Intracranial Germ Cell Tumor in the Molecular Era

Suprasellar teratoma to germinoma recurrence: implications for diagnosis and follow-up

Mature teratoma is a subtype of intracranial germ cell tumors (GCTs), distinguished from malignant GCTs by its benign nature and excellent prognosis. Typically, no adjuvant therapy is recommended following gross total resection (GTR). We report a case of a prepubertal girl with a suprasellar mature teratoma that recurred as a germinoma 6 months post-GTR. A 7-year-old girl presented with headache and polydipsia. Imaging revealed a suprasellar mass. The patient underwent GTR, and pathological diagnosis confirmed a mature teratoma without other GCT components. Six months later, MRI identified a newly developed suprasellar mass adjacent to the optic chiasm. A second surgery confirmed the mass as a germinoma. The patient subsequently underwent adjuvant chemotherapy combined with proton therapy, resulting in complete remission. The diagnosis of mature teratoma must be approached with caution, and thorough follow-up is imperative, particularly in cases involving female patients, prepubertal age, or non-pineal locations.

Imaging in malignant germ cell tumors involving the hypothalamo-neurohypophyseal axis: the evaluation of the posterior pituitary bright spot is essential

PURPOSE

Malignant intracranial germ cell tumors (GCTs) are rare diseases in Western countries. They arise in midline structures and diagnosis is often delayed. We evaluated imaging characteristics and early tumor signs of suprasellar and bifocal GCT on MRI.

METHODS

Patients with the diagnosis of a germinoma or non-germinomatous GCT (NGGCT) who received non-contrast sagittal T1WI on MRI pre-therapy were included. Loss of the posterior pituitary bright spot (PPBS), the expansion and size of the tumor, and the expansion and infiltration of surrounding structures were evaluated. Group comparison for histologies and localizations was performed.

RESULTS

A total of 102 GCT patients (median age at diagnosis 12.3 years, range 4.4-33.8; 57 males; 67 in suprasellar localization) were enrolled in the study. In the suprasellar cohort, NGGCTs (n = 20) were noticeably larger than germinomas (n = 47; p < .001). Each tumor showed involvement of the posterior lobe or pituitary stalk. A PPBS loss (total n = 98) was observed for each localization and entity in more than 90% and was related to diabetes insipidus. Osseous infiltration was observed exclusively in suprasellar GCT (significantly more frequent in NGGCT; p = .004). Time between the first MRI and therapy start was significantly longer in the suprasellar cohort (p = .005), with an even greater delay in germinoma compared to NGGCT (p = .002). The longest interval to treatment had circumscribed suprasellar germinomas (median 312 days).

CONCLUSION

A loss of the PPBS is a hint of tumor origin revealing small tumors in the neurohypophysis. Using this sign in children with diabetes insipidus avoids a delay in diagnosis.

Intracranial Germinoma in Two Caucasian American Siblings With Autism Spectrum Disorder

Intracranial germ cell tumors (IGCTs) comprise 3% to 5% of all pediatric brain tumors in the West, with a significantly higher prevalence in Asia. Although these tumors are histologically diverse, repeated somatic variants have been demonstrated. Chromosomal aneuploidies, such as Klinefelter and Down syndromes, are associated with IGCTs, but no familial germline tumor syndromes are currently known. Here, we report the novel case of 2 American siblings with underlying autism spectrum disorder who developed intracranial germinoma within months of each other, in the absence of external risk factors. Extensive genetic testing was performed, including karyotyping, chromosomal microarray, and whole exome and whole genome sequencing, and did not identify any variants accounting for the phenotypes. Despite the absence of overlapping variants, a recent retrospective review demonstrated a threefold greater prevalence of autism spectrum disorder in patients with intracranial germinoma compared with national prevalence. This report highlights the complexity of tumor development, as well as the need for further research regarding IGCTs in a neurodivergent population.

Advances in genetic abnormalities, epigenetic reprogramming, and immune landscape of intracranial germ cell tumors

Intracranial germ cell tumors (IGCTs) are a rare subtype of central nervous system neoplasms that predominantly affect young individuals and exhibit a higher incidence in East Asia. IGCTs can be pathologically divided into two main categories: germinomas and non-germinomatous germ cell tumors (NGGCTs). Despite the scarcity of this disease, recent advancements in molecular biology techniques have facilitated the discovery of the inherent genetic and molecular characteristics of IGCTs. Somatic mutations that result in the activation of the KIT/RAS/MAPK and PI3K/AKT/mTOR pathways, chromosomal instability leading to characteristic changes in chromosomal fragments (notably 12p gain), and potentially diagnostic miRNAs (such as miR-371a-3p) may provide valuable insights for the efficient diagnosis, targeted therapy, and prognosis evaluation of IGCTs. Additionally, transcriptomic and methylomic analyses have provided new perspectives on the intrinsic development of IGCTs, further elucidating their equivalence with GCTs at other sites. The evaluation of the tumor immune landscape may guide prognosis prediction and immunotherapy for IGCT patients. Nevertheless, current research still faces challenges such as the absence of basic laboratory research systems, a single source of large sample research data, and a limited overall volume of research. The incorporation of larger sample sizes, the implementation of more innovative evaluation systems, and the employment of novel experimental methods are urgently required to become the focus of future research.

Cancer Stem Cells in Tumours of the Central Nervous System in Children: A Comprehensive Review

Cancer stem cells (CSCs) are a subgroup of cells found in various kinds of tumours with stem cell characteristics, such as self-renewal, induced differentiation, and tumourigenicity. The existence of CSCs is regarded as a major source of tumour recurrence, metastasis, and resistance to conventional chemotherapy and radiation treatment. Tumours of the central nervous system (CNS) are the most common solid tumours in children, which have many different types including highly malignant embryonal tumours and midline gliomas, and low-grade gliomas with favourable prognoses. Stem cells from the CNS tumours have been largely found and reported by researchers in the last decade and their roles in tumour biology have been deeply studied. However, the cross-talk of CSCs among different CNS tumour types and their clinical impacts have been rarely discussed. This article comprehensively reviews the achievements in research on CSCs in paediatric CNS tumours. Biological functions, diagnostic values, and therapeutic perspectives are reviewed in detail. Further investigations into CSCs are warranted to improve the clinical practice in treating children with CNS tumours.

Update on MRI in pediatric intracranial germ cell tumors-The clinical and radiological features

Intracranial germ cell tumors (iGCTs) are uncommon brain tumors that mainly occur in children. Differing in histology, location, and gender of the patients, iGCTs are often divided into germinomas and non-germinomatous germ cell tumors (NGGCTs). Early diagnosis and timely treatment are crucial to iGCTs, the subtypes of which have substantial variations. This review summarized the clinical and radiological features of iGCTs at different sites, and reviewed the recent advances in neuroimaging of iGCTs, which can help predict tumor subtypes early and guide clinical decision-making.

A case series and literature review on 98 pediatric patients of germ cell tumor developing growing teratoma syndrome

INTRODUCTION

Malignant germ cell tumors (MGCTs) can develop either extracranially or intracranially. Growing teratoma syndrome (GTS) may develop in these patients following chemotherapy. Reports on the clinical characteristics and outcomes of GTS in children with MGCTs are limited.

METHODS

We retrospectively collected the data, including the clinical characteristics and outcomes of five patients in our series and 93 pediatric patients selected through a literature review of MGCTs. This study aimed to analyze survival outcomes and risk factors for subsequent events in pediatric patients with MGCTs developing GTS.

RESULTS

The sex ratio was 1.09 (male/female). In total, 52 patients (53.1%) had intracranial MGCTs. Compared with patients with extracranial GCTs, those with intracranial GCTs were younger, predominantly boys, had shorter intervals between MGCT and GTS, and had GTS mostly occurring over the initial site (all p < 0.001). Ninety-five patients (96.9%) were alive. However, GTS recurrence (n = 14), GTS progression (n = 9), and MGCT recurrence (n = 19) caused a substantial decrease in event-free survival (EFS). Multivariate analyses showed that the only significant risk factors for these events were incomplete GTS resection and different locations of GCT and GTS. Patients without any risk had a 5-year EFS of 78.8% ± 7.8%, whereas those with either risk had 41.7% ± 10.2% (p < 0.001).

CONCLUSION

For patients with high-risk features, every effort should be made to closely monitor, completely remove, and pathologically prove any newly developed mass to guide relevant treatment. Further studies incorporating the risk factors into treatment strategies may be required to optimize adjuvant therapy.

Histogenesis of intracranial germ cell tumors: primordial germ cell vs. embryonic stem cell

INTRODUCTION

Intracranial germ cell tumor (iGCT) is a rare disorder and often occurs during childhood and adolescence. iGCTs are frequently localized in pineal region and hypothalamic-neurohypophyseal axis (HNA). In spite of well-established clinical and pathological entity, histogenesis of iGCTs remains unsettled. Current theories of histogenesis of iGCTs include germ cell theory (from primordial germ cells (PGCs) of aberrant migration) and stem cell theory (transformed embryonic stem (ES) cells). In order to comprehend the histogenesis, we revisit the origin, migration, and fate of the human PGCs, and their transformation processes to iGCT.

DISCUSSION

In "germ cell theory," transformation of ectopic PGCs to iGCT is complex and involves multiple transcription factors. Germinoma is derived from ectopic PGCs and is considered a prototype of all GCTs. Non-germinomatous germ cell tumors (NGGCTs) develop from more differentiated counterparts of embryonic and extra-embryonic tissues. However, there is a distinct genomic/epigenomic landscape between germinoma and NGGCT. ES cells transformed from ectopic PGCs through molecular dysregulation or de-differentiation may become the source of iGCT. "Stem cell theory" is transformation of endogenous ES cells or primitive neural stem cell to iGCTs. It supports histological diversity of NGGCTs because of ES cell's pluripotency. However, neural stem cells are abundantly present along the subependymal zone; therefore, it does not explain why iGCTs almost exclusively occur in pineal and HNA locations. Also, the vast difference of methylation status between germinoma and NGGCT makes it difficult to theorize all iGCTs derive from the common cellular linage.

CONCLUSION

Transformation of PGCs to ES cells is the most logical mechanism for histogenesis of iGCT. However, its detail remains an enigma and needs further investigations.

Multiple ectopic germinomas presenting as focal dystonia of fingers: a case report and literature review

BACKGROUND

Intracranial primary germinomas predominantly develop on or near the midline structure in children and young adults and are diagnosed by brain imaging and biopsy. However, if brain imaging and pathology show unusual findings, it becomes difficult to make an accurate diagnosis.

CASE REPORT

Herein, we report the case of a 14-year-old boy who presented with focal dystonia of the fingers as an initial symptom. Magnetic resonance imaging of the brain showed multifocal heterogeneous lesions with solid and cystic components involving the right frontal lobe, corpus callosum, left basal ganglia, and left corona radiata. A stereotactic biopsy of the right frontal lesion revealed several granulomatous areas with abundant inflammatory cells. After immunohistochemical staining, the patient was diagnosed with germinoma and treated with chemoradiotherapy according to the Korean Society for Pediatric Neuro-Oncology protocol. The patient has been in complete remission for five years.

CONCLUSION

Germinomas can develop in intracranial off-midline structures, with unusual clinical, radiological, and pathological presentations. It is important to include intracranial germinomas in the differential diagnosis of infiltrative parenchymal tumors, especially in children.

Brain and Spinal Tumors Originating from the Germ Line Cells

Primary central nervous system germ cell tumors (CNS GCTs) are part of the GCTs in children and adults. This tumor entity presents with geographic variation, age, and sex predilection. There are two age peaks of incidence distribution at the first few months of life and in adolescence. CNS GCTs are heterogeneous in histopathological subtypes, locations, and tumor marker (AFP, β-hCG) secretions. In the WHO CNS tumor classification, GCTS are classified as germinoma and nongerminomatous GCT (NGGCT) with different subtypes (including teratoma). Excluding mature teratoma, the remaining NGGCTs are malignant (NGMGCT). In teratoma, growing teratoma syndrome and teratoma with somatic-type malignancy should be highlighted. The common intracranial locations are pineal region, neurohypophysis (NH), bifocal pineal-NH, basal ganglia, and cerebral ventricle. Above 50% of intracranial GCTs (IGCTs) present obstructive hydrocephalus. Spinal tumors are rare. Age, locations, hydrocephalus, and serum/CSF titer of β-hCG correlate with clinical manifestations. Delayed diagnosis is common in tumors arising in neurohypophysis, bifocal, and basal ganglia resulting in the increasing of physical dysfunction and hormonal deficits. Staging work-up includes CSF cytology for tumor cells and contrast-enhanced MRI of brain and spine for macroscopic metastasis before treatment commences. The therapeutic approach of CNS GCTs integrates locations, histopathology, staging, tumor marker level, and therapeutic classification. Treatment strategies include surgical biopsy/excision, chemotherapy, radiotherapy (single or combination). Secreting tumors with consistent imaging may not require histopathological diagnosis. Primary germinomas are highly radiosensitive and the therapeutic aim is to maintain high survival rate using optimal radiotherapy regimen with/without chemotherapy combination. Primary NGNGCTs are less radiosensitive. The therapeutic aim is to increase survival utilizing more intensive chemotherapy and radiotherapy. The negative prognostic factors are residue disease at the end of treatment and serum or CSF AFP level >1000 ng/mL at diagnosis. In refractory or recurrent NMGGCTs, besides high-dose chemotherapy, new therapy is necessary. Molecular profiling and analysis help for translational research. Survivors of pediatric brain tumors frequently experience cancer-related cognitive dysfunction, physical disability, pituitary hormone deficiency, and other CNS complications after cranial radiotherapy. Continuous surveillance and assessment may lead to improvements in treatment protocols, transdisciplinary interventions, after-treatment rehabilitation, and quality of life.

Diencephalic syndrome in a female child due to intracranial germinoma: a case report

INTRODUCTION

Diencephalic syndrome (DS) is a rare syndrome with failure to thrive (FTT) as the primary manifestation, which is often associated with astrocytoma or glioma and rarely caused by germinoma. To our knowledge, there are no reports of female patients presenting with DS secondary to germinoma.

CASE REPORT

we report a case (an 11-year-old girl) of diencephalic syndrome presenting with FTT. She was diagnosed with severe malnutrition in the local hospital two years before admission and still did not show normal development after long-term nutritional support. Finally, after ruling out increased metabolism, inadequate caloric intake, and nutrient absorption, intracranial MRI showed a space-occupying lesion in the suprasellar cisterna-hypothalamus area. After excluding other causes of FTT, a biopsy was performed for pathological examination and demonstrated a germinoma. An excellent therapeutic effect was achieved during the three-month follow-up after radiotherapy.

CONCLUSION

This case reminds us that intracranial tumors should be considered an indispensable etiology for patients with suspicious FTT, and early diagnosis and intervention may achieve a good prognosis.

Socio-behavioral dysfunction in disorders of hypothalamic-pituitary involvement: The potential role of disease-induced oxytocin and vasopressin signaling deficits

Disorders involving hypothalamic and pituitary (HPIT) structures-including craniopharyngioma, Langerhans cell histiocytosis, and intracranial germ cell tumors-can disrupt brain and endocrine function. An area of emerging clinical concern in patients with these disorders is the co-occurring socio-behavioral dysfunction that persists after standard hormone replacement therapy. Although the two neuropeptides most implicated in mammalian social functioning (oxytocin and arginine vasopressin) are of hypothalamic origin, little is known about how disease-induced damage to HPIT structures may disrupt neuropeptide signaling and, in turn, impact patients' socio-behavioral functioning. Here we provide a clinical primer on disorders of HPIT involvement and a review of neuropeptide signaling and socio-behavioral functioning in relevant animal models and patient populations. This collective evidence suggests that neuropeptide signaling disruptions contribute to socio-behavioral deficits experienced by patients with disorders of HPIT involvement. A better understanding of the biological underpinnings of patients' socio-behavioral symptoms is now needed to enable the development of the first targeted pharmacological strategies by which to manage patients' socio-behavioral dysfunction.

Value of C-11 methionine PET/CT in patients with intracranial germinoma

Purpose

The purpose of this study was to investigate the value of C-11 methionine (MET) positron emission tomography (PET)/computed tomography (CT) in patients with intracranial germinoma (IG).

Material and methods

We conducted a retrospective analysis of 21 consecutive patients with pathologically confirmed IGs and eight patients with intracranial non-germinomas (INGs) located in a similar region. Clinical characteristics, imaging findings, and tumor markers such as α-fetoprotein (AFP) and β-human chorionic gonadotropin (HCG) were used as clinical variables. Maximum standardized uptake value (SUVmax), tumor-to-normal tissue (T/N) ratio, and visual scoring of tumor were used as MET PET parameters.

Results

All IGs were well visualized on MET PET with a three-grade visual scoring system. In addition, SUVmax of IGs was higher than that of INGs (P = 0.005). Pre-treatment (Pre-Tx) T/N ratio was significantly correlated with pre-Tx serum HCG (P = 0.031). Moreover, MET PET parameters showed significant associations with tumor location, sex, KRAS variant, and symptoms.

Conclusion

MET PET/CT could be a useful diagnostic tool in patients suspected of having IGs. In addition, the MET avidity of tumor is a potential surrogate biomarker of HCG, which has been used as a diagnostic marker for IGs. Tumor MET parameters also had significant differences according to tumor locations, sex, symptoms, and KRAS mutation. However, MET avidity of tumors had no significant prognostic value.

A GIANT GERMINOMA MIMICS HIGH-GRADE GLIOMA: A RARE FORM OF THALAMIC REGION TUMOR

A fourteen-year-old boy initially presented with weakness in the right extremity, worsening in the last three months with stiffness and convulsions in his right extremity. Magnetic resonance imaging of the brain revealed an intra-axial tumor measuring 8.3x7.3x6.8 cm, leading to obstructive hydrocephalus. The patient's condition suddenly worsened with decreased consciousness, and then emergency surgery was performed for tumor resection and external ventricular drainage before switching to a ventriculoperitoneal shunt on the fifth day after surgery. Histopathological examination revealed a germinoma, which is rare in the thalamic region. The patient responded well to radiation therapy after surgery. Ectopic GCT may be difficult to differentiate on radiological examination alone. The current case was initially diagnosed as a high-grade glioma based on radiological findings. A definite diagnosis can be made only after a histopathological examination, which requires a tissue sample. Therefore, many tumors are surgically excised for biopsy purposes A good preoperative examination is very important to determine the approach to patient management. Furthermore, radiotherapy is mandatory for germinoma because of its radiosensitivity.

Neuroimaging of paediatric pineal, sellar and suprasellar tumours: a guide to differential diagnosis

INTRODUCTION

Pineal, sellar and suprasellar tumours in children comprise a wide range of diseases with different biological behaviours and clinical management. Neuroimaging plays a critical role in the diagnosis, treatment planning and follow up of these patients, but imaging interpretation can prove challenging due to the significant overlap in radiological features.

MATERIALS AND METHOD

A review of the literature was performed by undertaking a search of the MEDLINE and EMBASE databases for appropriate MeSH terminology. Identified abstracts were screened for inclusion and articles meeting the objectives of the review were included.

RESULTS AND CONCLUSION

In this article, we review radiological appearances of common and uncommon pineal, sellar and suprasellar tumours occurring in the paediatric population. We discuss the importance of anatomical localization, clinical information and cerebrospinal fluid tumour markers, and propose a practical approach to differential diagnosis. Lastly, we discuss future directions and prospective new imaging strategies to support state-of-the-art patient care.

A pragmatic diagnostic approach to primary intracranial germ cell tumors and their treatment outcomes

Background: Primary intracranial germ cell tumors (ICGCT) are often diagnosed with tumor markers and imaging, which may avoid the need for a biopsy. An intracranial germ cell tumor with mild elevation of markers is seldom stratified as a distinct entity. Methods: Fifty-nine patients were stratified into three groups: pure germinoma (PG), secreting germinoma (SG) and non-germinomatous germ cell tumors (NGGCTs). Results: At 5 years, progression-free survival and overall survival of the three groups (PG vs SG vs NGGCT) were 91% versus 81% versus 59%, and 100% versus 82% versus 68%, respectively. There was no statistically significant difference in outcome among histologically and clinically diagnosed germinomas. Conclusion: A criterion for clinical diagnosis when a biopsy is not feasible is elucidated, and comparable outcomes were demonstrated with histologically diagnosed germinomas.

Brain Microstructural Changes Associated With Neurocognitive Outcome in Intracranial Germ Cell Tumor Survivors

Background

Childhood intracranial germ cell tumor (GCT) survivors are prone to radiotherapy-related neurotoxicity, which can lead to neurocognitive dysfunctions. Diffusion kurtosis imaging (DKI) is a diffusion MRI technique that is sensitive to brain microstructural changes. This study aimed to investigate the association between DKI metrics versus cognitive and functional outcomes of childhood intracranial GCT survivors.

Methods

DKI was performed on childhood intracranial GCT survivors (n = 20) who had received cranial radiotherapy, and age and gender-matched healthy control subjects (n = 14). Neurocognitive assessment was performed using the Hong Kong Wechsler Intelligence Scales, and functional assessment was performed using the Lansky/Karnofsky performance scales (KPS). Survivors and healthy controls were compared using mixed effects model. Multiple regression analyses were performed to determine the effects of microstructural brain changes of the whole brain as well as the association between IQ and Karnofsky scores and the thereof.

Results

The mean Intelligence Quotient (IQ) of GCT survivors was 91.7 (95% CI 84.5 – 98.8), which was below the age-specific normative expected mean IQ (P = 0.013). The mean KPS score of GCT survivors was 85.5, which was significantly lower than that of controls (P < 0.001). Cognitive impairments were significantly associated with the presence of microstructural changes in white and grey matter, whereas functional impairments were mostly associated with microstructural changes in white matter. There were significant correlations between IQ versus the mean diffusivity (MD) and mean kurtosis (MK) of specific white matter regions. The IQ scores were negatively correlated with the MD of extensive grey matter regions.

Conclusion

Our study identified vulnerable brain regions whose microstructural changes in white and grey matter were significantly associated with impaired cognitive and physical functioning in survivors of pediatric intracranial GCT.

Gliomas, germ cell tumors, and craniopharyngioma

This report summarizes the current multimodality treatment approaches for children with low- and high-grade gliomas, germinoma, and nongerminomatous germ cell tumors, and craniopharyngiomas used in the Children's Oncology Group (COG) and the International Society of Pediatric Oncology (SIOP). Treatment recommendations are provided in the context of historical approaches regarding the roles of surgery, radiation, and chemotherapy. Future research strategies for these tumors in both COG and SIOP are also discussed.

Sacrococcygeal Teratoma : A Tumor at the Center of Embryogenesis

Sacrococcygeal teratoma (SCT) is an extragonadal germ cell tumor (GCT) that develops in the fetal and neonatal periods. SCT is a type I GCT in which only teratoma and yolk sac tumors arise from extragonadal sites. SCT is the most common type I GCT and is believed to originate through epigenetic reprogramming of early primordial germ cells migrating from the yolk sac to the gonadal ridges. Fetal SCT diagnosed in utero presents many obstetrical problems. For high-risk fetuses, fetal interventions (devascularization and debulking) are under development. Most patients with SCT are operated on after birth. Complete surgical resection is the key for tumor control, and the anatomical location of the tumor determines the surgical approaches. Incomplete resection and malignant histology are risk factors for recurrence. Approximately 10-15% of patients have a tumor recurrence, which is frequently of malignant histology. Long-term surveillance with monitoring of serum alpha fetoprotein and magnetic resonance imaging is required. Survivors of SCT may suffer anorectal, urological, and sexual sequelae later in their life, and comprehensive evaluation and care are required.

Multimodality treatment for Central Nervous System Germ Cell Tumors: Disease spectrum and management strategies - A tertiary care center experience from India

OBJECTIVE

Intracranial germ cell tumors (GCTs) are relatively rare neoplasms, representing 2-3 % of paediatric brain tumors in Western countries and 8-15 % in East Asia. Here, we discuss the clinical features and treatment outcomes in patients with central nervous system (CNS) GCTs treated at our institute.

METHODS

Medical records of all primary CNS GCT patients were retrieved retrospectively from 2007 to 2019. Demographic, clinical, treatment and follow up details were entered in a predesigned proforma. Overall survival (OS) and progression-free survival was computed using Kaplan-Meier method and Log-Rank test. Effect of various prognostic factors on survival outcomes was assessed by univariate and multivariate analysis.

RESULTS

A total of 28 CNS GCT patients were included in this analysis. Median age at presentation was 17 years (range, 7-45 years) with a male to female ratio of 1.8:1. Pineal region was the commonest location, encountered in 15 patients (53.6 %). Pure germinoma was the most frequent histology observed, seen in 19 patients (67.9 %). Male gender and germinoma histology were highly associated with pineal location (p = 0.043 and p = 0.052, respectively). Fourteen patients underwent surgical intervention and nine patients underwent biopsy for diagnostic purpose or to relieve the obstructive symptoms. Only 23 patients (82.1 %) received chemotherapy. However, all patients received radiotherapy (Craniospinal irradiation/whole brain radiotherapy/whole ventricular radiotherapy/ or local radiotherapy). After a median follow-up of 53 months (range, 7-150), 23 patients (82.1 %) were alive. OS was significantly affected by histology (89 % in germinoma vs. 60 % in non-germinomatous, p = 0.054) and location (93 % in pineal region vs. 64.2 % in other location, p = 0.042). Age, gender and surgery did not have any impact on the survival outcomes.

CONCLUSION

CNS GCTs are relatively rare and heterogeneous neoplasms commonly seen in pineal and suprasellar locations. A combination of chemotherapy and radiotherapy had shown excellent outcomes.

Multiple Tumor-Associated Intracranial Aneurysms Adjacent to a Suprasellar Germ Cell Tumor: Case Report and Review of Literature

INTRODUCTION

Tumor-associated intracranial aneurysms are rare and not well understood.

CASE PRESENTATION

We describe a 4-year-old female with multiple intracranial aneurysms intimately associated with a suprasellar germ cell tumor (GCT). We provide the clinical history, medical, and surgical treatment course, as well as a comprehensive and concise synthesis of the literature on tumor-associated aneurysms.

DISCUSSION

We discuss mechanisms for aneurysm formation with relevance to the current case, including cellular and paracrine signaling pertinent to suprasellar GCTs and possible molecular pathways involved. We review the complex multidisciplinary treatment required for complex tumor and cerebrovascular interactions.

Cerebrospinal fluid ctDNA and metabolites are informative biomarkers for the evaluation of CNS germ cell tumors

Serum and cerebrospinal fluid (CSF) levels of α-fetoprotein and β-subunit of human chorionic gonadotropin are used as biomarkers for the management of central nervous system (CNS) germ cell tumors (GCTs). However, additional discriminating biomarkers are required. Especially, biomarkers to differentiate non-germinomatous germ cell tumors (NGGCTs) from germinomas are critical, as these have a distinct prognosis. We investigated CSF samples from 12 patients with CNS-GCT patients (8 germinomas and 4 NGGCTs). We analyzed circulating tumor DNA (ctDNA) in CSF to detect mutated genes. We also used liquid chromatography-mass spectrometry to characterize metabolites in CSF. We detected KIT and/or NRAS mutation, known as frequently mutated genes in GCTs, in 3/12 (25%) patients. We also found significant differences in the abundance of 15 metabolites between control and GCT, with unsupervised hierarchical clustering analysis. Metabolites related to the TCA cycle were increased in GCTs. Urea, ornithine, and short-chain acylcarnitines were decreased in GCTs. Moreover, we also detected several metabolites (e.g., betaine, guanidine acetic acid, and 2-aminoheptanoic acid) that displayed significant differences in abundance in patients with germinomas and NGGCTs. Our results suggest that ctDNA and metabolites in CSF can serve as novel biomarkers for CNS-GCTs and can be useful to differentiate germinomas from NGGCTs.

Clinical experience of growth hormone replacement for pediatric intracranial germ cell tumor

PURPOSE

Intracranial germ cell tumors (IGCTs) account for 8-15% of brain tumors in children in Eastern Asia and typically occur at the age of puberty. Recently, adjuvant therapy has been modified to ameliorate post-treatment complications such as cognitive dysfunction, in patients with IGCT. However, endocrine problems remain to be resolved. There is reluctance to use growth hormone (GH) at an early stage after treatment for IGCT because of the risk of tumor recurrence; however, GH replacement must be administered before the onset of puberty in children with short stature. There is little guidance on this issue due to a lack of literature on the risks of GH replacement therapy in patients with IGCT. This study aimed to evaluate the safety of GH replacement.

METHODS

In this retrospective study, 6 patients with IGCT who were under the age of 18 years when they started GH replacement therapy were reviewed. Histopathological analysis and/or analysis of tumor markers was used to confirm a diagnosis.

RESULTS

All six cases who underwent GH replacement therapy showed no recurrence. GH replacement therapy was administered in 5 patients for short stature and all achieved a height within ± 2.0 standard deviation.

CONCLUSION

GH replacement for children with IGCT was safe in our case series. Placental alkaline phosphatase levels in cerebrospinal fluid can be used to facilitate the decision on when to initiate GH replacement.

Bifocal germinoma in a patient with 16p11.2 microdeletion syndrome

Intracranial germinomas are rare tumors affecting mostly patients at young age. Therefore, molecular data on its etiopathogenesis are scarce. We present a clinical case of a male patient of 25 years with an intracranial germinoma and a 16p11.2 microdeletion. His initial complaints were related to obesity, loss of facial hair and polydipsia. He also had a history of social-interaction difficulties during childhood. His blood tests were consistent with hypogonadotropic hypogonadism and secondary adrenal insufficiency, and he had been previously diagnosed with hypothyroidism. He also presented with polyuria and polydipsia and the water deprivation test confirmed the diagnosis of diabetes insipidus. His sellar magnetic resonance imaging (MRI) showed two lesions: one located in the pineal gland and other in the suprasellar region, both with characteristics suggestive of germinoma. Chromosomal microarray analysis was performed due to the association of obesity with social disability, and the result identified a 604 kb 16p11.2 microdeletion. The surgical biopsy confirmed the histological diagnosis of a germinoma. Pharmacological treatment with testosterone, hydrocortisone and desmopressin was started, and the patient underwent radiotherapy (40 Gy divided in 25 fractions). Three months after radiotherapy, a significant decrease in suprasellar and pineal lesions without improvement in pituitary hormonal deficiencies was observed. The patient is currently under follow-up. To the best of our knowledge, we describe the first germinoma in a patient with a 16p11.2 deletion syndrome, raising the question about the impact of this genetic alteration on tumorigenesis and highlighting the need of molecular analysis of germ cell tumors as only little is known about their genetic background. Learning points: Central nervous system germ cell tumors (CNSGTs) are rare intracranial tumors that affect mainly young male patients. They are typically located in the pineal and suprasellar regions and patients frequently present with symptoms of hypopituitarism. The molecular pathology of CNSGTs is unknown, but it has been associated with gain of function of the KIT gene, isochromosome 12p amplification and a low DNA methylation. Germinoma is a radiosensitive tumor whose diagnosis depends on imaging, tumor marker detection, surgical biopsy and cerebrospinal fluid cytology. 16p11.2 microdeletion syndrome is phenotypically characterized by developmental delay, intellectual disability and autism spectrum disorders. Seminoma, cholesteatoma, desmoid tumor, leiomyoma and Wilms tumor have been described in a few patients with 16p11.2 deletion. Bifocal germinoma was identified in this patient with a 16p11.2 microdeletion syndrome, which represents a putative new association not previously reported in the literature.