Germ Cell Tumors in Adolescents and Young Adults

Severity of effect considerations regarding the use of mutation as a toxicological endpoint for risk assessment: A report from the 8th International Workshop on Genotoxicity Testing (IWGT)

Exposure levels without appreciable human health risk may be determined by dividing a point of departure on a dose-response curve (e.g., benchmark dose) by a composite adjustment factor (AF). An "effect severity" AF (ESAF) is employed in some regulatory contexts. An ESAF of 10 may be incorporated in the derivation of a health-based guidance value (HBGV) when a "severe" toxicological endpoint, such as teratogenicity, irreversible reproductive effects, neurotoxicity, or cancer was observed in the reference study. Although mutation data have been used historically for hazard identification, this endpoint is suitable for quantitative dose-response modeling and risk assessment. As part of the 8th International Workshops on Genotoxicity Testing, a sub-group of the Quantitative Analysis Work Group (WG) explored how the concept of effect severity could be applied to mutation. To approach this question, the WG reviewed the prevailing regulatory guidance on how an ESAF is incorporated into risk assessments, evaluated current knowledge of associations between germline or somatic mutation and severe disease risk, and mined available data on the fraction of human germline mutations expected to cause severe disease. Based on this review and given that mutations are irreversible and some cause severe human disease, in regulatory settings where an ESAF is used, a majority of the WG recommends applying an ESAF value between 2 and 10 when deriving a HBGV from mutation data. This recommendation may need to be revisited in the future if direct measurement of disease-causing mutations by error-corrected next generation sequencing clarifies selection of ESAF values.

Pediatric oncology drug development and dosage optimization

Oncology drug discovery and development has always been an area facing many challenges. Phase 1 oncology studies are typically small, open-label, sequential studies enrolling a small sample of adult patients (i.e., 3-6 patients/cohort) in dose escalation. Pediatric evaluations typically lag behind the adult development program. The pediatric starting dose is traditionally referenced on the recommended phase 2 dose in adults with the incorporation of body size scaling. The size of the study is also small and dependent upon the prevalence of the disease in the pediatric population. Similar to adult development, the dose is escalated or de-escalated until reaching the maximum tolerated dose (MTD) that also provides desired biological activities or efficacy. The escalation steps and identification of MTD are often rule-based and do not incorporate all the available information, such as pharmacokinetic (PK), pharmacodynamic (PD), tolerability and efficacy data. Therefore, it is doubtful if the MTD approach is optimal to determine the dosage. Hence, it is important to evaluate whether there is an optimal dosage below the MTD, especially considering the emerging complexity of combination therapies and the long-term tolerability and safety of the treatments. Identification of an optimal dosage is also vital not only for adult patients but for pediatric populations as well. Dosage-finding is much more challenging for pediatric populations due to the limited patient population and differences among the pediatric age range in terms of maturation and ontogeny that could impact PK. Many sponsors defer the pediatric strategy as they are often perplexed by the challenges presented by pediatric oncology drug development (model of action relevancy to pediatric population, budget, timeline and regulatory requirements). This leads to a limited number of approved drugs for pediatric oncology patients. This review article provides the current regulatory landscape, incentives and how they impact pediatric drug discovery and development. We also consider different pediatric cancers and potential clinical trial challenges/opportunities when designing pediatric clinical trials. An outline of how quantitative methods such as pharmacometrics/modelling & simulation can support the dosage-finding and justification is also included. Finally, we provide some reflections that we consider helpful to accelerate pediatric drug discovery and development.

Clinical characteristics of malignant germ cell tumors in adolescents: A multicenter 10-year retrospective study in Beijing

Background

The aim of this study was to review clinical features of adolescent malignant germ cell tumors (MGCTs) in Beijing and analyze the peculiar characteristics of this age group.

Methods

Clinical characteristics, pathological presentations, and survival outcomes of 34 patients were analyzed retrospectively.

Results

Of 34 patients, 12 girls and 22 boys, 18 (52.9%) had an extra-cranial tumor, including one testicular tumor, five ovarian tumors, one sacrococcygeal tumor, and 11 mediastinal tumors. Histologically, we found immature teratomas (n = 6), yolk sac tumors (n = 5), mixed malignant tumors (n = 5), an embryonic carcinoma (n = 1), and seminoma (n = 1). Three-year event-free survival (EFS) and overall survival (OS) were 48.8% and 62.9%, respectively. Another 16 (47.1%) patients had an intracranial tumor, including nine in the pineal region, five in the suprasellar region, one in basal ganglia, and one in cerebellopontine. All patients had localized disease and an excellent outcome with 3-year EFS and OS of 93.7% and 100%, respectively.

Conclusions

Adolescent MGCTs are rare with a strong dependence on gender, and the mediastina and pineal region are the most common tumor locations. The prognosis is promising compared with that of other adolescent tumors and MGCTs in other age groups. MGCTs in mediastina have a tendency to companion with other hematological malignancies, and the prognosis is extremely poor in these patients.

Diffusion-weighted imaging in pediatric extracranial germ cell tumors

BACKGROUND

Germ cell tumors (GCTs) comprise a rare and heterogeneous group of neoplasms presenting different clinical and histological characteristics, leading to a challenging scenario in clinical practice. Diffusion-weighted imaging (DWI) has been suggested as an indirect marker of tumor density and cellularity and could be used to monitor therapeutic response. However, its role in pediatric GCTs needs to be clarified.

PURPOSE

Here, we evaluated the features of DWI in pediatric extracranial GCTs in a reference Brazilian institution.

MATERIAL AND METHODS

We included 43 pediatric patients with primary GCTs treated between 2008 and 2022 in Hospital de Amor de Barretos. The patients' MRI images included T1-weighted without contrast, T2-weighted, DWI and apparent diffusion coefficient (ADC) maps. DWI was evaluated in the section that exhibited the greatest restricted diffusion in the largest hypersignal area of the image. The lowest ADC value was determined to define the region of interest (ROI). We used a small ROI, avoiding necrotic, adipose tissue, noisy or nonenhancing lesion voxels as recommended. ROI determination was established by visual inspection by two radiologists in accordance. We used two values of b (b = 50 mm2/s or b = 800) for ADC values.

RESULTS

The highest mean ADC (mADC) value was observed in pure teratomas (1,403.50 ± 161.76 x10-3 mm2/s; mean ± SD) compared to other histologies (yolk sac, mixed teratoma, dysgerminoma and mixed GCT) of GCT (p<0.001). Furthermore, ROC analysis determined a cutoff mADC value of 1,179.00 x 10-3 mm2/s that differentiated pure teratomas from the other GCT histologies with a sensitivity of 95.8% and a specificity of 92.9% (AUC = 0.979; p<0.01). A significant increase in mADC was observed for malignant GCTs in treatment (1,197.00 ± 372.00 mm2/s; p<0.001) compared to that exhibited at the time of diagnosis (780.00 ± 168.00 mm2/s; mean ± SD. Our findings suggest that mADC assessment could be used as a tool to distinguish pure teratomas from malignant CGT histologies at diagnosis. Additionally, we demonstrated reasonable evidence that it could be used as a complementary tool to monitor treatment response in patients with malignant GCT.

Extracranial Germ Cell Tumors in Children: Ten Years of Experience in Three Children's Medical Centers in Shanghai

OBJECTIVE

The aim was to describe the clinical features of extracranial germ cell tumors (GCTs) in pediatrics and study the clinical risk factors related to survival for malignant germ cell tumors (MGCTs) in order to optimize therapeutic options.

METHODS

The clinical data of children with extracranial GCTs in three children's medical centers in Shanghai were retrospectively analyzed.

RESULTS

In total, 1007 cases of extracranial GCTs diagnosed between 2010 and 2019 were included in this study, including teratomas (TERs) 706 (70.11%) and MGCTs 301 (29.89%). There were twice as many TER cases as MGCT cases. Approximately 50% of children with GCTs were <3 years old (43.39% for TERs, 67.13% for MGCTs). GCTs in children of different ages show differences in tumor anatomical locations and pathological subtypes. The 5-year event-free survival (EFS) and overall survival (OS) of all patients with MGCTs were 82.33% (95% CI, 77.32%, 86.62%) and 94.13% (95% CI, 90.02%, 96.69%), respectively. The multivariate Cox regression analysis identified a primary site in the mediastinum and alpha fetoprotein (AFP) levels ≥10,000 ng/mL as independent adverse prognostic factors (p < 0.0.0001, χ2 = 23.6638, p = 0.0225, χ2 = 5.2072.). There were no significant differences in OS among children receiving various chemotherapy regimens, such as the BEP, PEB, JEB and other regimens (VBP/VIP and AVCP/IEV) (p < 0.05).

CONCLUSIONS

The clinical features of GCTs in Chinese pediatrics are similar to those reported in children in Europe and America. The age distribution of pathological types and primary sites in GCTs reflect the developmental origin of type I and type II GCTs transformed from mismigration primordial germ cells (PGCs). Optimizing the current platinum-based chemotherapy regimens and exploring the treatment strategies for MGCTs of the mediastinum are future research directions.

Understanding Sociodemographic Factors among Hispanics Through a Population-Based Study on Testicular Cancer in Mexico

Testicular cancer (TCa) is a rare malignancy affecting young men worldwide. Sociodemographic factors, especially socioeconomic level (SEL) and healthcare access, seem to impact TCa incidence and outcomes, particularly among Hispanic populations. However, limited research has explored these variables in Hispanic groups. This study aimed to investigate sociodemographic and clinical factors in Mexico and their role in health disparities among Hispanic TCa patients. We retrospectively analyzed 244 Mexican TCa cases between 2007 and 2020 of a representative cohort with diverse social backgrounds from a national reference cancer center. Logistic regression identified risk factors for fatality: non-seminoma histology, advanced stage, and lower education levels. Age showed a significant trend as a risk factor. Patient delay and healthcare distance lacked significant associations. Inadequate treatment response and chemotherapy resistance were more likely in advanced stages, while higher education positively impacted treatment response. Cox regression highlighted non-seminoma histology, below-median SEL, higher education, and advanced-stage survival rates. Survival disparities emerged based on tumor histology and patient SEL. This research underscores the importance of comprehensive approaches that integrate sociodemographic, biological, and environmental factors to address health disparities improving outcomes through personalized interventions in Hispanic individuals with TCa.

Systematic Review of the Survival Outcomes of Neoadjuvant Chemotherapy in Women with Malignant Ovarian Germ Cell Tumors

Randomized clinical trials assessing the efficacy of neoadjuvant chemotherapy (NACT) for advanced epithelial ovarian cancer have predominantly included women with high-grade serous carcinomas. The response rate and oncological outcomes of NACT for malignant ovarian germ cell tumors (MOGCT) are poorly understood. This study aimed to examine the effects of NACT on women with MOGCT by conducting a systematic review of four public search engines. Fifteen studies were identified, and a further descriptive analysis was performed for 10 original articles. In those studies, most women were treated with a bleomycin, etoposide, and cisplatin regimen, and one to three cycles were used in most studies. Four studies comparing NACT and primary debulking surgery showed similar complete response rates (n = 2; pooled odds ratio [OR] 0.90, 95% confidence interval [CI] 0.15-5.27), comparable overall survival (n = 3; 87.0-100% versus 70.0-100%), disease-free survival (n = 3; 87.0-100% versus 70.0-100%), recurrence rate (n = 1; OR 3.50, 95%CI 0.38-32.50), and adverse events rate from chemotherapy between the groups. In conclusion, NACT may be considered for the management of MOGCT; however, possible candidates for NACT use and an ideal number of NACT cycles remain unknown. Further studies are warranted to validate the efficacy of NACT in advanced MOGCT patients.

Role of Alpha-Fetoprotein (AFP) in Diagnosing Childhood Cancers and Genetic-Related Chronic Diseases

Alpha-fetoprotein (AFP) is a protein commonly found during fetal development, but its role extends beyond birth. Throughout the first year of life, AFP levels can remain high, which can potentially mask various conditions from the neurological, metabolic, hematological, endocrine, and early childhood cancer groups. Although AFP reference values and clinical utility have been established in adults, evaluating AFP levels in children during the diagnostic process, treatment, and post-treatment surveillance is still associated with numerous diagnostic pitfalls. These challenges arise from the presence of physiologically elevated AFP levels, inconsistent data obtained from different laboratory tests, and the limited population of children with oncologic diseases that have been studied. To address these issues, it is essential to establish updated reference ranges for AFP in this specific age group. A population-based study involving a statistically representative group of patients could serve as a valuable solution for this purpose.

Analysis of microsatellite instability (MSI) in pediatric gonadal and extra-gonadal germ cell tumors

Gonadal and extragonadal pediatric germ cell tumors (GCTs) are rare neoplasms with different clinical behavior. Although surgery and cisplatin-based chemotherapy are resolutive in most cases, some patients do not respond to chemotherapy and have a worse outcome. Microsatellite instability (MSI) was correlated to resistance to chemotherapy and sensitivity to immunotherapy in different neoplasms. A series of 21 pediatric GCTs were tested by immuno-histochemistry and PCR to evaluate MSI status. Next generation sequencing was applied to further evaluate cases with discordant results between immunohistochemistry and PCR. Twenty-one cases of pediatric GCT were included in the series. The mean age ranged between 1 and 10 years. Nine cases were gonadal GCTs and the remaining 12 were extra-gonadal GCTs. By immunohistochemistry, one case showed a deficit of Mismatch repair (MMR) proteins. This case was a 1-year-old children affected by gonadal yolk sac tumor. However, all cases resulted microsatellite stable (MSS) by PCR and NGS. MSI was not detected in our series of pediatric GCTs, as well as the data present in literature about adult patients with GCTs. Molecular techniques could have a role to confirm the MSI status in case of dMMR by immunohistochemistry.

Imaging of pediatric ovarian tumors: A COG Diagnostic Imaging Committee/SPR Oncology Committee White Paper

Ovarian tumors in children are uncommon. Like those arising in the adult population, they may be broadly divided into germ cell, sex cord, and surface epithelium subtypes; however, germ cell tumors comprise the majority of lesions in children, whereas tumors of surface epithelial origin predominate in adults. Diagnostic workup, including the use of imaging, requires an approach that often differs from that required in an adult. This paper offers consensus recommendations for imaging of pediatric patients with a known or suspected primary ovarian malignancy at diagnosis and during follow-up.

Spermatocytic Tumor: A Review

Spermatocytic tumor (ST) is a very rare disease, accounting for approximately 1% of testicular cancers. Previously classified as spermatocytic seminoma, it is currently classified within the non-germ neoplasia in-situ-derived tumors and has different clinical-pathologic features when compared with other forms of germ cell tumors (GCTs). A web-based search of MEDLINE/PubMed library data was performed in order to identify pertinent articles. In the vast majority of cases, STs are diagnosed at stage I and carry a very good prognosis. The treatment of choice is orchiectomy alone. Nevertheless, there are two rare variants of STs having very aggressive behavior, namely anaplastic ST and ST with sarcomatous transformation, that are resistant to systemic treatments and their prognosis is very poor. We have summarized all the epidemiological, pathological and clinical features available in the literature regarding STs that have to be considered as a specific entity compared to other germ GCTs, including seminoma. With the aim of improving the knowledge of this rare disease, an international registry is required.

Loss to follow-up of minorities, adolescents, and young adults on clinical trials: A report from the Children's Oncology Group

BACKGROUND

The increasing number of childhood cancer survivors necessitates continued follow-up to monitor for long-term complications. Inequities in loss to follow-up for patients enrolled on pediatric clinical trials have not been well studied.

METHODS

This was a retrospective study of 21,084 patients residing in the United States enrolled on phase 2/3 and phase 3 Children's Oncology Group (COG) trials between January 1, 2000 and March 31, 2021. Rates of loss to follow-up to COG were evaluated using log-rank tests and multivariable Cox proportional hazards regression models with adjusted hazard ratios (HRs). Demographic characteristics included age at enrollment, race, ethnicity, and zip code level socioeconomic data.

RESULTS

Adolescent and young adult (AYA) patients 15-39 years old at diagnosis had an increased hazard of loss to follow-up compared to patients 0-14 years old (HR, 1.89; 95% confidence interval (CI), 1.76-2.02). In the overall cohort, non-Hispanic Blacks were found to have an increased hazard of loss to follow-up compared to non-Hispanic Whites (HR, 1.56; 95% CI, 1.43-1.70). Among AYAs, the highest loss to follow-up rates were among non-Hispanic Blacks (69.8% ± 3.1%), patients on germ cell tumor trials (78.2% ± 9.2%), and patients living in zip codes with a median household income ≤150% of the federal poverty line at diagnosis (66.7% ± 2.4%).

CONCLUSIONS

AYAs, racial and ethnic minority patients, and those living in lower socioeconomic status areas had the highest rates of loss to follow-up among clinical trial participants. Targeted interventions are warranted to ensure equitable follow-up and improved assessment of long-term outcomes.

PLAIN LANGUAGE SUMMARY

Little is known about disparities in loss to follow-up for pediatric cancer clinical trial participants. In this study, we found that participants who were adolescents and young adults when treated, those who identified as a racial and/or ethnic minority, or those residing in areas with lower socioeconomic status at diagnosis were associated with higher rates of loss to follow-up. As a result, the ability to assess their long-term survival, treatment-related health conditions, and quality of life is hindered. These findings suggest the need for targeted interventions to improve long-term follow-up among disadvantaged pediatric clinical trial participants.

Therapeutic Management and Prognostic Factors for Ovarian Malignant Tumours in Adolescents: A Comprehensive Review of Current Guidelines

Background: Ovarian malignant tumours are rarely diagnosed in adolescents but may have a significant impact on their survival, future fertility and quality of life. The management of such cases is rather complex and requires expertise and careful planning according to scarce existing evidence and recommendations. Objective: The aim of this study was to review and compare recommendations from published guidelines regarding the diagnosis, prognosis and treatment of malignant ovarian tumours in adolescents. Evidence acquisition: A comparative descriptive/narrative review of guidelines issued by L’Observatoire des Tumeurs Malignes Rares Gynécologiques, the British Society for Paediatric & Adolescent Gynaecology, the European Society for Medical Oncology, the European Society of Gynecological Oncology-European Society for Paediatric Oncology and the European Cooperative Study Group for Pediatric Rare Tumors was conducted. Results: All guidelines recommend a thorough diagnostic work-up, consisting of both imaging tests and serum tumour marker measurement, as well as the use of immunohistochemical methods to confirm the diagnosis and complete surgical staging prior to constructing the treatment plan. There is a lack of recommendations regarding the assessment of prognostic factors, with only one guideline providing detailed information. Treatment strategies, as suggested by the majority of guidelines and with only a few discrepancies between them, should include both surgery and adjuvant therapies, mainly chemotherapy, with great emphasis on fertility preservation when it is considered oncologically safe and on the significance of regular and long-term follow-up. Conclusions: There is a significant degree of agreement among recommendations of existing guidelines. The reported differences, although limited, highlight the need for the adoption of an international consensus in order to further improve the management of adolescent ovarian cancer.

Bimodal Age Distribution in Cancer Incidence

Cancer is caused by accumulation of genetic changes which include activation of protooncogenes and loss of tumor suppressor genes. The age-specific incidence of cancer in general increases with advancing age. However, some cancers exhibit a bimodal distribution. Commonly recognized cancers with bimodal age distribution include acute lymphoblastic leukemia, osteosarcoma, Hodgkin's lymphoma, germ cell tumors and breast cancer. Delayed infection hypothesis has been used to provide explanation for the early childhood peak in leukemias and lymphomas, whereas the peak at an older age is associated with accumulation of protooncogenes and weakened immune system. Further genetic analysis and histopathological variations point to distinctly different cancers, varying genetically and histologically, which are often combined under a single category of cancers. Tumor characteristics and age distribution of these cancers varies also by population groups and has further implications on cancer screening methods. Although significant advances have been made to explain the bimodal nature of such cancers, the specific genetic mechanisms for each age distribution remain to be elucidated. Further distinction among the different cancer subtypes may lead to improvements in individual risk assessments, prevention and enhancement of treatment strategies.

Insights on Lipomatosis after Platinum-Based Chemotherapy Use in Pediatric Oncology: A Case Report

Agents of platinum-based chemotherapy, such as cisplatin or carboplatin, are used in the treatment of a wide range of malignancies that affect children, such as brain tumors, osteosarcoma, neuroblastoma, hepatoblastoma, and germ cell tumors (GCTs). The Cyclophosphamide Equivalent Dose (CED) calculator for reproductive risk does not take platinum-based chemotherapy into account, despite the fact that it accounts for the majority of chemotherapy medications that are typically administered for pediatric GCTs. As a result, exposure to platinum-based drugs throughout infancy can have predictable long-term effects such as infertility, as well as other rare encounters such as lipoma formation and lipomatosis. Lipomas are the most prevalent benign soft tissue tumor subtype. They may be either solitary entities or engaged in multiple lipomatosis, which may have a familial origin or be an acquired disorder. Chemotherapy is a possible cause of lipomatosis. Chemotherapy based on cisplatin has been linked to a variety of long-term consequences, including kidney damage, neurotoxicity, and pulmonary toxicity, and may even create secondary cancers. However, lipoma development is known to occur in fewer than 1 in 100 individuals, and only a few examples of multiple cutaneous lipomatosis triggered by this therapy have been documented. Here we present a very rare case of lipomatosis in a pediatric patient with GCT under cisplatin therapy, which might be the third report of this kind affecting children.

Advancing clinical and translational research in germ cell tumours (GCT): recommendations from the Malignant Germ Cell International Consortium

Germ cell tumours (GCTs) are a heterogeneous group of rare neoplasms that present in different anatomical sites and across a wide spectrum of patient ages from birth through to adulthood. Once these strata are applied, cohort numbers become modest, hindering inferences regarding management and therapeutic advances. Moreover, patients with GCTs are treated by different medical professionals including paediatric oncologists, neuro-oncologists, medical oncologists, neurosurgeons, gynaecological oncologists, surgeons, and urologists. Silos of care have thus formed, further hampering knowledge dissemination between specialists. Dedicated biobank specimen collection is therefore critical to foster continuous growth in our understanding of similarities and differences by age, gender, and site, particularly for rare cancers such as GCTs. Here, the Malignant Germ Cell International Consortium provides a framework to create a sustainable, global research infrastructure that facilitates acquisition of tissue and liquid biopsies together with matched clinical data sets that reflect the diversity of GCTs. Such an effort would create an invaluable repository of clinical and biological data which can underpin international collaborations that span professional boundaries, translate into clinical practice, and ultimately impact patient outcomes.

Hallazgos incidentales en cirugía abdominal: masas y sarcomas retroperitoneales

Introducción. El retroperitoneo es una estructura que se extiende desde el diafragma hasta la pelvis, está delimitado adelante por el peritoneo parietal, atrás y a los lados por la fascia transversalis y se divide en 9 compartimientos. Se pueden encontrar lesiones primarias o secundarias, cuya evolución clínica varía desde un curso indolente hasta rápidamente progresivo, tanto local como a distancia. Su enfoque, desde el hallazgo hasta el tratamiento, es fundamental para el desenlace oncológico. Objetivo. Analizar la evaluación, el diagnóstico y el tratamiento de las masas retroperitoneales halladas incidentalmente y brindar un algoritmo de manejo. Métodos. Se hizo búsqueda en bases de datos como PubMed y MedicalKey de literatura referentes a tumores retroperitoneales, su diagnóstico y enfoque terapéutico, con el fin de presentar una revisión sobre el abordaje de las masas retroperitoneales y dar nuestras opiniones. Resultados. Se revisaron 43 referencias bibliográficas internacionales y nacionales, y se seleccionaron 20 de ellas, de donde se obtuvieron datos actualizados, recomendaciones de guías internacionales y experiencias nacionales, con lo cual se estructuró este manuscrito. Conclusiones. Las masas retroperitoneales abarcan un espectro de patologías que establecen un reto diagnóstico por su origen embriológico, localización y baja frecuencia. El diagnostico histológico es de vital importancia desde el inicio, para conocer la evolución natural de la enfermedad, y el manejo multidisciplinario en centros de referencia es fundamental para impactar en los desenlaces oncológicos. Existen variadas modalidades terapéuticas, como quimioterapia, radioterapia y resección quirúrgica con estándares oncológicos.

Immunohistochemical Expression of Preferentially Expressed Antigen in Melanoma (PRAME) in the Uninvolved Background Testis, Germ Cell Neoplasia In Situ, and Germ Cell Tumors of the Testis

OBJECTIVES

Preferentially expressed antigen in melanoma (PRAME) has a key role in regulating pluripotency of primordial germ cells and in the development of germ cell tumors of the testis (GCTT). However, its immunohistochemical expression in normal testes and its neoplastic counterpart remain largely unknown.

METHODS

We retrospectively investigated the expression of PRAME in 26 cases of GCTT, 21 cases of germ cell neoplasia in situ (GCNIS), and 17 cases of uninvolved background testes.

RESULTS

We found that PRAME was expressed more strongly by seminomatous rather than nonseminomatous GCTT (P = .000) and by pure seminoma rather than the seminoma component of seminomatous/nonseminomatous GCTT (P = .025). In addition, GCNIS and uninvolved background testes displayed high levels of PRAME expression.

CONCLUSIONS

PRAME is an additional marker for the differential diagnosis of GCTT and could play a key role in the transition from seminomatous to nonseminomatous GCTT.

Update on pediatric testicular germ cell tumors

BACKGROUND

Testicular germ cell tumors are uncommon tumors that are encountered by pediatric surgeons and urologists and require a knowledge of appropriate contemporary evaluation and surgical and medical management.

METHOD

A review of the recommended diagnostic evaluation and current surgical and medical management of children and adolescents with testicular germ cell tumors based upon recently completed clinical trials was performed and summarized in this article.

RESULTS

In this summary of childhood and adolescent testicular germ cell tumors, we review the initial clinical evaluation, surgical and medical management, risk stratification, results from recent prospective cooperative group studies, and clinical outcomes. A summary of recently completed clinical trials by pediatric oncology cooperative groups is provided, and best surgical practices are discussed.

CONCLUSIONS

Testicular germ cell tumors in children are rare tumors. International collaborations, data-sharing, and enrollment of patients at all stages and risk classifications into active clinical trials will enhance our knowledge of these rare tumors and most importantly improve outcomes of patients with testicular germ cell tumors.

LEVEL OF EVIDENCE

This is a review article of previously published and referenced level 1 and 2 studies, but also includes expert opinion level 5, represented by the American Pediatric Surgical Association Cancer Committee.

Diagnostic, Prognostic and Predictive Markers in Pediatric Germ Cell Tumors—Past, Present and Future

Germ cell tumors (GCTs) are a heterogenous group of neoplasms in children and young adults, in which serum tumor markers have been demonstrated to be highly sensitive diagnostic and monitoring tools. The known "old" serum biomarkers, alpha-fetoprotein (AFP), human choriogonadotropin (β-hCG) and lactate dehydrogenase (LDH), have some limitations in sensitivity and specificity. MIRNAs from the miR-371~373 (chromosomal locus 19q13.41) and miR-302/367 (4q25) clusters are universally over-expressed in malignant GCT tissue samples. The levels of miRNAs from these clusters are elevated in the serum. They seem to be highly sensitive and specific in malignant GCTs diagnosis and disease assessment during treatment and follow-up. The aim of our review was to present the role of serum tumor markers in the clinical staging, treatment monitoring and follow-up of pediatric patients with GCTs and show new possibilities. The serum levels of miRNAs seem to be a new, promising essential tool in the clinical management of GCTs.

Genitourinary Tract Tumors in Children: An Update

BACKGROUND

Genitourinary tract tumors in children are less common than in adults. Most of these tumors have different genetic backgrounds, clinical presentation, and oncologic behavior than their adult counterpart. As a result of low prevalence in children, some of the treatment approaches and recommendations are based on treatment experience in adult patients. However, thanks to scientific and technological development, survival rates have risen considerably.

OBJECTIVE

This paper presents a review of the principal features of the tumors involving the genitourinary tract in children and an update in genetic background, diagnosis, and treatment.

METHODS

A narrative review was performed on published literature about genitourinary tract tumors in pediatric patients. Papers presented in English and Spanish literature were reviewed. PubMed, Science Direct, and SciELO databases were used to collect information and present this article.

RESULTS

Kidney tumors are the most common type of genitourinary tumors in children. Among those, Wilms tumor represents the majority of cases and shows the successful work of clinical trial groups studying this tumor type. Other tumors involving the genitourinary tract in children include Rhabdomyosarcoma, Transitional cell carcinoma, Testicular, and Adrenal tumors.

CONCLUSION

Genitourinary tract tumors in children represent significant morbidity and economic burden, so awareness in early diagnosis represents improvement in treatment, clinical, and oncological outcomes.

New aspects and innovations in the local treatment of renal and urogenital pediatric tumors

Local treatment plays a key role for patients' outcome in tumors of the urogenital tract in children. Despite a great variety of different etiologies, the specific localization of pediatric urogenital tumors renders several characteristic demands to the treating personnel. Surgery and radiotherapy are the main elements of local treatment in this group of neoplasms. Numerous new guidelines and innovative technical developments of surgery and radiotherapy have recently been integrated into treatment concepts for pediatric urogenital tumors. Due to the broadness of the field it is not possible to give a full overview over all aspects. Therefore, this article highlights the most important innovations and new guidelines of surgery and radiotherapy of pediatric urogenital tumors.

Treatment and Survival of Malignant Extracranial Germ Cell Tumours in the Paediatric Population: A Systematic Review and Meta-Analysis

OBJECTIVE

This systematic review and meta-analysis was performed to explore overall survival (OS) and event free survival (EFS) rates internationally over the past two decades and to define specific subgroups with inferior outcomes which may demand different treatment strategies.

METHODS

The search focused on malignant extracranial germ cell tumours (GCTs) in the paediatric population. The initial database search identified 12,556 articles; 32 articles were finally included in this review, comprising a total of 5095 patients.

RESULTS

The studies were heterogeneous, varying from single institution reports to large prospective trials. Older studies, describing eras where non-platinum-based chemotherapy regimens were used, showed clearly worse outcomes. Survival for stage I-II gonadal disease is excellent. On the other hand, patients with an initial alpha-fetoprotein (AFP) > 10,000 ng/mL or kU/L, age > 11 years and stage IV disease confer a survival disadvantage. For testicular disease in particular, lymphovascular invasion and certain histopathological subtypes, such as embryonal carcinoma (EC) and mixed malignant GCTs, survival is poorer. Survival data for sacrococcygeal and mediastinal GCTs show a heterogeneous distribution across studies in this review, independent of year of publication. Patients > 12 years presenting with a mediastinal GCT pose a subpopulation which fares worse than GCTs in other locations or age groups. This is independent of AFP levels, stage of disease or treatment protocol, and these patients may demand a different treatment strategy.

CONCLUSIONS

This review describes the heterogeneous nature of GCTs in different anatomical locations, impacting on stage at presentation, treatment modalities used and survival data. Despite this heterogeneity, in line with the current developmental biology-based classification system, subpopulations can be defined which have an inferior EFS and OS and where future research and more individualised treatment would help to improve survival.

Surveillance Only for High-risk FIGO Stage IA/IB Malignant Ovarian Germ Cell Tumors: Results From a National Cancer Database

OBJECTIVES

Investigate the use and outcomes of a surveillance only strategy for patients with high-risk stage I malignant ovarian germ cell tumors.

METHODS

Patients with International Federation of Gynecology and Obstetrics stage IA/IB grade 2 or 3 immature teratoma, yolk sac, or mixed germ cell tumor diagnosed between 2004 and 2014 who had at least 1 month of follow-up were drawn from the National Cancer Database. Overall survival (OS) was evaluated for each histologic subtype using Kaplan-Meier curves, and compared with the log-rank test.

RESULTS

A total of 497 patients were identified; 115 (23.1%) with grade 2 immature teratoma, 157 (31.6%) with grade 3 immature teratoma, 101 (20.3%) with yolk sac tumor, 124 (25%) with mixed germ cell tumor. Rate of adjuvant chemotherapy was 68.2% (655 patients), while rate of lymph node biopsy/dissection was 55.2%. A total of 19 (3.8%) deaths were observed at a median of 29.8 months. There was no difference in OS between patients who did and did not receive adjuvant chemotherapy with grade 2 (P=0.35) and grade 3 immature teratoma (P=0.47) or mixed germ cell tumors (P=0.55). Patients with yolk sac tumors those who received chemotherapy had better OS compared with those who did not, P=0.019; 5-year OS rates were 92.7% and 79.6%, respectively.

CONCLUSIONS

A surveillance only strategy for patients with stage I malignant ovarian germ cell tumors is associated with excellent survival outcomes for patients with grade 2 or 3 immature teratoma or mixed germ cell tumors.

Gynecologic cancer in pregnancy

Cancer complicates 1 in 1000 pregnancies. Multidisciplinary consensus comprised of Gynecologic Oncology, Pathology, Neonatology, Radiology, Anesthesiology, Maternal Fetal Medicine, and Social Work should be convened. Pregnancy provides an opportunity for cervical cancer screening, with deliberate delays in treatment permissible for early stage carcinoma. Vaginal delivery is contraindicated in the presence of gross lesion(s) and radical hysterectomy with lymphadenectomy at cesarean delivery is recommended. Women with locally advanced and metastatic/recurrent disease should commence treatment at diagnosis with chemoradiation and systemic therapy, respectively; neoadjuvant chemotherapy to permit gestational advancement may be considered in select cases. Most adnexal masses are benign and resolve by the second trimester. Persistent, asymptomatic, benign-appearing masses can be managed conservatively; surgery, if indicated, is best deferred to 15-20 weeks, with laparoscopy preferable over laparotomy whenever possible. Benign and malignant germ cell tumors and borderline tumors are occasionally encountered, with unilateral adnexectomy and preservation of the uterus and contralateral ovary being the rule. Epithelial ovarian cancer is exceedingly rare. Ultrasonography and magnetic resonance imaging lack ionizing radiation and can be employed to evaluate disease extent. Tumor markers, including CA-125, AFP, LDH, inhibin-B, and even CEA and ßhCG may be informative. If required, chemotherapy can be administered following organogenesis during the second and third trimesters. Because platinum and other anti-neoplastic agents cross the placenta, chemotherapy should be withheld after 34 weeks to avoid neonatal myelosuppression. Bevacizumab, immune checkpoint inhibitors, and PARP inhibitors should be avoided throughout pregnancy. Although antenatal glucocorticoids to facilitate fetal pulmonary maturation and amniotic fluid index assessment can be considered, there is no demonstrable benefit of tocolytics, antepartum fetal heart rate monitoring, and/or amniocentesis. Endometrial, vulvar, and vaginal cancer in pregnancy are curiosities, although leiomyosarcoma and the dreaded twin fetus/hydatidiform mole have been reported. For gynecologic malignancies, pregnancy does not impart aggressive clinical behavior and/or worse prognosis.

Molecular and epigenetic pathogenesis of germ cell tumors

The development of germ cell tumors (GCTs) is a unique pathogenesis occurring at an early developmental stage during specification, migration or colonization of primordial germ cells (PGCs) in the genital ridge. Since driver mutations could not be identified so far, the involvement of the epigenetic machinery during the pathogenesis seems to play a crucial role. Currently, it is investigated whether epigenetic modifications occurring between the omnipotent two-cell stage and the pluripotent implanting PGCs might result in disturbances eventually leading to GCTs. Although progress in understanding epigenetic mechanisms during PGC development is ongoing, little is known about the complete picture of its involvement during GCT development and eventual classification into clinical subtypes. This review will shed light into the current knowledge of the complex epigenetic and molecular contribution during pathogenesis of GCTs by emphasizing on early developmental stages until arrival of late PGCs in the gonads. We questioned how misguided migrating and/or colonizing PGCs develop to either type I or type II GCTs. Additionally, we asked how pluripotency can be regulated during PGC development and which epigenetic changes contribute to GCT pathogenesis. We propose that SOX2 and SOX17 determine either embryonic stem cell-like (embryonal carcinoma) or PGC-like cell fate (seminoma). Finally, we suggest that factors secreted by the microenvironment, i.e. BMPs and BMP inhibiting molecules, dictate the fate decision of germ cell neoplasia in situ (into seminoma and embryonal carcinoma) and seminomas (into embryonal carcinoma or extraembryonic lineage), indicating an important role of the microenvironment on GCT plasticity.