Relapses in hepatoblastoma patients: Clinical characteristics and outcome – Experience of the International Childhood Liver Tumour Strategy Group (SIOPEL)

Successful Treatment of Refractory or Relapsed Hepatoblastoma With Autologous Hematopoietic Stem Cell Transplantation in Children

BACKGROUND

The standard-risk hepatoblastoma has a good prognosis in children; however, refractory or relapsed (R/R) hepatoblastoma has a poor prognosis and high mortality rate. This study aimed to demonstrate the efficacy of high-dose chemotherapy and autologous hematopoietic stem cell transplantation (HSCT) rescue in pediatric patients with R/R hepatoblastoma.

METHODS

We retrospectively analyzed 6 pediatric patients with R/R hepatoblastoma who underwent autologous HSCT. The MEC conditioning regimen was used for all patients, comprising melphalan 140 mg/m2/day intravenously (IV) on day 7 and 70 mg/m2 on day 6, etoposide 200 mg/m2 IV on days 5 to 8, and carboplatin 400 mg/m2 IV on days 5 to 8. One patient received a TopoThioCarbo regimen, comprising topotecan 2 mg/m2/day IV on days 4 to 8, thiotepa 300 mg/m2/day IV on days 6 to 8, and carboplatin 500 mg/m2/day IV on days 3 to 5, as the conditioning regimen for the first transplantation. This was followed by salvage chemotherapy for relapse, and the second transplantation was performed using MEC as the conditioning regimen.

RESULTS

We report the retrospective results of 6 patients with a median age of 1.8 (range 0.4 to 10.2) years who had R/R hepatoblastoma and underwent autologous HSCT. The median follow-up period was 58 (range 28 to 113) months after diagnosis. The median stage at diagnosis was 2.0 (range 2 to 4). Two patients had lung metastases during diagnosis. The median initial alpha-fetoprotein level was 292,888 (range 28,831 to 2,406,942) ng/mL, and the median number of chemotherapy lines before autologous HSCT was 3.5 (range 2 to 7). The disease status before HSCT was complete remission (CR) for all patients. The engraftment rate was 100%. No treatment-related mortality was reported. The 3-year event-free survival and overall survival rates were 83.3% and 100%, respectively. One patient relapsed after the second HSCT and achieved CR after salvage chemotherapy.

CONCLUSION

This study suggests autologous HSCT as an effective treatment in pediatric patients with R/R hepatoblastoma. Nevertheless, future large-scale prospective studies are warranted.

The Utility of Serum Alpha-fetoprotein for Monitoring for Relapse of Alpha-fetoprotein-Positive Hepatoblastoma

Hepatoblastoma is the most common liver malignancy in children. Treatment typically involves surgery and cisplatin-based chemotherapy. After therapy completion, children undergo repetitive surveillance imaging to screen for relapse, which occurs in <12% of cases. Monitoring for relapse has gradually shifted to serial determination of serum alpha-fetoprotein (AFP) alone as most cases have AFP elevation at the time of relapse. Little primary data supports, such a practice, however, and herein we present both our institutional experience with relapsed hepatoblastoma and a careful review of published literature on this topic. While serial AFP monitoring may suffice for most patients, certain clinical characteristics should give pause to the practitioner, when considering posttreatment monitoring with serum AFP alone.

The RELIVE consortium for relapsed or refractory pediatric hepatoblastoma and hepatocellular carcinoma: a scoping review of the problem and a proposed solution

Liver tumors account for approximately 2% of all pediatric malignancies. Children with advanced stages of hepatoblastoma (HB) are cured only 50-70% of the time while children with advanced hepatocellular carcinoma (HCC) have a <20% 5-year overall survival. This scoping review was performed to highlight the paucity of rigorous, reliable data guiding the management of relapsed pediatric HB or HCC. When these patients are enrolled on prospective trials, the trials are often histology-agnostic, exclude patients less than a year of age, lack a liquid formulary of the drug under study, exclude recipients of a solid organ transplant, and enroll only 1-2 patients limiting the ability to deduce efficacious regimens for current use or future study. We highlight the creation of a global pediatric consortium intended to source retrospective relapse data from over 100 institutions spanning 4 continents. The data collected from this effort will inform future relapse trials.

Hepatoblastoma Relapse-Findings from the German HB99 Trial and the German Liver Tumor Registry

Survival rates for HB patients have improved; however, outcomes for patients who relapse remain poor. A retrospective review of information gathered for the HB99 study and the German Liver Tumor Registry identified 25 relapse patients (6.9%, 25/362). The median time from initial diagnosis to first relapse was 13 months (range: 5-66 months). Two patients relapsed >36 months after initial diagnosis. A total of 68% (17/25) of relapses were metastatic, 24% local, and 8% combined. 67% of local relapses were alive at the last follow-up, in contrast to 53% of metastatic and 0% of combined relapses. At the last follow-up, 73% (8/11) of patients with lung relapses were still alive (0/4 with peritoneal, 1/2 with CNS involvement). A total of 20% of the patients had AFP-negative relapses, 64% of the relapse patients achieved a second complete remission, 69% were still in complete second remission at the last follow-up (median FU of 66 months), and 83% (5/6) of irinotecan-naïve patients who received relapse treatment including irinotecan were in second complete remission at the last follow-up. The 3-year overall survival/event-free survival from relapse was 63%/48% respectively. There is a good chance that HB patients will achieve a second remission despite a first relapse. However, patients who suffer further relapses tend to have a poorer prognosis.

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.

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.

BEX1 supports the stemness of hepatoblastoma by facilitating Warburg effect in a PPARγ/PDK1 dependent manner

BACKGROUND

Hepatoblastoma (HB) is a highly aggressive paediatric malignancy that exhibits a high presence of cancer stem cells (CSCs), which related to tumour recurrence and chemotherapy resistance. Brain expressed X-linked protein 1 (BEX1) plays a pivotal role in ciliogenesis, axon regeneration and differentiation of neural stem cells. However, the role of BEX1 in metabolic and stemness programs in HB remains unclear.

METHODS

BEX1 expression in human and mouse HB was analyzed using gene expression profile data from NCBI GEO and immunohistochemical validation. Seahorse extracellular flux analyzer, ultra-high-performance liquid-chromatography mass spectrometry (LC-MS), flow cytometry, qRT-PCR, Western Blot, sphere formation assay, and diluted xenograft tumour formation assay were used to analyze metabolic and stemness features.

RESULTS

Our results indicated that overexpression of BEX1 significantly enhanced the Warburg effect in HB cells. Furthermore, glycolysis inhibition largely attenuated the effects of BEX1 on HB cell growth and self-renewal, suggesting that BEX1 promotes stemness maintenance of HB cells by regulating the Warburg effect. Mechanistically, BEX1 enhances Warburg effect through the downregulation of peroxisome proliferator-activated receptor-gamma (PPARγ). Furthermore, pyruvate dehydrogenase kinase isozyme 1 (PDK1) is required for PPARγ-induced inhibition of Warburg effect in HB. In addition, BEX1 supports the stemness of HB by enhancing Warburg effect in a PPARγ/PDK1 dependent manner.

CONCLUSIONS

HB patients with high BEX1 and PDK1 expression had a poor prognosis. BEX1 promotes the stemness maintenance of HB cells via modulating the Warburg effect, which depends on PPARγ/PDK1 axis. Pioglitazone could be used to target BEX1-mediated stemness properties in HB by upregulating PPARγ.

Surgical Management and Outcomes of Patients with Multifocal Hepatoblastoma

OBJECTIVE

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

LEVEL OF EVIDENCE

III.

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

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

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.

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.

Surgical management in hepatoblastoma: points to take

Hepatoblastoma is the most common primary malignant paediatric liver tumour and surgery remains the cornerstone of its management. The aim of this article is to present the principles of surgical treatment of hepatoblastoma. All aspects of surgery in hepatoblastoma are discussed, from biopsy, through conventional and laparoscopic liver resections, to extreme resection with adjacent structures, staged hepatectomy and transplantation.

A population-based assessment of metastatic hepatoblastoma in Texas reveals ethnic disparities

Background

Hepatoblastoma (HB) is the most common primary liver cancer in children with emerging evidence that incidence is increasing globally. While overall survival for low risk hepatoblastoma is >90%, children with metastatic disease have worse survival. As identifying factors associated with high-risk disease is critical for improving outcomes for these children, a need for a further understanding of the epidemiology of hepatoblastoma is warranted. Therefore, we conducted a population-based epidemiologic study of hepatoblastoma in Texas, a large state characterized by ethnic and geographic diversity.

Methods

Information on children diagnosed with hepatoblastoma at 0-19 years of age for the period of 1995-2018 was obtained from the Texas Cancer Registry (TCR). Demographic and clinical variables including sex, race/ethnicity, age at diagnosis, urban-rural status, and residence along the Texas-Mexico border were evaluated. Multivariable Poisson regression was used to calculate adjusted incidence rate ratios (aIRRs) and 95% confidence intervals (CIs) for each variable of interest. Joinpoint regression analysis was used to determine the trend in incidence of hepatoblastoma, overall and by ethnicity.

Results

Overall, 309 children diagnosed with hepatoblastoma in Texas for the period of 1995-2018. Joinpoint regression analysis showed no joinpoints in the overall or the ethnic-specific analyses. Over this period, the incidence increased at 4.59% annually; with the annual percent change higher among Latinos (5.12%) compared to non-Latinos (3.15%). Among these children, 57 (18%) had metastatic disease at diagnosis. Factors associated with hepatoblastoma included male sex (aIRR = 1.5, 95% CI: 1.2-1.8, p = 0.002); infancy (aIRR = 7.6, 95% CI: 6.0-9.7, p < 0.001); and Latino ethnicity (aIRR = 1.3, 95% CI: 1.0-1.7, p = 0.04). Additionally, children living in rural areas were less likely to develop hepatoblastoma (aIRR = 0.6, 95% CI: 0.4-1.0, p = 0.03). While residence on the Texas-Mexico border association with hepatoblastoma approached statistical significance (p = 0.06) in unadjusted models, this finding did not remain significant after adjusting for Latino ethnicity. The two factors associated with being diagnosed with metastatic hepatoblastoma included Latino ethnicity (aIRR = 2.1, 95% CI: 1.1-3.8, p = 0.02) and male sex (aIRR = 2.4, 95% CI: 1.3-4.3, p = 0.003).

Conclusions

In this large population-based study of hepatoblastoma, we found several factors associated with hepatoblastoma and metastatic disease. The reasons for a higher burden of hepatoblastoma among Latino children is unclear but could be due to differences in geographic genetic ancestry, environmental exposures, or other unmeasured factors. Additionally, it is notable that Latino children were also more likely to be diagnosed with metastatic hepatoblastoma compared to non-Latino white children. To our knowledge, this has not been previously reported and warrants further study to delineate the causes of this disparity and identify interventions to improve outcomes.

Role of Diffusion Weighted MRI (DW-MR) in Detection of Satellite Lesions Not Detected with Multiphase CT Scans in Hepatoblastoma and Its Implications for Management

OBJECTIVE

To evaluate the role of diffusion-weighted magnetic resonance imaging (DW-MR) in hepatoblastoma as compared to multiphase contrast enhanced computed tomography (CECT) scans for detection of satellite lesions.

METHODS

In this prospective study on new cases of hepatoblastoma, multiphase CECT scans and DW-MR were performed before initiation of chemotherapy. Results of interpretation were compared for detection of satellite lesions. PRETEXT grouping and risk categorization was done according to SIOPEL based on CECT scan.

RESULTS

Nine boys and 1 girl with hepatoblastoma, with median age of 11.5 mo were included. All patients were stratified as high-risk group with 2 (20%) in PRETEXT II and 8 (80%) in PRETEXT III. In 2 of 10 (20%) patients, additional satellite lesions were detected on DW-MR, which upgraded their stage. One of the two patients had one satellite lesion identified on CECT, while additional seven satellite lesions were identified on DW-MR imaging. For the other patient, CECT showed no satellite lesion while DW-MR detected six satellite lesions.

CONCLUSION

MRI has become the gold standard investigation for evaluation of hepatoblastoma. DW-MR, which is a contrast free technique, is a better tool for assessment of satellite lesions which are usually missed on CECT. This would help in proper staging, planning of management and prognostication.

Repeat hepatectomy for pediatric recurrent chemotherapy-resistant hepatoblastoma: a report of 18 cases

BACKGROUND AND AIMS

Repeat hepatectomy for adult recurrent hepatocellular carcinoma significantly prolongs the overall survival, but repeat hepatectomy for pediatric recurrent hepatoblastoma (HB) is rarely reported, and the outcomes are warranted to be investigated.

METHODS

All patients between May 2015 and December 2020 with recurrent HB after intended surgical cure were retrospectively evaluated. Clinicopathologic features, surgical details and outcomes were analyzed during a median following-up of 24 months after repeat hepatectomy. Survival analysis was performed using the Kaplan-Meier estimate.

RESULTS

A total of 18 patients of recurrent HB undergoing repeat hepatectomy with radical cure intention were included. There were 11 males and 7 females. The median age was 29 months (range 5-87 months) at first hepatectomy, and the median time to the recurrence from the first hepatectomy was 7 months. The operating time of the repeat hepatectomy was 5.0 h (range 3.5-9.0 h) and the mean blood loss was 592 ml (range 50-3200 ml). Radical resection (R0) was achieved in 12 patients (66.7%), with a postoperative hospital stay of 7.9 ± 1.8 days. No serious postoperative complications or mortality occurred. The overall survival (OS) rate was 55.6% (10/18) and the event-free survival (EFS) rate was 33.3% (6/18). Those with no lung metastases, not high-risk stratification, and achieving R0 hepatectomy, anatomic hepatectomy had longer OS rate (all P < 0.05) after repeat hepatectomy. Two of three patients with re-recurrence HB undergoing salvage liver transplantation were alive with a tumor-free survival.

CONCLUSIONS

Repeat hepatectomy for recurrent HB can be carried out safely. However, only a highly selected subgroup of patients might actually benefit from this procedure.

Treatment optimization for recurrent hepatoblastoma: retrospective study from a hepatoblastoma cohort in Southern China

PURPOSE

The present study aimed to explore the clinical characteristics and optimal treatments of RHB patients.

METHODS

We retrospectively collected 42 RHB cases and 161 primary HB (PHB) cases. Clinical characteristics were compared between RHB and PHB patients. The risk factors related to overall survival (OS) and progression-free survival (PFS) in RHB patients were explored by COX regression analysis. Patients were further divided into curable and refractory subgroup by treatments. Propensity score match (PSM) analysis was performed to match recurrent curable patients from 145 curable PHB patients from the same cohort. PFS was further compared between 34 pairs of primary and recurrent curative HB patients.

RESULTS

Recurrence treatment and number of relapsed tumors were significantly related with both OS and PFS of RHB patients (p < 0.05). Chemotherapy regimen alteration was also risk factor of PFS for RHB (HR = 4.26; 95% CI = 1.54-11.78; p = 0.005). RHB patients underwent curable treatment had better prognosis, compared with recurrent refractory subgroup (p < 0.001). Matched curable PHB patients demonstrated no significant difference of 3-year PFS with curable RHB patients (p = 0.540).

CONCLUSION

Curable RHB patients might get benefit from surgery or ablation with similar prognosis with primary curable HB patients.

Salvage Liver Transplant in the Treatment of a Child With Local Recurrence of Hepatoblastoma

Hepatoblastoma is the most common primary liver cancer of childhood, accounting for two-thirds of primary malignant hepatic neoplasms. Radical surgical removal combined with efficient chemotherapy is essential for cure. Despite a complete tumor resection, hepatoblastoma may recur as isolated local disease. Intrahepatic recurrence of hepatoblastoma after liver resection is among the indications for liver transplant. Here, we present a patient who underwent salvage liver transplant for the treatment of local recurrence of hepatoblastoma. A 13-year-old boy who was diagnosed with hepatocellular carcinoma arising from the left liver lobe and who had been treated with surgical resection was admitted to our outpatient oncology clinic for further evaluation because alpha-fetoprotein levels had started to increase after surgery. Histopathological reexamination of hemihepatectomy material showed a histological aspect of an epithelial hepatoblastoma. Magnetic resonance imaging revealed multifocal lesions in the right liver lobe compatible with local recurrence. Despite a favorable initial response to chemotherapy, the tumor showed progression with increased alpha-fetoprotein levels. The patient was deemed a viable candidate for an urgent liver transplant and underwent right lobe living donor liver transplant. He had excellent graft function without any complications or signs of malignancy in the last follow-up visit at 7 months posttransplant. Salvage liver transplant is a lifesaving and sometimes the only treatment option for patients with local recurrence of hepatoblastoma. Although transplant in the salvage setting has been associated with worse outcomes than primary transplant, recent data have indicated more favorable and acceptable outcomes. Further studies are warranted to better understand the role of salvage liver transplant in the treatment of hepatoblastoma. Early consultation with the liver transplant team is critical in children who are most likely to need extreme resection or liver transplant.

Current Approaches in Hepatoblastoma-New Biological Insights to Inform Therapy

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

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

Objective

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

Methods

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

Results

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

Conclusion

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

Surgical Resection of Hepatoblastoma: Factors Affecting Local Recurrence

INTRODUCTION

 This study aimed to investigate potential factors contributing to local recurrence after surgical resection of hepatoblastoma (HB).

MATERIALS AND METHODS

 This retrospective study involving all patients with HB who underwent nontransplant surgery at our tertiary center between July 2007 and July 2018. Data were analyzed regarding microscopic surgical resection margin, tumor multifocality and extracapsular tumor extension in correlation with local recurrence. These relations were assessed by logistic regression.

RESULTS

 The study included 133 patients with a median age of 1.3 years (range: 0.5-12.8 years). They were classified into 99 cases (74.44%) standard risk and 34 cases (25.56%) high risk. Delayed surgical resection was adopted in all patients. Follow-up to July 2019 revealed that 23 patients (23/133, 17.3%) developed local recurrence, whereas the remaining 110 were locally disease free. Microscopic positive margin (R1) was detected in 29 patients, 8 of them had local recurrence (p = 0.097). Regarding tumor multifocality, there were 12 patients who had multifocal lesions, 3 of them developed local recurrence (p = 0.459). Forty-four patients had extracapsular tumor extension in their pathological reports, 12 of them had local recurrence (p = 0.032).

CONCLUSION

 Extracapsular tumor extension was a significant prognostic factor of local recurrence after surgical resection of HB. R1 margin does not necessarily require a second resection, and it could achieve accepted results when combined with adjuvant platinum-based chemotherapy. However, patients who are not eligible for surgical resection must be transferred for primary transplantation to obtain favorable outcome.

Outcomes of Central Hepatectomy for Pediatric Liver Tumors

BACKGROUND

Central hepatectomy (CH) is an uncommon surgical technique that is an option for resection of centrally located tumors, with the advantage of sparing normal hepatic parenchyma. Few studies have described outcomes in children undergoing CH.

MATERIALS AND METHODS

An IRB-approved, retrospective chart review of patients who underwent CH at Children's Hospital Los Angeles between 2005 and 2016 was performed. Data included patient demographics, peri-operative factors, and post-operative outcomes. The IRB approved waiver of consent.

RESULTS

Eight patients (4F:4M) with median age of 1.9 Y underwent CH: 7 patients for HB and 1 patient for focal nodular hyperplasia. Two of the seven HB patients had metastatic disease at diagnosis. Six of the seven HB patients received a median of 4 rounds (3-7 rounds) of pre-operative chemotherapy. The median operative time was 197.5 Min (143-394 Min) with median blood loss of 175 mL (100-1200 mL). Complications included a bile fluid collection requiring aspiration. Seven patients had negative margins on pathology. One patient with a positive margin successfully completed therapy, without recurrent disease. All patients survived to follow-up, with a median follow-up duration of 1.1 Y (0.1-12.1 Y). Two patients developed recurrent disease requiring formal hepatic lobectomy and orthotopic liver transplantation. These patients had negative pathologic margins, with tumor within 1 mm of resection margins.

CONCLUSION

CH is an effective alternative to extended hepatectomy for patients with centrally located liver tumors and is associated with good clinical and pathologic outcomes.

A Comprehensive Genomic Analysis Constructs miRNA-mRNA Interaction Network in Hepatoblastoma

Hepatoblastoma (HB) is a rare disease but nevertheless the most common hepatic tumor in the pediatric population. For patients with advanced HB, the prognosis is dismal and there are limited therapeutic options. Multiple microRNAs (miRNAs) were reported to be involved in HB development, but the miRNA–mRNA interaction network in HB remains elusive. Through a comparison between HB and normal liver samples in the GSE131329 dataset, we detected 580 upregulated differentially expressed mRNAs (DE-mRNAs) and 790 downregulated DE-mRNAs. As for the GSE153089 dataset, the first cluster of differentially expressed miRNAs (DE-miRNAs) were detected between fetal-type tumor and normal liver groups, while the second cluster of DE-miRNAs were detected between embryonal-type tumor and normal liver groups. Through the intersection of these two clusters of DE-miRNAs, 33 upregulated hub miRNAs, and 12 downregulated hub miRNAs were obtained. Based on the respective hub miRNAs, the upstream transcription factors (TFs) were detected via TransmiR v2.0, while the downstream target genes were predicted via miRNet database. The intersection of target genes of respective hub miRNAs and corresponding DE-mRNAs contributed to 250 downregulated candidate genes and 202 upregulated candidate genes. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses demonstrated the upregulated candidate genes mainly enriched in the terms and pathways relating to the cell cycle. We constructed protein–protein interaction (PPI) network, and obtained 211 node pairs for the downregulated candidate genes and 157 node pairs for the upregulated candidate genes. Cytoscape software was applied for visualizing the PPI network and respective top 10 hub genes were identified using CytoHubba. The expression values of hub genes in the PPI network were subsequently validated through Oncopression database followed by quantitative real-time polymerase chain reaction (qRT-PCR) in HB and matched normal liver tissues, resulting in six significant downregulated genes and seven significant upregulated genes. The miRNA–mRNA interaction network was finally constructed. In conclusion, we uncover various miRNAs, TFs, and hub genes as potential regulators in HB pathogenesis. Additionally, the miRNA–mRNA interaction network, PPI modules, and pathways may provide potential biomarkers for future HB theranostics.

Percutaneous thermal ablation versus open liver resection for recurrent hepatoblastoma: a retrospective study

BACKGROUND

The survival of children with recurrent hepatoblastoma (RHB) is still unsatisfactory and the treatment for relapsed patients is challenging.

PURPOSE

To compare short-term results between open liver resection (OLR) and percutaneous thermal ablation (TA) in the treatment of RHB and provide evidence to support the treatment options for such patients.

METHODS

A retrospective data of 21 patients with RHB in two Chinese centers were analyzed from January 2013 to May 2019. The baseline indicators and clinical effect of the two groups of children were compared.

RESULTS

There was no statistical difference in baseline indicators between the two groups of children, and complete remission (CR) was achieved after comprehensive treatment. The median follow-up time was 30 months (IQR 38.5 months) in the TA group, and 23 months (IQR 21.7 months) in OLR group (p = .57). The 2-year OS rates were 92.3% in the percutaneous TA group and 87.5% in the OLR group (p = .68, HR = 1.6, 95% confidence interval [CI]: 0.2-12.4). The 2-year EFS rates were 66.7%, in the TA group and 50.0% in the OLR group (p = .51, HR = 0.6, 95% CI: 0.2-2.6). Compared with the OLR group, TA group had shorter operation time (3.5 ± 1.8 vs. 0.5 ± 0.1, p < .001) and postoperative hospitalization time (11.8 ± 3.0 vs. 9.5 ± 6.8 d, p = .045). No major complications occurred in both groups.

CONCLUSIONS

Ultrasound-guided percutaneous TA for RHB is a safe and effect treatment option for children. It has comparable effect with surgery within 2 years after treatment. Particularly, due to its minimally invasive advantage, it needs shorter operation and hospitalization time. Percutaneous ablation may be an alternative minimally invasive treatment for RHB children.

Liver Tumors in Pediatric Patients

The most recent advance in the care of children diagnosed with hepatoblastoma and hepatocellular carcinoma is the Pediatric Hepatic International Tumor Trial, which opened to international enrollment in 2018. It is being conducted as a collaborative effort by the pediatric multicenter trial groups in North America, Europe, and the Far East. This international effort was catalyzed by a new unified global risk stratification system for hepatoblastoma, an international histopathologic consensus classification for pediatric liver tumors, and a revised 2017 collaborative update of the PRE-Treatment EXTent of disease radiographic based staging system.

Identification of potential key genes and miRNAs involved in Hepatoblastoma pathogenesis and prognosis

Hepatoblastoma (HB) is one of the most common liver malignancies in children, while the molecular basis of the disease is largely unknown. Therefore, this study aims to explore the key genes and molecular mechanisms of the pathogenesis of HB using a bioinformatics approach. The gene expression dataset GSE131329 was used to find differentially expressed genes (DEGs). Functional and enrichment analyses of the DEGs were performed by the EnrichR. Then, the protein-protein interaction (PPI) network of the up-regulated genes was constructed and visualized using STRING database and Cytoscape software, respectively. MCODE was used to detect the significant modules of the PPI network, and cytoHubba was utilized to rank the important nodes (genes) of the PPI modules. Overall, six ranking methods were employed and the results were validated by the Oncopression database. Moreover, the upstream regulatory network and the miRNA-target interactions of the up-regulated DEGs were analyzed by the X2K web and the miRTarBase respectively. A total of 594 DEGs, including 221 up- and 373 down-regulated genes, were obtained, which were enriched in different cellular and metabolic processes, human diseases, and cancer. Furthermore, 15 hub genes were screened, out of which, 11 were validated. Top 10 transcription factors, kinases, and miRNAs were also determined. To the best of our knowledge, the association of RACGAP1, MKI67, FOXM1, SIN3A, miR-193b, and miR-760 with HB was reported for the first time. Our findings may be used to shed light on the underlying mechanisms of HB and provide new insights for better prognosis and therapeutic strategies.

Exploration of CTNNB1 ctDNA as a putative biomarker for hepatoblastoma

Driver mutations in the CTNNB1 gene (encoding β-catenin) are a hallmark of sporadic hepatoblastoma (HBL). Our results show that CTNNB1 circulating tumour DNA (ctDNA) is readily detected in patients diagnosed with localised HBL, with serial sampling along the course of therapy and follow up providing a sensitive mechanism to monitor tumour dynamics and response to treatment. This exciting potential for CTNNB1 ctDNA to serve as a biomarker for treatment response in HBL holds clinical value, and requires assessment in a larger cohort of mixed tumour stages and recurrent disease.

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.

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.

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.

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.

Hepatoblastoma relapses with a normal level of alpha-fetoprotein: report of two cases

Hepatoblastoma (HB) is the most common malignant liver tumor in children. The level of alpha-fetoprotein (AFP) is used for monitoring the response to antitumor therapy and for diagnosing relapses. The occurrence of HB relapses with normal AFP levels in patients who had elevated levels of this tumor marker at disease onset is considered to be an uncommon situation. The aim of this study was to describe cases in which AFP-negative hepatoblastoma relapses developed. The study participants included two HB patients who were initially stratified into high-risk and standard-risk groups and who received treatment at the Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology and the Petrovsky National Research Center of Surgery inMoscow. At the moment of relapse acknowledgement these patients had normal AFP levels, which was confirmed by serial measurements. Immunohistochemistry (IHC) tests were performed on paired samples of the tumor at disease onset and at disease relapse respectively to evaluate AFP expression. The presented clinical cases demonstrate that normal AFP levels, when accompanied by suspicious clinical symptoms, do not allow to exclude an HB relapse. The possibility of relapse with a normal AFP level reinforces the importance of following the current plan of screening tests, which includes not only an evaluation of AFP levels, but also other tests such as a chest X-ray and an abdominal ultrasound. Parents gave their consent to use information about the child in the article.

Analysis of factors related to recurrence of paediatric hepatoblastoma - a single Centre retrospective study

Background

This study was performed to identify risk factors associated with recurrence of hepatoblastoma.

Methods

A retrospective study was conducted on 56 patients with hepatoblastoma from 2012 to 2015 in Beijing Children’s Hospital. Pretreatment extension stage (PRETEXT), serum alpha fetoprotein (AFP) value, change trend of tumors after treatment and some other clinical characteristics were collected and analyzed. The comparison of independent variables that were not distributed normally was performed with the log-rank test.

Results

Twenty-eight patients with tumour recurrence and 28 patients without recurrence were included in this study, and the median age at presentation was 46.5 (26, 71.5) months. There was a significant difference in the 3-year recurrence-free survival (RFS) probability between patients aged over 54 months and those younger than 54 months (p = 0.007). After neoadjuvant chemotherapy, the chance of recurrence in partial response (PR) patients was significantly lower than that in stable disease (SD) patients (p = 0.004). The 3-year RFS rate of patients with a reduction in AFP of more than 60% after neoadjuvant chemotherapy was significantly higher than that of patients with a reduction of less than 60% (p = 0.005). The postoperative follow-up revealed that patients whose postoperative AFP fell to normal levels within 6 months of the start of treatment had a 3-year RFS rate of 68.6%, which is higher than that of patients whose AFP fell below the normal range after 6 months (p = 0.0005). Finally, the multivariate analysis by Cox regression showed that AFP decreased by less than 60% and tumour size decreased by less than 50% after neoadjuvant chemotherapy were significant independent prognostic risk factors for the 3-year RFS rate. The other clinical features were not significantly associated with tumour recurrence in this study.

Conclusions

Through this study, we concluded that the prognosis of childhood HB is related to the age at presentation and the response of chemotherapy. The results of the multivariate analysis showed that AFP decreased by less than 60% and tumour size decreased by less than 50% after neoadjuvant chemotherapy were significant independent prognostic risk factors. These findings can be helpful to evaluate therapeutic effects and predict prognosis.

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.

Surgical management of locally-advanced and metastatic hepatoblastoma

Advanced stage hepatoblastoma, including both locally advanced primary tumors as well as metastatic disease, poses unique clinical challenges. Despite substantial advances in chemotherapeutics, surgical extirpation remains the mainstay of cure for this tumor. Locally advanced tumors that involve multiple hepatic lobes and/or invade significant vascular structures can be managed either by complex hepatic resections or liver transplantation. We review the indications, roles, and outcomes of these surgical approaches as well as those for the resection of pulmonary metastases.

Microwave ablation assisted by three-dimensional visualization system as local therapy for relapsed hepatoblastoma: a small pilot study

PURPOSE

We aimed to explore the feasibility of microwave ablation (MWA) assisted by three-dimensional visualization system for relapsed HB in children.

METHODS

From August 2014 to February 2017, five patients with relapsed HB were enrolled. A total of 12 liver tumors were treated with MWA assisted by a three-dimensional visualization system. Follow-up data were obtained in all patients. The residual liver volume, local tumor progression, new intrahepatic tumors, survival outcome, and complications were analyzed.

RESULTS

All tumors were completely ablated in a single session. The mean ablation time per tumor was 9.7 ± 8.6 min, and the median ablation/liver volume ratio was 2.37%. No local tumor progression was observed during a follow-up period of 9-39 months. All patients were still alive at the end of the follow-up. The median progression-free survival time after ablation was 9 months, and the median survival time after ablation was 12 months. No other complications were observed except for fever.

CONCLUSIONS

MWA assisted by three-dimensional visualization system appears to be a safe and feasible local treatment for recurrent HB in pediatric patients.

Multifocal hepatoblastoma: What is the risk of recurrent disease in the remnant liver?

PURPOSE

Multifocal hepatoblastoma (HB) is often treated with total hepatectomy and transplantation owing to concerns of surgical resectability, local recurrence, and/or metachronous tumor in the remnant liver. We aimed to review HB patients to determine the risk of local recurrence in multifocal disease.

METHODS

We undertook retrospective cohort analysis of all HB patients at a single tertiary referral center between 2001 and 2015. Demographics, diagnostic features, operative details, and outcomes were analyzed.

RESULTS

Sixty patients underwent surgical management of HB. 39 had unifocal, and 21 had multifocal disease. Of multifocal patients, 9 underwent liver transplantation, 10 anatomic resections, and 2 nonanatomic resections. Overall, two patients had recurrence in the remnant liver - both from the unifocal group. There were equivalent distant (lung) recurrences between the groups (8% for unifocal versus 14% for multifocal), p = 0.89. At a mean of 75 months of follow-up, overall survival was 97% for unifocal patients and 86% for multifocal patients, p = 0.12.

CONCLUSION

Multifocal HB was not associated with increased local recurrence in the setting of R0 resection and chemotherapy. These data do not support the contention that all patients with multifocal HB require a total hepatectomy and transplantation to reduce the incidence of local recurrence and/or metachronous tumor development.

LEVEL OF EVIDENCE

Level III - Limited cohort analysis.

Phase I clinical study of oral olaparib in pediatric patients with refractory solid tumors: study protocol

Background

There is no established standard chemotherapy for recurrent pediatric solid tumors such as neuroblastoma and sarcoma. Since some of these tumor cells show dysfunctions in homologous recombination repair, the goal is to conduct a phase I study of olaparib, a poly(ADP-ribose) polymerase inhibitor. In this clinical trial, the aims are to evaluate the safety, tolerability, and efficacy of olaparib in pediatric patients with refractory solid tumors and to recommend a dose for phase II trials.

Methods

In this open-label, multicenter study, olaparib tablets (62.5, 125, and 187.5 mg/m² b.i.d.) will be administered orally in a standard 3 + 3 dose escalation design. Patients aged 3 to 18 years with recurrent pediatric solid tumors are eligible. Pharmacokinetic and pharmacodynamic analyses will also be performed.

Discussion

This study aims to extend the indications for olaparib by assessing its safety and efficacy in pediatric refractory solid tumor patients.

Trial registration

UMIN-CTR (UMIN000025521); Registered on January 4, 2017.

CircHMGCS1 Promotes Hepatoblastoma Cell Proliferation by Regulating the IGF Signaling Pathway and Glutaminolysis

Circular RNAs (circRNAs), a novel class of endogenous RNAs, have been recently shown to participate in cellular development and several pathophysiological processes. The identification of dysregulated circRNAs and their function in cancer have attracted considerable attention. Nevertheless, the expression profile and role of circRNAs in human hepatoblastoma (HB) remain to be studied. In this report, we analyzed the expression prolife of circRNAs in HB tissues and identified circHMGCS1 (3-hydroxy-3-methylglutaryl-CoA synthase 1; hsa_circ_0072391) as a remarkably upregulated circRNA. Methods: The expression prolife of circRNAs in HB tissues were investigated through circRNA sequencing analyses. ISH and qRT-PCR assays were performed to measure the expression level of circHMGCS1. The effect of knocking down circHMGCS1 in HB cells in vitro and in vivo were evaluated by colony formation assay, flow cytometry, xenograft tumors assay and untargeted metabolomics assay. MRE analysis and dual luciferase assay were performed to explore the underlying molecular mechanisms. Results: HB patients with high circHMGCS1 expression have shorted overall survival. Knockdown of circHMGCS1 inhibits HB cells proliferation and induces apoptosis. CircHMGCS1 regulates IGF2 and IGF1R expression via sponging miR-503-5p, and affects the downstream PI3K-Akt signaling pathway to regulate HB cell proliferation and glutaminolysis. Conclusions: The circHMGCS1/miR-503-5p/IGF-PI3K-Akt axis regulates the proliferation, apoptosis and glutaminolysis of HB cells, implying that circHMGCS1 is a promising therapeutic target and prognostic marker for HB patients.

Pulmonary Metastasectomy in Pediatric Solid Tumors

Metastatic disease and the complications of treating metastatic disease are the primary causes of mortality in children with solid malignancies. Nearly 25% of children with solid tumors have metastatic disease at initial diagnosis and another 20% develop metastases during or after treatment. The most common location of these metastases is the lung. The role of surgery in metastatic disease depends greatly on the histology of the primary. In general, tumors that are refractory to adjuvant therapies are most appropriate for pulmonary metastasectomy. This article will summarize the indications for metastasectomy in pediatric solid tumors and discuss the ongoing debate over the technique of metastasectomy in osteosarcoma.

Treatment outcome and pattern of failure in hepatoblastoma treated with a consensus protocol in Hong Kong

BACKGROUND AND AIM

We reviewed the results and pattern of failure of the consensus HB/HCC 1996 treatment protocol for pediatric hepatoblastoma (HB) in Hong Kong. The role of SIOPEL and Children's Hepatic tumors International Collaboration (CHIC) risk stratification was evaluated.

METHODS

Patients enrolled on the protocol from 1996 to 2014 were included. PRETEXT staging, SIOPEL, and CHIC risk groups were retrospectively assigned.

RESULTS

Sixty patients were enrolled with median age at diagnosis of 1.1 years and median follow-up time of 6.8 years. Alpha-fetoprotein (AFP) was raised (>100 ng/mL) in 58 (97%) patients. Five (8%) had metastases at presentation and 7 (12%) experienced tumor rupture prior to or during treatment. Twenty-nine patients (48%) received a first-line cisplatin, 5-fluorouracil, and vincristine regimen only while 23 (38%) also had alternative chemotherapeutic agents. Hepatic resection could be performed in 48 (80%) patients. Three (5%) patients underwent upfront liver transplantation. Five-year event-free survival and overall survival rates were 69.2% ± 6.1% and 77.6% ± 5.5% respectively. Among the 16 patients with relapse/progression, 9 had intrahepatic failure only, 5 had distant failure only, and 2 had combined local and distant failure. Predictors of inferior outcome included advanced Evans staging, disease involving both lobes, rupture, low AFP, and suboptimal response to first-line chemotherapy. Assigned in 44 patients, PRETEXT staging, SIOPEL, and CHIC risk groups significantly predicted EFS and OS.

CONCLUSIONS

Although the consensus HB/HCC 1996 protocol led to cure in three-quarters of pediatric HB patients, an upfront risk stratification system is required to identify and improve the outcome of high-risk patients.

Hepatoblastoma in a Child With Early-onset Cirrhosis

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

Targeting PIM Kinases Affects Maintenance of CD133 Tumor Cell Population in Hepatoblastoma

Hepatoblastoma is the most common primary liver tumor in children, but treatment has not changed significantly in the past 20 years. We have previously demonstrated that Proviral Integration site for Moloney murine leukemia (PIM) kinases promote tumorigenesis in hepatoblastoma. Stem cell-like cancer cells (SCLCCs) are a subset of cells thought to be responsible for chemoresistance, metastasis, relapse, and recurrence. The aim of this study was to identify SCLCCs in hepatoblastoma and determine the role of PIM kinases in SCLCCs. Hepatoblastoma cells were separated into CD133-enriched and CD133-depleted populations and the frequency of SCLCCs was assessed. CD133 expression was determined in the presence or absence of the PIM inhibitor, AZD1208. The effects of AZD1208 on proliferation, apoptosis, and motility were assessed in vitro and the effect of AZD1208 on tumor growth was examined in vivo. We identified CD133 as a marker for SCLCCs in hepatoblastoma and showed that PIM kinases promote a SCLCC phenotype. PIM kinase inhibition with AZD1208 decreased proliferation, migration, and invasion and increased apoptosis in both SCLCCs and non-SCLCCs in a long-term passaged hepatoblastoma cell line and patient-derived xenograft. Additionally, tumor growth in mice implanted with hepatoblastoma SCLCCs was decreased with PIM inhibition such that 57% of the tumors regressed. These findings identify CD133 as a marker for SCLCCs in hepatoblastoma and provide evidence that inhibition of PIM kinases decreases stemness and tumorigenicity of SCLCCs in hepatoblastoma, making them potential therapeutic targets for the treatment of hepatoblastoma.

The role of pulmonary metastasectomy for hepatoblastoma in children with metastasis at diagnosis: Results from the JPLT-2 study

BACKGROUND/PURPOSE

The purpose of this study was to clarify the role of pulmonary metastasectomy in hepatoblastomas with lung metastasis at diagnosis. We reviewed cases enrolled in the JPLT-2 study.

METHODS

A total of 360 cases with hepatoblastoma were enrolled. The clinical courses and outcome of 60 cases with pulmonary metastasis at diagnosis were reviewed, focusing on metastasectomy.

RESULTS

Induction chemotherapy resulted in eradication of nodules in 26, residual nodules in 33, and early treatment-related death in one. Of the 33 cases with residual nodules, 11 underwent complete resection of the lung lesions, and among these, progression was reported in five. Complete resection of the liver tumor was not achieved in two of these. Three underwent incomplete resection of lung nodules, eventually leading to progression. Twelve cases with incomplete or no liver tumor resection progressed regardless of the status of lung lesions. Contrarily, among patients who underwent complete resection of the liver tumor, half were cured without metastasectomy.

CONCLUSIONS

Metastasectomy for residual pulmonary nodules after induction chemotherapy is effective provided that the liver tumor could be completely resected.

TYPE OF STUDY

Prospective Cohort Study.

LEVEL OF EVIDENCE

Level II.