Management of undifferentiated embryonal sarcoma of the liver: A Pediatric Surgical Oncology Research Collaborative study

BACKGROUND

Undifferentiated embryonal sarcoma of the liver (UESL) is a rare tumor for which there are few evidence-based guidelines. The aim of this study was to define current management strategies and outcomes for these patients using a multi-institutional dataset curated by the Pediatric Surgical Oncology Research Collaborative.

METHODS

Data were collected retrospectively for patients with UESL treated across 17 children's hospitals in North America from 1989 to 2019. Factors analyzed included patient and tumor characteristics, PRETEXT group, operative details, and neoadjuvant/adjuvant regimens. Event-free and overall survival (EFS, OS) were the primary and secondary outcomes, respectively.

RESULTS

Seventy-eight patients were identified with a median age of 9.9 years [interquartile range [IQR): 7-12]. Twenty-seven patients underwent resection at diagnosis, and 47 patients underwent delayed resection, including eight liver transplants. Neoadjuvant chemotherapy led to a median change in maximum tumor diameter of 1.6 cm [IQR: 0.0-4.4] and greater than 90% tumor necrosis in 79% of the patients undergoing delayed resection. R0 resections were accomplished in 63 patients (81%). Univariate analysis found that metastatic disease impacted OS, and completeness of resection impacted both EFS and OS, while multivariate analysis revealed that R0 resection was associated with decreased expected hazards of experiencing an event [hazard ratio (HR): 0.14, 95% confidence interval (CI): 0.04-0.6]. At a median follow-up of 4 years [IQR: 2-8], the EFS was 70.0% [95% CI: 60%-82%] and OS was 83% [95% CI: 75%-93%].

CONCLUSION

Complete resection is associated with improved survival for patients with UESL. Neoadjuvant chemotherapy causes minimal radiographic response, but significant tumor necrosis.

A Case Report and a Review of Pediatric Hepatoblastoma

Introduction

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

Case Presentation

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

Conclusion

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

Elevated serum uric acid is associated with the risk of advanced staging and vascular involvement in patients with hepatoblastoma: a 14-year retrospective study

Background

Uric acid is the end product of the purine metabolism pathway, and has been linked to cancer risks and prognosis, but its relationship with hepatoblastoma (HB) remains unclear. This study aims to investigate the association between serum uric acid (SUA) and the advanced tumor staging and unfavorable extra-parenchymal tumor characteristics in patients with HB.

Methods

This study enrolled pediatric patients from Xinhua Hospital between 2007 to 2021. A total of 101 participants with newly diagnosed HB were recruited in the study. PRETreatment EXTent of disease (PRETEXT)/PostTreatment Extent of disease (POSTTEXT) staging were evaluated at diagnosis and following neoadjuvant chemotherapy (NAC). Adjusted smoothing spline plots, subgroup analysis and multivariate logistic regression analysis were conducted to estimate the association of different levels of SUA with the advanced tumor staging and present annotation factors.

Results

In accordance with SUA tertiles, those patients with higher pretreatment SUA levels showed increased percentages of PRETEXT group IV, vessel involvement and multifocality of tumors. After fully adjustment with the confounding factors, SUA was positively associated with advanced PRETEXT stage IV (OR: 1.72, 95%CI 1.15-2.57, p=0.0080), as well as vascular invasion (OR: 1.29, 95%CI 1.01-1.64, p=0.0396). Compared with the lowest SUA concentration tertile, the highest tertile were independently associated with vessel involvement of tumor in all of the adjusted models. Following NAC, SUA levels were significantly reduced in response to the downstaging of tumors. SUA remained positively associated with advanced POSTTEXT staging and vessel involvement in adjusted models. Patients with highest tertile of posttreatment SUA showed worse 5-year EFS and OS.

Conclusion

Elevated SUA were associated with an increased occurrence of advanced PRETEXT/POSTTEXT staging and unfavorable vessel involvement at diagnosis and following NAC in patients with HB. High posttreatment SUA reflected poor tumor responses to NAC. This study linked SUA, a non-invasive laboratory test, with tumor staging and risk prediction for HB.

Recent improvement in survival outcomes and reappraisal of prognostic factors in hepatoblastoma

Background

Prognostic factors in hepatoblastoma need to be reevaluated considering the advances in treatment modalities. The study aimed to evaluate current outcomes of hepatoblastoma and reappraise the association of prognostic factors, including pre‐treatment extent of tumor (PRETEXT) stage with annotation factors and Children's Hepatic tumors International Collaboration‐Hepatoblastoma Stratification (CHIC‐HS) system, with survival outcomes.

Methods

We evaluated 103 consecutive patients with hepatoblastoma retrospectively according to the treatment period based on the introduction of a liver transplantation program.

Results

The 5‐year overall survival (OS), event‐free survival (EFS), and transplant‐free survival rates were 80.2%, 74.2%, and 61.8%, respectively. EFS and OS were improved significantly from 58.6% to 81.6% (P = 0.024) and from 58.6% to 90.8% (P < 0.001), respectively, in the late period (N = 74) compared with the early period (N = 29). The PRETEXT stage was significant or marginally significant for EFS and OS in the early period but not in the late period. The P, F, R, and C factors were significant for OS and EFS in the early period. However, in the late period, only the P factor was significant for OS, and the F and M factors were significant for EFS. The CHIC‐HS system was significant or marginally significant for EFS in both the early and late periods; however, it was significant for OS only in the early period.

Conclusion

Survival rates were significantly improved in children with hepatoblastoma, especially in those with advanced PRETEXT stages with positive annotation factors and in a high‐risk CHIC‐HS group. Prognostic factors had different clinical implications with evolved treatment modalities.

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.

Children's Hepatic Tumors International Collaboration-Hepatoblastoma Stratification (CHIC-HS) System for Pediatric Patients with Hepatoblastoma: A Retrospective, Hospital-Based Cohort Study in South Korea

Purpose

In 2017, the Children's Hepatic Tumors International Collaboration-Hepatoblastoma Stratification (CHIC-HS) system was introduced. We aimed to evaluate the accuracy of Children's Hepatic Tumors International Collaboration-Hepatoblastoma Stratification (CHIC-HS) System for the prediction of event-free survival in Korean pediatric patients with hepatoblastoma.

Materials and Methods

This two-center retrospective study included consecutive Korean pediatric patients with histopathologically confirmed hepatoblastoma from March 1988 through September 2019. We compared event-free survival (EFS) among four risk groups according to the CHIC-HS system. Discriminatory ability of CHIC-HS system was also evaluated using optimism-corrected C-statistics. Factors associated with EFS were explored using multivariable Cox regression analysis.

Results

We included 129 patients (mean age, 2.6±3.3 years; female:male, 63:66). The 5-year EFS rates in the very low, low, intermediate, and high-risk groups, according to the CHIC-HS system were 90.0%, 82.8%, 73.5%, and 51.3%, respectively. The CHIC-HS system aligned significantly well with EFS outcomes (p=0.004). The optimism-corrected C index of CHIC-HS was 0.644 (95% CI, 0.561-0.727). Age ≥8 (vs. age ≤2; HR, 2.781; 95% CI, 1.187-6.512; p=0.018), PRE-Treatment EXTent of tumor (PRETEXT) stage IV (vs. PRETEXT I or II; HR, 2.774; 95% CI, 1.228-5.974; p=0.009), and presence of metastasis (HR, 2.886; 95% CI, 1.457-5.719; p=0.002), which are incorporated as the first three nodes in the CHIC-HS system, were independently associated with EFS.

Conclusion

The CHIC-HS system aligned significantly well with EFS outcomes in Korean pediatric patients with hepatoblastoma. Age group, PRETEXT stage, and presence of metastasis were independently associated with EFS.

Clinicopathological profile of hepatoblastoma: An experience from a tertiary care center in India

Background

Hepatoblastoma is the most common primary hepatic malignancy in the pediatric population. Advances in pathological evaluation, imaging, risk stratification, neo-adjuvant chemotherapy, and surgery including transplantation have improved survival of these children in the western countries. However, a successful outcome in developing countries such as India with limited resources poses great challenges to the clinician and the family. Histology plays a major role in determining the prognosis of these patients.

Methods

A retrospective study was done on 10 children diagnosed with hepatoblastoma between January 2010 and December 2015 in our institution. Clinical, laboratory, radiological, histopathological diagnoses, treatment, and outcome data were collected and analyzed.

Results

The median age of these children at diagnosis was 11 months, and only 1 child was premature at birth. Most children were presented with abdominal distension. One child had lung metastasis at presentation. Elevated alpha fetoprotein levels were present in 90% of the children. The histological types were fetal, embryonal, macrotrabecular, and mixed epithelial-mesenchymal types. SIOPEL risk stratification was done, which showed 40% of the children to be of high risk. Three children had PRETEXT 1, 2, and 4, respectively.

Conclusion

Our study is significant with respect to the information on PRETEXT staging, risk status, and histological favorability. In developing countries with limited resources and low-socioeconomic status, it is important to have a multidisciplinary team approach and tailor treatment to manage these patients effectively and improve the overall survival.

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.

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.

Hepatoblastoma: current understanding, recent advances, and controversies

Introduction: Hepatoblastoma (HB) is the most common primary malignant liver neoplasm in children. Its increasing survival rate is related to the progress in modern imaging, surgical techniques, and new chemotherapy regimens.

Clinical approach: One of the past achievements was the development of the pretreatment extension of disease (PRETEXT) system. Gradually, the HB therapeutic approach has become more individualized with better stratification of patients.

Controversies: These include the need for preoperative chemotherapy and its optimal duration; intensity of preoperative chemotherapy required for locally advanced cases (PRETEXT 4); optimal surgical treatment for locally advanced tumors: aggressive hepatic resections versus liver transplantation; the role of postoperative chemotherapy in the post-transplant setting; the timing and role of metastasectomy in patients with disseminated disease who undergo partial liver resection; and the prognostic significance of several HB pathology variants.

Hepatoblastoma biology: Beta-catenin mutations and the beta-catenin/Wnt pathway play an important role in HB development. There have been at least two molecular signatures in HB published. Unluckily, all of these findings are based on relatively small clinical series and require confirmation.

Conclusion: The treatment of HB started from one and the same therapy for all patients and aimed at increased treatment individualization, but the future seems to lie in biology-driven patient-tailored therapies.

Contrast-enhanced CT features of hepatoblastoma: Can we predict histopathology?

BACKGROUND

Hepatoblastoma is the most common hepatic malignancy occurring in the pediatric population. Intratumoral cellular behavior varies, and the small-cell undifferentiated histopathology carries a poorer prognosis than other tissue subtypes. Neoadjuvant chemotherapy is recommended for this tumor subtype prior to surgical resection in most cases. Early identification of tumors with poor prognosis could have a significant clinical impact. Objective The aim of this work was to identify imaging features of small-cell undifferentiated subtype hepatoblastoma that can help distinguish this subtype from more favorable tumors and potentially guide the clinical management. We also sought to characterize contrast-enhanced CT (CECT) features of hepatoblastoma that correlate with metastatic disease and patient outcome.

MATERIALS AND METHODS

Our study included 34 patients (24 males, 10 females) with a mean age of 16months (range: 0-46months) with surgically confirmed hepatoblastoma and available baseline abdominal imaging by CECT. Clinical data and CT abdominal images were retrospectively analyzed.

RESULTS

Five tumors with small-cell undifferentiated components were identified. All of these tumors demonstrated irregular margins on CT imaging. Advanced PRETEXT stage, vascular invasion and irregular margins were associated with metastatic disease and decreased survival. Capsular retraction was also significantly associated with decreased survival. Irregular tumor margins demonstrated statistically significant association with the presence of small-cell undifferentiated components. No other imaging feature showed statistically significant association.

CONCLUSION

Tumor margin irregularity, vascular invasion, capsular retraction, and PRETEXT stage correlate with worse patient outcomes. Irregular tumor margin was the only imaging feature significantly associated with more aggressive tumor subtype.

The treatment of hepatoblastoma: Its evolution and the current status as per the SIOPEL trials

Aim of the Review:

To describe the significant improvement in the diagnosis, treatment and outcome of children diagnosed with hepatoblastoma (HB) that has occurred in the past four decades. Recent findings are mainly focused on lessons learned from the experiences of the Childhood Liver Tumors Strategy Group (SIOPEL). Important milestones were the risk stratification of HB that allowed to tailor down therapy for standard-risk HB and intensify treatment for high-risk HB. The multi-institutional international cooperative SIOPEL trials are reviewed and current treatment guidelines are given. Intensified cooperation between the SIOPEL and the Children's Oncology Group (COG) and the national study groups from Germany (GPOH) and Japan (JPLT) led to the acceptance and use of one staging system (PRETEXT) and the formation of a single robust database containing data of 1605 HB patients. This will allow analysis with enough statistical power of treatment directing factors that will form one of the bases of the next-generation clinical trial that is currently designed by all four collaborating study groups.

Summary:

Successive SIOPEL trials and increasing international collaboration have improved survival rates of patients with HB through risk stratification, advances in chemotherapy and increased complete resection rates including liver transplantation as a surgical option.