Multimodality therapy for CNS mixed malignant germ cell tumors (MMGCT): results of a phase II multi-institutional study

Proton therapy for pediatric diencephalic tumors

Diencephalic tumors tend to be low grade tumors located near several critical structures, including the optic nerves, optic chiasm, pituitary, hypothalamus, Circle of Willis, and hippocampi. In children, damage to these structures can impact physical and cognitive development over time. Thus, the goal of radiotherapy is to maximize long term survival while minimizing late effects, including endocrine disruption leading to precocious puberty, height loss, hypogonadotropic hypogonadism, and primary amenorrhea; visual disruption including blindness; and vascular damage resulting in cerebral vasculopathy. Compared to photon therapy, proton therapy offers the potential to decrease unnecessary dose to these critical structures while maintaining adequate dose to the tumor. In this article, we review the acute and chronic toxicities associated with radiation for pediatric diencephalic tumors, focusing on the use of proton therapy to minimize treatment-related morbidity. Emerging strategies to further reduce radiation dose to critical structures will also be considered.

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.

Relapsing intracranial germ cell tumours warrant retreatment

BACKGROUND

The optimal therapeutic strategy for relapsing intracranial germ cell tumours (IGCTs) has not been clearly established.

METHODS

Relapses of IGCTs, occurring from 01/01/1990 to 31/12/2014, were retrieved from the Societe Française d'Oncologie Pediatrique-TGM 90, 92 and GCT 96 protocols, and from the National Childhood Solid Tumour Registry. Refractory IGCTs were excluded.

RESULTS

Forty-four relapsing IGCTs were identified: 14 were initially treated for histologically proven germinomas (germinoma group), 5 for non-histologically proven germinomas (putative germinoma group) and 25 for non-germinomatous germ cell tumours (NGGCTs) (NGGCT group). In the germinoma group, the 5-year event-free survival (EFS) and overall survival (OS) were 79% (95% confidence interval [CI]: 47-93) and 86% (95% CI: 54-96), respectively. Only one of the 11 patients treated with reirradiation experienced a further relapse. A trend of better EFS was observed for relapses at sites that were not initially involved: 5-year EFS of 100% versus 67% (95% CI: 28-88), p = 0.09. In the putative germinoma group, 4 of 5 patients experienced a further event, leading to 2 deaths. In the NGGCT group, the 5-year EFS and OS were 56% (95% CI: 35-73) and 60% (95% CI: 38-76), respectively. A significant improvement in outcomes after high-dose chemotherapy (HDC) was observed: 5-year OS of 72% (95% CI: 46-87) versus 29% (95% CI: 4-61), p = 0.006.

CONCLUSION

Relapsing germinomas are highly curable; reirradiation appears to play a key role. Histological proof at initial diagnosis if markers are negative is crucial. Despite inferior outcomes relapsing, NGGCTs can be cured in a significant proportion of cases provided intensive treatment including HDC is applied.

Intensity-modulated ventricular irradiation for intracranial germ-cell tumors: Survival analysis and impact of salvage re-irradiation

Background and purpose

The roles of surgery, chemotherapy, and parameters of radiation therapy for treating very rare central nervous system germ cell tumors (CNS-GCT) are still under discussion. We aimed to evaluate the survival and recurrence patterns of patients with CNS-GCT treated with chemotherapy followed by whole ventricle irradiation with intensity-modulated radiation therapy.

Materials and methods

We reviewed the clinical outcomes of 20 consecutive patients with CNS-GCT treated with chemotherapy and intensity-modulated radiation therapy from 2004 to 2014 in two partner institutions.

Results

Twenty children with a median age of 12 years were included (16 males). Sixteen tumors were pure germinomas, and 4 were non-germinomatous germ cell tumors (NGGCT). All patients were treated with intensity-modulated radiation therapy guided by daily images, and 70% with volumetric intensity-modulated arc radiotherapy additionally. The median dose for the whole-ventricle was 25.2 Gy (range: 18–30.6 Gy) and 36 Gy (range: 30–54 Gy) for the tumor bed boost. The median post-radiation therapy follow-up was 57.5 months. There were 3 recurrences (2 NGGCT and 1 germinoma that recurred as a NGGCT), with 1 death from the disease and the other 2 cases each successfully rescued with chemotherapy and craniospinal irradiation. The overall survival at 5 years was 95% and disease-free survival was 85%.

Conclusions

The results of this study suggest that the combined use of chemotherapy followed by whole ventricle irradiation with intensity-modulated radiation therapy is effective for CNS-GCTs, especially pure germinomas. Even being rescued with craniospinal irradiation, the NGGCT cases have markedly worse prognoses and should be more rigorously selected for localized treatment.

Critical review of the management of primary central nervous nongerminomatous germ cell tumors

Multimodal strategies have significantly improved the outcomes for patients with central nervous system nongerminomatous germ cell tumors. Two large cooperative group studies have recently reported much improved outcomes compared with historical series. However, a substantial proportion of patients still attain inadequate responses to initial chemotherapy prior to irradiation, with adverse impact upon survival; optimal induction chemotherapy regimens and radiotherapy strategies are as yet unidentified. Outcomes for patients with relapsed disease remain poor. There is an obvious need to incorporate molecular studies within prospective clinical trials that will likely lead to the incorporation of targeted, more effective future treatment strategies.

Reduced-volume radiotherapy for patients with localized intracranial nongerminoma germ cell tumors

Craniospinal irradiation is standard radiotherapy (RT) for localized intracranial nongerminoma germ cell tumors (NGGCT). Given its toxicity, there is interest in using smaller fields. We examined outcomes of NGGCT patients receiving reduced-volume RT at a single institution. Records of 16 patients who received reduced-volume RT as part of definitive treatment between 1996 and 2016 were reviewed. Median age at presentation was 10.8 years (range 4.6-41.0 years). Ten patients had pineal tumors and 6 had suprasellar tumors. All received chemotherapy and 9 patients received second-look surgery thereafter. RT volume was tumor-only to a median of 54 Gy (range 50.4-54 Gy) in 3 patients and whole-ventricle irradiation to a median of 30.6 Gy (range 30.6-36 Gy) with a boost to 54 Gy in 13 patients. Median follow-up was 4.1 years (range 1.9-19.3 years). Three patients recurred locally at a median 9.9 months (range 9.6-10.6 months) after diagnosis, and one of these developed leptomeningeal relapse after 30 months. One patient expired from disease 2.6 years post-diagnosis and another due to stroke 19.3 years post-diagnosis. Fourteen patients are alive with no evidence of disease. Kaplan-Meier estimates of the 4-year overall survival and failure-free survival are 92% (95% confidence interval [CI], 57-99%) and 81% (95% CI 53-94%), respectively. Excellent disease control was observed in these patients with no initial relapses outside of these RT fields. The results of ACNS1123 may better delineate patterns of failure and identify subgroups likely to benefit from this approach.

Neurocognitive and Psychological Functioning of Children with an Intracranial Germ Cell Tumor

Purpose

This study was conducted to investigate the neurocognitive functioning of children with intracranial germ cell tumor (IGCT) prior to receiving proton beam therapy (PBT), and to identify differential characteristics of their neurocognitive functioning depending on tumor location. As a secondary object of this study, neurocognitive functions were followed up at 1-2 years after PBT to examine early post-treatment changes.

Materials and Methods

Between 2008 and 2014, 34 childrenwith IGCT treatedwho received PBT atNational Cancer Center, Korea were enrolled in this study. Standardized neurocognitive tests of intelligence, memory, and executive functioning were performed with baseline psychological assessments using the Child Behavior Checklist (CBCL). Follow-up assessments after PBT were conducted in 20 patients (T2). The results were analyzed based on the locations of tumors, which included the suprasellar, pineal gland, basal ganglia, and bifocal regions.

Results

The neurocognitive function of IGCT patients was significantly lower than that of the normal population in performance intelligence quotient (p=0.041), processing speed (p=0.007), memory (p < 0.001), and executive functioning (p=0.010). Patients with basal ganglia tumors had significantly lower scores for most domains of neurocognitive functioning and higher scores for CBCL than both the normal population and patients with IGCT in other locations. There was no significant change in neurocognitive function between T1 and T2 for all types of IGCT patients in first 1-2 years after PBT.

Conclusion

Tumor location significantly affects the neuropsychological functioning in patients with IGCT. Neuropsychological functioning should be closely monitored from the time of diagnosis in IGCT patients.

Intracranial germ cell tumors: a multi-institutional experience from three tertiary care centers in India

OBJECTIVE

Central nervous system germ cell tumors (CNS GCTs) are relatively rare neoplasms. Incidence of CNS GCTs in Western literature is low (0.3-0.6 %) as compared to East Asia (3-4 %). No large study is available on CNS GCTs from India.

METHODS

Intracranial GCT cases were retrieved from databases of three tertiary care institutes in India; clinicopathological data was reviewed.

RESULTS

Ninety-five intracranial GCT cases were identified, accounting for 0.43 % of CNS tumors. Median age was 12 years (range, birth to 48 years); male preponderance was noted (66 %). Most patients (86.3 %) were aged <18 years. Pineal location was most common (45 %) and was associated with male gender and age >14 years. Germinoma was the commonest histopathological type (63.2 %), followed by teratoma (20 %). Suprasellar location was associated with germinoma histology. Follow-up was available for 71 patients (median, 15 months). Of these, 48 received adjuvant chemotherapy and/or radiotherapy. At the last follow-up, 44 patients showed no evidence of disease. Age >10 years, male gender, pineal location, and germinoma histology were associated with favorable outcome.

CONCLUSION

This is the first multicentric study from India establishing that incidence of CNS GCT in India is similar to that in the West and differs from that in East Asian countries. However, similar to both, germinoma is the commonest histological type, and pineal location is most frequent. Studies on molecular alterations based on ethnicity and geographical location are necessary to provide clarity on differences in incidence. Attention needs to be focused on decreasing treatment heterogeneity and minimizing treatment-related morbidity and mortality, improving the cure rate of these highly treatable tumors.

Utility of MRI versus tumor markers for post-treatment surveillance of marker-positive CNS germ cell tumors

Patients with marker-positive central nervous system (CNS) germ cell tumors are typically monitored for tumor recurrence with both tumor markers (AFP and b-hCG) and MRI. We hypothesize that the recurrence of these tumors will always be accompanied by an elevation in tumor markers, and that surveillance MRI may not be necessary. We retrospectively identified 28 patients with CNS germ cell tumors treated at our institution that presented with an elevated serum or cerebrospinal fluid (CSF) tumor marker at the time of diagnosis. We then identified those who had a tumor recurrence after having been in remission and whether each recurrence was detected via MRI changes, elevated tumor markers, or both. Four patients suffered a tumor recurrence. Only one patient had simultaneously elevated tumor markers and MRI evidence of recurrence. Two patients had evidence of recurrence on MRI without corresponding elevations in serum or CSF tumor markers. One patient had abnormal tumor markers with no evidence of recurrence on MRI until 6 months later. We conclude that in patients with marker-positive CNS germ cell tumors who achieve complete remission, continued surveillance imaging in addition to measurement of tumor markers is indicated to detect recurrences.

Ophthalmological outcomes of patients treated for pineal region tumors

OBJECTIVE The ophthalmological outcomes of children treated for pineal tumors have received limited attention in the literature. METHODS This paper reviews the outcomes of 29 children treated for pineal and posterior third ventricular tumors in the contemporary era using chemotherapy, radiotherapy, and resection as defined by the histology and/or marker profile of the tumor. RESULTS At the time of diagnosis, all patients except 1 had hydrocephalus and all had ophthalmological involvement. Papilledema was found in 69% of patients. Seventy-five percent of patients had partial or complete Parinaud's syndrome, and diplopia or blurred vision was noted in the remaining patients. Visual acuity was impaired in 8 patients. Outcomes were dependent on the histology of the tumor and the treatment required. Those patients who did not requiring resection showed a lower rate of ophthalmological worsening during treatment and greater long-term improvement, in particular with respect to up-gaze palsy. Patients who underwent resection for postchemotherapy residual disease or primary resection showed greater worsening during treatment and lesser degrees of recovery. All patients with impaired visual acuity improved with treatment. CONCLUSIONS As the mortality of germ cell and other pineal tumors decreases, posttreatment morbidity remains, specifically that related to convergence nystagmus, accommodation, and diplopia. In addition to survival, ophthalmological morbidity should be reported in studies concerning the outcomes of treatment for pineal neoplasms.

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.

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.