Primary malignant liver tumors in children

Integration of a dedicated management protocol in the care of pediatric liver cancer: From specialized providers to complication reduction

INTRODUCTION

Up to a third of children undergoing partial hepatectomy for primary hepatic malignancies experience at least one perioperative complication, with a presumed deleterious effect on both short- and long-term outcomes. We implemented a multidisciplinary treatment protocol in the management of these patients in order to improve complication rates following partial hepatectomy.

METHODS

A retrospective chart review was completed for all patients < 18 years of age who underwent liver resection at our institution between 2002 and 2019 for primary hepatic cancer. Demographic, intraoperative, postoperative, pathologic, and outcome data were analyzed for perioperative complications using the CLASSIC and Clavien-Dindo (CD) scales, event-free survival (EFS) and overall survival (OS).

RESULTS

A total of 73 patients were included in the analysis with 33 prior-to and 40 after dedicated provider protocol implementation. Perioperative complication rates decreased from 52% to 20% (p = 0.005) with major complications going from 18% to 10% (p = 0.31). On multivariable logistic regression, protocol implementation was associated with a reduction in any (OR 0.29 [95% CI 0.09 - 0.89]) but not major complications. On multivariate cox models, post protocol implementation was associated with improved event free survival (EFS) (HR 0.19 (0.036 - 0.195). Among patients with a diagnosis of hepatoblastoma (n = 62), the occurrence of a major perioperative complication was associated with a worse EFS (HR=5.45, p = 0.03) on multivariate analysis, however this did not translate into an impact on overall survival.

CONCLUSIONS

Our results demonstrate that, for children with primary liver malignancies, a dedication of patients to high-volume surgeons can improve rates of complications of liver resections and may improve the oncological outcome of hepatoblastoma.

Transarterial Radioembolization Treatment as a Bridge to Surgical Resection in Pediatric Hepatocellular Carcinoma

BACKGROUND

Children with unresectable hepatocellular carcinoma (HCC) have a poor prognosis and limited treatment options. Transarterial radioembolization (TARE) using Yttrium-90 (Y90) has emerged as a potential bridge therapy to hepatic resection or transplantation for HCC with very limited studies in children.

OBSERVATIONS

Here we present the clinical course of 2 children successfully treated with TARE Y90 for initially unresectable fibrolamellar HCC (FL-HCC) and bridged to partial hemihepatectomy with >1-year overall survival post-TARE.

CONCLUSION

Although there have been prior published reports of pediatric patients with HCC being treated with TARE Y90 and some being able to undergo subsequent orthotopic liver transplantation, this is the first report of pediatric HCC patients treated with TARE Y90 as a bridge to nontransplant resections and going on to have >1-year overall survival.

Magnetic resonance imaging of primary pediatric liver tumors

Although primary hepatic neoplasms are less common than other intra-abdominal tumors in children, these neoplasms are a significant source of morbidity and mortality in the pediatric population. MRI is increasingly relied upon in the diagnostic evaluation of these lesions, both before and after treatment, and familiarity with the MRI findings associated with these neoplasms is a must for pediatric radiologists. Advances in MRI technology, particularly the advent of hepatocyte-specific gadolinium-based MRI contrast agents, have allowed for accurate characterization of several types of hepatic neoplasms on the basis of imaging appearance. In this review, we provide an overview of the approach to imaging hepatic neoplasms in children using MRI, including a sample imaging protocol. We also discuss the relevant clinical features and MRI findings of the most clinically relevant entities, including their appearance on post-contrast imaging using hepatocyte-specific gadolinium-based MRI contrast agents.

Distinct set of chromosomal aberrations in childhood hepatocellular carcinoma is correlated to hepatitis B virus infection

Hepatocellular carcinoma (HCC) is rarely observed in children and adolescents, but it is reported to be correlated with hepatitis B virus (HBV+) infections. This correlation is not easily explained, because in adults, HBV infections lead to the development of HCC only after decades, not within a few years. In HBV+ adulthood HCC, distinct chromosomal imbalances have been observed. Similar analyses have not been reported for childhood HCC. Here, we investigated whether chromosomal changes were associated with childhood HCC. We analysed formalin-fixed paraffin-embedded (FFPE) samples derived from 17 patients, 0-18 years old, who underwent partial hepatectomies due to HBV+ or HBV- associated HCC. In parallel, in 15 cases, we also analysed non-neoplastic liver tissues adjacent to the HCC. All samples were analysed with high resolution, microarray-based, comparative genomic hybridisation (aCGH). Overall, genomic aberrations in childhood HCC resembled those reported for adulthood HCC. In HBV+ HCC samples, chromosomes 1, 6, 7, 9, 17, 19, and 22 were significantly changed compared to those in HBV- HCC samples. Most interestingly, aberrations for chromosomes 7, 8, 9, 11, and 19 were also observed in corresponding non-neoplastic samples. A specific set of chromosomal abnormalities, including gains in chromosomes 8q, 9q, 11q, and 19, was significantly enriched in HBV+ compared to HBV- non-neoplastic tissues. In childhood HCC, HBV+ was correlated to increased chromosomal instability and specific chromosomal imbalances. A subset of aberrations might be essential in HCC carcinogenesis because they occurred in adjacent, non-neoplastic tissues. In particular, the gain in chromosome 19 appeared to be highly important.

High tricellulin expression is associated with better survival in human hepatoblastoma

AIMS

The more differentiated fetal component of hepatoblastoma (HB) is characterized by increased expression of tight junction (TJ) proteins claudin-1 and -2 when compared with embryonal component. Expression patterns of the recently identified TJ protein tricellulin and the epigenetic regulator enzyme EZH2 were investigated in epithelial subtypes of HB and related to survival.

METHODS AND RESULTS

Twenty-one cases of epithelial HBs subtyped as pure fetal (n = 12) and embryonal/fetal (n = 9), along with 16 non-tumorous samples from surrounding liver, were analysed by immunohistochemistry for tricellulin, β-catenin and EZH2 expression. No significant differences were revealed in overall survival between fetal and embryonal/fetal types of HBs. The fetal component, however, showed considerably increased tricellulin expression while the embryonal component displayed significantly increased nuclear EZH2 positivity, in comparison to other epithelial subtypes and non-tumorous surrounding hepatocytes. Strong nuclear β-catenin staining was notably more frequent in embryonal than in fetal types. High tricellulin expression was associated with significantly increased overall survival (P = 0.03), while elevated EZH2 expression was linked to the presence of distant metastases (P = 0.013).

CONCLUSIONS

Our data indicate that patients with treated HBs showing high expression of tricellulin have significantly better overall survival, independent of histological subtype. Increased nuclear expression of EZH2 was associated with the presence of distant metastases.

Morbidity and mortality associated with liver resections for primary malignancies in children

PURPOSE

Liver resection (LR) is a high-risk procedure with limited data in the pediatric surgical literature regarding short-term outcomes. Our aim was to characterize the patient population and short-term outcomes for children undergoing LR for malignancy.

METHODS

We studied 126 inpatient admissions for children ≤20 years of age undergoing LR in 2009 using the Kids' Inpatient Database. Patients had a principal diagnosis of a primary hepatic malignancy and LR listed as one of the first five procedures. Transplantations were excluded. Complications were defined by ICD-9 codes. High-volume centers performed at least 5 LR.

RESULTS

The mean age was 5.83 years. The morbidity and mortality rates were 30.7 and 3.7%, respectively. The most common causes of morbidity were digestive system complications (7.4%), anemia (7.3%), and respiratory complications (3.8%). 43.9% received a blood product transfusion. The average length of stay was 10.04 days. When compared to low-volume centers, high-volume centers increased the likelihood of a complication fourfold (P = 0.011) but had 0% mortality (P = 0.089).

CONCLUSION

LR remains a procedure fraught with multiple complications and a significant mortality rate. High-volume centers have a fourfold increase in likelihood of complications compared to low-volume centers and may be related to extent of hepatic resection.

MicroRNA expression might predict prognosis of epithelial hepatoblastoma

Hepatoblastoma (HB) is the most common primary liver cancer in childhood. The fetal and mixed embryonal/fetal epithelial subtypes of HB differ not only in grade of differentiation but probably also in prognosis. We aimed to determine microRNA (miRNA) expression patterns of the main subtypes of epithelial HBs to reveal differences and relate them to survival. We studied 20 cases of epithelial HB, subtyped as pure fetal (n = 12) or embryonal/fetal (n = 8). Tissues were sampled according to subtype to arrive at 15 purely fetal and eight purely embryonal samples (n = 8) and 15 samples of non-tumorous surrounding liver (SL). Relative expression of miR-17-5p, miR-18a, miR-21, miR-34a, miR-96, miR-122, miR-181a, miR-195, miR-210, miR-214, miR-221, miR-222, miR-223, and miR-224 was determined by TaqMan MicroRNA Assays applying miR-140 as reference. A higher level of miR-18a (p < 0.01) was found in embryonal samples than in fetal samples. Lower miR-17-5p, miR-195, miR-210, miR-214, and higher miR-221 levels were detected in fetal samples (p < 0.02) in comparison with SL samples, whereas a lower miR-122 level was observed in embryonal samples (p < 0.003). Histological subtype did not correlate with survival; however, high miR-21, low miR-222, and low miR-224 levels proved to be independently prognostic for HB with significantly increased overall survival (p < 0.03). The fetal and embryonal components of epithelial HB, as well as SL, revealed different miRNA expression patterns. Furthermore, miR-21, miR-222, and miR-224 levels predict overall survival of HB patients regardless of epithelial subtype.

A review of 218 pediatric cases of hepatocellular carcinoma

PURPOSE

This study evaluates the incidence trends and clinical outcomes of children with hepatocellular carcinoma (HCC) and assesses factors predictive of patient survival.

METHODS

The Surveillance, Epidemiology, and End Results registry was queried from 1973 to 2009 for all patients between ages 0 and 19 with primary HCC. Demographics, tumor histology, surgical intervention, and patient survival were collected.

RESULTS

Overall, 218 patients were identified. The annual age-adjusted incidence was 0.05 cases per 100,000 in 2009. Fibrolamellar subtype tumors were exclusive to children >5years old and exhibited greater survival compared to non-fibrolamellar subtype (57% vs. 28%, respectively, p=0.002). Tumor extirpation for patients with resectable disease significantly improved overall survival at 5years compared to no surgery (60% vs. 0%, respectively, p<0.0001). Overall 5-, 10- and 20-year survival for the entire cohort was 24%, 23%, and 8%, respectively. Independent prognostic factors of lower mortality according to multivariate analysis were surgical resection (hazard ratio (HR)=0.18), non-Hispanic ethnicity (HR=0.52), and local disease at presentation (HR=0.46).

CONCLUSION

Over the past four decades, the incidence of HCC has remained relatively stable. Children of Hispanic ethnicity have high mortality rates. However, HCC resection for curative intent significantly improves outcomes.