Neurosurgical management of paediatric germ cell tumours of the central nervous system--a multi-disciplinary team approach for the new millennium

Secreting Germ Cell Tumors of the Central Nervous System: A Long-Term Follow-up Experience

INTRODUCTION

Due to the rarity of nongerminomatous germ cell tumors (NGGCT) with non-standard treatment as yet, we report retrospectively our 30 year experience with chemotherapy followed by craniospinal irradiation (CSI), plus a boost of whole ventricular irradiation (WVI)/tumor bed (TB), tailored to pre-radiation chemotherapy response.

METHODS

Between 1988 and 2016, 28 patients received four cycles of PEB (cisplatin/etoposide/bleomycin), then CSI, and two further PEB cycles. Between 1988 and1994, CSI was 25.5 Gy for patients in complete remission (CR), 30 Gy if in partial remission (PR) or metastatic, with a boost to TB up to 45-54 Gy. In the period of 1995-2010, the boost included WVI and any extra-ventricular tumor sites up to 45 Gy. After 2010, CSI was reduced to 25.5 Gy for all non-metastatic patients, and a boost was given only to TB up to 40.5/45.5 Gy, depending on patients' CR/PR status. After 2003, patients with alfafetoprotein (αFP) > 1000 ng/mL received intensified treatment, also including autologous stem cell transplantation.

RESULTS

Among 28 patients (23 males; median age 12 years, 6 metastatic), 25 responded to PEB, and three progressed (PD) after one to four cycles; 26 received radiotherapy obtaining 13 CR, 7 PR and 5 stable disease (SD), 1 PD; 6 (21%) died (5 for disease, 1 for pneumonia while in CR). Five-year overall survival (OS) and progression-free survival (PFS) were both 81%; 10 year OS and PFS 81% and 76%, respectively (median follow-up 11 years).

CONCLUSIONS

Survival for children with NGGCT, independently from disease extent, was encouraging. Further studies should elucidate which patients could benefit from reduced volume and dose irradiation.

Clinical utility of circulating miR-371a-3p for the management of patients with intracranial malignant germ cell tumors

Background

The current biomarkers alpha-fetoprotein (AFP) and human chorionic gonadotropin (HCG) have limited sensitivity/specificity for diagnosing malignant germ cell tumors (GCTs) and "marker-negative" patients require histological confirmation for diagnosis. However, GCTs at intracranial sites are surgically relatively inaccessible and biopsy carries risks. MicroRNAs from the miR-371~373 and miR-302/367 clusters are over-expressed in all malignant GCTs and, in particular, miR-371a-3p shows elevated serum levels at diagnosis for testicular disease.

Methods

Using our robust preamplified qRT-PCR methodology, we quantified miR-371a-3p levels in serum and cerebrospinal fluid (CSF) in a series of 4 representative clinical cases, 3 with intracranial malignant GCT and 1 with Langerhans cell histiocytosis (LCH), compared with appropriate control cases.

Results

Serum and/or CSF miR-371a-3p levels distinguished those with intracranial malignant GCTs from LCH and, if known in real time, could have helped clinical management. The benefits would have included (1) the only confirmatory evidence of an intracranial malignant GCT in 1 case, supporting clinical decision making; (2) early detection of intracranial malignant GCT in another, where an elevated CSF miR-371a-3p level preceded the histologically confirmed diagnosis by 2 years; and (3) confirmation of an intracranial malignant GCT relapse with an elevated serum miR-371a-3p level, where serum and CSF AFP and HCG levels were below thresholds for such a diagnosis.

Conclusions

This series highlights the potential for microRNA quantification to assist the noninvasive diagnosis, prognostication, and management for patients with intracranial malignant GCTs. Serum and CSF should be collected routinely as part of future studies to facilitate the extension of these findings to larger patient cohorts.

Outcome of patients with intracranial non-germinomatous germ cell tumors-lessons from the SIOP-CNS-GCT-96 trial

Background

Following promising results to increase survival and reduce treatment burden in intracranial non-germinomatous germ cell tumors (NGGCTs), we conducted a European study using dose-intense chemotherapy followed by risk-adapted radiotherapy.

Methods

All patients received 4 courses of cisplatin/etoposide/ifosfamide. Non-metastatic patients then received focal radiotherapy only (54 Gy); metastatic patients received 30 Gy craniospinal radiotherapy with 24 Gy boost to primary tumor and macroscopic metastatic sites.

Results

Patients with localized malignant NGGCT (n = 116) demonstrated 5-year progression-free survival (PFS) and overall survival (OS) of 0.72 ± 0.04 and 0.82 ± 0.04, respectively. Primary tumor sites were: 67 pineal, 35 suprasellar, 5 bifocal, 9 others. One patient died postsurgery in clinical remission; 3 patients progressed during treatment and 27 (23%) relapsed afterward. Fourteen were local, 6 combined, and 7 distant relapses (outside radiation field). Seventeen of the 27 relapsed patients died of disease. Patients with metastatic disease (n = 33) demonstrated 5-year PFS and OS of 0.68 ± 0.09 and 0.75 ± 0.08, respectively; 1 patient died following progression on treatment and 9 (27%) relapsed afterward (5 local, 1 combined, 3 distant). Only one metastatic patient with recurrence was salvaged. Multivariate analysis identified diagnostic alpha-fetoprotein level (serum and/or cerebrospinal fluid level >1000 ng/mL, 19/149 patients, of whom 11 relapsed; P < 0.0003) and residual disease following treatment, including after second-look surgery (n = 52/145 evaluable patients, 26 relapsed; P = 0.0002) as significant prognostic indicators in this cohort.

Conclusion

In localized malignant NGGCT, craniospinal radiotherapy could be avoided without increased relapses outside the radiotherapy field. Chemotherapy and craniospinal radiotherapy remain the gold standard for metastatic disease.

Neuroendoscopy via an Extremely Narrow Foramen of Monro: A Case Report

Herein, safe and reliable neuroendoscopic biopsy via an extremely narrow foramen of Monro (ENFM) for a non-hydrocephalic patient with hypothalamic and pineal region tumors was successfully applied. A 17-year-old boy presented with hypothalamic manifestations attributed to hypothalamic and pineal region tumors. Small ventricles were seen. Intraoperatively, to advance different diameter steerable fiberscopes via ENFM, the third ventricle was flushed to induce a moment increase in the intraventricular pressure with subsequent dilatation of FM. Postoperative course was uneventful. Histopathological studies revealed a yolk sac tumor. Adjuvant therapy was applied. Follow-up neuroimaging disclosed marvellous improvement of the condition. His symptoms gradually improved.

CNS germ cell tumors: a clinical review and future directions

CNS germ cell tumors (GCT) are rare tumors that arise in midline brain regions (mostly pineal or suprasellar). They are of two types, germinoma and nongerminomatous GCT (NGGCT) which include teratoma, choriocarcinoma, yolk sac, embyronal carcinoma and mixed GCT. Tissue is needed for diagnosis unless serum or cerebrospinal fluid markers, b-HCG or AFP, are elevated. Germinomas can be cured with radiation therapy (RT) alone (whole ventricle fields, if localized), but chemotherapy may permit RT dose-reduction. Best outcomes for NGGCT are with RT and chemotherapy. Craniospinal RT is needed for all disseminated tumors and best survival for localized NGGCT has included craniospinal RT. Recent genetic findings in CNS GCT may lead to therapies targeting their oncogenic pathways.

A pipeline to quantify serum and cerebrospinal fluid microRNAs for diagnosis and detection of relapse in paediatric malignant germ-cell tumours

Background:

The current biomarkers alpha-fetoprotein and human chorionic gonadotropin have limited sensitivity and specificity for diagnosing malignant germ-cell tumours (GCTs). MicroRNAs (miRNAs) from the miR–371–373 and miR–302/367 clusters are overexpressed in all malignant GCTs, and some of these miRNAs show elevated serum levels at diagnosis. Here, we developed a robust technical pipeline to quantify these miRNAs in the serum and cerebrospinal fluid (CSF). The pipeline was used in samples from a cohort of exclusively paediatric patients with gonadal and extragonadal malignant GCTs, compared with appropriate tumour and non-tumour control groups.

Methods:

We developed a method for miRNA quantification that enabled sample adequacy assessment and reliable data normalisation. We performed qRT–PCR profiling for miR–371–373 and miR–302/367 cluster miRNAs in a total of 45 serum and CSF samples, obtained from 25 paediatric patients.

Results:

The exogenous non-human spike-in cel–miR–39–3p and the endogenous housekeeper miR–30b–5p were optimal for obtaining robust serum and CSF qRT–PCR quantification. A four-serum miRNA panel (miR–371a–3p, miR–372–3p, miR–373–3p and miR–367–3p): (i) showed high sensitivity/specificity for diagnosing paediatric extracranial malignant GCT; (ii) allowed early detection of relapse of a testicular mixed malignant GCT; and (iii) distinguished intracranial malignant GCT from intracranial non-GCT tumours at diagnosis, using CSF and serum samples.

Conclusions:

The pipeline we have developed is robust, scalable and transferable. It potentially promises to improve clinical management of paediatric (and adult) malignant GCTs.

Unusual behaviour of a pineal germinoma mimicking neurosarcoidosis and metastasising along the endoscopic route

A previously healthy man underwent endoscopic biopsy for a suspected pineal germinoma. Histology and immunohistochemistry did not confirm the preoperative diagnosis, and neurosarcoidosis was hypothesised because of the presence of granulomatous reaction. The patient remained in good health for 3 years and was still asymptomatic when a control MRI showed metastasis implantation along the endoscopic route. A redobiopsy provided the diagnosis of germinoma, but was complicated by severe ventricular haemorrhage requiring emergency clot excision. Postoperative clinical conditions were so severe that the treatment of germinoma was postponed. Three months later, repeated MRI showed tumour progression. Chemotherapy promoted good tumour regression so that the treatment was completed by radiation therapy. The tumour completely disappeared on MRI, but the patient remained severely disabled because of the haemorrhage.

Intracranial germ cell tumors: a single-institution experience

BACKGROUND AND OBJECTIVES

Intracranial germ cell tumors (GCTs) are not a common disease. We reviewed the experience of a single institution to determine the variables that affect treatment outcome.

DESIGN AND SETTING

A retrospective review of patients with the diagnosis of intracranial germ cell tumors treated in a single institution (KFSHRC) during the period from March 1985 to December 2007.

PATIENTS AND METHODS

Fifty-seven patients with the diagnosis of intracranial GCT were recorded in the KFSHRC Tumor Registry during the period from 1985 to 2007. Seven patients with a pineal region tumor treated as germinomas in the earlier years without a tissue diagnosis were excluded. This retrospective study was restricted to the remaining 50 patients with a tissue or marker diagnosis: 31 germinomas and 19 non-germinomatous germ cell tumors (NGGCTs).

RESULTS

The 10-year overall survival (OS), event-free survival (EFS) and relapse-free survival (RFS) were 87%, 88% and 96% for patients with germinoma, with a median follow-up of 4.5 (range 2-17) years, compared with 26%, 29% and 46% for patients with NGGCT with a median follow-up of 3 (range 1.5-13) years. For NGGCT, variables favorably influencing OS were younger age (< 16 y vs ≥16 y, P=.01), higher radiation dose (>50 Gy vs ≤50 Gy; P=.03) and later year of diagnosis (>1990 vs <1990 P=.002).

CONCLUSIONS

Tissue diagnosis of GCTs is mandatory prior to treatment except for patients with elevated markers. In germinoma, localized radiotherapy (RT) for M0 patients may be adequate. Long-term follow-up is needed to define the benefit of adding chemotherapy. For NGGCT, the use of combined modality treatment and RT dose ;gt;50 Gy are important factors that influence the outcome. Second-look surgery and resection of residual/ refractory tumors is always recommended.

Nationwide investigation of the current status of therapeutic neuroendoscopy for ventricular and paraventricular tumors in Japan

OBJECT

The authors report their investigation on the current status of neuroendoscopic biopsy for ventricular and paraventricular tumors as well as treatment for associated hydrocephalus in Japan.

METHODS

Patients who had undergone therapeutic neuroendoscopy between 2005 and 2009 were included in this study. The main items examined were age; sex; localization of tumor; pathological diagnosis using biopsy; the presence, treatment, and efficacy of treatment of associated hydrocephalus; perioperative complications; activities of daily living (ADL) before and after therapeutic neuroendoscopy; and the presence of dissemination during the postoperative course.

RESULTS

Seven hundred fourteen patients from 123 sites (462 male and 252 female patients, mean age 33.3 years) were enrolled. Localization of the tumor was mainly classified into the lateral ventricle in 91 patients, the third ventricle in 339, the fourth ventricle in 18, the suprasellar region in 75, and other paraventricular areas in 191 patients. The most commonly observed tumors were germ cell tumors in the third ventricle (177 cases [39%]), cystic lesions in the suprasellar region (56 cases [75%]), and astrocytic tumors in the thalamus-basal ganglia (71 cases [38%]). Although 641 (92.8%) of 691 patients could receive neuroendoscopic diagnosis using biopsy, the diagnosis obtained with endoscopic biopsy differed from the final diagnosis based on subsequent craniotomy in 18 patients and clinical course in 3 patients. Of these 21 patients, 7 had astrocytic tumors, 4 had pineal tumors, 6 had germ cell tumors, and 4 had other tumors. The final diagnostic accuracy rate was 89.7%. Associated hydrocephalus was observed in 517 patients (72.4%), of whom 316 and 39 underwent third ventriculostomy and fenestration of the septum, respectively. The response rates were 96.2% and 89.7%, respectively. Third ventriculostomy was required for recurrence of hydrocephalus in 41 patients (13.0%), and the long-term response rate was therefore 83.2% (263 of 316 patients). Perioperative complications other than fever, such as new onset of or progressive hydrocephalus, infection due to CSF leakage, and bleeding in the ventricle or tumor, were found in 81 patients (11.3%). The median Karnofsky Performance Scale score before endoscopic surgery was 80, but it increased to 90 after surgery. The score was thus significantly increased after surgery (p < 0.0001, Mann-Whitney U-test). Activities of daily living after surgery decreased due to perioperative complications in 15 patients (2.1%). The incidence of new dissemination after endoscopic biopsy was 6.8% and not high compared with routine surgical treatment.

CONCLUSIONS

The authors concluded that neuroendoscopic diagnosis using biopsy for ventricular and paraventricular tumors is adequately accurate and safe. It was demonstrated that endoscopic procedures play important roles not only in the treatment of hydrocephalus associated with intra- and paraventricular tumors but also in significantly improving ADL. Furthermore, the long-term outcome of endoscopic third ventriculostomy was clearly favorable.

Feasibility of neuroendoscopic biopsy of pediatric brain tumors

PURPOSE

The purpose of this study was to investigate the potential value of neuroendoscopic biopsies in pediatric patients with peri- or intraventricular tumors.

METHODS

From 2001 to 2008, 49 pediatric patients (mean age, 12.16 years) with tumors located in the intraventricular or paraventricular areas underwent neuroendoscopic biopsy, with or without simultaneous endoscopic third ventriculostomy. Neuroendoscopic biopsies were performed to verify the histological diagnosis of neoplasms and to establish pathological diagnoses necessary for planning appropriate treatment strategies.

RESULTS

In 45 of 49 patients (91.8%) neuroendoscopic biopsy specimens were appropriate for diagnosis and revealed 27 germinomas, 11 astrocytomas, and one ependymoma, etc. The tumor location included the pineal gland (n = 28), thalamus (n = 7), intraventricle (n = 3), hypothalamus (n = 3), suprasellar area (n = 2), and diffuse multifocal area (n = 3). In two patients (4.1%) biopsy specimens were informative but not diagnostic. Tumor tissue specimens were undiagnostic in two patients (4.1%). There were eight transient morbidities, including four EOM limitations, two central DI, one EVD infection, and one CSF leakage. One patient experienced postoperative tumor bleeding requiring emergent operation. There was no case of operative mortality.

CONCLUSION

Neuroendoscopic biopsy can be considered as the first choice for tissue sampling of periventricular and intraventricular tumors with acceptable risks.

Surgical management of primary central nervous system germ cell tumors: proceedings from the Second International Symposium on Central Nervous System Germ Cell Tumors

The successful treatment of children with a primary CNS germ cell tumor can be greatly influenced by the neurosurgeon involved in the diagnostic and therapeutic care of these children. Variability in surgical philosophies no doubt exists due to the relatively infrequent incidence of these tumors, a lack of consensus regarding diagnostic and therapeutic approaches, and the advent of recent surgical innovations. Many of these issues were discussed at the Second International Symposium on Central Nervous System Germ Cell Tumors through presented abstracts and invited presentations. The neurosurgical aspects of these proceedings are summarized here in an effort to present the agreed-upon and debated issues that may confront the pediatric neurosurgeon.

Endoscopic options in management of posterior third ventricular tumors

OBJECTIVE

A spectrum of both radiosensitive and radio-resistant lesions occurs in the region of the posterior third ventricle (PTV). Most of these are associated with hydrocephalus requiring a cerebrospinal fluid diversion procedure. The present study aims to assess the effectiveness of endoscopic biopsy and third ventriculostomy (ETV) in these patients.

MATERIALS AND METHODS

Twenty-four patients with PTV lesions with moderate to severe hydrocephalus were managed prospectively. All patients underwent ETV and biopsy of the lesion during the same procedure. The ETV could be performed in all patients, where as in 23, a successful biopsy could be obtained. The ETV was successful in 22 patients; it failed in 2 patients requiring shunt insertion. A positive biopsy was obtained in all the patients (pinealocytoma 4, pinealoblastoma 10, embryonal cell carcinoma 1, germinoma 2, oligodendroglioma 1, astrocytoma 2, tuberculoma 4). All patients were subsequently managed with further surgery, radiation, and chemotherapy either alone or in combination depending on the pathology. One patient with a tumor bed hematoma required clot evacuation. The follow-up period ranged from 12 to 36 months. Two patients died, one during hospital stay with a tumor bed hematoma and another at 6 months follow-up due to extensive leptomeningeal spread.

CONCLUSIONS

The high yield of endoscopic biopsy (100%) and success of ETV (91%) emphasizes its role in management of the diverse group of PTV lesions in arriving at the optimal definitive management.

Neurofiberscopic biopsy of tumors of the pineal region and posterior third ventricle: indications, technique, complications, and results

OBJECTIVE

Evaluation of results of the neurofiberscopic biopsy of tumors of the pineal region and posterior third ventricle.

METHODS

From 2001 to 2004, 23 patients (mean age, 30.6 yr) with tumors located in the pineal region or posterior third ventricle underwent neurofiberscopic biopsy with simultaneous third ventriculostomy. The procedure was indicated for verification of the histological diagnosis of the neoplasm, which was planned to be treated by radiotherapy and/or chemotherapy without open surgery (eight patients), establishment of the pathological diagnosis for further choice of the most appropriate treatment strategy (11 patients), differentiation of the recurrent neoplasm and radiation necrosis (two patients), and decompression of the large tumor-associated cyst (two patients). In six previously shunted patients, substitution of the ventriculoperitoneal shunt on the third ventricle stoma was performed.

RESULTS

There was no postoperative mortality or permanent morbidity. In all cases, the obtained tissue sample was sufficient for pathological diagnosis. Transient postoperative complications included fever (15 patients), nausea and vomiting (three patients), and diplopia (one patient). On the long-term follow-up, delayed third ventricular stoma failure caused by tumor regrowth and scar formation was found in one patient, and dissemination of the malignant glioma through the subarachnoid space was found in another patient.

CONCLUSION

Neurofiberscopic biopsy represents a useful method for sampling of tumors of the pineal region and posterior third ventricle, which can be effectively used in both previously shunted and shunt-free patients.

Correlation of endoscopic biopsy with tumor marker status in primary intracranial germ cell tumors

We retrospectively analyzed the results of eight patients who underwent endoscopic biopsy of a newly diagnosed primary intracranial germ cell tumor (GCT), and correlated tumor pathology with serum and cerebrospinal fluid (CSF) tumor markers and treatment outcome in order to determine the reliability of GCT sampling by this method. A biopsy diagnosis was made in each patient, and the tumor histology correlated with tumor marker measurements for all six patients diagnosed with germinoma and for one with a yolk sac tumor. One biopsy revealed only mature teratoma, an inconclusive result since the patient's serum and CSF tumor markers were elevated. No morbidity was experienced as a result of the operative procedure. Five of six patients diagnosed with germinoma responded completely to radiation therapy and are without evidence of disease, while one suffered a likely germinoma recurrence and was subsequently successfully retreated. We conclude that endoscopic biopsy of marker-negative germ cell tumors is a safe, reliable method of establishing a diagnosis of germinoma. However, endoscopic biopsy may fail to yield an accurate diagnosis in cases of malignant non-germinomatous tumor. We would thus conclude that when primary germ cell tumor is considered, endoscopic tumor biopsy is recommended in patients with a negative biochemical analysis, but not suggested for patients presenting with elevated tumor markers.

Radiotherapy of localised intracranial germinoma: time to sever historical ties?

The optimum management of localised intracranial germinoma remains controversial. Cure rates for this rare CNS tumour, which arises mainly in adolescents, exceed 90% at 10 years, and limitation of treatment-related late morbidity is therefore essential. Craniospinal radiotherapy plus boost is perceived to be the gold-standard treatment, but there have been suggestions that reduced-volume radiotherapy could be adequate for cure. We reviewed publications since 1988 to compare patterns of disease relapse and cure rates after craniospinal radiotherapy, reduced-volume irradiation alone (i.e., whole-brain or whole-ventricular irradiation followed by a boost), and focal or localised irradiation alone. The recurrence rate after whole-brain or whole-ventricular radiotherapy plus boost was 7.6% compared with 3.8% after craniospinal radiotherapy, with no predilection for isolated spinal relapses (2.9% vs 1.2%). We challenge the consensus that craniospinal radiotherapy is the best treatment for localised germinomas and conclude that reduced-volume radiotherapy plus boost should replace craniospinal radiotherapy when a radiotherapy-only approach is used.