Paediatric germ cell tumours of the central nervous system: Results and experience from a tertiary-referral paediatric institution in Australia

Evolution of Surgical Management of Pineal Region Tumors in the Pediatric Population: A 17-Year Experience at a Single Institution

INTRODUCTION

Pineal region tumors have historically been challenging to treat. Advances in surgical techniques have led to significant changes in care and outcomes for these patients, and this is well demonstrated by our single institution's experience over a 17-year-period in which the evolution of diagnosis, treatment, and outcomes of pineal tumors in pediatric patients will be outlined.

METHODS

We retrospectively collected data on all pediatric patients with pineal region lesions treated with surgery at Children's National Hospital (CNH) from 2005 to 2021. Variables analyzed included presenting symptoms, presence of hydrocephalus, diagnostic and surgical approach, pathology, and adverse events, among others. IRB approval was obtained (IRB: STUDY00000009), and consent was waived due to minimal risk to patients included.

RESULTS

A total of 43 pediatric patients with pineal region tumors were treated during a 17-year period. Most tumors in our series were germinomas (n = 13, 29.5%) followed by pineoblastomas (n = 10, 22.7%). Twenty seven of the 43 patients (62.8%) in our series received a biopsy to establish diagnosis, and 44.4% went on to have surgery for resection. The most common open approach was posterior interhemispheric (PIH, transcallosal) - used for 59.3% of the patients. Gross total resection was achieved in 50%; recurrence occurred in 20.9% and mortality in 11% over a median follow-up of 47 months. Endoscopic third ventriculostomy (ETV) was employed to treat hydrocephalus in 26 of the 38 patients (68.4%) and was significantly more likely to be performed from 2011 to 2021. Most (73%) of the patients who received an ETV also underwent a concurrent endoscopic biopsy. No difference was found in recurrence rate or mortality in patients who underwent resection compared to those who did not, but complications were more frequent with resection. There was disagreement between frozen and final pathology in 18.4% of biopsies.

CONCLUSION

This series describes the evolution of surgical approaches and outcomes over a 17-year-period at a single institution. Complication rates were higher with open resection, reinforcing the safety of pursuing endoscopic biopsy as an initial approach. The most significant changes occurred in the preferential use of ETVs over ventriculoperitoneal shunts. Though there has been a significant evolution in our understanding of and treatment for these tumors, in our series, the outcomes for these patients have not significantly changed over that time.

Clinicopathological spectrum of central nervous system germ cell tumors: A single-institution retrospective study

CONTEXT

Central nervous system germ cell tumors (CNSGCTs) though rare is the second most common extragonadal site for GCTs.

AIMS

To determine the clinicopathological features of CNSGCTs diagnosed at our center.

SETTINGS AND DESIGN

A retrospective study of all histologically diagnosed CNSGCTs, during 2006-2019.

MATERIALS AND METHODS

The patients' data were retrieved from the hospital information systems and analyzed.

STATISTICAL ANALYSIS

Data on categorical variables were analyzed as percentages, and data on continuous variables calculated as mean. Chi-square test or Fisher's exact test was used to study association between variables.

RESULTS

Of the total 34 cases with CNSGCT, age ranged from 1 to 27 years, majority in the second decade (19/34; 56%). Male: female (M: F) ratio was 1.6:1. Single site involvement was seen in 27 cases (27/34; 79%), whereas seven (7/34; 21%) showed bi/multifocal involvement. Among the unifocal cases, common sites involved were suprasellar (12/27; 44.4%), closely followed by the pineal (10/27; 37%). All multifocal tumors affected suprasellar compartment, being bifocal with pineal in four cases. A male gender predilection was noted among pineal region (9/10;90%) and multifocal tumors (5/7;71%). Germinoma was the commonest subtype (21/34; 61.8%) with male gender predilection (17/21; 81%) (M: F =4.3:1), with female predilection seen among mixed GCTs (MGCTs) (8/10; 80%) (M: F =1:4) and suprasellar location (M: F =1:2). Serum tumor markers (25 cases) and CSF markers (7 cases) were concordant with histology in all, except two cases.

CONCLUSION

Though histology and immunohistochemistry were diagnostic, correlation between serum and/or CSF marker was essential to rule out GCT component(s) that may be missed on biopsy due to sampling error.

The role of neoadjuvant chemotherapy in the management of metastatic central nervous system germinoma: A meta-analysis

BACKGROUND

The role of neoadjuvant chemotherapy in treating patients with metastatic central nervous system (CNS) germinoma is controversial.

METHODS

We compared the relapse-free survival (RFS) of different treatment modalities by performing a meta-analysis using published data. We summarized all data using standard descriptive statistics. We used the Kaplan-Meier method to estimate RFS and their corresponding 95% confidence intervals (CIs). We used the log-rank test for the comparison of survival functions.

RESULTS

We identified 97 patients with a median age at presentation of 15 years (range: 7-38). Sites of metastasis were cerebrospinal fluid (CSF) disease only (n = 12), brain parenchyma (n = 18), spinal cord (n = 9), ventricular and CSF (n = 10), ventricular only (n = 31), and other (n = 17). The 3-year RFS among patients who received any form of radiotherapy was 89% (95% CI: 83-96) compared with 0% for patients who received a chemotherapy-only regimen (p = .001). Five-year RFS among patients who received craniospinal irradiation (CSI) was 92% (95% CI: 84-100) compared with 76.4% (95% CI: 63-90) in the non-CSI group (with or without neoadjuvant chemotherapy) (p = .014). Five-year RFS of patients who received CSI less than 24 Gy with neoadjuvant chemotherapy was 100% compared with 92% (95% CI: 83-100) CSI dose greater than or equal to 24 Gy alone (p = .3).

CONCLUSIONS

Our analysis does not support avoiding spinal irradiation among patients with radiographic metastatic CNS germinoma. Future studies are needed to confirm whether neoadjuvant chemotherapy will allow a reduction of irradiation dose without compromising survival.

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.

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.

Comparison on epidemiology, tumor location, histology, and prognosis of intracranial germ cell tumors between Mayo Clinic and Japanese consortium cohorts

OBJECTIVE

Central nervous system (CNS) germ cell tumors (GCTs) are rare malignant neoplasms that arise predominantly in adolescents and young adults. CNS GCTs demonstrate characteristic trends in national associations, with implications for both tumor incidence and genetics. Although the incidence of CNS GCTs is markedly higher in East Asia than Western countries, direct comparative analyses between these CNS GCT populations are limited.

METHODS

In Japan, to facilitate the genomic analyses of CNS GCTs, the Intracranial Germ Cell Tumor Genome Analysis Consortium was established in 2011, and more than 200 cases of GCTs are available for both tumor tissue and clinical data, which is organized by the National Cancer Center (NCC) Japan. At the Mayo Clinic, there have been 98 cases of intracranial GCTs treated by the Department of Neurologic Surgery since 1988. In this paper, the authors compared the epidemiology, clinical presentation including location and histology, and prognosis between cases treated in the US and Japan.

RESULTS

There was no significant difference in age and sex distributions between the databases. However, there was a significant difference in the tumor locations; specifically, the frequency of basal ganglia was higher in the NCC database compared with the Mayo Clinic (8.4% vs 0%, p = 0.008), and bifocal location (neurohypophysis and pineal gland) was higher at the Mayo Clinic than at the NCC (18.8% vs 5.8%, p = 0.002). There was no difference in histological subdivisions between the databases. There was no difference in progression-free survival (PFS) and overall survival (OS) of germinoma cases and OS of nongerminomatous GCT (NGGCT) cases treated with chemotherapy and radiation therapy covering whole ventricles. However, PFS of NGGCTs differed significantly, and was better in the NCC cohorts (p = 0.04).

CONCLUSIONS

There appears to be a differential distribution of GCTs by neuroanatomical location between major geographic and national groups. Further study is warranted to better characterize any underlying genomic, epigenetic, or environmental factors that may be driving the phenotypic differences.

Prognostic factors related to intratumoral hemorrhage in pediatric intracranial germ cell tumors

BACKGROUND

Certain types of pediatric intracranial germ cell tumors (PIGCTs) are prone to intratumoral hemorrhaging (TH) and associated with poor survival outcome. However, the impact of TH on the functional prognosis of patients with PIGCTs has not been well studied. This study aimed to evaluate the clinical and MR findings in PIGCT patients with TH to identify the factors related to patient survival and functional outcome.

METHODS

This study included 17 patients diagnosed with PIGCT and TH between 2002 and 2016 and evaluated TH-associated clinical and MR findings. The modified Rankin scale (mRS) was used to evaluate functional outcome, which was poor when mRS ≧ 3. The volumes of hematomas and tumors were manually tracked within each brain magnetic resonance imaging slice.

RESULTS

Among the 17 patients, 6 (35.3%) died and 9 (52.9%) had poor functional outcome. Regarding the functional outcome, the mean hematoma volume to tumor volume ratio (HTVR) was 8.5 ± 3.9% in the favorable outcome group and 42.3 ± 27.8% in the poor outcome group (p = 0.001). For the survival outcome, the mean HTVR was 15.7 ± 16.1% in the living group and 46.0 ± 31.5% in the deceased group (p = 0.016). The cutoff point of the receiver operating characteristics curve for HTVR to predict death and poor functional outcome was 19.27% and 16.8%, respectively.

CONCLUSION

Our study demonstrated that patients with larger HTVR had significantly worse functional and survival outcomes than those with smaller HTVR. We suggest that early and aggressive treatment for PIGCTs in patients with large HTVR can improve their long-term prognosis.

A Rare Localized Pituitary Stalk Germinoma Presenting in the Third Decade

We report the case of a 34-year-old male Hispanic patient who presented with an 8-month history of polyuria and decreased libido. An evaluation revealed hypopituitarism, central diabetes insipidus, and a pituitary stalk lesion. No evidence of a neoplasm or an inflammatory/infiltrative disease was found. We treated the patient conservatively with steroid therapy. However, as a result of disease progression, transsphenoidal surgery was performed to obtain tissue for a pathological analysis. Histopathology revealed an intrasellar germinoma, confirmed by immunochemistry. Due to localized disease, radiotherapy was initiated and clinical improvement was noted. This case emphasizes the importance of histopathological analysis; for many physicians, the presentation of a pituitary stalk lesion in a young male adult creates a clinical conundrum. Although the most common etiologies are an inflammatory or secondary neoplasm, the possible presence of an intrasellar neoplasm should not be ruled out. In many cases, imaging characteristics and tumor markers may aid in the diagnosis without the need of an aggressive diagnostic approach. However, in this case, histopathological analysis was the only way to make a correct diagnosis and provide adequate treatment for the patient.

Second-Look Surgery for Intracranial Germ Cell Tumors

BACKGROUND:

The role of second-look surgery in intracranial germ cell tumors (GCTs) needs to be reviewed.

OBJECTIVE:

To present our experience of second-look surgery in patients with intracranial GCTs who showed less than complete response despite normalizing or decreasing tumor markers after chemotherapy.

METHODS:

Retrospective review of 7 patients who underwent second-look surgery for an intracranial GCT was performed.

RESULTS:

Of 23 consecutive patients with newly diagnosed intracranial GCTs treated between August 2003 and August 2013, 7 patients (30%) underwent second-look surgery. The mean age was 9.4 years. The initial diagnoses were mixed germ cell tumor in 5 and immature teratoma in 2. Second-look surgery was performed after 1 to 3 courses of chemotherapy. Magnetic resonance imaging at the surgery demonstrated increasing residual tumor in 4 and stable residual tumor in 3. Tumor markers were normalized in 5 and nearly normalized in 2. Gross total resection was achieved in all patients. Histopathology at second-look surgery revealed mature teratoma in 5, fibrosis with atypical cells in 1, and fibrosis in 1. All patients subsequently underwent additional chemoradiation therapy according to the initial diagnosis. All patients are alive with no evidence of recurrence, with a mean follow-up of 48 months.

CONCLUSION:

Second-look surgery plays an important role in the treatment of intracranial GCTs. Surgery may be encouraged at a relatively early phase after chemotherapy when the residual tumor increases or does not change size despite normalized or nearly normalized tumor markers in order to achieve complete resection and improve outcome.

Secondary nocturnal enuresis related to central diabetes insipidus as an early manifestation of intracranial germinomatous germ cell tumors in a series of male youngsters

Nocturnal enuresis is a common symptom in children. It is usually attributed to benign causes and diagnostic evaluation is not carried out. We report three male young patients initially presenting with short stature and nocturnal enuresis, related to diabetes insipidus, caused by intracranial germinomatous germ cell tumors. In all three cases, water deprivation tests confirmed diabetes insipidus. Extensive endocrinological investigation also showed further hormone deficiencies. Magnetic resonance imaging of the brain revealed the presence of a central nervous system lesion and histology confirmed the final diagnosis. Surgery, radiation with or without chemotherapy was conducted and the patients were treated with hormone replacement therapies. The patients after a long follow-up were free of disease. We present these cases to alert clinicians to bear in mind that the presence of an intracranial germinomatous germ cell tumor should at least be considered in a child presenting with bed wetting, especially if additional symptoms and signs, including late onset puberty and growth delay or morning hypernatremia, may coexist.

Incidence of intracranial germ cell tumors by race in the United States, 1992-2010

Little is known about the etiology of intracranial germ cell tumors (iGCTs), although international incidence data suggest that the highest incidence rates occur in Asian countries. In this analysis, we used 1992-2010 data from the National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) Program to determine whether rates of iGCT were also high in Asian/Pacific Islanders living in the United States. Frequencies, incidence rates and survival rates were evaluated for the entire cohort and for demographic subgroups based on sex, age category (0-9 and 10-29 years), race (white, black, and Asian/Pacific Islander), and tumor location (pineal gland vs. other) as sample size permitted. Analyses were conducted using SEER*Stat 8.1.2. We observed a significantly higher incidence rate of iGCT in Asian/Pacific Islanders compared with whites (RR = 2.05, 95 % CI 1.57-2.64, RR = 3.04, 95 % CI 1.75-5.12 for males and females, respectively) in the 10-29 year age group. This difference was observed for tumors located both in the pineal gland and for tumors in other locations. Five-year relative survival differed by demographic and tumor characteristics, although these differences were not observed in comparisons limited to cases treated with radiation. Increased incidence rates of iGCT in individuals of Asian descent in the SEER registry are in agreement with data from the International Agency for Research on Cancer, where Japan and Singapore were among the countries with highest incidence. The increased incidence in individuals of Asian ancestry in the United States suggests that underlying genetic susceptibility may play a role in the etiology of iGCT.

Clinical analysis on 33 patients with hypothalamic syndrome in Chinese children

AIM

To investigate the etiology and clinical characteristics of hypothalamic syndrome in Chinese children.

METHODS

Thirty-three cases of hypothalamic syndrome were analyzed for etiology, initial symptoms, and clinical characteristics.

RESULTS

All of the 33 patients manifested symptoms of hypothalamic dysfunction and disorders of the hypothalamus-hypophysis-target gland axis. Fourteen patients were diagnosed with an intracranial tumor by magnetic resonance imaging (MRI) examination, four patients had postoperative intracranial tumors, one had received radiotherapy for suprasellar germinoma, one was hypothalamic-pituitary dysplasia, one had a history of viral encephalitis, and in 12 patients, the cause was unknown. The most common presenting symptoms were polydipsia/polyuria and eating disorders.

CONCLUSION

Intracranial tumor is an important cause of hypothalamic syndrome in children, with germinoma the most common. Polydipsia, polyuria, and eating disorders are typical presenting symptoms. Long-term follow-up is needed for patients presenting with central diabetes insipidus, eating disorders or hypothalamic syndrome of unknown etiology. In addition, periodic pituitary MRI scanning is necessary to find potential intracranial tumors that may arise at any time.

The "extended" endoscopic endonasal approach for the removal of a mixed intrasuprasellar germinoma: Technical case report

Background:

Intracranial germ cell tumors (GCTs) represent less than 5% of pediatric brain tumors. Neurosurgical treatment remains essential in the management of patients with intracranial nongerminomatous GCT.

Case Description:

A 12-year-old girl presented with clinical features of neurohypophyseal dysfunction and rapidly progressive visual worsening. Magnetic resonance imaging (MRI) showed a lesion arising from the sella with a significant suprasellar component, compressing the optic chiasm and extending into the third ventricle. The tumor was removed via an endoscopic endonasal transtuberculum-transplanum approach and the histology revealed a mixed germinoma. In the postoperative course, a conspicuous improvement of visual function was observed; an early postoperative MRI showed near-total removal of the lesion. The patient was referred to pediatric oncologist for the adjunctive chemotherapy and radiotherapy.

Conclusions:

The management of primary intracranial sellar and suprasellar germinomas still remains controversial. With this report we highlighted another possible surgical option among therapeutic strategies for these highly malignant tumors.