare pediatric cancer. Approximately 100 cases of hepatoblastoma are reported per year. Due to the limited incidence of this disorder an internationally agreed-upon criteria was developed to classify patients as standard or high-risk. Studies involving chemotherapeutic agents, surgery, and liver transplants have been demonstrated to improve the disease-free survival rate. The combination of chemotherapeutic agents and surgery demonstrated the ability of these regimens to downgrade the initial diagnostic staging of tumors and transform previously unresectable tumors into resectable tumors.

Case Presentation

The following case of hepatoblastoma presents a 4-year-old male who presented to the emergency department with an upper respiratory infection symptom and was found to have hepatomegaly. The patient was later classified as high-risk, unresectable hepatoblastoma.

Conclusion

Hepatoblastoma is a rare liver cancer in children with an annual incidence of 1.5 cases per million. With PRETEXT staging criterion, therapeutic options such as cisplatin/doxorubicin combination, radiotherapy, and lobectomy, have become the standard of care for this condition. Many trials have demonstrated these therapeutic options to successfully improve the survivability rate of patients affected by hepatoblastoma, downgrading tumors from advanced PRETEXT stages and enabling previously unresectable tumors to be considered resectable.

Characterisation of Aberrant Metabolic Pathways in Hepatoblastoma Using Liquid Chromatography and Tandem Mass Spectrometry (LC-MS/MS)

Hepatoblastoma (HB) is a rare childhood tumour with an evolving molecular landscape. We present the first comprehensive metabolomic analysis using untargeted and targeted liquid chromatography coupled to high-resolution tandem mass spectrometry (LC-MS/MS) of paired tumour and non-tumour surgical samples in HB patients (n = 8 pairs). This study demonstrates that the metabolomic landscape of HB is distinct from that of non-tumour (NT) liver tissue, with 35 differentially abundant metabolites mapping onto pathways such as fatty acid transport, glycolysis, the tricarboxylic acid (TCA) cycle, branched-chain amino acid degradation and glutathione synthesis. Targeted metabolomics demonstrated reduced short-chain acylcarnitines and a relative accumulation of branched-chain amino acids. Medium- and long-chain acylcarnitines in HB were similar to those in NT. The metabolomic changes reported are consistent with previously reported transcriptomic data from tumour and non-tumour samples (49 out of 54 targets) as well as metabolomic data obtained using other techniques. Gene set enrichment analysis (GSEA) from RNAseq data (n = 32 paired HB and NT samples) demonstrated a downregulation of the carnitine metabolome and immunohistochemistry showed a reduction in CPT1a (n = 15 pairs), which transports fatty acids into the mitochondria, suggesting a lack of utilisation of long-chain fatty acids in HB. Thus, our findings suggest a reduced metabolic flux in HB which is corroborated at the gene expression and protein levels. Further work could yield novel insights and new therapeutic targets.

Prognostic value of systemic inflammation response index in hepatoblastoma patients receiving preoperative neoadjuvant chemotherapy

Introduction

Inflammation is closely associated with tumor development and patient prognosis. The objective of this study is to assess the prognostic value of the preoperative inflammatory indexes in pediatric hepatoblastoma patients who receive neoadjuvant chemotherapy.

Methods

A retrospective analysis was performed on clinical and pathological data of 199 hepatoblastoma patients who underwent hepatectomy with preoperative neoadjuvant chemotherapy from January 2015 to June 2020. The receiver operating characteristic curve was used to evaluate the prognostic value of neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), systemic immune-inflammation index (SII), and systemic inflammation response index (SIRI) in predicting OS and EFS. Patients were grouped based on optimal cutoff values of preoperative inflammatory indexes. Survival rates were calculated using the Kaplan-Meier method, and survival outcomes were compared between groups using the log-rank test. Univariate and multivariate Cox proportional hazards regression models were used to identify independent prognostic factors, and a nomogram was constructed using R software to predict the probability of OS.

Results

The receiver operating characteristic curve showed prognostic value for OS, not EFS, in preoperative inflammatory indexes. Patients were categorized into low/high groups: SII ≤ 266.70/higher, NLR ≤ 1.24/higher, PLR ≤ 85.25/higher, and SIRI ≤ 0.72/higher. High NLR, PLR, SII, and SIRI groups had significantly lower 5-year OS than their low counterparts (all p-value < 0.05). The Cox analysis identified four independent prognostic factors: SIRI (HR=2.997, 95% CI: 1.119-8.031), microvascular invasion (HR=2.556, 95% CI: 1.14-5.73), the post-treatment extent of disease (POSTTEXT) staging (IV vs. I: HR=244.204, 95% CI:11.306-5274.556), and alpha-fetoprotein (>100 ng/ml: HR=0.11, 95% CI: 0.032-0.381) for hepatoblastoma patients with neoadjuvant chemotherapy. High SIRI group had more patients with adverse NLR, SII, and POSTTEXT III (all p-value < 0.05). Independent prognostic factors led to an OS nomogram with a concordance index of 0.85 (95% CI: 0.78-0.91, p-value = 1.43e-27) and the calibration curve showed a good fit between the prediction curve and the true curve.

Conclusions

SIRI is an independent prognostic factor of hepatoblastoma patients receiving neoadjuvant chemotherapy. The OS nomogram based on SIRI, POSTTEXT staging, MiVI, and AFP can be used to assess the prognosis of those patients.

Identification and experimental validation of druggable epigenetic targets in hepatoblastoma

BACKGROUND & AIMS

Hepatoblastoma (HB) is the most frequent childhood liver cancer. Patients with aggressive tumors have limited therapeutic options; therefore, a better understanding of HB pathogenesis is needed to improve treatment. HBs have a very low mutational burden; however, epigenetic alterations are increasingly recognized. We aimed to identify epigenetic regulators consistently dysregulated in HB and to evaluate the therapeutic efficacy of their targeting in clinically relevant models.

METHODS

We performed a comprehensive transcriptomic analysis of 180 epigenetic genes. Data from fetal, pediatric, adult, peritumoral (n = 72) and tumoral (n = 91) tissues were integrated. Selected epigenetic drugs were tested in HB cells. The most relevant epigenetic target identified was validated in primary HB cells, HB organoids, a patient-derived xenograft model, and a genetic mouse model. Transcriptomic, proteomic and metabolomic mechanistic analyses were performed.

RESULTS

Altered expression of genes regulating DNA methylation and histone modifications was consistently observed in association with molecular and clinical features of poor prognosis. The histone methyltransferase G9a was markedly upregulated in tumors with epigenetic and transcriptomic traits of increased malignancy. Pharmacological targeting of G9a significantly inhibited growth of HB cells, organoids and patient-derived xenografts. Development of HB induced by oncogenic forms of β-catenin and YAP1 was ablated in mice with hepatocyte-specific deletion of G9a. We observed that HBs undergo significant transcriptional rewiring in genes involved in amino acid metabolism and ribosomal biogenesis. G9a inhibition counteracted these pro-tumorigenic adaptations. Mechanistically, G9a targeting potently repressed the expression of c-MYC and ATF4, master regulators of HB metabolic reprogramming.

CONCLUSIONS

HBs display a profound dysregulation of the epigenetic machinery. Pharmacological targeting of key epigenetic effectors exposes metabolic vulnerabilities that can be leveraged to improve the treatment of these patients.

IMPACT AND IMPLICATIONS

In spite of recent advances in the management of hepatoblastoma (HB), treatment resistance and drug toxicity are still major concerns. This systematic study reveals the remarkable dysregulation in the expression of epigenetic genes in HB tissues. Through pharmacological and genetic experimental approaches, we demonstrate that the histone-lysine-methyltransferase G9a is an excellent drug target in HB, which can also be harnessed to enhance the efficacy of chemotherapy. Furthermore, our study highlights the profound pro-tumorigenic metabolic rewiring of HB cells orchestrated by G9a in coordination with the c-MYC oncogene. From a broader perspective, our findings suggest that anti-G9a therapies may also be effective in other c-MYC-dependent tumors.

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.

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.

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.

Advances in pediatric liver transplantation from the pediatric surgeon's perspective

Pediatric liver transplantation is a lifesaving state-of-the-art operation for children with various liver diseases, including cholestatic diseases, metabolic disorders, acute liver failure, and primary malignant liver tumors. Among these indications, transplantation for biliary atresia and hepatoblastoma is discussed in this review because pediatric surgeons are usually involved in their initial treatments. For biliary atresia, pediatric surgeons are advised to keep dissection of the hilar structures to a minimum during Kasai portoenterostomy in order to make total hepatectomy easier at transplantation. Early referral to a transplant team is recommended when worrisome signs of liver dysfunction, cirrhosis, portal hypertension and growth retardation are noted. Hepatoblastoma with multiplicity or located close to major vessels may indicate unresectability, and the transplant team needs to be consulted early after neoadjuvant chemotherapy is started. The graft size, including its thickness, needs to be evaluated before transplantation for small children, as tailoring the shape of the partial graft may be necessary during the transplant procedure.

TRMT61B rs4563180 G>C variant reduces hepatoblastoma risk: a case-control study of seven medical centers

N1-methyladenosine (m1A) is an essential chemical modification of RNA. Dysregulation of RNA m1A modification and m1A-related regulators is detected in several adult tumors. Whether aberrant RNA m1A modification is involved in hepatoblast carcinogenesis has not been reported. tRNA methyltransferase 61B (TRMT61B) is responsible for mitochondrial RNA m1A modification. Some evidence has shown that genetic variants of TRMT61B might contribute to cancer susceptibility; however, its roles in hepatoblastoma are unknown. This study attempted to discover novel hepatoblastoma susceptibility loci. With the TaqMan method, we examined genotypes of the TRMT61B rs4563180 G>C polymorphism among germline DNA samples from 313 cases and 1446 controls. The association of the rs4563180 G>C polymorphism with hepatoblastoma risk was estimated based on odds ratios (ORs) and 95% confidence intervals (CIs). We found that the TRMT61B rs4563180 G>C polymorphism correlated significantly with a reduction in hepatoblastoma risk (GC vs. GG: adjusted OR=0.65, 95% CI=0.49-0.85, P=0.002; GC/CC vs. GG: adjusted OR=0.66, 95% CI=0.51-0.85, P=0.002). In stratified analysis, significant associations were detected in children younger than 17 months old, girls, and subgroups with stage I+II or III+IV tumors. False-positive report probability analysis validated that children with the GC or CC genotype, particularly in those <17 months of age, had a decreased risk of hepatoblastoma. The rs4563180 G>C polymorphism also correlated with expression of TRMT61B and the nearby gene PPP1CB. We identified a high-quality biomarker measuring hepatoblastoma susceptibility, which may contribute to future screening programs.

Retreatment with Cisplatin May Provide a Survival Advantage for Children with Relapsed/Refractory Hepatoblastoma: An Institutional Experience

BACKGROUND

Hepatoblastoma (HB) is the most common liver malignancy in children. There is no standard of care for management of relapsed/refractory HB (rrHB) and reports in the literature are limited.

OBJECTIVE

To describe presenting features, biology, treatment strategies, and outcomes for pediatric patients with relapsed/refractory hepatoblastoma.

METHODS

An IRB-approved retrospective institutional review of patients with rrHB who presented for consultation and/or care from 2000-2019. Clinical, radiographic, and histologic data were collected from all patients.

RESULTS

Thirty subjects were identified with a median age of 19.5 months (range 3-169 months) at initial diagnosis and 32.5 months (range 12-194 months) at time of first relapse. 63% of subjects were male, 70% Caucasian, and 13% were born premature. Three subjects had a known cancer predisposition syndrome. Eight patients had refractory disease while 22 patients had relapsed disease. Average time from initial diagnosis to relapse or progression was 12.5 months. Average alpha-fetoprotein (AFP) at initial diagnosis was 601,203 ng/mL (range 121-2,287,251 ng/mL). Average AFP at relapse was 12,261 ng/mL (range 2.8-201,000 ng/mL). For patients with tumor sequencing (n = 17), the most common mutations were in CTNNB1 (13) and NRF2 (4). First relapse sites were lungs (n = 12), liver (n = 11) and both (n = 6). More than one relapse/progression occurred in 47% of subjects; 6 had ≥3 relapses. Pathology in patients with multiply relapsed disease was less differentiated including descriptions of small cell undifferentiated (n = 3), pleomorphic (n = 1), transitional liver cell tumor (n = 2) and HB with carcinoma features (n = 1). All subjects underwent surgical resection of site of relapsed disease with 7 subjects requiring liver transplantation. Overall survival was 50%. Survival was associated with use of cisplatin at relapse (78.6% with vs. 25% without, p = 0.012). The most common late effect was ototoxicity with at least mild sensorineural hearing loss found in 80% of subjects; 54% required hearing aids.

CONCLUSIONS

Retreatment with cisplatin at the time of relapse may provide an advantage for some patients with hepatoblastoma. Multiply relapsed disease was not uncommon and not associated with a worse prognosis. Careful attention should be paid to cumulative therapy-induced toxicity while concurrently aiming to improve cure.

An indocyanine green-based liquid biopsy test for circulating tumor cells for pediatric liver cancer

Background and Aims

Hepatoblastoma (HB) and hepatocellular carcinoma (HCC) are the most common malignant hepatocellular tumors seen in children. The aim of this work was to develop a liquid biopsy test for circulating tumor cells (CTCs) for these tumors that would be less invasive and provide information about the real-time state of tumors in response to therapies.

Methods

For this test, we utilized indocyanine green (ICG), a far-red fluorescent dye that is used clinically to identify malignant liver cells in the body during surgery. We assessed ICG accumulation in cell lines with fluorescence microscopy and flow cytometry. For our CTC test, we developed a panel of liver tumor-specific markers, ICG, Glypican-3 (GPC3), and DAPI and tested this panel with cell lines and non-cancer control blood samples. We then used this panel to analyze whole blood samples for CTC burden with a cohort of 14 HB and HCC patients and correlated with patient characteristics and outcomes.

Results

We showed that ICG accumulation is specific to liver cancer cells, compared to non-malignant liver cells, non-liver solid tumor cells, and non-malignant cells and can be used to identify liver tumor cells in a mixed population of cells. Experiments with the ICG/GPC3/DAPI panel showed that it specifically tagged malignant liver cells. With patient samples, we found that CTC burden from sequential blood samples from the same patients mirrored the patients' responses to therapy.

Conclusions

Our novel ICG-based liquid biopsy test for CTCs can be used to specifically count CTCs in the blood of pediatric liver cancer patients.

Impact and implications

This manuscript represents the first report of circulating tumor cells in the blood of pediatric liver cancer patients. The novel and innovative assay for CTCs shown in this paper will facilitate future work examining the relationship between CTC numbers and patient outcomes, forming the foundation for incorporation of liquid biopsy into routine clinical care for these patients.

Graphical abstract

Overview of novel liquid biopsy test for circulating tumor cells for pediatric liver cancer. Figure made with Biorender.

Role of Preoperative Hepatobiliary Scintigraphy in Children Requiring Liver Resection

PURPOSE

The risk of posthepatectomy liver failure (PHLF) remains an important concern following major liver resection. Assessment of future remnant liver function (FRLF) by hepatobiliary scintigraphy has shown its significance to prevent PHLF after major liver resection in adults with a threshold value of FRLF greater than 2.7%/min per m2. However, such data for pediatric patients were not published.

METHODS

A total of 77 pediatric patients with liver tumors who underwent 1-stage liver resection were included in this study. Assessment of FRLF, future remnant liver volume (FRLV), and the ratio of remnant liver volume to body weight (RLV-BWR) was performed before the surgery.

RESULTS

All patients had RLV-BWR values of more than 0.5%/kg. Future remnant liver volume values ranged from 19% to 89%, and FRLF values ranged from 1.8% to 31.8%/min per m2. Only 7 of 77 patients had FRLV values less than 25%, but their FRLF values exceeded 2.7%/min per m2. Two patients developed grade A and grade B PHLF.

CONCLUSION

Future remnant liver volume and the RLV-BWR can be used in most pediatric patients for the assessment of liver before hepatectomy. According to our data, implementation of FRLF assessment using hepatobiliary scintigraphy can be most beneficial for children with FRLV of less than 25%. The cutoff value of FRLV greater than 25% can be slightly decreased with minimal risk of developing PHLF. However, to establish a new cutoff value for FRLV in children, further prospective studies including larger numbers of patients with FRLV of less than 25% are needed.

Lung and right atrial metastases from hepatoblastoma in children: A case series and literature review

Hepatoblastoma (HB) in children with both lung and right atrial metastases is an unusual situation. The therapy for these cases is challenging and the prognosis is not good. We present three children with HB showing both lung and right atrial metastases and who underwent surgery and received preoperative/postoperative adjuvant-combined chemotherapy to achieve complete remission. Therefore, HB with lung and right atrial metastases could have a good prognosis through active and multidisciplinary treatment.

Anabolic-androgenic anabolic steroids as a probable risk factor for hepatoblastoma in infants

Key Clinical Message

The etiology of hepatoblastoma (HB) is still unknown; several risk factors have been identified. The only risk factor for the development of HB in presented case was the child's father using anabolic androgenic steroids. It may be a risk factor for developing HB in their children.

Abstract

HB is the most common primary liver cancer in children. Its etiology is still unclear. The patient's father's use of androgenic anabolic steroids could be a risk factor for developing HB in his child. A 14-month-old girl was hospitalized with intermittent fever, severe abdominal distention, and anorexia. On initial examination, she was cachectic and pale. There were two hemangioma-like skin lesions in the back. Huge hepatomegaly was found and the ultrasound showed a hepatic hemangioma. The possibility of malignancy was considered due to the severe enlargement of the liver and the increased levels of the alpha-fetoprotein. An abdominopelvic CT scan was performed and finally, the diagnosis of HB was confirmed by pathology. There was no history of congenital anomalies or risk factors for HB.Also we did not find any risk factors in the mother's history either. The only positive finding in the father's history was the use of anabolic steroids for bodybuilding. Anabolic-androgenic anabolic steroids may be one of the possible causes of HB in children.

Cisplatin in Liver Cancer Therapy

Hepatocellular carcinoma (HCC) is the most common primary liver tumor and is often diagnosed at an unresectable advanced stage. Systemic chemotherapy as well as transarterial chemoembolization (TACE) and hepatic arterial infusion chemotherapy (HAIC) are used to treat advanced HCC. TACE and HAIC have long been the standard of care for patients with unresectable HCC but are limited to the treatment of intrahepatic lesions. Systemic chemotherapy with doxorubicin or chemohormonal therapy with tamoxifen have also been considered, but neither has demonstrated survival benefits. In the treatment of unresectable advanced HCC, cisplatin is administered transhepatic arterially for local treatment. Subsequently, for cisplatin-refractory cases due to drug resistance, a shift to systemic therapy with a different mechanism of action is expected to produce new antitumor effects. Cisplatin is also used for the treatment of liver tumors other than HCC. This review summarizes the action and resistance mechanism of cisplatin and describes the treatment of the major hepatobiliary cancers for which cisplatin is used as an anticancer agent, with a focus on HCC.

Epidemiological Study of Malignant Paediatric Liver Tumours in Denmark 1985-2020

BACKGROUND

Malignant liver tumours in children are rare and national outcomes for this tumour entity are rarely published. This study mapped paediatric liver tumours in Denmark over 35 years and reported on the incidence, outcomes and long-term adverse events.

METHODS

We identified all liver tumours from the Danish Childhood Cancer Registry and reviewed the case records for patient and tumour characteristics, treatment and clinical outcome.

RESULTS

We included 79 patients in the analyses. Overall crude incidence was ~2.29 per 1 million children (<15 yr) per year, with 61 hepatoblastomas (HB), 9 hepatocellular carcinomas and 9 other hepatic tumours. Overall 5-year survival was 84%, 78% and 44%, respectively. Nine patients had underlying liver disease or predisposition syndrome. Seventeen children underwent liver transplantation, with two late complications, biliary stenosis and liver fibrosis. For HB, age ≥ 8 years and diagnosis prior to 2000 were significant predictors of a poorer outcome. Adverse events included reduced renal function in 10%, reduced cardiac function in 6% and impaired hearing function in 60% (19% needed hearing aids). Behavioural conditions requiring additional support in school were registered in 10 children.

CONCLUSIONS

In Denmark, incidences of malignant liver tumours during the last four decades have been increasing, as reported in the literature. HB survival has improved since the year 2000 and is comparable with international results. Reduced hearing is the major treatment-related side effect and affects approximately 60% of patients.

A Clinicopathological Study with Risk-Stratified Staging of Pediatric Hepatoblastoma: A 5-Year Experience from a Tertiary Cancer Center

Background & Objective

Hepatoblastoma encompasses 1% of pediatric malignancies and is the most common liver malignancy in children. Ninety percent of cases are younger than 5 years of age. Clinical and pathological risk stratification forms a crucial role in determining the treatment strategy. This study aimed to assess the clinicopathological profile of hepatoblastoma with risk stratification and follow-up in children.

Methods

A retrospective evaluation was performed on all pediatric patients diagnosed as hepatoblastoma between 2016 and 2020 in our institution. Clinical, radiological, biochemical, pathological, and treatment data were analyzed. Cases were stratified based on the SIOPEL protocol and compared with the outcome.

Results

The median age of all children was 1 year, the male-to-female ratio was 2.3:1, and elevated α-fetoprotein (AFP) was observed in all cases. SIOPEL risk stratification showed that 50% of children were at high risk. The histopathological types were fetal (30%), embryonal (20%), and macrotrabecular (5%) patterns under epithelial type and mixed epithelial and mesenchymal type (45%) with 1 case showing teratoid features. During the follow-up period, 6 out of the 7 children who died, belonged to the high-risk SIOPEL category, and 5 presented a mixed epithelial and mesenchymal pattern.

Conclusion

Our study found a significant correlation between clinicopathological data, histopathological patterns, and outcomes. Accordingly, histopathological patterns could be considered one of the criteria for risk stratification. Histopathological risk stratification indicators (such as SIOPEL and PRETEXT) have strong prognostic and predictive outcomes; hence, our study emphasizes such parameters to aid oncologists.

Imaging of pediatric liver tumors: A COG Diagnostic Imaging Committee/SPR Oncology Committee White Paper

Primary hepatic malignancies are relatively rare in the pediatric population, accounting for approximately 1%-2% of all pediatric tumors. Hepatoblastoma and hepatocellular carcinoma are the most common primary liver malignancies in children under the age of 5 years and over the age of 10 years, respectively. This paper provides consensus-based imaging recommendations for evaluation of patients with primary hepatic malignancies at diagnosis and follow-up during and after therapy.

Effectiveness of indocyanine green fluorescence imaging in resection of hepatoblastoma

OBJECTIVE

The present research aimed to analyze the application of indocyanine green (ICG) fluorescence contrast technique in the resection of hepatoblastoma (HB) in children, and to discuss the use of ICG in the surgery of HB and the value of guidance.

METHODS

We retrospectively analyzed the data of 23 children with HB resected using ICG fluorescence contrast technique at the Children's Hospital of Nanjing Medical University from June 2020 to September 2022, including 16 boys and 7 girls, aged 5 days to 80 months. The patients were administered with an ICG injection of 0.1 mg/kg around 24-48 h before surgery. The surgical margin was detected by real-time fluorescence imaging and confirmed by postoperative pathology.

RESULTS

All primary lesions showed bright fluorescence in 23 HB cases. 22 had clear borders with normal liver tissue, while one neonatal case showed no difference between tumor and background. 13 anatomic resection and 10 non-anatomic resection were performed with ICG fluorescence navigation. The surface of the residual liver was scattered with multiple tumor fluorescence, which was then locally enucleated according to the fluorescence. 22 isolated specimens were dissected and fluorescently visualized. Pathology identified deformed, vacuolated and densely arranged hepatocytes resembling pseudo-envelope changes without tumor residual, due to the compression of the tissue at the site of circumferential imaging.

CONCLUSION

The ring ICG fluorescence imaging of HB indicates the tumor resection boundary effectively, especially in multiple lesions cases.

Ribonucleotide reductase subunit switching in hepatoblastoma drug response and relapse

Prognosis of children with high-risk hepatoblastoma (HB), the most common pediatric liver cancer, remains poor. In this study, we found ribonucleotide reductase (RNR) subunit M2 (RRM2) was one of the key genes supporting cell proliferation in high-risk HB. While standard chemotherapies could effectively suppress RRM2 in HB cells, they induced a significant upregulation of the other RNR M2 subunit, RRM2B. Computational analysis revealed distinct signaling networks RRM2 and RRM2B were involved in HB patient tumors, with RRM2 supporting cell proliferation and RRM2B participating heavily in stress response pathways. Indeed, RRM2B upregulation in chemotherapy-treated HB cells promoted cell survival and subsequent relapse, during which RRM2B was gradually replaced back by RRM2. Combining an RRM2 inhibitor with chemotherapy showed an effective delaying of HB tumor relapse in vivo. Overall, our study revealed the distinct roles of the two RNR M2 subunits and their dynamic switching during HB cell proliferation and stress response.

Clinical features and a prognostic nomogram based on the SEER database for hepatoblastoma, hepatocellular carcinoma, and embryonal sarcoma among children and adolescents

BACKGROUND

Hepatoblastoma (HB), hepatocellular carcinoma (HCC), and embryonal sarcoma (ES) are the three main types of liver tumors in children and adolescents. At present, epidemiological knowledge and predictors of these three liver tumor types in multi-ethnic populations are limited. This study aimed to outline the clinical features and construct a prognostic nomogram for these tumors, which can contribute to the prediction of dynamic overall survival probability during the follow-up period.

METHODS

A total of 1,122 patients liver tumor patients between 2000 to 2019 in Surveillance, Epidemiology, and End Results (SEER) database were enrolled for the current study, and separated into 824 HB, 219 HCC, and 79 ES according to the type of pathology. Independent prognostic factors were screened by univariate and multivariate Cox regression analysis, and a prognostic nomogram was constructed for overall survival. The accuracy and discriminative abilities of the nomogram were evaluated by concordance index as well as time-dependent receiver operating characteristic curves and calibration curves.

RESULTS

Race (P=0.0016), surgery [hazard ratio (HR): 0.1021, P<0.001], and chemotherapy (HR: 0.27, P=0.00018) are independent prognostic factors for hepatoblastoma. Pathological tissue grading (P=0.00043), tumor node metastasis (TNM) staging (P=0.00061), and surgery are independent prognostic factors for hepatocellular carcinoma. Household income and surgery (HR: 0.1906, P<0.001) are independent prognostic factors for embryonal sarcoma. All of these prognostic factors are significantly associated with prognosis. A nomogram consisting of these variables was established, which showed a good concordance index (0.747, 0.775, and 0.828 in hepatoblastoma, hepatocellular carcinoma, and embryonal sarcoma, respectively). Also, the 5-year area under curve (AUC) of the nomogram were 0.738, 0.812, and 0.839 in hepatoblastoma, hepatocellular carcinoma, and embryonal sarcoma, respectively. In the calibration diagram, an optimal agreement between the nomogram-predicted and actual observed survival was evident.

CONCLUSIONS

We developed an effective prognostic nomogram for overall survival prediction in hepatoblastoma, hepatocellular carcinoma, and embryonal sarcoma in children and adolescent patients, which will further benefit the assessment of long-term outcomes.

Recent advances in surgical strategies and liver transplantation for hepatoblastoma

Hepatoblastoma (HB) is the most common malignant liver tumor in children. Although the development of treatment strategies with advances in chemotherapy has greatly improved the prognosis of HB, surgical resection and liver transplantation still play a vital role in the treatment of HB. In recent years, technological innovations have led to the development of new surgical approaches for HB. In this review, we describe the latest research on the surgical management of HB, including new imaging technologies, minimally invasive approaches, and the application of associating liver partition portal vein ligation for staged hepatectomy. We also discuss the current role of liver transplantation, use of ante-situm or ex-situ liver resection with auto-transplantation, and management of metastatic HB.