A Pediatric Primary Cardiac Spindle Cell Neoplasm With a Rare PDGFRA::USP8 Gene Fusion: A Case Report.

We report a case of a primary cardiac spindle cell neoplasm with concerning histological features and a rare PDGFRA::USP8 gene fusion in a 3 year old boy. The patient presented with a large cardiac mass predominantly in the right ventricle, originating from the ventricular septum. The mass was resected with grossly negative margins. Pathology revealed an unclassified spindle cell neoplasm with a PDGFRA::USP8 gene fusion. This gene fusion has only been previously reported twice in the medical literature, one in a pediatric cardiac sarcoma and the other in an abdominal soft tissue tumor in an adult woman. The patient is alive and well with no evidence of recurrence 11 months after excision.

Characterizing Lymphovascular Invasion in Pediatric and Adolescent Malignant Ovarian Nongerminomatous Germ Cell Tumors: A Report from the Children's Oncology Group.

BACKGROUND: Lymphovascular invasion (LVI) has been identified as a poor prognostic factor for a variety of tumors; however, its significance in malignant ovarian germ cell tumors (MOGCT) in pediatric and adolescent patients is not well described. We aim to clarify the significance of LVI in the subset of patients with nongerminomatous MOGCT. METHODS: Records of patients 0-20 years of age with MOGCT enrolled on Children's Oncology Group study AGCT0132 were reviewed. Patients with documented presence or absence of LVI in either institutional or central review pathology reports were included. RESULTS: Of 130 patients with MOGCTs, 83 patients had of the presence or absence of LVI documented in their pathology report. 42/83 patients (50.6%) were found to have LVI present. The estimated odds of having LVI was higher in patients with stage II and III disease, 11 years and older and with the presence of choriocarcinoma. Event-free survival (EFS) and overall survival (OS) remained high in patients with LVI. Approximately 50% of patients with a documented LVI status in either institutional pathology report or central review were found to have LVI. CONCLUSIONS: The presence of LVI was higher in tumors with adverse risk factors including higher stage and age greater than 11 years. While LVI was not associated with EFS or OS in the intermediate risk group, further work is necessary to determine the effect of LVI on long-term disease-free survival. We, therefore, recommend routinely incorporating LVI status into institutional pathology reports for pediatric and adolescent patients with MOGCT. LEVEL OF EVIDENCE: III.

Children's Oncology Group's 2023 blueprint for research: Germ cell tumors.

Extracranial germ cell tumors (GCT) are a biologically diverse group of tumors occurring in children, adolescents, and young adults. The majority of patients have excellent outcomes, but treatment-related toxicities impact their quality of survivorship. A subset of patients succumbs to the disease. Current unmet needs include clarifying which patients can be safely observed after initial surgical resection, refinement of risk stratification to reduce chemotherapy burden in patients with standard-risk disease, and intensify therapy for patients with poor-risk disease. Furthermore, enhancing strategies for detection of minimal residual disease and early detection of relapse, particularly in serum tumor marker-negative histologies, is critical. Improving the understanding of the developmental and molecular origins of GCTs may facilitate discovery of novel targets. Future efforts should be directed toward assessing novel therapies in a biology-driven, biomarker-defined, histology-specific, risk-stratified patient population. Fragmentation of care between subspecialists restricts the unified study of these rare tumors. It is imperative that trials be conducted in collaboration with national and international cooperative groups, with harmonized data and biospecimen collection. Key priorities for the Children's Oncology Group (COG) GCT Committee include (a) better understanding the biology of GCTs, with a focus on molecular targets and mechanisms of treatment resistance; (b) strategic development of pediatric and young adult clinical trials; (c) understanding late effects of therapy and identifying individuals most at risk; and (d) prioritizing diversity, equity, and inclusion to reduce cancer health disparities and studying the impacts of social determinants of health on outcomes.

Integrated genomic analysis reveals aberrations in WNT signaling in germ cell tumors of childhood and adolescence.

Germ cell tumors (GCTs) are neoplasms of the testis, ovary and extragonadal sites that occur in infants, children, adolescents and adults. Post-pubertal (type II) malignant GCTs may present as seminoma, non-seminoma or mixed histologies. In contrast, pre-pubertal (type I) GCTs are limited to (benign) teratoma and (malignant) yolk sac tumor (YST). Epidemiologic and molecular data have shown that pre- and post-pubertal GCTs arise by distinct mechanisms. Dedicated studies of the genomic landscape of type I and II GCT in children and adolescents are lacking. Here we present an integrated genomic analysis of extracranial GCTs across the age spectrum from 0-24 years. Activation of the WNT pathway by somatic mutation, copy-number alteration, and differential promoter methylation is a prominent feature of GCTs in children, adolescents and young adults, and is associated with poor clinical outcomes. Significantly, we find that small molecule WNT inhibitors can suppress GCT cells both in vitro and in vivo. These results highlight the importance of WNT pathway signaling in GCTs across all ages and provide a foundation for future efforts to develop targeted therapies for these cancers.

A Malignant Hepatoblastoma Mimicking a Benign Mesenchymal Hamartoma: Lessons Learned.

Differentiating hepatoblastomas from other congenital benign hepatic tumors is key to surgical management. We, herein, present an unusual case of an antenatally diagnosed liver lesion assessed in the neonatal period. Because of its predominantly cystic ultrasound/MRI appearance and borderline alpha-fetoprotein serum levels the diagnosis of mesenchymal hamartoma was favored and protocol-based tumor resection was performed. Due to the intraoperative diagnosis of a fetal subtype of hepatoblastoma with positive resection margins the child had to undergo a second laparotomy. This report raises awareness to an unusual appearance of hepatoblastoma and discusses noninvasive imaging clues to consider atypical appearances of hepatoblastoma preoperatively as they can have profound implications in patient management.

A typical anterior retinoblastoma: diagnosis by aqueous humor cell-free DNA analysis.

BACKGROUND: Aqueous humor from eyes with active retinoblastoma contains tumor-derived cell-free DNA. MATERIALS AND METHODS: Single retrospective case report. RESULTS: A 13-year-old girl with acute right eye pain and redness was diagnosed with hypertensive anterior uveitis. Following initial management, she was referred to ocular oncology for an atypical clinical picture. Multiple seeds were noted 360 degrees in the anterior chamber, at the equator of the lens and canal of Petit, and ultrasound biomicroscopy identified a temporal pars plana lesion. While aqueous humor cytology was inconclusive for malignancy, targeted next-generation sequencing of aqueous cell-free DNA identified biallelic RB1 full gene deletion, confirming the diagnosis of retinoblastoma. Partial regression followed three cycles of systemic carboplatin, etoposide, and vincristine and three intracameral melphalan injections. Four months later, she had recurrence of the primary tumor and increase in seeding and received the investigational sustained release episcleral topotecan chemoplaque. Stable regression was achieved to 28-month follow-up, with no detectable aqueous cell-free DNA. CONCLUSIONS: RB1 sequencing analysis of tumor-derived cell-free DNA from aqueous humor can confirm the diagnosis of retinoblastoma in cases of diagnostic uncertainty.

Clinicopathologic predictors of outcomes in children with stage I testicular germ cell tumors: A pooled post hoc analysis of trials from the Children's Oncology Group.

BACKGROUND: Patients with clinical stage I (CS I: cN0M0) testicular germ cell tumors (TGCT) exhibit favorable oncologic outcomes. While prognostic features can help inform treatment in adults with CS I TGCT, we lack reliable means to predict relapse among pediatric and adolescent patients. OBJECTIVE: We sought to identify predictors of relapse in children with CS I TGCT. STUDY DESIGN: We performed a pooled post hoc analysis on pediatric and adolescent AJCC CS I TGCT patients enrolled in 3 prospective trials: INT-0097 (phase II), INT-0106 (phase III), and AGCT0132 (phase III). Pathology was centrally reviewed. Patient demographics, pT stage, serum tumor markers, margin status, histology, relapse, and survival were compiled. Cox regression analyses were used to identify predictors of events, defined as relapse, secondary malignant neoplasm, or death. RESULTS: 106 patients were identified with outcomes data available. Most patients were pT1-2 stage. Among patients with evaluable histopathology, yolk sac tumor elements were present in all patients and lymphovascular invasion in 51% of patients. Over a median follow-up of 56 months, no patients died, and 25 patients (24%) experienced an event (median event-free survival not reached). Independent predictors of events on multivariable analysis included age ≥12 years at diagnosis (HR 8.87, p < 0.001) and higher pT stage (pT2 HR 7.31, p = 0.0017; pT3 HR 13.5, p = 0.0043). DISCUSSION: Although our study population reflects the largest pooled prospective cohort of CS I pediatric and adolescent TGCT to our knowledge, the relatively low event rate limits our multivariable analysis, and longer follow-up duration would help further characterize the natural history of these patients. Centralized pathologic review was also unable to be performed for several patients. CONCLUSION: Pediatric and adolescent CS I TGCT patients exhibit remarkable 5-year survival. Using combined data from multiple prospective trials, our study identifies clinicopathologic features that predict relapse and inform personalized treatment for these patients by potentially guiding surveillance versus adjuvant treatment strategies.

Asynchronous pineoblastoma is more likely after early diagnosis of retinoblastoma: a meta-analysis.

PURPOSE: To determine the risk of patients with an early diagnosis of heritable retinoblastoma being diagnosed with TRb (or pineoblastoma) asynchronously in a later stage and its effect on screening. METHODS: We updated the search (PubMed and Embase) for published literature as performed by our research group in 2014 and 2019. Trilateral retinoblastoma (TRb) patients were eligible for inclusion if identifiable as unique and the age at which TRb was diagnosed was available. The search yielded 97 new studies. Three new studies and eight new patients were included. Combined with 189 patients from the previous meta-analysis, the database included 197 patients. The main outcome was the percentage of asynchronous TRb in patients diagnosed before and after preset age thresholds of 6 and 12 months of age at retinoblastoma diagnosis. RESULTS: Seventy-nine per cent of patients with pineoblastoma are diagnosed with retinoblastoma before the age of 12 months. However, baseline MRI screening at time of retinoblastoma diagnosis fails to detect the later diagnosed pineal TRb in 89% of patients. We modelled that an additional MRI performed at the age of 29 months picks up 53% of pineoblastomas in an asymptomatic phase. The detection rate increased to 72%, 87% and 92%, respectively, with 2, 3 and 4 additional MRIs. CONCLUSIONS: An MRI of the brain in heritable retinoblastoma before the age of 12 months misses most pineoblastomas, while retinoblastomas are diagnosed most often before the age of 12 months. Optimally timed additional MRI scans of the brain can increase the asymptomatic detection rate of pineoblastoma.

Clinical audit of retinoblastoma management: a retrospective single-institution study.

OBJECTIVE: The primary aim of this study was to identify the frequency of death, metastasis, enucleation, and use of external beam radiation therapy (EBRT) among retinoblastoma patients. The secondary aim was to determine whether any events were associated with suboptimal clinical management to identify areas for clinical care improvement. METHODS: Patients diagnosed with retinoblastoma between January 1, 2000, and December 31, 2015, at The Hospital for Sick Children were included. Medical records of eligible patients underwent a comprehensive 2-part review. First, a chart review collected diagnostic details, treatment course, and occurrence of 4 events: death, metastasis, use of EBRT, and enucleation. Next, events were reviewed in detail, and a multidisciplinary committee reached consensus on cases managed suboptimally. RESULTS: The study included 209 patients (292 eyes). There were 8 deaths, 11 metastases, 177 enucleations (143 primary, 34 secondary), and 8 uses of EBRT. Thirteen patients were reviewed by the multidisciplinary committee, which confirmed that 5 of these patients had events associated with suboptimal clinical management. Three patients developed metastases leading to death (misdiagnosis and mismanagement of trilateral retinoblastoma [1], parental refusal of enucleation [1], and inaccurate histopathology after primary enucleation [1]). One patient developed extraocular extension related to scleral invasion following aggressive focal therapy. One patient underwent secondary enucleation for a Group B eye related to mismanagement of a treatment complication. DISCUSSION: Deaths, metastases, and enucleations with documented instances of suboptimal care highlighted a need to enhance medical team and patient communication, histopathology interpretation, laser treatment guidelines, and trilateral retinoblastoma management. Routine clinical audit of retinoblastoma management can identify areas for clinical practice change.

Imaging and clinical features of pediatric hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is rare in children and there is limited data on its imaging features. OBJECTIVE: To describe imaging features of pediatric HCC and correlate them with clinical and laboratory findings. MATERIALS AND METHODS: We retrospectively reviewed imaging in all pediatric HCC cases seen between January 2000 and January 2019. Imaging features defined in LI-RADS (Liver Imaging Reporting and Data System) and tumor extent by PRETEXT (pretreatment extent of disease) criteria were noted by two radiologists. Patient charts were reviewed to collect clinical features, alpha-fetoprotein (AFP) level and pathology findings. RESULTS: Of the 15 children (7 boys, 8 girls; mean age: 11.8 years, age range: 6-17 years) included in the study, 12/15 had computed tomography, 9/15 had magnetic resonance imaging and 9/15 had ultrasound exams available for review. Pathological types of HCC included classic (11/15, 73%), fibrolamellar (3/15, 20%) and mixed cholangiocarcinoma-HCC (1/15, 7%). Eighty percent occurred de novo in normal liver and 67% showed elevated AFP levels. Arterial phase hyperenhancement was seen in 83% of cases, washout in 86%, capsule in 50% and tumor-in-vein in 33%. The mean tumor size was 9.8 cm and 40% were multifocal on imaging. Staging revealed PRETEXT II tumors in 47%, III in 20% and IV in 33%. There were no PRETEXT I tumors. The two most common PRETEXT annotation factors were portal vein and caudate lobe involvement in 71% and 43% of cases, respectively. Fibrolamellar HCC demonstrated central scar, normal AFP levels and normal background liver. CONCLUSION: Pediatric HCC are large heterogeneous tumors, as reflected by high PRETEXT staging, and commonly include portal vein and caudate involvement. This affects resectability of these tumors at presentation. Central scar, normal AFP level and normal liver background may help differentiate fibrolamellar HCC from other types of HCC.

Feasibility of ultrasound-assisted lumbar punctures performed by pediatric oncologists at the point of care.

BACKGROUND: Ultrasound assistance improves success rates and reduces adverse outcomes of lumbar punctures (LPs) among adult patients in the emergency room and the operating room, but has not been evaluated in pediatric patients with cancer. Our objectives were (1) to determine whether pediatric oncologists could perform ultrasound-assisted LPs following a structured teaching curriculum, and (2) to determine the feasibility of recruiting pediatric cancer patients to a clinical trial of this procedure. METHODS: Three pediatric oncologists completed a curriculum composed of didactic teaching followed by hands-on workshops. Each learner was evaluated during 20 attempts at three ultrasound tasks using the cumulative sum method. The three pediatric oncologists then performed ultrasound assessments prior to routinely scheduled LPs. Feasibility was defined as ability to perform at least 30 ultrasound-assisted LPs within 6 months. Secondary outcomes were the proportion of successful, bloody, or traumatic LPs, time required, and perceived helpfulness of ultrasound. RESULTS: All three pediatric oncologists achieved competence in the three tasks of ultrasound scanning within 20 evaluated attempts. We recruited 62 patients within 1 month, and 58 underwent an ultrasound-assisted LP. All LPs were successful. Two LPs (4%) had ≥500 red blood cells (RBCs)/µl, and nine (16%) had ≥10 RBCs/µl. Median time to conduct the scan was 1.9 minutes (range 0.8-4.0 minutes). In 37 (64%) of the LPs, ultrasound assistance was considered helpful or very helpful. CONCLUSIONS: Pediatric oncologists readily achieved competence in ultrasound-assisted LPs, and ultrasound was commonly perceived as helpful. It is feasible to proceed to a randomized trial of this procedure in pediatric cancer.

Outcomes of adolescent males with extracranial metastatic germ cell tumors: A report from the Malignant Germ Cell Tumor International Consortium.

BACKGROUND: Adolescents with extracranial metastatic germ cell tumors (GCTs) are often treated with regimens developed for children, but their clinical characteristics more closely resemble those of young adult patients. This study was designed to determine event-free survival (EFS) for adolescents with GCTs and compared them with children and young adults. METHODS: An individual patient database of 11 GCT trials was assembled: 8 conducted by pediatric cooperative groups and 3 conducted by an adult group. Male patients aged 0 to 30 years with metastatic, nonseminomatous, malignant GCTs of the testis, retroperitoneum, or mediastinum who were treated with platinum-based chemotherapy were included. The age groups were categorized as children (0 to <11 years), adolescents (11 to <18 years), and young adults (18 to ≤30 years). The study compared EFS and adjusted for risk group by using Cox proportional hazards analysis. RESULTS: From a total of 2024 individual records, 593 patients met the inclusion criteria: 90 were children, 109 were adolescents, and 394 were young adults. The 5-year EFS rate was lower for adolescents (72%; 95% confidence interval [CI], 62%-79%) than children (90%; 95% CI, 81%-95%; P = .003) or young adults (88%; 95% CI, 84%-91%; P = .0002). The International Germ Cell Cancer Collaborative Group risk group was associated with EFS in the adolescent age group (P = .0020). After adjustments for risk group, the difference in EFS between adolescents and children remained significant (hazard ratio, 0.30; P = .001). CONCLUSIONS: EFS for adolescent patients with metastatic GCTs was similar to that for young adults but significantly worse than for that children. This finding highlights the importance of coordinating initiatives across clinical trial organizations to improve outcomes for adolescents and young adults. LAY SUMMARY: Adolescent males with metastatic germ cell tumors (GCTs) are frequently treated with regimens developed for children. In this study, a large data set of male patients with metastatic GCTs across different age groups has been built to understand the outcomes of adolescent patients in comparison with children and young adults. The results suggest that adolescent males with metastatic GCTs have worse results than children and are more similar to young adults with GCTs. Therefore, the treatment of adolescents with GCTs should resemble therapeutic approaches for young adults.

Development of a Data Model and Data Commons for Germ Cell Tumors.

Germ cell tumors (GCTs) are considered a rare disease but are the most common solid tumors in adolescents and young adults, accounting for 15% of all malignancies in this age group. The rarity of GCTs in some groups, particularly children, has impeded progress in treatment and biologic understanding. The most effective GCT research will result from the interrogation of data sets from historical and prospective trials across institutions. However, inconsistent use of terminology among groups, different sample-labeling rules, and lack of data standards have hampered researchers' efforts in data sharing and across-study validation. To overcome the low interoperability of data and facilitate future clinical trials, we worked with the Malignant Germ Cell International Consortium (MaGIC) and developed a GCT clinical data model as a uniform standard to curate and harmonize GCT data sets. This data model will also be the standard for prospective data collection in future trials. Using the GCT data model, we developed a GCT data commons with data sets from both MaGIC and public domains as an integrated research platform. The commons supports functions, such as data query, management, sharing, visualization, and analysis of the harmonized data, as well as patient cohort discovery. This GCT data commons will facilitate future collaborative research to advance the biologic understanding and treatment of GCTs. Moreover, the framework of the GCT data model and data commons will provide insights for other rare disease research communities into developing similar collaborative research platforms.

Screening for Pineal Trilateral Retinoblastoma Revisited: A Meta-analysis.

TOPIC: To determine the age up to which children are at risk of trilateral retinoblastoma (TRb) developing, whether its onset is linked to the age at which intraocular retinoblastomas develop, and the lead time from a detectable pineal TRb to symptoms. CLINICAL RELEVANCE: Approximately 45% of patients with retinoblastoma-those with a germline RB1 pathogenic variant-are at risk of pineal TRb developing. Early detection and treatment are essential for survival. Current evidence is unclear regarding the usefulness of screening for pineal TRb and, if useful, the age up to which screening should be continued. METHODS: We conducted a study according to the Meta-analysis of Observational Studies in Epidemiology guidelines for reporting meta-analyses of observational studies. We searched PubMed and Embase between January 1, 1966, and February 27, 2019, for published literature. We considered articles reporting patients with TRb with survival and follow-up data. Inclusion of articles was performed separately and independently by 2 authors, and 2 authors also independently extracted the relevant data. They resolved discrepancies by consensus. RESULTS: One hundred thirty-eight patients with pineal TRb were included. Of 22 asymptomatic patients, 21 (95%) were diagnosed before the age of 40 months (median, 16 months; interquartile range, 9-29 months). Age at diagnosis of pineal TRb in patients diagnosed with retinoblastoma at 6 months or younger versus older than 6 months were comparable (P = 0.44), suggesting independence between the ages at diagnosis of intraocular retinoblastoma and pineal TRb. The laterality of intraocular retinoblastoma and its treatment were not associated with the age at which pineal TRb was diagnosed. The lead time from asymptomatic to symptomatic pineal TRb was approximately 1 year. By performing a screening magnetic resonance imaging scan every 6 months after the diagnosis of heritable retinoblastoma (median age, 6 months) until 36 months of age, at least 311 and 776 scans would be required to detect 1 case of asymptomatic pineal TRb and to save a single life, respectively. CONCLUSIONS: Patients with retinoblastoma are at risk of pineal TRb developing for a shorter period than previously assumed, and the age at diagnosis of pineal TRb is independent of the age at diagnosis of retinoblastoma. The GRADE (Grading of Recommendations Assessment, Development and Evaluation) level of evidence for these conclusions remains low.

Germ Cell Tumors in Adolescents and Young Adults.

Germ cell tumors (GCTs) are rare in childhood, representing only 3.5% of childhood cancers, but a common malignancy in adolescents and young adults (AYAs), accounting for 13.9% of neoplasms in adolescents between age 15 and 19 years. The overall outcomes of patients treated for GCTs are excellent. However, as seen in other cancers, outcomes for AYA patients are significantly worse. Understanding the reasons for this observation has led to different approaches to diagnosis, staging, and treatment. The Malignant Germ Cell International Consortium was created to bring together pediatric, gynecologic, and testicular cancer specialists to promote research initiatives and provide evidence-based approaches in the management of GCTs across different age groups. Collaboration between multiple subspecialties is essential to further understand the disease continuum, the underlying biologic characteristics, and the development of appropriate therapeutic approaches. This review focuses on the unique characteristics of patients with extracranial GCTs in the AYA group.