Microscopically positive resection margin after hepatoblastoma resection: what is the impact on prognosis? A Childhood Liver Tumours Strategy Group (SIOPEL) report

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

IMPACT

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

Surgical management of liver tumors

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

Digital medicine and minimally invasive surgery in pediatric hepatoblastoma: An update

Hepatoblastoma (HB) is the most common liver malignancy in children, accounting for approximately 60 % of liver tumors in this population. However, the exact cause of HB remains unclear. The combination of surgery and neoadjuvant chemotherapy has significantly improved the overall survival rate of children with HB, increasing it from 40 % in the past to over 70 %. The concept of precise hepatectomy, which aims to achieve the best rehabilitation outcomes with minimal trauma and maximum liver protection, has been widely accepted by hepatobiliary surgeons. This article provides a comprehensive review of the recent advancements in surgical treatment of HB, focusing on digital surgery and minimally invasive techniques.

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

BACKGROUND

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSION

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

Risk for Recurrence in Long-Term Follow-Up of Children after Liver Transplantation for Hepatoblastoma or Hepatocellular Carcinoma

The aim of this study was to assess the long-term results of liver transplantation (LT) in pediatric patients with unresectable hepatoblastoma (HB) or hepatocellular carcinoma (HCC) with special reference to the risk of tumor recurrence. We retrospectively analyzed data from 46 HB and 26 HCC patients who underwent LT between 1990 and 2022. In HCC patients, we compared outcomes depending on donor type. We evaluated the impact of a number of risk factors on recurrence-free survival after LT. Estimated patient survival after 5, 10, and 15 years was 82%, 73%, and 73% in the HB group and 79%, 75%, and 75% in the HCC group, respectively (p = 0.76). In the HCC group, living donor LT (LDLT) and deceased donor LT (DDLT) provided similar patient survival (p = 0.09). Estimated recurrence-free survival in patients who had three or fewer risk factors was significantly better than in patients with more than three risk factors (p = 0.0001). Adequate patient selection is necessary when considering LT for primary liver tumors in children. The presence of more than three risk factors is associated with a very high risk of recurrence and indicates poor prognosis, whereas extrahepatic disease may be considered a contraindication for transplantation.

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.

Successful Treatment for Hepatoblastoma in Trisomy 18: A Case Report

Children with trisomy 18 tend to develop hepatoblastoma. Since the introduction of appropriate management for organ malfunction, individuals with trisomy 18 have come to have a longer life expectancy. However, the predisposition to hepatoblastoma becomes a significant issue for the quality of a case. Here, we present a rare multifocal hepatoblastoma involving predominantly Couinaud segments 5 and 7 in a 10-month-old boy with trisomy 18. Though the first-line cisplatin monotherapy resulted in unsatisfactory tumor shrinkage, the second-line neoadjuvant chemotherapy administrating irinotecan and vincristine gave rise to significant tumor reduction in volume, leading to the completion of partial resection of the liver without the microscopic residual disease. The patient has been free from recurrence for 44 months. Because anatomical right hepatectomy can cause circulatory instability, including acute onset of pulmonary hypertension in trisomy 18 patients, physicians should balance treatment benefits and potential adverse effects. Our successful experience utilizing a combination of efficacious and less cardiotoxic neoadjuvant chemotherapy followed by the partial hepatectomy encourages physicians to treat a patient with trisomy 18 and tackle hepatoblastoma with a genetic background.

Parenchyma Sparing Anatomic Liver Resections (Bi- and Uni-Segmentectomies) for Liver Tumours in Children-A Single-Centre Experience

Purpose: To present a single-centre experience in bi- and uni-segmentectomies for primary liver tumours in children.

METHODS

This study included 23 patients that underwent (bi)segmentectomy. There were 15 malignant tumours (hepatoblastoma-13 patients), 7 benign tumours, and 1 calcifying nested stromal epithelial tumour.

RESULTS

The median tumour diameter was 52 mm (range 15-170 mm). Bisegmentectomy 2-3 was most frequently performed (seven patients), followed by bisegmentectomy 5-6 (four patients). The median operative time was 225 min (range 95-643 min). Intraoperative complications occurred in two patients-small bowel perforation in one and an injury of the small peripheral bile duct resulting in biloma in the other. The median resection margin in patients with hepatoblastoma was 3 mm (range 1-15 mm). Microscopically negative margin status was achieved in 12 out of 13 patients. There were two recurrences. After a median follow-up time of 38 months (range 12-144 months), all 13 patients with HB were alive with no evidence of disease. Two relapsed patients were alive with no evidence of disease.

CONCLUSIONS

From the available literature and data presented here, we propose that (bi)segmentectomy can become a viable surgical option in carefully selected paediatric patients and is sufficient to achieve a cure. Further studies evaluating the impact of parenchymal preservation surgery on surgical and oncological outcome should be conducted with a larger dataset.

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.

Strategy for hepatoblastoma with major vascular involvement: A guide for surgical decision-making

BACKGROUND

Surgical management of tumor thrombus extending to the major vascular system for children with hepatoblastoma is challenging and insufficiently discussed.

METHODS

We conducted a retrospective review of hepatoblastoma with tumor thrombus extending to the major vascular system (inferior vena cava, 3 hepatic veins, and portal vein trunk) treated at our center between May 2010 and June 2021. We describe our preoperative assessment, surgical strategies, and outcomes.

RESULTS

We identified 9 patients (median age at the diagnosis: 3.4 years). All patients received chemotherapy before liver surgery. At the time of the diagnosis, tumor thrombus extended to the portal vein trunk (n = 6), inferior vena cava (n = 3), and 3 hepatic veins (n = 2). Among the 9 patients, 4 underwent liver resection. Liver transplantation was performed in 5 patients. The inferior vena cava wall was circumferentially resected for tumor removal in 1 patient and partially resected in 2 patients. One patient underwent liver transplantation using veno-venous bypass. Patients with tumor thrombus extending to the portal vein trunk were more likely to be managed by liver transplantation in comparison to those with tumor thrombus spreading to the inferior vena cava. The median follow-up period was 5.5 years. One patient underwent transhepatic balloon dilatation for biliary stricture after liver resection. Tumor recurrence was seen in 3 patients (33.3%; lung, n = 2; lymph node and liver, n = 1). No patients died during the follow-up period.

CONCLUSION

Surgical intervention for pediatric hepatoblastoma with tumor thrombus extending into the major vascular system is safe, feasible, and achieves excellent outcomes.

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 nomogram model to predict prognosis of patients with hepatoblastoma

BACKGROUND

Hepatoblastomas (HBs) are malignant liver tumors that most commonly develop in pediatric patients. Microvascular invasion may be a prognosis factor for patients with HBs. This study aimed to construct a model to predict the survival outcome in HBs.

METHODS

We retrospectively analyzed the clinical data of 311 patients with HBs who underwent surgical resection at our institution between June 2014 and August 2021. First, patients were divided into two groups: those who had pathologic microvascular invasion (n = 146) and those who did not (n = 165). Propensity score-matched (PSM) analysis was carried out between the two groups. The preoperative parameters and overall survival (OS) rate were compared between the two groups. Second, all 311 patients were randomly divided into the training and validation cohort in a ratio of 4:1. A nomogram was created in the training cohort to visualize the prediction of OS. Moreover, the validation cohort was used for validation.

RESULTS

Multivariate analysis suggested that age, histology type, microvascular invasion, multifocality, distant metastasis, and macrovascular involvement are independent prognostic factors for HBs. The nomogram showed good predictive ability in the training and validation cohorts with a C-index of 0.878 (95% CI, 0.831-0.925) and 0.847 (95% CI, 0.757-0.937), respectively. The calibration curve indicated good agreement between the prediction and observation for one-, two-, and three-year OS probabilities.

CONCLUSION

By combining preoperative imaging results and other clinical data, we established a nomogram to predict OS probability for patients with HB, which could be a potential tool to guide personalized treatment.

A Novel Method for Observing Tumor Margin in Hepatoblastoma Based on Microstructure 3D Reconstruction

Objective: We investigated three-dimensional (3 D) reconstruction for the assessment of the tumor margin microstructure of hepatoblastoma (HB). Methods: Eleven surgical resections of childhood hepatoblastomas obtained between September 2018 and December 2019 were formalin-fixed, paraffin-embedded, serially sectioned at 4 μm, stained with hematoxylin and eosin (every 19th and 20th section stained with alpha-fetoprotein and glypican 3), and the digital images of all sections were acquired at 100× followed by image registration using the B-spline based method with modified residual complexity. Reconstruction was performed using 3 D Slicer software. Results: The reconstructed orthogonal 3 D images clearly presented the internal microstructure of the tumor margin. The rendered 3 D image could be rotated at any angle. Conclusions: Microstructure 3 D reconstruction is feasible for observing the pathological structure of the HB tumor margin.

Application of 3D Simulation Software in Chemotherapy and Hepatoblastoma Surgery in Children

Purpose

This study aims to explore the clinical value of a computer-assisted surgery system (Hisense CAS) in hepatoblastoma (HB) surgery in children after neoadjuvant chemotherapy.

Patients and Methods

The clinical medical records of children with HB treated after neoadjuvant chemotherapy at the Affiliated Hospital of Qingdao University from January 2016 to January 2019 were analyzed retrospectively.

Results

A total of 21 children were enrolled in this study, including 13 boys and 8 girls. All cases successfully underwent three-dimensional (3D) reconstruction of the liver and tumor using Hisense CAS, simulated hepatectomy, and hepatectomy according to the preoperative operation plan. There were twelve cases of right hemihepatectomy, four cases of right trefoil hepatectomy, one case of left lobe hepatectomy, and three cases of middle lobe hepatectomy, and one case of V and VI segment hepatectomy. All children recovered well after the operation. The follow-up ranged from 5 months to 3 years. One child died of systemic metastasis 8 months after the operation. One child received one course of chemotherapy after the operation. Due to the serious reaction to the chemotherapy, the family refused further treatment and follow-up. The remaining 19 children had no complications or recurrence.

Conclusion

Hisense CAS can clearly and intuitively display the position and shape of the HB before and after chemotherapy and its relationship with the intrahepatic pipeline system and accurately evaluate the changes in tumor volume and the distance between important blood vessels, which is conducive to the operator selecting the best operation opportunity, timely formulating the best operation plan and implementing individualized and accurate liver tumor resection.

The Role of N6-Methyladenosine in the Promotion of Hepatoblastoma: A Critical Review

Simple Summary

Hepatoblastoma is the most common malignant pediatric tumor of the liver. Unlike hepatocellular carcinoma (HCC) which has been associated with hepatitis B virus infection or cirrhosis, the etiology of hepatoblastoma remains vague. Genetic syndromes, including familial adenomatous polyposis (FAP), Beckwith-Wiedemann syndrome (BWS), and trisomy 18 syndrome, have been associated with hepatoblastoma. BWS is an overgrowth syndrome which exhibits an alteration of genomic imprinting on chromosome 11p15.5. N⁶-Methyladenosine (M⁶A) is an RNA modification with rampant involvement in the metabolism of cells and malignant diseases. It has been observed to impact the development of various cancers via its governance of gene expression. Here, we explore the role of m⁶A and its genetic associates in promoting HB, and the impact this may have on our future management of the disease.

Abstract

Hepatoblastoma (HB) is a rare primary malignancy of the developing fetal liver. Its course is profoundly influenced by genetics, in the context of sporadic mutation or genetic syndromes. Conventionally, subtypes of HB are histologically determined based on the tissue type that is recapitulated by the tumor and the direction of its differentiation. This classification is being reevaluated based on advances on molecular pathology. The therapeutic approach comprises surgical intervention, chemotherapy (in a neoadjuvant or post-operative capacity), and in some cases, liver transplantation. Although diagnostic modalities and treatment options are evolving, some patients experience complications, including relapse, metastatic spread, and suboptimal response to chemotherapy. As yet, there is no consistent framework with which such outcomes can be predicted. N⁶-methyladenosine (m⁶A) is an RNA modification with rampant involvement in the normal processing of cell metabolism and neoplasia. It has been observed to impact the development of a variety of cancers via its governance of gene expression. M⁶A-associated genes appear prominently in HB. Literature data seem to underscore the role of m⁶A in promotion and clinical course of HB. Illuminating the pathogenetic mechanisms that drive HB are promising additions to the understanding of the clinically aggressive tumor behavior, given its potential to predict disease course and response to therapy. Implicated genes may also act as targets to facilitate the evolving personalized cancer therapy. Here, we explore the role of m⁶A and its genetic associates in the promotion of HB, and the impact this may have on the management of this neoplastic disease.

Surgical resection of pediatric PRETEXT III and IV hepatoblastoma: A retrospective study investigating the need for preoperative chemotherapy

OBJECTIVE

This study analyzed the feasibility of upfront surgical resection for pediatric PRETEXT III and IV hepatoblastoma (HB).

SUMMARY BACKGROUND DATA

Neoadjuvant chemotherapy is recommended for patients with PRETEXT III and IV HB to obtain a chance of curative surgery. However, chemotherapy can cause toxic side effects and adverse outcomes, and the PRETEXT staging system may overstage the patients. Therefore, whether preoperative chemotherapy is necessary for HB patients remains unclear.

METHODS

The clinical data of 37 children who underwent surgical resection for PRETEXT III and IV HB at our hospital were obtained retrospectively. Patients were divided into the neoadjuvant chemotherapy group (NCG; n = 19) and the routine surgery group (RSG; n = 18). Clinicopathologic characteristics, treatment regimens, and outcomes were compared between the groups.

RESULTS

The RSG had a lower incidence of portal vein involvement than the NCG (p < 0.002). The estimated 3-year event-free survival rates were similar (RSG: 89 ± 0.7% and NCG: 79 ± 0.9%, p = 0.3923). The RSG underwent fewer courses of chemotherapy than the NCG (five vs. six; p < 0.001). Furthermore, the RSG had lower incidences of febrile neutropenia, myelosuppression, and gastrointestinal reactions (all p < 0.05). The severity of surgery-related complications did not differ significantly.

CONCLUSION

Upfront surgical resection in children with PRETEXT III and IV HB is safe and feasible, and reduces the total number of courses and side effects of chemotherapy. The degree of vascular involvement is the most important consideration when evaluating resectability during diagnosis.

Mitochondrial fragmentation is crucial for c-Myc-driven hepatoblastoma-like liver tumor

Hepatoblastoma is the most common liver cancer in children, and the aggressive subtype often has a poor prognosis and lacks effective targeted therapy. Although aggressive hepatoblastoma (HB) is often accompanied by abnormally high expression of the transcription factor c-Myc, the underlying mechanism remains unclear. In this study, we found that mitochondrial fragmentation was enhanced by c-Myc overexpression in human aggressive HB tissues and was associated with poor prognosis. Then, a mouse model resembling human HB was established via hydrodynamic injection of c-Myc plasmids. We observed that liver-specific knockout of the mitochondrial fusion molecule MFN1 or overexpression of mitochondrial fission molecule DRP1 promoted the occurrence of c-Myc-driven liver cancer. In contrast, when MFN1 was overexpressed in the liver, tumor formation was delayed. In vitro experiments showed that c-Myc transcriptionally upregulated the expression of DRP1 and decreased MFN1 expression through upregulation of miR-373-3p. Moreover, enhanced mitochondrial fragmentation significantly promoted aerobic glycolysis and the proliferation of HB cells by significantly increasing reactive oxygen species (ROS) production and activating the RAC-alpha serine/threonine-protein kinase (AKT)/mammalian target of rapamycin (mTOR) and nuclear factor κB (NF-κB) pathways. Taken together, our results indicate that c-Myc-mediated mitochondrial fragmentation promotes the malignant transformation and progression of HB by activating ROS-mediated multi-oncogenic signaling.

[Analysis of future liver remnant parameters in children after extended liver resection]

OBJECTIVE

To analyze the initial data on future liver remnant volume and its function evaluated by ^99mTc-Bromesida hepatobiliary scintigraphy in children with liver tumors.

MATERIAL AND METHODS

Extended liver resections were performed in 58 patients aged 2 months - 208 months (median 26 months) for various neoplasms. Before hepatectomy, all children underwent contrast-enhanced CT with volumetry and hepatobiliary scintigraphy with ^99mTc-Bromezida and subsequent quantitative assessment of its accumulation in the future liver remnant. All consecutive patients eligible for extended liver resection were retrospectively analyzed.

RESULTS

The analysis included patients who underwent extended liver resection between June 2017 and March 2021. Among 91 liver resections, 58 (64%) procedures were extended hepatectomies including 2 ALPPS procedures. Median volume of future liver remnant was 44.5% (16.5-91.4), median future liver remnant function - 10.14%/min/m² (1.8-30). Four patients with adequate liver function had insufficient volume of future liver remnant. Insufficient future liver remnant volume and its appropriate function were observed in 2 patients. Not life-threatening post-resection liver failure developed in 2 patients.

CONCLUSION

Evaluation of future liver remnant function is the most sensitive method to predict post-hepatectomy liver failure in children. The cut off value of future liver remnant volume in children is below 25% and probably below 16.5%. Further data collection and research are warranted to determine significant values. These data will contribute to define the new indications for two-staged hepatectomies in children.

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

Objective

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

Methods

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

Results

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

Conclusion

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

Living donor liver transplantation for hepatic malignancies in children

BACKGROUND

Living donor liver transplantation is a treatment option for unresectable hepatic tumors in children.

METHODS

We enrolled 45 living donor transplantations performed between 1993 and 2018 for liver malignacies, which included hepatoblastoma (n = 33), hepatocellular carcinoma (n = 10), hepatic angiosarcoma (n = 1), and rhabdomyosarcoma (n = 1).

RESULTS

No mortality or major morbidities were encountered in any donor, and the complication rate was 9%. In the hepatoblastoma group, 5-year overall and event-free survival rate in recipients was 87.4% and 75.8%, respectively, and mortality was significantly higher in patients after rescue transplantation (p = .001). Inferior vena cava replacement in these recipients appeared to be associated with reduced mortality (p = .034), but this was not confirmed when rescue patients were excluded (p = .629). In hepatocellular carcinoma group, both 5-year overall and event-free survival rates were 75.4% each, and invasion of hepatic veins was significantly associated with increased risk of recurrence and death (p = .028). The patient with rhabdomyosarcoma died from EBV-induced lymphoma 2 months after transplantation. The patient with angiosarcoma was in complete remission at the last follow-up. Overall, 5-year graft survival rate was 81.3%, and one patient underwent re-transplantation due to chronic rejection.

CONCLUSIONS

Pediatric oncological liver transplantation has become a key player in the management of malignancies with cancer cure in 84% of patients in this series. Living donor liver transplantation for pediatric recipients with unresectable tumors might be a beneficial surgical option, which is technically safe for donors and recipients, thus, allowing timely planning according to chemotherapy protocols.

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 retrospective study of clinical features and outcome in patients with refractory or recurrent hepatoblastoma: A single institution experience

BACKGROUND

Hepatoblastoma (HB) is the most common childhood primary hepatic malignancy. The overall survival rate in patients with HB has reached more than 80% over the past decades. The poor prognostic and high-risk HB have been defined, but the treatment and cure of refractory or relapsed HB is still an arduous task.

METHODS

The complete records of HB in patients under the age of 18 at the MacKay Memorial Hospital between 1990 and 2019 were examined.

RESULTS

The treatment results for 11 patients with refractory or relapsed HB are presented. The multi-modality treatment records were reviewed and the clinical characteristics associated with poor outcome included multifocal lesions, low α-fetoprotein, great vessel invasion and metastases. Delayed liver tumor surgery was carried out in eight cases. The median duration of follow-up for the 11 patients was 48.6 months (range 1.9 to 316.8 months). The 5-year and 10-year overall survival rate were 62.3% ± 15% (SE) and 49.9% ± 16.4% (SE), respectively. Most treatment-related toxicities were tolerable. The major concern during long term follow-up was irreversible high-frequency hearing loss.

CONCLUSION

Patients with refractory/relapsed HB are still a thorny issue and more research is needed to improve the outcome.

Advances in the conventional clinical treatment for hepatoblastoma and therapeutic innovation

Background

Hepatoblastoma (HB) is a rare malignancy usually occurring in children under 3 years old. With advancements in surgical techniques and molecular biology, new treatments have been developed.

Data resources

The recent literatures on new treatments, molecular mechanisms and clinical trials for HB were searched and reviewed.

Results

Surgical resection remains the main option for treatment of HB. Although complete resection is recommended, a resection with microscopical positive margins (R1) may have similar 5-year overall survival and 5-year event-free survival (EFS) rates after cisplatin chemotherapy and the control of metastasis, as only once described so far. Indocyanine green-guided surgery can help achieve precise resection. Additionally, associating liver partition and portal vein ligation for staged hepatectomy can rapidly increase future liver remnant volume compared with portal vein ligation or embolization. Cisplatin-containing chemotherapies slightly differ among the guidelines from the International Childhood Liver Tumors Strategy Group (SIOPEL), Children’s Oncology Group (COG) and Chinese Anti-Cancer Association Pediatric Committee (CCCG), and the 3-year EFS rate of patients in SIOPEL and CCCG studies was recently shown to be higher than that in COG studies. Liver transplantation is an option for patients with unresectable HB, and successful cases of autologous liver transplantation have been reported. In addition, effective inhibitors of important targets, such as the mTOR (mammalian target of rapamycin) inhibitor rapamycin, β-catenin inhibitor celecoxib and EpCAM (epithelial cell adhesion molecule) inhibitor catumaxomab, have been demonstrated to reduce the activity of HB cells and to control metastasis in experimental research and clinical trials.

Conclusion

These advances in surgical and medical treatment provide better outcomes for children with HB, and identifying novel targets may lead to the development of future targeted therapies and immunotherapies.

Feasibility of Nonanatomical Liver Resection in Diligently Selected Patients with Hepatoblastoma and Comparison of Outcomes with Anatomic Resection

INTRODUCTION

 Treatment guidelines for hepatoblastoma discourage nonanatomic liver resections. However, the evidence for this is inadequate and comes from a study performed almost two decades ago which additionally contained inherent limitations. This study aimed to assess the feasibility and oncologic outcomes of nonanatomic resections (NAR) performed in diligently selected patients and compare the results with anatomic resections (AR).

MATERIALS AND METHODS

 A total of 120 patients who underwent liver resections for hepatoblastoma between January 2008 and July 2019 were reviewed. Feasibility of NAR was based on postchemotherapy relations to vessels, site of the lesion, and possibility of achieving negative resection margins.

RESULTS

 AR was performed in 95 patients and 25 had NAR. The NAR cohort had similar International Childhood Liver Tumors Strategy Group (SIOPEL) risk group distribution. Blood loss and operative times were lower in patients undergoing NAR. No differences were noted between the two groups concerning postoperative morbidity and hospitalization. There were no pathologic positive margins or local recurrences in the NAR patients. Relapse free (RFS) and overall survival (OS) was similar in the two groups (p = 0.54 and 0.96, respectively). Subgroup analysis of only posttreatment extent of tumor (POSTTEXT) I and II patients also showed no difference in RFS or OS for the two groups with a persistent significant difference in operative times and blood loss.

CONCLUSION

 NAR is feasible with clear margins in carefully selected patients. It is not associated with more complications and outcomes are not inferior to AR. NAR is associated with lesser blood loss and operative time.

Liver Tumours in Children: The Hepatologist's View

ABSTRACT

Diagnostic and therapeutic innovations have changed the way we now approach liver tumours in children and adolescents. Novel imaging tools, increasing awareness, and surveillance has led to early diagnosis of benign and malignant liver tumours. Multidisciplinary interventions have favourably altered the natural course in some liver tumours. The role of liver transplantation is expanding and has become fully integrated into today's therapeutic algorithms. Transarterial locoregional and ablation therapies have been successful in adults and are being explored in children to facilitate resectability and improve outcome. For the first time, North American, Japanese, and European experts have designed a global trial to optimize management of malignant liver tumours and aim to find signature molecular profiles that will translate to individualised treatment strategies.This article aims to offer an overview of recent advances in our understanding of liver tumours in children. It focuses on the paediatric hepatologist's view and their role in the multidisciplinary management of benign and malignant liver tumours.

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.

[Therapeutic effect and clinical cost of multi-disciplinary team model of hepatoblastoma in children]

OBJECTIVE

To summarize and analyze the treatment process, long-term efficacy and clinical economics of children's hepatoblastoma (HB) in multi-disciplinary team (MDT) mode, so as to provide basis for the rational choice of diagnosis and treatment.

METHODS

From January 2014 to February 2019, 13 cases of hepatoblastoma in children who completed the whole treatment course in the Pediatric Hematology Tumor Ward of Peking University First Hospital were collected and analyzed, and were followed up until June 30, 2020. There were 9 males and 4 females who were diagnosed and treated according to the MDT process in the hospital. The median age was 16 months (2-54 months), 69.23% (9/13) were under 2 years old. The characteristics, diagnosis and treatment process and treatment effect of the cases were summarized, and the cost of clinical treatment was analyzed.

RESULTS

According to the pretreatment extent of disease(PRETEXT), there were 1, 9 and 3 children with stages Ⅱ, Ⅲ and Ⅳ. 76.92% (10/13) of the patients had the largest tumor diameter > 10 cm. All the patients received preoperative neoadjuvant chemotherapy (8 patients received 4 cycles of chemotherapy, and 6 patients changed the chemotherapy plan), surgical treatment and postoperative chemotherapy, the tumor volume decreased by more than 50% (64%-95%) in 12 cases, except 1 case with no significant increase of alpha fetal protein and multiple lesions.The median length of stay was 87 days (68-214 days), the median cost of stay was 200 000 yuan (115 000-500 000 yuan), the median length of stay was 7 days (5-17 days), the median cost of stay was 20 000 yuan (15 000-60 000 yuan), and the incidence of postoperative complications was 7.69% (1/13). All the patients were followed up for 16-69 months. All the patients survived.

CONCLUSION

Under the MDT mode, the treatment is seamless connection, the long-term prognosis of children with HB is good, and the total hospitalization cost and time are within the acceptable range. Standard preoperative neoadjuvant chemotherapy can significantly reduce the tumor, improve the resection rate, reduce postoperative complications, reduce the total individual expenditure, shorten the total hospital stay, and further improve the long-term disease-free survival rate.

Management of hepatoblastoma in the United States: Can we do better?

BACKGROUND

Hepatoblastoma is the most common type of liver cancer in children. Refined therapeutic approaches combining risk-adapted chemotherapy along with complete tumor resection has led to improved survival. We aimed to evaluate the current state of management and outcomes for hepatoblastoma in the United States.

METHODS

We retrospectively reviewed 794 children (<18 years) with hepatoblastoma from the National Cancer Database (2004-2015). We assessed overall survival by means of Kaplan-Meier method, log-rank tests, and multivariable Cox regression.

RESULTS

Median age was 1 year (interquartile range: 0-2) and 170 (21.4%) presented with metastatic disease. Surgical resection was included in the treatment of 614 (77.3%) children (resection in 66.8% and liver transplantation in 10.6%). In the entire cohort, 95.1% of children received chemotherapy. In the surgical cohort, 575 (93.6%) received chemotherapy (34.5% neoadjuvant, 28.7% adjuvant, 30.5% both neoadjuvant and adjuvant). The 5-year overall survival was 76.6% for the entire cohort (no-surgery group: 55.3% vs surgery group: 82.8%). In multivariable analysis for all children, age ≥8 years (P = .009), metastasis (P < .001), surgery only (P = .009), and chemotherapy only (P < .001) were risk factors for mortality. In multivariable analysis for the surgical cohort, metastasis (P = .001), multifocality (P = .02), no chemotherapy (P = .03), and margin-positive resection (P = .02) were risk factors for mortality.

CONCLUSION

Excellent long-term overall survival is achievable with a combination of chemotherapy and surgical resection when a negative resection margin is achieved. However, nearly a quarter of children never received surgical treatment, representing a potential opportunity for improvement in care.

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.

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.

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.

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.

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.

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.

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.