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

A narrative review of the challenges and countermeasures in hepatoblastoma management during COVID-19 epidemic

An infectious disease named "coronavirus disease 2019" (COVID-19) currently has brought a threat to global health security and trends to be more and more severe in many countries. It also has introduced great challenges to the diagnosis and management of children with hepatoblastoma (HB). During the COVID-19 pandemic, pediatric surgeons should not only develop personalized treatment plans for HB therapy, but also emphasize the diagnosis, prevention, and treatment of this virus. Children with both HB and COVID-19 are recommended to undertake multidisciplinary assessment. Anti-SARS-CoV-2 therapy may be a preferred treatment for the infected without presenting a surgical emergency. However, emergent operation may be necessary for HB children with concurrent COVID-19 who developed a life-threatening surgical emergency condition. Otherwise, for children with negative virus examination results, treatment advice should be based on the impact of the epidemic and regional economic considerations. A "wait and see" strategy is recommended for children with resectable tumors after new adjuvant chemotherapy treatment (NACT). Assessment of liver transplantation is recommended for children with HB whose tumors cannot be resected after NACT. Children with HB with pulmonary metastasis may have abnormal findings on chest imaging due to COVID-19. Besides, the detailed therapeutic regimens may vary for children with HB with or without an emergency presentation. Based on previous consensus, current research, and the experiences of our hospital, we aim to offer available management plans for the above-mentioned concerns.

Sudden and unexpected death in childhood due to an undiagnosed hepatoblastoma: Case report and review of literature

The sudden and unexpected death of an infant or child due to cancer is a particularly rare event. Most of the cases concern primary growths located in vital organs such as the heart or the brain. Only in an extremely small number of cases does it occur in infants or children affected by liver cancer. Herein we report the sudden and unexpected death of a 3-and-a-half-year-old infant, who due to an undiagnosed tumor of the liver, namely hepatoblastoma, suffered a major intra-abdominal (hemoperitoneum) bleed, leading to a fatal hemorrhagic trauma. In cases like these, it is of utmost importance to carry out both an autopsy as well as complete histological tests in order to determine if the hepatic tumor is the real cause of death or if it was a mere chance finding. In the case of sudden and unexplained deaths in infancy and childhood, the forensic pathologist should always consider that other complications, for example, those correlated with hepatoblastoma could, in fact, cause sudden death given that this particular tumor is often scarcely symptomatic and can remain undiscovered for a long period of time.

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.

Experience of treating pediatric hepatoblastoma at King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia - Timely surgical intervention playing a key role

Background

Many studies have demonstrated that outcome in patients with hepatoblastoma is determined by tumor resectability and the presence or absence of metastatic disease.

Purpose

To evaluate and disseminate information on diagnosis, treatment, and outcome of hepatoblastoma patients at a tertiary care hospital in Saudi Arabia.

Patients and methods

Twenty-four pediatric patients with hepatoblastoma were treated at our institution between January 2005 and December 2012. The majority of our patients were stage III and above, while one-third of them presented with metastatic disease. Four (16.7%) had vascular invasion. Two-thirds of our patients (n = 16, 66.7%) had alpha-fetoprotein (AFP) level above 100,000 ng/mL. Twenty-one patients underwent surgery; two had upfront surgery before getting any chemotherapy, and 15 had surgery on schedule after pre-operative chemotherapy. Four patients had delayed surgery as the tumor was not resectable and received extra cycles of chemotherapy. Chemotherapy regimens used were based on SIOPEL study protocols until 2011 and Children’s Oncology Group (COG) protocol from 2012 onwards. Relapse, progressive disease, or death from any cause were defined as events.

Results

Five-year overall survival (OS) of the cohort over a median follow-up time of 56.1 months was 70.6% ± 9.4% with seven (29.2%) events of mortality. No significant difference was found for age at diagnosis (less than 2 years vs. more), stage of disease, AFP levels (less than 100,000 vs. more), vascular invasion, or presence of metastatic disease at presentation in terms of OS. However, children receiving upfront or scheduled as-per-protocol surgery fared better than those who had delayed surgery (as the tumor was not resectable and they received extra cycles of chemotherapy) or did not undergo any surgery (P-Value .001).

Conclusion

Favorable survival outcome could be achieved with complete tumor excision and adjuvant chemotherapy. Inability to perform surgical excision was the single most important predictor of mortality in our patients.

A combined clinical and biological risk classification improves prediction of outcome in hepatoblastoma patients

AIM

Stratification of hepatoblastoma (HB) patients is based on clinical and imaging characteristics obtained at the time of diagnosis. We aim to integrate biomarkers into a tool that accurately predicts survival of HB patients.

METHODS

We retrospectively analysed 174 HB patients for the presence of four biomarkers and explored their prognostic potential by correlating with overall survival (OS) and event-free survival (EFS).

RESULTS

Mutations of CTNNB1, NFE2L2 and TERT were found in 135 (78%), 10 (6%) and 10 (6%) patients, respectively, and the adverse C2 subtype of the 16-gene signature in 63 (36%) patients. C2-patients had more frequent metastatic disease, higher alpha-fetoprotein levels, non-fetal histology and significantly worse 3-year OS (68% versus 95%) and EFS (63% versus 87%) than C1-patients. Patients carrying a NFE2L2 mutation had a significantly worse 3-year OS (57% versus 88%) than NFE2L2 wild-type patients and were more likely to have vessel invasive growth and non-fetal histology. TERT mutations were almost exclusively found in older patients, whereas CTNNB1 mutations showed no association with any clinical feature or outcome. In a multivariable analysis, the C2 subtype remained a significant predictor of poor outcome with hazard ratios of 6.202 and 3.611 for OS and EFS, respectively. When added to the Children's Hepatic tumors International Collaboration risk stratification, the presence of the C2 subtype identified a group of high-risk patients with a very poor outcome.

CONCLUSION

We propose a new stratification system based on the combination of clinical factors and the 16-gene signature, which may facilitate a risk-adapted management of HB patients.

Liver Transplantation for Colorectal and Neuroendocrine Liver Metastases and Hepatoblastoma. Working Group Report From the ILTS Transplant Oncology Consensus Conference

Liver transplantation (LT) for unresectable colorectal liver metastases has long been abandoned because of dismal prognoses. After the dark ages, advances in chemotherapy and diagnostic imaging have enabled strict patient selection, and the pioneering study from the Oslo group has contributed to the substantial progress in this field. For unresectable neuroendocrine liver metastases, LT for patients who met the Milan criteria was able to achieve excellent long-term outcomes. The guidelines further adopted in the United States and Europe were based on these criteria. For hepatoblastoma, patients with unresectable and borderline-resectable disease are considered good candidates for LT; however, the indications are yet to be defined. In the budding era of transplant oncology, it is critically important to recognize the current status and unsolved questions for each disease entity. These guidelines were developed to serve as a beacon of light for optimal patient selection for LT and set the stage for future basic and clinical studies.

WTAP Gene Variants Confer Hepatoblastoma Susceptibility: A Seven-Center Case-Control Study

Hepatoblastoma is a rare disease, and its etiology remains to be revealed. Wilms tumor suppressor-1-associated protein (WTAP) plays a critical role in tumorigenesis. However, whether single nucleotide polymorphisms (SNPs) of the WTAP gene predispose to hepatoblastoma risk awaits to be investigated. With the use of the TaqMan assay, we evaluated the genotype frequencies of three WTAP SNPs (rs7766006 G > T, rs9457712 G > A, and rs1853259 A > G) in Chinese children with 313 hepatoblastoma patients and 1,446 controls. Among these three SNPs, only the rs7766006 T allele exhibited a significant association with hepatoblastoma risk (GT versus GG: adjusted odds ratio [OR] = 0.70, 95% confidence interval [CI] = 0.53-0.92, p = 0.009; GT/TT versus GG: adjusted OR = 0.73, 95% CI = 0.57-0.95, p = 0.017). Combined analysis indicated that subjects with two risk genotypes showed significantly higher hepatoblastoma risk, compared to individuals without a risk genotype (adjusted OR = 1.38, 95% CI = 1.02-1.88, p = 0.037). The stratified analysis revealed that the rs1853259 GG genotype, the rs7766006 GT/TT genotype, and two risk genotypes modified hepatoblastoma risk in certain subgroups. The significant results were validated by haplotype analyses and false-positive report probability analyses. Furthermore, the expression quantitative trait locus analysis indicated that rs7766006 T was associated with decreased expression of WTAP mRNA. Collectively, our results suggest that WTAP SNPs may be genetic modifiers for the development of hepatoblastoma.

Prognostic analysis for children with hepatoblastoma with lung metastasis: A single-center analysis of 98 cases

AIMS

To analyze the factors affecting the prognosis of hepatoblastoma (HB) with lung metastasis in children.

METHODS

The HB patients with lung metastases admitted to Beijing Tongren Hospital, Capital Medical University were collected. The clinical data, overall results, and prognostic factors were analyzed. Multivariate analysis was done by the Cox proportional hazards model for patients' prognosis.

RESULTS

Finally, 98 HB patients (64 boys and 34 girls) with lung metastasis met the inclusion criteria, in which 64 patients had lung metastases at diagnosis (median age, 22.3 months) and 34 patients developed lung metastases while on treatment (median time, 6.5 months). The survival time and 5-year survival rate of patients with standard treatment were significantly longer than that of without standard treatment (P < .001). The survival time and 3-year survival rate had no difference between patients underwent lung metastasectomy and without lung metastasectomy (P = .099), between different diagnosis time of lung metastasis in HB patients (P = .37), between each histology type (P = .313), and different PRETEXT stage (P = .353). While the survival time and 3-year survival rate of patients with lung metastasis alone were significantly longer than that of patients with extrapulmonary involvement (P = .007). Multivariate Cox proportional hazards model revealed that the lung metastasis accompanied with extrapulmonary involvement was a risk factor affecting prognosis (HR = 0.460, 95% CI 0.239-0.888).

CONCLUSIONS

For HB children with lung metastatic, extrapulmonary involvement might be a high-risk factor of prognosis and standardized treatment with lung metastasectomy might prolong the survival time of them.

Teratoid Hepatoblastoma With Yolk Sac-Like and Neuroendocrine Elements

Teratoid hepatoblastoma (HB) is a variant of mixed HB described as having a mixture of heterologous components. A 3-year-old boy presented for a liver transplant evaluation due to persistent HB. His liver was biopsied as well as a perirenal mass. Histologic examination demonstrated elements of yolk sac tumor and review of original resection showed a neuroendocrine component. This unique combination of histology has not been reported before in HB. Also, this case presents a unique diagnostic challenge as it presented with a metastasis containing yolk sac elements. Recognition and awareness of this histologic variant are important to accurately identify metastatic lesions.

Successful use of transarterial radioembolization with yttrium-90 (TARE-Y90) in two children with hepatoblastoma

Primary malignant liver tumors are rare but all require surgical resection as part of therapy with curative intent. A minority of patients have resectable tumors at diagnosis. Chemotherapy has a therapeutic role in hepatoblastoma but only one-third of patients have resectable disease at diagnosis. Two children with hepatoblastoma and suboptimal responses to initial chemotherapy received therapy with transarterial radioembolization utilizing yttrium-90 (TARE-Y90) and had significant response leading to resection and remission. The role of TARE-Y90 needs to be studied further to define its use in primary pediatric liver neoplasms.

SP8 Promotes an Aggressive Phenotype in Hepatoblastoma via FGF8 Activation

Hepatoblastoma (HB) is the most common malignant liver tumor in childhood and it generally has a good prognosis. However, if associated with aggressive metastatic disease, outcome is still poor. The molecular mechanisms leading to metastatic spread in HB patients are still unknown. By combining RNA-sequencing and a genome-wide methylome analysis, we identified the transcription factor SP8 and the growth factor FGF8 among the most strongly upregulated genes in metastatic HB cases, with a concomitant robust demethylation of the respective promoter regions. Of note, high expression of both candidates was associated with the aggressive C2 subtype of the 16-gene signature and poor survival. Chromatin immunoprecipitation revealed a direct transcriptional regulation of FGF8 through binding of SP8 to the FGF8 promoter. Gain- and loss-of-function experiments proved promoting effects of SP8 on motility, self-renewal, migration, and the invasive potential of HB cells. Moreover, stable overexpression of SP8 in Hep3B cells resulted in the acquisition of a mesenchymal phenotype and a strong upregulation of epithelial-mesenchymal transition-associated genes. Using KRAB-mediated CRISPR-dCas9 interference directed against FGF8, we could show that FGF8 is essential for the SP8-mediated aggressive tumor behavior. Treatment of HB cell lines with the pan SP family inhibitor mithramycin A resulted in a significant inhibition of their clonogenic growth. In summary, we identified SP8 and FGF8 as key players in aggressive traits of HB and propose SP8 inhibiting drugs as a new effective treatment strategy especially for metastatic tumors.

Clinical risk stratification of children with SIOPEL high-risk hepatoblastoma in Taiwan

BACKGORUND

Hepatoblastoma is the most common primary liver malignancy in young children.

METHODS

To identify predictors of the clinical outcomes of hepatoblastoma, we retrospectively reviewed the medical records of 45 children with hepatoblastoma in the National Taiwan University Hospital from 1998 to 2018. All of the children were classified as high risk according to the pretreatment extent of disease (PRETEXT) staging system. The patients' clinical data (sex, age at diagnosis, PRETEXT status, presence of metastasis or tumor rupture, tumor pathologic type, and clinical outcomes) were analyzed.

RESULTS

A total of 45 children with high-risk hepatoblastoma were diagnosed at an average age of 3.2 years. The survival analysis showed that the event-free survival duration was significantly longer in patients aged ≤1.25 years at diagnosis than those >1.25 years (hazard ratio = 2.86, p = 0.036). The absence of initial tumor rupture was associated with longer event-free survival (hazard ratio = 2.74, p = 0.039). Diagnosis at age >1.25 years was correlated with the presence of multifocal liver tumors (p = 0.0002) and tumor rupture at diagnosis (p = 0.02). There was no significant difference in event-free survival between the groups classified as intermediate versus high risk according to the Children's Hepatic tumors International Collaboration hepatoblastoma stratification system (p = 0.13).

CONCLUSIONS

Diagnosis at ≤ 1.25 years of age and absence of initial tumor rupture were predictive of a good clinical prognosis in Taiwanese children with hepatoblastoma.

Epigenetic footprint enables molecular risk stratification of hepatoblastoma with clinical implications

BACKGROUND & AIMS

Hepatoblastoma (HB) is a rare disease. Nevertheless, it is the predominant pediatric liver cancer, with limited therapeutic options for patients with aggressive tumors. Herein, we aimed to uncover the mechanisms of HB pathobiology and to identify new biomarkers and therapeutic targets in a move towards precision medicine for patients with advanced HB.

METHODS

We performed a comprehensive genomic, transcriptomic and epigenomic characterization of 159 clinically annotated samples from 113 patients with HB, using high-throughput technologies.

RESULTS

We discovered a widespread epigenetic footprint of HB that includes hyperediting of the tumor suppressor BLCAP concomitant with a genome-wide dysregulation of RNA editing and the overexpression of mainly non-coding genes of the oncogenic 14q32 DLK1-DIO3 locus. By unsupervised analysis, we identified 2 epigenomic clusters (Epi-CA, Epi-CB) with distinct degrees of DNA hypomethylation and CpG island hypermethylation that are associated with the C1/C2/C2B transcriptomic subtypes. Based on these findings, we defined the first molecular risk stratification of HB (MRS-HB), which encompasses 3 main prognostic categories and improves the current clinical risk stratification approach. The MRS-3 category (28%), defined by strong 14q32 locus expression and Epi-CB methylation features, was characterized by CTNNB1 and NFE2L2 mutations, a progenitor-like phenotype and clinical aggressiveness. Finally, we identified choline kinase alpha as a promising therapeutic target for intermediate and high-risk HBs, as its inhibition in HB cell lines and patient-derived xenografts strongly abrogated tumor growth.

CONCLUSIONS

These findings provide a detailed insight into the molecular features of HB and could be used to improve current clinical stratification approaches and to develop treatments for patients with HB.

LAY SUMMARY

Hepatoblastoma is a rare childhood liver cancer that has been understudied. We have used cutting-edge technologies to expand our molecular knowledge of this cancer. Our biological findings can be used to improve clinical management and pave the way for the development of novel therapies for this cancer.

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

PURPOSE

Treatment outcomes for hepatoblastoma have improved markedly in the contemporary treatment era, principally due to therapy intensification, with overall survival increasing from 35% in the 1970s to 90% at present. Unfortunately, these advancements are accompanied by an increased incidence of toxicities. A detailed analysis of age as a prognostic factor may support individualized risk-based therapy stratification.

METHODS

We evaluated 1605 patients with hepatoblastoma included in the CHIC database to assess the relationship between event-free survival (EFS) and age at diagnosis. Further analysis included the age distribution of additional risk factors and the interaction of age with other known prognostic factors.

RESULTS

Risk for an event increases progressively with increasing age at diagnosis. This pattern could not be attributed to the differential distribution of other known risk factors across age. Newborns and infants are not at increased risk of treatment failure. The interaction between age and other adverse risk factors demonstrates an attenuation of prognostic relevance with increasing age in the following categories: metastatic disease, AFP < 100 ng/mL, and tumor rupture.

CONCLUSION

Risk for an event increased with advancing age at diagnosis. Increased age attenuates the prognostic influence of metastatic disease, low AFP, and tumor rupture. Age could be used to modify recommended chemotherapy intensity.

Imaging and Pathology Study of the Chemotherapy Regression Area of Hepatoblastoma - A Prospective Single-Center Study

Objective: The objective of this study is to determine the frequency of no residual cancer tissue in the chemotherapy regression area (CRA) of hepatoblastoma after preoperative chemotherapy and to measure the distance between the tumor capsule and the residual cancer nests. Methods: All the tissues in the CRAs of the resected specimens were excised. HE staining and immunohistochemical staining were performed to determine the frequency of residual cancer tissue in the CRA, and the distances between the residual cancer nests and the tumor capsule were measured. Results: A total of 30 patients were included in the study. The tumor volume decreased after chemotherapy by an average of 619 ml. Of the 30 patients, the CRAs of 18 still had residual cancer nests. The longest distance between the residual cancer nest and tumor capsule was 11.2 mm. Conclusions: After chemotherapy, 60% of patients still had residual cancer nests in CRAs, the furthest distance was 11.2 mm.

Computed tomography imaging and clinical features of congenital hepatoblastoma: A retrospective analysis

Congenital hepatoblastoma (CHB) is the most common hepatic malignant tumor of fetus or neonates, but few studies focusing on the radiological characteristics of CHB have been reported to date.To investigate the characteristic clinical and computed tomography (CT) findings of CHB to facilitate recognition and noninvasive diagnosis.Medical records of 7 patients with CHB were retrospectively reviewed. The demographic, clinical, and laboratory data were extracted from the electronic medical records. Two pediatric radiologists evaluated the abdominal CT examinations for the hepatic tumor location, size, enhancement characteristics, vascular invasion, and intra-/extra-hepatic metastasis.Among the included 7 patients (3 males and 4 females), only 1 had an elevated serum alpha-fetoprotein level. All patients had solitary intrahepatic mass with a mean size of 4.7 cm (range: 2.9-10.2 cm), of which liver SV-VII were most involved. 4/7 tumors were round while 3/7 irregular or lobulated. 6/7 tumors were well-defined. Microhemorrhage, cystic necrosis, and coarse calcification were present in 5/7, 4/7, and 1/7 tumors, respectively. All lesions showed inhomogeneously significant enhancement, with multiple nodular or striped appearance in the center and periphery of the tumors on the arterial phase, and then the enhancement area showed progressive expansion and fusion filling over time but the attenuation gradually declined on the portal and delayed phases, and finally the majority (6/7) of tumors presented multiple band- or island-like characteristics with prominently peripheral enhancement on the delayed phase while the remaining 1 relatively small tumor showed nearly complete but inhomogenous enhancement. In addition, only 1/7 tumor had hilar hepatic bile duct and portal vein invasion and secondary intra-hepatic bile duct dilation. No metastatic lesions were identified in all patients at diagnosis. The abdominal aorta distal to the coeliac trunk was significantly narrowed in 3/7 patients. Pathological examinations suggested that 6/7 tumors showed fetal histology with only 1 containing mesenchymal elements.The relationship between serum alpha-fetoprotein and CHB could be more complicated and yet to be determined. Dynamic contrast-enhanced CT can facilitate recognition and noninvasive diagnosis of CHB, presenting a pattern of progressive expansion and fusion filling but inhomogeneously significant enhancement.

Hepatoblastoma: current knowledge and promises from preclinical studies

The survival rate for patients with metastatic hepatoblastoma (HB) is steadily increased in the last thirty years from 27% to 79%. These achievements result from accurate risk stratification and effective chemotherapy and surgical care. However, patients with poor prognosis require more effective therapies. Recent years have witnessed new insights on the biology of HB, setting the stage for molecular classification and new targets of therapy. We review here the molecular pathology of HB, focusing on the driver genes involved in the process of oncogenesis and the identification of novel targets. We also address the role of in vivo models in elucidating the mechanisms of development of this disease and the pre-clinical phase of new treatment modalities.

Association of TP53 rs1042522 C>G and miR-34b/c rs4938723 T>C polymorphisms with hepatoblastoma susceptibility: A seven-center case-control study

BACKGROUND

Hepatoblastoma is a rare malignancy originating from pluripotent stem cells with unknown etiology. An understanding of the etiology in pediatric hepatoblastoma has been hampered by the unavailability of sufficient patient samples. To date, only a few epidemiological studies with small sample sizes have been performed investigating risk factors for hepatoblastoma. TP53 and pri-miR-34b/c genes are implicated in the tumorigenesis, yet the role of their polymorphisms in hepatoblastoma susceptibility remains unknown.

METHODS

We conducted a seven-center case-control study to explore the genetic variants predisposing to hepatoblastoma susceptibility. In our study, we genotyped two functional polymorphisms, the TP53 rs1042522 C>G (Arg72Pro) and miR-34b/c rs4938723 T>C, in 313 cases and 1446 controls using the TaqMan method.

RESULTS

Single loci analysis showed that neither TP53 rs1042522 C>G, nor miR-34b/c rs4938723 T>C significantly modified hepatoblastoma risk. In the stratification analysis, we identified that the miR-34b/c rs4938723 TC/CC genotypes were associated with a decreased risk in patients with clinical stages III + IV hepatoblastoma (adjusted odds ratio = 0.53, 95% confidence interval = 0.33-0.84, P=0.007] compared to the rs4938723 TT genotype. Subsequent analysis further showed that the combination of TP53 and miR-34b/c variant genotypes had no impact on susceptibility hepatoblastoma.

CONCLUSIONS

Taken together, TP53 rs1042522 C>G and miR-34b/c rs4938723 T>C may not confer hepatoblastoma susceptibility. These findings may aid in our understanding of the genetic etiology of hepatoblastoma.

Peroxiredoxin 4 promotes embryonal hepatoblastoma cell migration but induces fetal cell differentiation

Hepatoblastoma (HB) is the leading primary hepatic malignancy in children and likely emerges due to failure of hepatic progenitor cells to properly differentiate. The peroxiredoxin (PRDX) family is frequently linked to cancer. In our previous study, we demonstrated that expression of the only secreted family member, PRDX4, was correlated with hepatocellular carcinoma. The aim of this new study was to investigate PRDX4's role in HB. We collected 87 HB specimens and performed PRDX4 immunohistochemistry staining. Clinical analysis was conducted and the effect of PRDX4 overexpression on two HB cell lines (Huh6 and HepG2) was also examined. Clinical data revealed elevated PRDX4 expression in embryonal component was correlated with advanced stage (IV) and metastasis. In comparison, increased PRDX4 expression in fetal component was associated with well differentiation. In vitro experiments showed PRDX4 overexpression enhanced migration in embryonal-like HB cells (Huh6), which was accompanied by epithelial-mesenchymal transition (EMT). By contrast, PRDX4 overexpression inhibited proliferation, decreased stemness markers, and increased hepatic markers in fetal-like HB cells (HepG2), which indicated induction of tumor cell differentiation. In conclusion, PRDX4 promotes embryonal hepatoblastoma cell migration but induces fetal cell differentiation. It can be adopted as an important marker for HB prognosis and a potential treatment target.

Transcription activation of circ-STAT3 induced by Gli2 promotes the progression of hepatoblastoma via acting as a sponge for miR-29a/b/c-3p to upregulate STAT3/Gli2

BACKGROUND

Hepatoblastoma (HB) is a common liver malignancy in children. Our previous study has disclosed the crucial role of STAT3 (signal transducer and activator of transcription 3) in HB.

AIM OF THE STUDY

Present study was designed to study the circular RNA (circRNA) STAT3 in HB.

METHODS

Gel electrophoresis revealed the circular characteristics of circ-STAT3. Function assays like EdU, transwell and sphere formation assay disclosed the function of circ-STAT3 in HB cells. Mechanism assays including ChIP, RIP, RNA pull down assay demonstrated the macular mechanism underlying circ-STAT3.

RESULTS

Circ_0043800, which was originated from STAT3, was up-regulated in HB tissues and cells. More importantly, silencing of circ-STAT3 led to the inhibition on HB cell growth, migration and stem-cell characteristics. Circ_0043800 was predominantly located in the cytoplasm of HB cells. Then, circ_0043800 was found to up-regulate STAT3 via sponging miR-29a/b/c-3p. Besides, we identified that STAT3 overexpression partially rescued silenced circ_0043800, while miR-29a/b/c-3p inhibition completely rescued silenced circ_0043800 on HB cellular biological behaviors. Subsequently, Gli2 (GLI family zinc finger 2) was identified as another target of miR-29a/b/c-3p. Circ_0043800 served as a competing endogenous RNA (ceRNA) to up-regulate both Gli2 and STAT3 via sponging miR-29a/b/c-3p. Moreover, we figured out that Gli2 overexpression completely rescued silenced circ_0043800 on HB cell malignant behaviors. After that, we discovered that Gli2 transcriptionally activated circ_0043800. The in-vivo assays further revealed that circ_0043800 promoted HB tumor growth by up-regulation of Gli2 and STAT3.

CONCLUSION

Gli2-induced circ_0043800 served as the ceRNA to promote HB by up-regulation of STAT3 and Gli2 at a miR-29a/b/c-3p dependent manner.

Surgical Therapy for Pediatric Hepatoblastoma in the USA over the Last Decade: Analysis of the National Cancer Database

INTRODUCTION

Hepatoblastoma (HB) is a rare childhood malignancy with hepatic resection (HR) or liver transplantation (LT) providing the best chance of cure. In this study, we analyze the National Cancer Database lacks (NCDB) to compare outcomes following HR and LT for HB.

METHODS

Review of the US experience with surgical (HR and LT) management of pediatric (< 18 years) HB over the last decade (2004-2014) using data extracted from the NCDB.

RESULTS

A total of 628 children underwent surgical treatment for HB during the study period: HR in 525 (83.6%) and LT in 103 (16.4%). The two groups were comparable for age, sex, race, tumor size, and metastatic disease at initial diagnosis. LT group had significantly higher number of patients with bilobar disease (40 vs 21%; p < 0.001), longer median time from diagnosis to surgery (120 vs 78 days; p < 0.001), and longer post-operative length of stay (LOS) (14 vs 6 days; p < 0.001). There were no differences in rates of 30-day readmission and 30- or 90-day mortality between groups. Both groups had comparable 5-year overall survival (OS) (84.1% HR vs 80.0% LT; p = 0.4). Univariate analysis identified metastatic disease at initial presentation (HR 2.56, CI 1.51-4.35) and age ≥ 4 years (HR 2.68, CI 1.5-4.7) as risk factors for worse overall 5-yr OS, while administration of adjuvant chemotherapy was associated with improved 5-yr OS (92.3% with chemo vs 85.4% without chemo; HR 0.51, CI 0.31-0.84).

CONCLUSION

The outcome of HB has improved compared with historical controls. Age at presentation, metastatic disease, and post-operative chemotherapy impact outcomes.

Outcome and Late Complications of Hepatoblastomas Treated Using the Japanese Study Group for Pediatric Liver Tumor 2 Protocol

PURPOSE

We report here the outcomes and late effects of the Japanese Study Group for Pediatric Liver Tumors (JPLT)-2 protocol, on the basis of cisplatin-tetrahydropyranyl-adriamycin (CITA) with risk stratification according to the pretreatment extent of disease (PRETEXT) classification for hepatoblastoma (HB).

PATIENTS AND METHODS

From 1999 to 2012, 361 patients with untreated HB were enrolled. PRETEXT I/II patients were treated with up-front resection, followed by low-dose CITA (stratum 1) or received low-dose CITA, followed by surgery and postoperative chemotherapy (stratum 2). In the remaining patients, after 2 cycles of CITA, responders received the CITA regimen before resection (stratum 3), and nonresponders were switched to ifosfamide, pirarubicin, etoposide, and carboplatin (ITEC; stratum 4). Intensified chemotherapeutic regimens with autologous hematopoietic stem-cell transplantation (SCT) after resection were an optional treatment for patients with refractory/metastatic disease.

RESULTS

The 5-year event-free and overall survival rates of HB patients were 74.2% and 89.9%, respectively, for stratum 1, 84.8% and 90.8%%, respectively, for stratum 2, 71.6% and 85.9%%, respectively, for stratum 3, and 59.1% and 67.3%%, respectively, for stratum 4. The outcomes for CITA responders were significantly better than those for nonresponders, whose outcomes remained poor despite salvage therapy with a second-line ITEC regimen or SCT. The late effects, ototoxicity, cardiotoxicity, and delayed growth, occurred in 61, 18, and 47 patients, respectively. Thirteen secondary malignant neoplasms (SMNs), including 10 leukemia, occurred, correlating with higher exposure to pirarubicin and younger age at diagnosis.

CONCLUSION

The JPLT-2 protocol achieved up-front resectability in PRETEXT I/II patients with no annotation factors, and satisfactory survival in patients who were CITA responders in the remaining patients. However, outcomes for CITA nonresponders were unsatisfactory, despite therapy intensification with ITEC regimens and SCT. JPLT-2 had a relatively low incidence of cardiotoxicity but high rates of SMNs.

Outcomes of children with hepatoblastoma who underwent liver resection at a tertiary hospital in China: a retrospective analysis

BACKGROUND

To report the outcomes of hepatoblastoma resected in our institution.

METHODS

We diagnosed 135 children with hepatoblastoma at our institution between January 2010 and December 2017. Patients who underwent liver resection were included for analysis. However, patients who abandoned treatment after diagnosis were excluded from analysis, but their clinical characteristics were provided in the supplementary material.

RESULTS

Forty-two patients abandoned treatment, whereas 93 patients underwent liver resection and were included for statistical analysis. Thirty-six, 23, 3, and 31 patients had PRETEXT stages II, III, IV, and unspecified tumours, respectively. Seven patients had ruptured tumour; 9 had lung metastasis (one patient had portal vein thrombosis concurrently). Sixteen patients underwent primary liver resection; 22, 25, and 30 patients received cisplatin-based neoadjuvant chemotherapy and delayed surgery, preoperative transarterial chemoembolization (TACE) and delayed surgery, and a combination of cisplatin-based neoadjuvant chemotherapy, TACE, and delayed surgery, respectively. Forty patients had both PRETEXT and POST-TEXT information available for analysis. Twelve patients were down-staged after preoperative treatment, including 2, 8, and 2 patients from stages IV to III, III to II, and II to I, respectively. Ten patients with unspecified PRETEXT stage were confirmed to have POST-TEXT stages II (n = 8) and I (n = 2) tumours. Seven tumours were associated with positive surgical margins, and 12 patients had microvascular involvement. During a median follow-up period of 30.5 months, 84 patients survived without relapse, 9 experienced tumour recurrence, and 4 died. The 2-year event-free survival (EFS) and overall survival (OS) rates were 89.4 ± 3.4%, and 95.2 ± 2.4%, respectively; they were significantly better among patients without metastasis (no metastasis vs metastasis: EFS, 93.5 ± 3.7% vs 46.7 ± 19.0%, adjusted p = 0.002. OS, 97.6 ± 2.4% vs 61.0 ± 18.1%, adjusted p = 0.005), and similar among patients treated with different preoperative strategies (chemotherapy only vs TACE only vs Both: EFS, 94.7 ± 5.1% vs 91.7 ± 5.6% vs 85.6 ± 6.7%, p = 0.542. OS, 94.1 ± 5.7% vs 95.7 ± 4.3% vs 96.7 ± 3.3%, p = 0.845).

CONCLUSION

The OS for patients with hepatoblastoma who underwent liver resection was satisfactory. Neoadjuvant chemotherapy and TACE seemed to have a similar effect on OS. However, the abandonment of treatment by patients with hepatoblastoma was common, and may have biased our results.

Inhibition of Aurora Kinase A by Alisertib Reduces Cell Proliferation and Induces Apoptosis and Autophagy in HuH-6 Human Hepatoblastoma Cells

Purpose

Aurora kinase A (AURKA), which belongs to the serine/threonine protein kinase family, has been identified as a key driver of the genesis and progression of diverse tumors. The aim of this study was to determine the clinical significance of AURKA in patients with hepatoblastoma (HB) and the effect of inhibiting AURKA in the HB cell line HuH-6.

Methods

The expression of AURKA in HB tissue and adjacent normal liver tissue was detected by immunohistochemistry. Then, statistical analysis was performed to evaluate the association between AURKA expression and the clinicopathological characteristics of HB. The effect of AURKA knockdown on cell viability was assessed by CCK-8 assay. EdU and CCK-8 assays, Western blotting, flow cytometry, and transmission electron microscopy (TEM) were used to examine the effect of alisertib (ALS), a selective AURKA small-molecule inhibitor, on the cell cycle, proliferation, apoptosis, and autophagy in HuH-6 human hepatoblastoma cells.

Results

The expression of AURKA was significantly higher in HB tissue than in adjacent normal tissue. Furthermore, high AURKA expression was associated with advanced Children’s Oncology Group (COG) stage and tumor metastasis of HB. In vitro, AURKA knockdown significantly reduced the viability of HuH-6 cells, while ALS treatment significantly suppressed HuH-6 cell proliferation and induced G1-phase cell cycle arrest by reducing cyclin-D1 expression. Moreover, ALS promoted apoptosis and autophagy by decreasing the activity of p38 MAPK in HuH-6 cells.

Conclusion

High expression of AURKA is a potential predictor of poor prognosis in HB patients. AURKA knockdown reduced the viability of HuH-6 cells, and ALS treatment inhibited cell proliferation and induced apoptosis and autophagy via the p38 MAPK signaling pathway. Our results suggest that AURKA may be a novel therapeutic target and ALS a potential therapeutic drug for the treatment of HB.

Outcomes for high-risk hepatoblastoma in a resource-challenged setting

Background

Outcomes of high‐risk hepatoblastoma have been dismal, especially in resource‐challenged countries where access to chemotherapy and paediatric liver transplantation is limited for the underprivileged. This study aimed to assess the results of treatment of high‐risk hepatoblastoma in a tertiary centre, including patients who had non‐transplant surgical procedures in the form of extended resection.

Methods

A review of patients with high‐risk hepatoblastoma treated between January 2012 and May 2018 was carried out. Perioperative data and long‐term outcomes were analysed.

Results

Of 52 children with hepatoblastoma, 22 were considered to have high‐risk hepatoblastoma (8 girls and 14 boys). The mean(s.d.) age at diagnosis was 35(20) months. Of these 22 children, five died without surgery. Of the remaining 17 who underwent surgery, six had a resection (4 right and 2 left trisectionectomies) and 11 underwent living‐donor liver transplantation. Median follow‐up was 48 (range 12–90) months. Thirteen of the 17 children were alive at last follow‐up and four developed disseminated disease (3 had undergone liver transplantation and 1 liver resection). The overall survival rate at 1, 3 and 5 years was 77, 64 and 62 per cent for the whole cohort with high‐risk hepatoblastoma. In children who had surgery, 1‐, 3‐ and 5‐year survival rates were 91, 82 and 73 per cent for transplantation and 100, 83 and 83 per cent for resection. There was no difference in survival between the two surgical groups.

Conclusion

Excellent results in the treatment of high‐risk hepatoblastoma are possible, even in resource‐challenged countries.

Insights Into the Somatic Mutation Burden of Hepatoblastomas From Brazilian Patients

Hepatoblastoma is a very rare embryonal liver cancer supposed to arise from the impairment of hepatocyte differentiation during embryogenesis. In this study, we investigated by exome sequencing the burden of somatic mutations in a cohort of 10 hepatoblastomas, including a congenital case. Our data disclosed a low mutational background and pointed out to a novel set of candidate genes for hepatoblastoma biology, which were shown to impact gene expression levels. Only three recurrently mutated genes were detected: CTNNB1 and two novel candidates, CX3CL1 and CEP164. A relevant finding was the identification of a recurrent mutation (A235G) in two hepatoblastomas at the CX3CL1 gene; evaluation of RNA and protein expression revealed upregulation of CX3CL1 in tumors. The analysis was replicated in two independents cohorts, substantiating that an activation of the CX3CL1/CX3CR1 pathway occurs in hepatoblastomas. In inflammatory regions of hepatoblastomas, CX3CL1/CX3CR1 were not detected in the infiltrated lymphocytes, in which they should be expressed in normal conditions, whereas necrotic regions exhibited negative labeling in tumor cells, but strongly positive infiltrated lymphocytes. Altogether, these data suggested that CX3CL1/CX3CR1 upregulation may be a common feature of hepatoblastomas, potentially related to chemotherapy response and progression. In addition, three mutational signatures were identified in hepatoblastomas, two of them with predominance of either the COSMIC signatures 1 and 6, found in all cancer types, or the COSMIC signature 29, mostly related to tobacco chewing habit; a third novel mutational signature presented an unspecific pattern with an increase of C>A mutations. Overall, we present here novel candidate genes for hepatoblastoma, with evidence that CX3CL1/CX3CR1 chemokine signaling pathway is likely involved with progression, besides reporting specific mutational signatures.

The Hippo Effector Transcriptional Coactivator with PDZ-Binding Motif Cooperates with Oncogenic β-Catenin to Induce Hepatoblastoma Development in Mice and Humans

Hepatoblastoma (HB) is the most common pediatric liver tumor. Though Wnt/β-catenin and Hippo cascades are implicated in HB development, studies on crosstalk between β-catenin and Hippo downstream effector transcriptional coactivator with PDZ-binding motif (TAZ) in HB are lacking. Expression levels of TAZ and β-catenin in human HB specimens were assessed by immunohistochemistry. Functional interplay between TAZ and β-catenin was determined by overexpression of an activated form of TAZ (TAZS89A), either alone or combined with an oncogenic form of β-catenin (ΔN90-β-catenin), in mouse liver via hydrodynamic transfection. Activation of TAZ often co-occurred with that of β-catenin in clinical specimens. Although the overexpression of TAZS89A alone did not induce hepatocarcinogenesis, concomitant overexpression of TAZS89A and ΔN90-β-catenin triggered the development of HB lesions exhibiting both epithelial and mesenchymal features. Mechanistically, TAZ/β-catenin-driven HB development required TAZ interaction with transcriptional enhanced associate domain factors. Blockade of the Notch cascade did not inhibit TAZ/β-catenin-dependent HB formation in mice but suppressed the mesenchymal phenotype. Neither Yes-associated protein nor heat shock factor 1 depletion affected HB development in TAZ/β-catenin mice. In human HB cell lines, silencing of TAZ resulted in decreased cell growth, which was further reduced when TAZ knockdown was associated with suppression of either β-catenin or Yes-associated protein. Overall, our study identified TAZ as a crucial oncogene in HB development and progression.

Liver Transplantation for Pediatric Liver Cancer

Unresectable hepatocellular carcinoma (HCC) was first removed successfully with total hepatectomy and liver transplantation (LT) in a child over five decades ago. Since then, children with unresectable liver cancer have benefitted greatly from LT and a confluence of several equally important endeavors. Regional and trans-continental collaborations have accelerated the development and standardization of chemotherapy regimens, which provide disease control to enable LT, and also serve as a test of unresectability. In the process, tumor histology, imaging protocols, and tumor staging have also matured to better assess response and LT candidacy. Significant trends include a steady increase in the incidence of and use of LT for hepatoblastoma, and a significant improvement in survival after LT for HCC with each decade. Although LT is curative for most unresectable primary liver sarcomas, such as embryonal sarcoma, the malignant rhabdoid tumor appears relapse-prone despite chemotherapy and LT. Pediatric liver tumors remain rare, and diagnostic uncertainty in some settings can potentially delay treatment or lead to the selection of less effective chemotherapy. We review the current knowledge relevant to diagnosis, LT candidacy, and post-transplant outcomes for these tumors, emphasizing recent observations made from large registries or larger series.

Clinical and Pathological Study of Tumor Border Invasion-Is Narrow Resection Margin Acceptable in Hepatoblastoma Surgery?

Aim: We aim to study clinically and pathologically whether narrow resection margin (<1 cm) is acceptable in hepatoblastoma surgery.

Methods: A total of 42 patients who underwent surgery for hepatoblastoma were selected, and these patients were divided into two groups according to whether or not they underwent preoperative chemotherapy (CHT). The general characteristics of the patients were summarized, the resection margin distance was recorded, and the event-free survival rates were followed up. Pathologically, H&E staining and immunochemical staining were used to study the invasion distance outside the tumor capsule in the tumor border.

Results: Clinically, the event-free survival rates were not significantly different between the patients with wide resection margin (>1 cm) and narrow resection margin (<1 cm) of the two groups. Pathologically, the tumor of all 42 patients had capsules surrounding the tumor. Of the patients in Group 1 (without preoperative CHT), 9% (2/22) had micrometastatic cancer nests outside the capsule, and the farthest distance from the cancer nests to the capsule was 4.6 mm. Of the patients in Group 2 (with preoperative CHT), 75% (15/20) showed residual cancer nests in the paratumor liver tissue, and the farthest distance was 9.6 mm; three and two cases, respectively, showed extracapsular intravascular microtumorous thrombi.

Conclusion: Clinically and pathologically, narrow resection margin is acceptable in hepatoblastoma surgery.

Novel treatment of refractory / recurrent pulmonary hepatoblastoma

BACKGROUND

There is no consensus about how to manage pulmonary metastasis in patients with hepatoblastoma. We reviewed a treatment with a combination of oxaliplatin, vincristine, and topotecan (OVT) paired with radiofrequency ablation (RFA) of 12 patients with multiple refractory / recurrent pulmonary hepatoblastoma.

METHODS

The medical records from patients with ≤21 years of age presenting with multiple deposits (≥2) of refractory / recurrent pulmonary hepatoblastoma were reviewed. The following data were extracted from each patient: age, gender, histological subtyping, cycles of OVT, tumor size, biomarkers, chemotherapy regimen and dosage, RFA details, treatment response, follow up, and patient outcomes. The primary outcome measure was the complete response (CR) of pulmonary diseases, and secondary outcomes were event-free survival rate and overall survival rate.

RESULTS

Of 12 assessable patients, three (25%) (95% CI, 46.3-104) patients achieved PR (partial resopnse) after they finished OVT. After RFA, five (41.7%) (95% CI, 8.95-74.4) patients achieved CR (complete response). The 2 year event-free survival rate was 33% (95% CI, 20.5-64.6). The 2 year overall survival for the study group was 41.7% (95% CI, 8.9-74.4). All toxicity events were handled satisfactorily and no toxic related deaths were observed.

CONCLUSIONS

Our review report shows that OVT combined with RFA can be a successful treatment modality for previously heavily treated refractory / recurrent pulmonary metastatic lesions from hepatoblastoma.

Hepatoblastoma and Pediatric Hepatocellular Carcinoma: An Update

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

Contemporary management of hepatoblastoma

PURPOSE OF REVIEW

Hepatoblastoma is the most common primary pediatric liver malignancy. The goal of treatment in hepatoblastoma is complete surgical resection. Recently published multinational collaborative studies are better defining risk factors for disease recurrence and guide optimal treatment strategy.

RECENT FINDINGS

Successful margin-negative resection of hepatoblastoma is dependent on the location and extent of disease as defined by the PRETEXT classification. Liver transplantation is an appropriate treatment modality when complete oncological resection requires total hepatectomy. In general, advanced PRETEXT class as well as histologic features, age at presentation, tumoral production of α-feto protein and the presence of metastatic disease adversely affect outcome. Hepatoblastoma is chemosensitive and significant downstaging can occur with the use of neoadjuvant chemotherapy allowing for less extensive hepatectomy. In addition, patients at moderate-to-high risk of postresection recurrence should receive neoadjuvant chemotherapy. Cisplatin-based chemotherapy can allow for resection of transplantation of patients with metastatic disease when complete metasatectomy can be achieved albeit with inferior results.

SUMMARY

Treatment of hepatoblastoma with surgical resection or liver transplantation is associated with excellent long-term results in the setting of modern chemotherapy.

Progress toward liquid biopsies in pediatric solid tumors

Pediatric solid tumors have long been known to shed tumor cells, DNA, RNA, and proteins into the blood. Recent technological advances have allowed for improved capture and analysis of these typically scant circulating materials. Efforts are ongoing to develop "liquid biopsy" assays as minimally invasive tools to address diagnostic, prognostic, and disease monitoring needs in childhood cancer care. Applying these highly sensitive technologies to serial liquid biopsies is expected to advance understanding of tumor biology, heterogeneity, and evolution over the course of therapy, thus opening new avenues for personalized therapy. In this review, we outline the latest technologies available for liquid biopsies and describe the methods, pitfalls, and benefits of the assays that are being developed for children with extracranial solid tumors. We discuss what has been learned in several of the most common pediatric solid tumors including neuroblastoma, sarcoma, Wilms tumor, and hepatoblastoma and highlight promising future directions for the field.

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSION

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

YTHDF1 rs6090311 A>G polymorphism reduces Hepatoblastoma risk: Evidence from a seven-center case-control study

Various factors modulate the risk of hepatoblastoma. In this study, we aimed to investigate whether single nucleotide polymorphisms (SNPs) in the YTHDF1 gene could predispose to hepatoblastoma. We used TaqMan assay to genotype two YTHDF1 SNPs (rs6011668 C>T and rs6090311 A>G) in a Chinese population composed of 313 subjects with hepatoblastoma and 1446 controls from seven hospitals. We then evaluated the associations of these two SNPs with hepatoblastoma risk using unconditional logistic regression. We found that rs6090311 G allele exhibited a significant association with decreased hepatoblastoma risk [AG vs. AA: adjusted odds ratio (OR)=0.75; 95% confidence interval (CI)=0.58-0.98, P=0.033; AG/GG vs. AA: adjusted OR=0.76, 95% CI=0.59-0.97, P=0.029]. Furthermore, the combined analysis of protective genotypes revealed that subjects carrying two protective genotypes were less likely to have hepatoblastoma than those with 0-1 protective genotypes (adjusted OR=0.75, 95% CI=0.59-0.96, P=0.022). Subjects ≥17 months of age had decreased hepatoblastoma risk, in case that they carried rs6090311 AG/GG (adjusted OR=0.63, 95% CI=0.44-0.91, P=0.012), or two protective genotypes (adjusted OR=0.63, 95% CI=0.44-0.91, P=0.012). False-positive report probability analysis validated the reliability of the significant results. Preliminary functional annotations revealed that rs6090311 G was correlated with decreased expression of its surrounding genes in the expression quantitative trait locus (eQTL) analysis. In conclusion, our results indicate that the rs6090311 A>G in the YTHDF1 gene is related to decreased hepatoblastoma risk.

Insights into the Chemical Biology of Childhood Embryonal Solid Tumors by NMR-Based Metabolomics

Most childhood cancers occur as isolated cases and show very different biological behavior when compared with cancers in adults. There are some solid tumors that occur almost exclusively in children among which stand out the embryonal solid tumors. These cancers main types are neuroblastoma, nephroblastoma (Wilms tumors), retinoblastoma and hepatoblastomas and tumors of the central nervous system (CNS). Embryonal solid tumors represent a heterogeneous group of cancers supposedly derived from undifferentiated cells, with histological features that resemble tissues of origin during embryogenesis. This key observation suggests that tumorigenesis might begin during early fetal or child life due to the errors in growth or pathways differentiation. There are not many literature data on genomic, transcriptomic, epigenetic, proteomic, or metabolomic differences in these types of cancers when compared to the omics- used in adult cancer research. Still, metabolomics by nuclear magnetic resonance (NMR) in childhood embryonal solid tumors research can contribute greatly to understand better metabolic pathways alterations and biology of the embryonal solid tumors and potential to be used in clinical applications. Different types of samples, such as tissues, cells, biofluids, mostly blood plasma and serum, can be analyzed by NMR to detect and identify cancer metabolic signatures and validated biomarkers using enlarged group of samples. The literature search for biomarkers points to around 20-30 compounds that could be associated with pediatric cancer as well as metastasis.

Surgical Management of Hepatoblastoma and Recent Advances

Hepatoblastoma is the most common childhood liver malignancy. The management of hepatoblastoma requires multidisciplinary efforts. The five-year overall survival is approximately 80% in developed countries. Surgery remains the mainstay of treatment for hepatoblastoma, and meticulous techniques must be employed to ensure safe and effective local control surgeries. Additionally, there have been several advances from both pediatric and adult literature in the way liver tumor surgery is performed. In this review, we highlight important aspects of liver surgery for hepatoblastoma, the management of metastatic disease, and the most current technical advances in performing these procedures in a safe and effective manner.

The impact of cooperative group studies on childhood cancer: Improving outcomes and quality and international collaboration

The advances in pediatric cancer far exceed those achieved in adults. The success in improving survival and minimizing late effects has been due to several reasons but work of the pediatric cancer cooperative groups is a primary. These cooperative groups are multidisciplinary with medical oncologists, pathologists, radiologists, surgeons, radiation oncologists, scientists and most importantly the patients and families. Studies have expanded from regional to national and now international studies which continue to target problems pertinent to improving the outcome for children with cancer. In this article we review the history of the cooperative groups, a selection of seminal studies pertaining to solid tumors, future challenges and collaborations.

Prognostic factors for event-free survival in liver transplantation for hepatoblastoma: A single-center experience

Hepatoblastoma (HB) is the most common malignant liver tumor in children. Twenty percent of the cases may remain unresectable after neoadjuvant chemotherapy and, for these patients, liver transplant (LT) is an accepted therapeutic option. To analyze the risk factors to event-free survival (EFS) that influence the clinical outcome of patients with HB receiving LT, we retrospectively analyzed 21 patients with HB who underwent LT between January 1, 2005, and May 1, 2018. Overall survival (OS) was 90%. The univariate analysis shows that the AFP level at the time of LT was associated with a higher risk of EFS. With a ROC curve analysis, we established a cutoff point value of AFP levels at 16 000 ng/dL, with a sensitivity of 71.43% and a specificity of 85.71%. Multivariate analysis showed that patients with higher values of pretransplant AFP (>16 000 ng/dL) had a significantly higher risk of EFS than those transplanted with lower levels (HR: 10.180; 95% CI: 1.54-66.97; P = .02). Efforts should be made to improve the selection of candidates for LT for unresectable HB, aiming at a better definition of chemoresistance as a risk factor of poor outcomes.

Impact of microscopically margin-positive resection on survival in children with hepatoblastoma after hepatectomy: a retrospective cohort study

BACKGROUND

Impact of R1 (microscopically margin-positive) resection on survival of patients with hepatoblastoma (HB) remains debatable. This study aimed to compare the long-term outcomes of R0 (microscopically margin-negative) and R1 resection for HB in children after hepatectomy.

METHODS

We retrospectively reviewed files of children with HB who underwent resection at our institution between September 1, 2005, and November 30, 2017. Survival analyses and prognostic factors were evaluated using Kaplan-Meier curves and Cox regression models.

RESULTS

Of 259 patients, 218 (84.2%) underwent R0 and 41 (15.8%) R1 resection. After adjusting for confounding factors, R1 resection demonstrated non-significantly lower overall survival (OS: hazard ratio [HR] = 0.75; 95% CI 0.34-1.64) and shorter event-free survival (EFS: HR = 0.97; 95% CI 0.53-1.78) rates than R0 resection. However, stratified analysis showed significantly increased risk of poor OS and EFS in patients with metastasis and mixed epithelial/mesenchymal pathologic subtype in R1 compared with R0 resection (P values for interactions < 0.05). There was no significant difference between R0 resection with metastasis and R1 resection with metastasis in the incidence of local recurrence (P = 0.494); however, a significant difference in the incidence of local recurrence was seen between R0 and R1 resection for subgroups with mixed pathologic subtypes (P = 0.035).

CONCLUSIONS

With effective chemotherapy, microscopic margin status may not be associated with survival outcome in children with HB undergoing hepatectomy. However, stratified analysis showed that R1 resection might be associated with decreased survival in children with mixed epithelial/mesenchymal HB, compared with R0 resection, and not affect survival outcomes in those with an epithelial subtype and without metastasis.

How Do Synchronous Lung Metastases Influence the Surgical Management of Children with Hepatoblastoma? An Update and Systematic Review of the Literature

Approximately 20% of children with hepatoblastoma (HB) have metastatic disease at diagnosis, most frequently in the lungs. In children with HB, lung metastatic disease is associated with poorer prognosis. Its treatment has been approached with a variety of methods that integrate chemotherapy and surgical resection. The timing and feasibility of complete extirpation of lung metastases, by chemotherapy and/or metastasectomy, is crucial for the surgical treatment of the primary liver tumor, which can vary from major hepatic resections to liver transplantation (LT). In children with unresectable HB, which can be surgically treated only by LT, the persistence of unresectable metastases after neoadjuvant chemotherapy excludes the possibility of recurring to LT with consequent negative impact on patients' outcomes. Due to limited evidence and experience, there is no consensus amongst oncologists and surgeons across institutions regarding the surgical treatment for HB with synchronous metastatic lung disease. This narrative review aimed to update the current management of pulmonary metastasis in children with HB and to define its role in the decision-making strategy for the surgical approach to primary liver tumours.

Trial Design Challenges and Approaches for Precision Oncology in Rare Tumors: Experiences of the Children's Oncology Group

In the United States, cancer remains the leading cause of disease-related death in children. Although survival from any pediatric cancer has improved dramatically during past decades, a number of cancers continue to yield dismal prognoses, which has motivated the continued study of novel therapeutic strategies. Furthermore, even patients cured of pediatric cancer often experience severe adverse effects of treatment and other long-term health implications, such as cardiotoxicity or loss of fertility. For these patients, improved risk stratification to identify those who could safely receive alternate or less-intensive therapy without affecting prognosis is a key objective. Fortunately, pediatric cancers are rare overall, but even among patients with the same narrow cancer type, there is often broad heterogeneity in terms of prognosis, molecular features or pathology, current treatment strategies, and scientific objectives. As a result, the design of clinical trials in the pediatric cancer setting is challenged by a number of practical issues that must be addressed to ensure trial feasibility for this vulnerable group of patients. In this review, we discuss some of the unique trial design considerations often encountered in any rare tumor setting through the lens of our experiences as faculty statisticians for the Children's Oncology Group, the largest organization in the world dedicated exclusively to pediatric cancer research and clinical trials. These topics include risk stratification within individual trials, relaxation of trial operating characteristics and parameters, use of historical controls, and address of noninferiority-type objectives in small cohorts. We review each in terms of practical motivation, present challenges, and potential solutions described in the literature and implemented in selected example trials from the Children's Oncology Group.

Incidence trends and survival prediction of hepatoblastoma in children: a population-based study

Background

Hepatoblastoma is a rare disease that nevertheless accounts for the majority of liver malignancies in children. Due to limited epidemiological data, therapy for hepatoblastoma tends to be individualized. This study aimed to evaluate incidence trends of hepatoblastoma and to develop a nomogram to predict the survival of children with newly diagnosed hepatoblastoma on a population-based level.

Methods

Individuals up to 18 years of age with hepatoblastoma recorded in 18 registries of the Surveillance, Epidemiology, and End Results (SEER) database between 2004 and 2015 were examined. Joinpoint regression analyses were applied to assess incidence trends in annual percentage change (APC). Multivariable Cox regression was used to identify factors associated with overall survival (OS). A nomogram was constructed to predict OS in individual cases based on independent predictors. Concordance index (C-index) and calibration curves were used to evaluate predictive performance.

Results

Between 2004 and 2015, hepatoblastoma incidence increased significantly (APC, 2.2%; 95% confidence interval [CI] 0.5% to 3.8%, P < 0.05). In particular, this increase was observed among 2- to 4-year-old patients, males, and African–Americans. The 5- and 10-year OS rates were 81.5% and 81.0%, respectively. Age of 2 to 4 years, African–American ethnicity, and no surgery were independent predictors for short OS. Distant disease at presentation was found not to be an independent factor of survival. The nomogram had a C-index of 0.79 (95% CI 0.74–0.84) with appropriate calibration curve fitting.

Conclusions

We constructed a nomogram that integrates common factors associated with survival for hepatoblastoma patients. It provides accurate prognostic prediction for children with hepatoblastoma.

β-Catenin mutations as determinants of hepatoblastoma phenotypes in mice

Hepatoblastoma (HB) is the most common pediatric liver cancer. Although long-term survival of HB is generally favorable, it depends on clinical stage, tumor histology, and a variety of biochemical and molecular features. HB appears almost exclusively before the age of 3 years, is represented by seven histological subtypes, and is usually associated with highly heterogeneous somatic mutations in the catenin β1 (CTNNB1) gene, which encodes β-catenin, a Wnt ligand-responsive transcriptional co-factor. Numerous recurring β-catenin mutations, not previously documented in HB, have also been identified in various other pediatric and adult cancer types. Little is known about the underlying factors that determine the above HB features and behaviors or whether non-HB-associated β-catenin mutations are tumorigenic when expressed in hepatocytes. Here, we investigated the oncogenic properties of 14 different HB- and non-HB-associated β-catenin mutants encoded by Sleeping Beauty vectors following their delivery into the mouse liver by hydrodynamic tail-vein injection. We show that all β-catenin mutations, as well as WT β-catenin, are tumorigenic when co-expressed with a mutant form of yes-associated protein (YAP). However, tumor growth rates, histologies, nuclear-to-cytoplasmic partitioning, and metabolic and transcriptional landscapes were strongly influenced by the identities of the β-catenin mutations. These findings provide a context for understanding at the molecular level the notable biological diversity of HB.

Survival and analysis of prognostic factors for hepatoblastoma: based on SEER database

Background

The goal of this study is to assess the newest survival of hepatoblastoma (HB) and the risk factors which impacted on survival by using the Surveillance, Epidemiology and End Results (SEER) database, also calculate the incidence of HB in recent years.

Methods

We calculate age-adjusted incidence of HB by using SEER 21 registries. Age, sex, race, tumor size, macrovascular involvement, multifocal tumor, distant metastasis, the way of treatment, and the survival were collected for survival and analysis of prognostic factors in SEER 18 registries. Survival curves, according to different factors, were obtained by Kaplan-Meier estimates. Multivariable Cox regression models were also built.

Results

The overall age-adjusted incidence of HB was 0.19 patients per 100,000 children with a statistically significant increase per year. Overall survival (OS) at 1-, 3- and 5-year for all patients were 89.3%, 84.6%, and 81.9%, respectively. Multivariate analysis showed tumor size >5 cm [hazard ratio (HR), 8.271; 95% confidence interval (CI), 1.134-60.310], multiple tumors (HR, 2.578; 95% CI, 1.424-4.668) and no-surgery treatment (HR, 7.520; 95% CI, 4.121-13.724) were independent indicators of poor prognosis. Only the age ≥2-year-old (HR, 3.240; 95% CI, 1.433-7.326) and multiple tumors (HR, 2.395; 95% CI, 1.057-5.430) were the risk factors for the surgical treatment group.

Conclusions

The survival of patients with HB has been greatly improved in the recent years, and at the same time, due to the application of better chemotherapy, we should re-evaluate the traditional risk indicators of prognosis in order to better apply to the clinical.

Prognostic Factors for Event-Free Survival in Pediatric Patients with Hepatoblastoma Based on the 2017 PRETEXT and CHIC-HS Systems

This study aimed to evaluate the prognostic value of variables used in the 2017 PRE-Treatment EXTent of tumor (PRETEXT) system and the Children's Hepatic tumors International Collaboration-Hepatoblastoma Stratification (CHIC-HS) system in pediatric patients with hepatoblastoma. A retrospective analysis of data from the pediatric hepatoblastoma registry of a tertiary referral center was conducted to evaluate the clinical and imaging variables (annotation factors) of the PRETEXT staging system. The primary outcome was event-free survival (EFS). Data from 84 patients (mean age: 2.9 ± 3.5 years) identified between 1998 and 2017 were included. Univariable Cox proportional hazards analysis revealed that PRETEXT annotation factors P (portal vein involvement), F (multifocality of tumor), and M (distant metastasis) showed a significant negative association with EFS. Multivariable Cox proportional hazard analysis showed that factor F was the strongest predictor (HR (hazard ratio), 2.908; 95% CI (confidence interval), 1.061-7.972; p = 0.038), whereas factor M showed borderline significance (HR, 2.416; 95% CI, 0.918-6.354; p = 0.074). The prediction model based on F and M (F + M) showed good performance to predict EFS (C-statistic, 0.734; 95% CI, 0.612-0.854). In conclusion, the PRETEXT annotation factor F was the strongest predictor of EFS, and the F + M model showed good performance to predict EFS in pediatric patients with hepatoblastoma.

Neurokinin-1 Receptor Antagonists against Hepatoblastoma

Hepatoblastoma (HB) is the most common malignant liver tumor that occurs during childhood. The prognosis of children with HB is favorable when a complete surgical resection of the tumor is possible, but for high-risk patients, the prognosis is much worse. New anti-HB strategies must be urgently developed. The undecapeptide substance P (SP) after binding to the neurokinin-1 receptor (NK-1R), regulates cancer cell proliferation, exerts an antiapoptotic effect, induces cell migration for invasion/metastasis, and triggers endothelial cell proliferation for neoangiogenesis. HB samples and cell lines overexpress NK-1R (the truncated form) and SP elicits HB cell proliferation. One of these strategies could be the use of non-peptide NK-1R antagonists. These antagonists exert, in a concentration-dependent manner, an antiproliferative action against HB cells (inhibit cell proliferation and induce the death of HB cells by apoptosis). NK-1R antagonists exerted a dual effect in HB: Decreased both tumor volume and angiogenic activity. Thus, the SP/NK-1R system is an important target in the HB treatment and NK-1R antagonists could act as specific drugs against HB cells. In this review, we update and discuss the use of NK-1R antagonists in the treatment of HB.