Embryonal sarcoma of the liver in pediatric and young adult patients: A report from Children's Oncology Group study ARST0332.

BACKGROUND: Embryonal sarcoma of the liver (ESL) is a rare mesenchymal tumor most common in childhood; the optimal treatment approach is uncertain. The clinical features and outcomes of patients with ESL enrolled in a Children's Oncology Group (COG) clinical trial that evaluated a risk-based strategy for treating soft tissue sarcomas in patients aged <30 years were evaluated. METHODS: This subset analysis included patients with ESL enrolled in COG study ARST0332. Central review of records, pathology, and imaging confirmed the diagnosis, presenting features, and surgery extent and complications. All patients received dose-intensive ifosfamide/doxorubicin chemotherapy, with cycle timing dependent on surgery and radiotherapy. Tumor resection occurred before study entry or after four cycles of chemotherapy; radiotherapy for residual tumor was optional. RESULTS: Thirty-nine eligible/evaluable patients with ESL were analyzed. All tumors were >10 cm in diameter; four were metastatic. Tumor resection was performed upfront in 23 and delayed in 16. Positive surgical margins (n = 6) and intraoperative tumor rupture (n = 6) occurred only in upfront resections. Eight patients received radiotherapy. Estimated 5-year event-free and overall survival were 79% (95% confidence interval [CI], 65%-93%) and 95% (95% CI, 87%-100%), respectively. Positive margins increased the local recurrence risk. One of 13 patients with documented hemorrhagic ascites and/or tumor rupture developed extrahepatic intra-abdominal tumor recurrence. CONCLUSIONS: The treatment strategy used in ARST0332 achieved favorable outcomes for patients with ESL despite a substantial proportion having high-risk disease features. Deferring tumor resection until after neoadjuvant chemotherapy may decrease the risk of intraoperative tumor rupture and improve the likelihood of adequate surgical margins.

A novel treatment strategy utilizing panobinostat for high-risk and treatment-refractory hepatoblastoma.

BACKGROUND & AIMS: Patients with metastatic, treatment-refractory, and relapsed hepatoblastoma (HB) have survival rates of less than 50% due to limited treatment options. To develop new therapeutic strategies for these patients, our laboratory has developed a preclinical testing pipeline. Given that histone deacetylase (HDAC) inhibition has been proposed for HB, we hypothesized that we could find an effective combination treatment strategy utilizing HDAC inhibition. METHODS: RNA sequencing, microarray, NanoString, and immunohistochemistry data of patient HB samples were analyzed for HDAC class expression. Patient-derived spheroids (PDSp) were used to screen combination chemotherapy with an HDAC inhibitor, panobinostat. Patient-derived xenograft (PDX) mouse models were developed and treated with the combination therapy that showed the highest efficacy in the PDSp drug screen. RESULTS: HDAC RNA and protein expression were elevated in HB tumors compared to normal livers. Panobinostat (IC50 of 0.013-0.059 µM) showed strong in vitro effects and was associated with lower cell viability than other HDAC inhibitors. PDSp demonstrated the highest level of cell death with combination treatment of vincristine/irinotecan/panobinostat (VIP). All four models responded to VIP therapy with a decrease in tumor size compared to placebo. After 6 weeks of treatment, two models demonstrated necrotic cell death, with lower Ki67 expression, decreased serum alpha fetoprotein and reduced tumor burden compared to paired VI- and placebo-treated groups. CONCLUSIONS: Utilizing a preclinical HB pipeline, we demonstrate that panobinostat in combination with VI chemotherapy can induce an effective tumor response in models developed from patients with high-risk, relapsed, and treatment-refractory HB. IMPACT AND IMPLICATIONS: Patients with treatment-refractory hepatoblastoma have limited treatment options with survival rates of less than 50%. Our manuscript demonstrates that combination therapy with vincristine, irinotecan, and panobinostat reduces the size of high-risk, relapsed, and treatment-refractory tumors. With this work we provide preclinical evidence to support utilizing this combination therapy as an arm in future clinical trials.

The impact of congenital heart disease on treatment and survival of patients with hepatoblastoma: A single-center experience.

BACKGROUND: Patients with hepatoblastoma (HB) have a higher risk of congenital heart defects (CHD). There is limited literature on the management and outcomes of these patients. The purpose of this study was to identify demographics and outcomes of these patients in a single tertiary referral center. METHODS: An Institutional Review Board (IRB)-approved retrospective chart review of patients with newly diagnosed HB from October 2004 to January 2021 was performed. CHD was defined as the presence of a septal defect, patent ductus arteriosus, pulmonary atresia, or bicuspid aortic valve. Chi-square and t-test were utilized for statistical analyses. RESULTS: Of the 151 patients diagnosed with HB during the study timeframe, 29 patients were found to have CHD. Five-year overall survival (OS) for non-CHD HB patients was 81.9% compared to 68.9% in the CHD cohort (p = .12). The 5-year OS for patients without surgically intervened CHD was 63.6% compared to 70.5% for those with surgically repaired CHD (p = .88). Pre-treatment extent of tumor IV was present more often in patients with HB and CHD who passed away (6/9, 66.7%) compared to those who survived (3/16,18.8%, p = .01). CONCLUSIONS: Patients with HB and CHD have similar survival compared to those without CHD. Our data support that patients with HB and CHD should be treated with curative intent including cardiac surgical intervention, medical oncology therapy, and oncological surgery for their 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.

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.

Histologic type predicts disparate outcomes in pediatric hepatocellular neoplasms: A Pediatric Surgical Oncology Research Collaborative study.

BACKGROUND: Hepatocellular carcinoma (HCC) is a rare cancer in children, with various histologic subtypes and a paucity of data to guide clinical management and predict prognosis. METHODS: A multi-institutional review of children with hepatocellular neoplasms was performed, including demographic, staging, treatment, and outcomes data. Patients were categorized as having conventional HCC (cHCC) with or without underlying liver disease, fibrolamellar carcinoma (FLC), and hepatoblastoma with HCC features (HB-HCC). Univariate and multivariate analyses identified predictors of mortality and relapse. RESULTS: In total, 262 children were identified; and an institutional histologic review revealed 110 cHCCs (42%; 69 normal background liver, 34 inflammatory/cirrhotic, 7 unknown), 119 FLCs (45%), and 33 HB-HCCs (12%). The authors observed notable differences in presentation and behavior among tumor subtypes, including increased lymph node involvement in FLC and higher stage in cHCC. Factors associated with mortality included cHCC (hazard ratio [HR], 1.63; P = .038), elevated α-fetoprotein (HR, 3.1; P = .014), multifocality (HR, 2.4; P < .001), and PRETEXT (pretreatment extent of disease) stage IV (HR, 5.76; P < .001). Multivariate analysis identified increased mortality in cHCC versus FLC (HR, 2.2; P = .004) and in unresectable tumors (HR, 3.4; P < .001). Disease-free status at any point predicted survival. CONCLUSIONS: This multi-institutional, detailed data set allowed a comprehensive analysis of outcomes for children with these rare hepatocellular neoplasms. The current data demonstrated that pediatric HCC subtypes are not equivalent entities because FLC and cHCC have distinct anatomic patterns and outcomes in concert with their known molecular differences. This data set will be further used to elucidate the impact of histology on specific treatment responses, with the goal of designing risk-stratified algorithms for children with HCC. LAY SUMMARY: This is the largest reported granular data set on children with hepatocellular carcinoma. The study evaluates different subtypes of hepatocellular carcinoma and identifies key differences between subtypes. This information is pivotal in improving understanding of these rare cancers and may be used to improve clinical management and subsequent outcome in children with these rare malignancies.

Hepatoblastomas with carcinoma features represent a biological spectrum of aggressive neoplasms in children and young adults.

BACKGROUND & AIMS: Hepatoblastoma (HB) and hepatocellular carcinoma (HCC) are the predominant liver cancers in children, though their respective treatment options and associated outcomes differ dramatically. Risk stratification using a combination of clinical, histological, and molecular parameters can improve treatment selection, but it is particularly challenging for tumors with mixed histological features, including those in the recently created hepatocellular neoplasm not otherwise specified (HCN NOS) provisional category. We aimed to perform the first molecular characterization of clinically annotated cases of HCN NOS. METHODS: We tested whether these histological features are associated with genetic alterations, cancer gene dysregulation, and outcomes. Namely, we compared the molecular features of HCN NOS, including copy number alterations, mutations, and gene expression profiles, with those in other pediatric hepatocellular neoplasms, including HBs and HCCs, as well as HBs demonstrating focal atypia or pleomorphism (HB FPAs), and HBs diagnosed in older children (>8). RESULTS: Molecular profiles of HCN NOS and HB FPAs revealed common underlying biological features that were previously observed in HCCs. Consequently, we designated these tumor types collectively as HBs with HCC features (HBCs). These tumors were associated with high mutation rates (∼3 somatic mutations/Mb) and were enriched with mutations and alterations in key cancer genes and pathways. In addition, recurrent large-scale chromosomal gains, including gains of chromosomal arms 2q (80%), 6p (70%), and 20p (70%), were observed. Overall, HBCs were associated with poor clinical outcomes. CONCLUSIONS: Our study indicates that histological features seen in HBCs are associated with combined molecular features of HB and HCC, that HBCs are associated with poor outcomes irrespective of patient age, and that transplanted patients are more likely to have good outcomes than those treated with chemotherapy and surgery alone. These findings highlight the importance of molecular testing and early therapeutic intervention for aggressive childhood hepatocellular neoplasms. LAY SUMMARY: We molecularly characterized a class of histologically aggressive childhood liver cancers and showed that these tumors are clinically aggressive and that their observed histological features are associated with underlying recurrent molecular features. We proposed a diagnostic algorithm to identify these cancers using a combination of histological and molecular features, and our analysis suggested that these cancers may benefit from specialized treatment strategies that may differ from treatment guidelines for other childhood liver cancers.

Angiosarcoma of the Pancreas in a Pediatric Patient With an Activating KDR-Internal Tandem Duplication: A Case Report and Review of the Literature.

Pancreatic angiosarcoma is an exceedingly rare malignancy accounting for <1% of pancreatic neoplasms. A very limited number of pancreatic angiosarcomas have been reported in the literature without any cases described in children. We present the case of a 17-year-old female diagnosed with angiosarcoma of the pancreas following pancreaticoduodenectomy for a pancreatic mass, initially presumed to be a solid pseudopapillary neoplasm of the pancreas. The angiosarcoma was found to have a novel activating internal tandem duplication in the KDR gene (KDR-internal tandem duplication). We discuss the current literature on this disease process. This is the first reported case of pancreatic angiosarcoma in a pediatric patient and the first with an activating KDR-internal tandem duplication.

Seroconversion and side effects after COVID vaccination among persons with type 2 diabetes in urban, rural, and tribal areas in Kerala, India.

Background: Persons with type 2 diabetes mellitus (T2DM) are at high-risk for COVID-19 infection and are a priority group for vaccination. Objectives: The objective of this study is to estimate the seroconversion and determine the side effects after COVID-19 vaccination among persons with T2DM in urban, rural, and tribal areas in Kerala. Methods: A cross-sectional study was conducted in urban, rural, and tribal field practice areas of a medical college in Central Kerala, among 396 persons with T2DM. The participants were selected by simple random sampling from the 200-250 diabetic patients visiting each health center. Qualitative and quantitative estimation of antibodies were done by WANTAI Ab enzyme-linked immunosorbent assay kit and Abbott SARS COV-2 IgG Quantitative assay, respectively. Results: The mean age of the respondents was 59.40 ± 12.25 years. A majority (65.5%) had received both doses of vaccine. About half (51.5%) experienced side effects after vaccination. Antibodies (IgG or IgM) were detected in 93.2% (95% confidence interval [CI] 90.2, 95.5) of participants. Those with a duration of diabetes ≥5 years, with a single dose of vaccine, were five times (adjusted odds ratio [aOR] - 5.23,95% CI 1.86, 14.66) and four times (aOR - 4.11, 95% CI 1.66, 10.13) more likely, respectively, to be seronegative. Those who took medication for diabetes were protected against a no antibody (aOR - 0.05, 95% CI 0.02, 0.148) response. The median antibody titer in a subset (150) of participants was 365.2 (90-1587) AU/ml. Past COVID infection was an independent determinant of high IgG titers (aOR - 4.95, 95% CI 1.50, 16.36). Conclusion: Reinforcing the importance of vaccination particularly among those with longer duration of diabetes is imperative.

Thoracoscopy vs thoracotomy for the management of metastatic osteosarcoma: A Pediatric Surgical Oncology Research Collaborative Study.

Complete surgical resection of pulmonary metastatic disease in patients with osteosarcoma is crucial to long-term survival. Open thoracotomy allows palpation of nodules not identified on imaging but the impact on survival is unknown. The objective of this study was to compare overall survival (OS) and pulmonary disease-free survival (DFS) in children who underwent thoracotomy vs thoracoscopic surgery for pulmonary metastasectomy. A multi-institutional collaborative group retrospectively reviewed 202 pediatric patients with osteosarcoma who underwent pulmonary metastasectomy by thoracotomy (n = 154) or thoracoscopy (n = 48). Results were analyzed by Kaplan-Meier survival estimates and multivariate Cox proportional hazard regression models. With median follow-up of 45 months, 135 (67.5%) patients had a pulmonary relapse and 95 (47%) patients were deceased. Kaplan-Meier analysis showed no significant difference in 5-year pulmonary DFS (25% vs 38%; P = .18) or OS (49% vs 42%, P = .37) between the surgical approaches of thoracotomy and thoracoscopy. In Cox regression analysis controlling for other factors impacting outcome, there was a significantly increased risk of mortality (HR 2.11; P = .027; 95% CI 1.09-4.09) but not pulmonary recurrence (HR 0.96; P = .90; 95% CI 0.52-1.79) with a thoracoscopic approach. However, in the subset analysis limited to patients with oligometastatic disease, thoracoscopy had no increased risk of mortality (HR 1.16; P = .62; 0.64-2.11). In conclusion, patients with metastatic osteosarcoma and limited pulmonary disease burden demonstrate comparable outcomes after thoracotomy and thoracoscopy for metastasectomy. While significant selection bias in these surgical cohorts limits the generalizability of the conclusions, clinical equipoise for a randomized clinical trial in patients with oligometastatic disease is supported.

Pneumonectomy for Pediatric Tumors-a Pediatric Surgical Oncology Research Collaborative Study.

OBJECTIVE: To describe utilization and long-term outcomes of pneumonectomy in children and adolescents with cancer. SUMMARY BACKGROUND DATA: Pneumonectomy in adults is associated with significant morbidity and mortality. Little is known about the indications and outcomes of pneumonectomy for pediatric tumors. METHODS: The Pediatric Surgical Oncology Research Collaborative (PSORC) identified pediatric patients <21 years of age who underwent pneumonectomy from 1990 to 2017 for primary or metastatic tumors at 12 institutions. Clinical information was collected; outcomes included operative complications, long-term function, recurrence, and survival. Univariate log rank, and multivariable Cox analyses determined factors associated with survival. RESULTS: Thirty-eight patients (mean 12 ±â€Š6 yrs) were identified; median (IQR) follow-up was 19 (5-38) months. Twenty-six patients (68%) underwent pneumonectomy for primary tumors and 12 (32%) for metastases. The most frequent histologies were osteosarcoma (n = 6), inflammatory myofibroblastic tumors (IMT; n = 6), and pleuropulmonary blastoma (n = 5). Median postoperative ventilator days were 0 (0-1), intensive care 2 (1-3), and hospital 8 (5-16). Early postoperative complications occurred in 10 patients including 1 death. Of 25 (66%) patients alive at 1 year, 15 reported return to preoperative pulmonary status. All IMT patients survived while all osteosarcoma patients died during follow-up. On multivariable analysis, metastatic indications were associated with nonsurvival (HR = 3.37, P = 0.045). CONCLUSION: This is the largest review of children who underwent pneumonectomy for cancer. There is decreased procedure-related morbidity and mortality than reported for adults. Survival is worse with preoperative metastatic disease, especially osteosarcoma.

Sclerosing Encapsulating Peritonitis in a Pediatric Patient Treated With Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy.

BACKGROUND: Sclerosing encapsulating peritonitis (SEP) is a rare chronic inflammatory condition characterized by small bowel encapsulation by a thick fibrocollagenous membrane. Patients with SEP often present with nonspecific symptoms, such as abdominal pain and distension, however some patients may present with symptoms suggestive of intestinal obstruction. Secondary SEP has been reported in patients undergoing peritoneal dialysis and has been recently described in adults following cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). OBSERVATIONS: We report a clinical case of a 13-year-old female who presented with worsening abdominal pain and distension and persistent emesis who was found to have SEP 13 months following CRS and HIPEC for management of desmoplastic small round cell tumor and subsequently required operative intervention. CONCLUSION: Although there have been published reports of adult patients experiencing cases of SEP following CRS/HIPEC, this is the first published case of secondary SEP occurring in a pediatric oncology patient.

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.

A Traumatic Quinceañera: Acute Superior Mesenteric Artery Syndrome in an Adolescent Girl.

ABSTRACT: A 15-year-old girl presented with 3 days of progressive abdominal distention, pain, and bilious hematemesis. Her symptoms began after her quinceañera, during which she wore a tight corset. On examination, she was thin and had significant abdominal distention and pain. A computed tomography revealed a massively dilated stomach and proximal duodenum to the region of the superior mesenteric artery (SMA) with distal decompression. An upper gastrointestinal fluoroscopy demonstrated marked dilation of the stomach through the mid third portion of the duodenum with distal decompression and an associated linear compression on her duodenal wall. We believe that she developed acute SMA syndrome. Superior mesenteric artery syndrome is a partial bowel obstruction caused when the third portion of the duodenum is compressed as it passes between the SMA and the aorta. Although the SMA syndrome is most commonly described as a condition associated with chronic, severe weight loss resulting in a narrowing of the SMA to aorta angle and subsequent duodenal compression, it can present acutely from causes such as a postoperative complication, blunt trauma, or external compression. Previously described acute SMA syndrome from external compression has been the result of medically necessary causes, such as body casting. In this case, the tight gown was likely the inciting factor for her development of SMA syndrome; however, she was placed at high risk for the condition by being underweight at baseline and experiencing food restriction for several days preceding her quinceañera. She was treated conservatively with nasogastric decompression and parenteral nutrition, and has since completely recovered.

Optimization of percutaneous biopsy for diagnosis and pretreatment risk assessment of neuroblastoma.

BACKGROUND: Image-guided percutaneous core needle biopsy (PCNB) is increasingly utilized to diagnose solid tumors. The objective of this study is to determine whether PCNB is adequate for modern biologic characterization of neuroblastoma. PROCEDURE: A multi-institutional retrospective study was performed by the Pediatric Surgical Oncology Research Collaborative on children with neuroblastoma at 12 institutions over a 3-year period. Data collected included demographics, clinical details, biopsy technique, complications, and adequacy of biopsies for cytogenetic markers utilized by the Children's Oncology Group for risk stratification. RESULTS: A total of 243 children were identified with a diagnosis of neuroblastoma: 79 (32.5%) tumor excision at diagnosis, 94 (38.7%) open incisional biopsy (IB), and 70 (28.8%) PCNB. Compared to IB, there was no significant difference in ability to accurately obtain a primary diagnosis by PCNB (95.7% vs 98.9%, P = .314) or determine MYCN copy number (92.4% vs 97.8%, P = .111). The yield for loss of heterozygosity and tumor ploidy was lower with PCNB versus IB (56.1% vs 90.9%, P < .05; and 58.0% vs. 88.5%, P < .05). Complications did not differ between groups (2.9 % vs 3.3%, P = 1.000), though the PCNB group had fewer blood transfusions and lower opioid usage. Efficacy of PCNB was improved for loss of heterozygosity when a pediatric pathologist evaluated the fresh specimen for adequacy. CONCLUSIONS: PCNB is a less invasive alternative to open biopsy for primary diagnosis and MYCN oncogene status in patients with neuroblastoma. Our data suggest that PCNB could be optimized for complete genetic analysis by standardized protocols and real-time pathology assessment of specimen quality.

Pancreaticoduodenectomy for the treatment of pancreatic neoplasms in children: A Pediatric Surgical Oncology Research Collaborative study.

BACKGROUND: To better characterize short-term and long-term outcomes in children with pancreatic tumors treated with pancreaticoduodenectomy (PD). METHODS: Patients 21 years of age or younger who underwent PD at Pediatric Surgical Oncology Collaborative (PSORC) hospitals between 1990 and 2017 were identified. Demographic, clinical information, and outcomes (operative complications, long-term pancreatic function, recurrence, and survival) were collected. RESULTS: Sixty-five patients from 18 institutions with a median age of 13 years (4 months-22 years) and a median (IQR) follow-up of 2.8 (4.3) years were analyzed. Solid pseudopapillary tumor of the pancreas (SPN) was the most common histology. Postoperative complications included pancreatic leak in 14% (n = 9), delayed gastric emptying in 9% (n = 6), marginal ulcer in one patient, and perioperative (30-day) death due to hepatic failure in one patient. Pancreatic insufficiency was observed in 32% (n = 21) of patients, with 23%, 3%, and 6% with exocrine, or endocrine insufficiencies, or both, respectively. Children with SPN and benign neoplasms all survived. Overall, there were 14 (22%) recurrences and 11 deaths (17%). Univariate analysis revealed non-SPN malignant tumor diagnosis, preoperative vascular involvement, intraoperative transfusion requirement, pathologic vascular invasion, positive margins, and need for neoadjuvant chemotherapy as risk factors for recurrence and poor survival. Multivariate analysis only revealed pathologic vascular invasion as a risk factor for recurrence and poor survival. CONCLUSION: This is the largest series of pediatric PD patients. PD is curative for SPN and benign neoplasms. Pancreatic insufficiency is the most common postoperative complication. Outcome is primarily associated with histology.

Congenital spindle cell rhabdomyosarcoma.

Spindle cell and sclerosing rhabdomyosarcoma (ssRMS) is a rare variant of rhabdomyosarcoma, which includes three distinct subtypes. In infants, these tumors are commonly associated with recurring fusions involving VGLL2 or NCOA2 and have a favorable prognosis. We present four cases of ssRMS and 16 additional cases from the literature, which show that these patients present with localized disease and have an excellent prognosis regardless of surgical margin or lack of radiation therapy. Molecularly defined spindle cell rhabdomyosarcoma in infants is likely a biologically distinct entity which may not require the aggressive multimodal treatment used for other subtypes of rhabdomyosarcoma.

Characterization of pediatric hepatocellular carcinoma reveals genomic heterogeneity and diverse signaling pathway activation.

BACKGROUND: Pediatric hepatocellular carcinoma (HCC) is a rare liver tumor in children with a poor prognosis. Comprehensive molecular profiling to understand the underlying genomic drivers of this tumor has not been completed, and it is unclear whether nonfibrolamellar pediatric HCC is more genomically similar to hepatoblastoma or adult HCC. PROCEDURE: To characterize the molecular landscape of these tumors, we analyzed a cohort of 15 pediatric non-FL-HCCs by sequencing a panel of cancer-associated genes and conducting copy-number and gene-expression analyses. RESULTS: We detected multiple types of molecular alterations in Wnt signaling genes, including APC inversion, AMER1 somatic mutation, and most commonly CTNNB1 intragenic deletions. There were multiple alterations to the telomerase pathway via TERT activation or ATRX mutation. Therapeutically targetable activating mutations in MAPK/ERK signaling pathway genes, including MAPK1 and BRAF, were detected in 20% of tumors. TP53 mutations occurred far less frequently in our pediatric HCC cohort than reported in adult cohorts. Tumors arising in children with underlying liver disease were found to be molecularly distinct from the remainder and lacking detectable oncogenic drivers, as compared with those arising in patients without a history of underlying liver disease; the majority of both types were positive for glypican-3, another potential therapeutic target. CONCLUSION: Our study revealed pediatric HCC to be a molecularly heterogeneous group of tumors. Those non-FL-HCC tumors arising in the absence of underlying liver disease harbor genetic alterations affecting multiple cancer pathways, most notably Wnt signaling, and share some characteristics with adult HCC.

Generation of patient-derived tumor xenografts from percutaneous tumor biopsies in children with bone sarcomas.

One of the limitations of performing percutaneous biopsies in patients with bone sarcomas is the small amount of tumor that can be obtained for research purposes. Here, we describe our experience developing patient-derived tumor xenografts (PDXs) using percutaneous tumor biopsies in children with bone sarcomas. We generated 14 bone sarcoma PDXs from percutaneous tumor biopsies. We also developed eight bone sarcoma PDXs from surgical resection of primary bone tumors and pulmonary metastases. A multidisciplinary team approach was critical to establish an accurate diagnosis and to provide adequate tumor samples for PDX generation.

Socioeconomic disparities affect survival in malignant ovarian germ cell tumors in AYA population.

BACKGROUND: Malignant ovarian germ cell tumors (MOGCTs) are a rare form of ovarian malignancy. Socioeconomic status (SES) has been shown to affect survival in several gynecologic cancers. We examined whether SES impacted survival in adolescent and young adults (AYAs) with MOGCT. MATERIALS AND METHODS: The National Cancer Data Base was used to identify AYAs (aged 15-39 years) with MOGCT from 1998 to 2012. Three SES surrogate variables identified were as follows: insurance type, income quartile, and education quartile. Pooled variance t-tests and chi-square tests were used to compare tumor characteristics, the time from diagnosis to staging/treatment, and clinical outcome variables for each SES surrogate variable, while controlling for age and race/ethnicity in a multivariate model. Kaplan-Meier survival estimates were calculated using the log-rank test. RESULTS: A total of 3125 AYAs with MOGCT were identified. Subjects with lower SES measures had higher overall stage and T-stage MOGCTs at presentation. There was no significant difference in the time to staging/treatment, extent of surgery, or use of chemotherapy by SES. Subjects from a lower education background, from a lower income quartile, and without insurance had decreased survival (P ≤ 0.02 for all). Controlling for overall stage and T-stage, the difference in survival was no longer significant. CONCLUSIONS: AYAs with MOGCT from lower SES backgrounds presented with more advanced stage disease. Further studies that focus on the underlying reasons for this difference are needed to address these disparities.