Long-term results of radiotherapy for intracranial germinoma: a multi-institutional retrospective review of 126 patients

Long-Term Outcome and Social-Intellectual Ability of Patients With Basal Ganglia Germinoma

BACKGROUND

In this study, we aimed at delineating the still ambiguous clinical characteristics and long-term outcomes of basal ganglia (BG) germinoma from the aspect of recurrence-free survival as well as social and intellectual activity.

METHODS

We retrospectively reviewed medical records and imaging data for 12 patients with BG germinoma diagnosed and treated between 1996 and 2020, collecting the most recent status via medical records or telephone from the patients.

RESULTS

The tumors involved the right and left sides and bilateral locations in three, seven, and two cases, respectively. The median follow-up period was 179 months. Six patients exhibited onset neuropsychologic symptoms, for example, cognitive decline or behavior disorder. We evaluated the intelligence quotient (IQ) in 10 patients and observed significantly lower IQ scores in six patients with neuropsychologic symptoms. Patients with right-sided lesions displayed average IQ levels (median 106), whereas those with left-sided or bilateral lesions had reduced IQ (median 67). A complete response was achieved by primary chemoradiotherapy in all patients. Three patients who underwent focal or whole-ventricle irradiation experienced recurrence, whereas no recurrence was observed in patients who received whole-brain irradiation (WBI). Concerning the neurocognitive outcomes, three and six patients with unilateral right and left lesions were living self-independently (Karnofsky Performance Status [KPS] ≧ 70), whereas the three remaining patients (one with left and two with bilateral lesions) had a dependent status (KPS <70).

CONCLUSIONS

WBI is crucial for disease control in BG germinoma. Furthermore, lesion laterality might affect neuropsychologic symptoms including IQ at diagnosis and neurocognitive outcomes in BG germinoma.

Treatment Outcomes and Prognostic Factors of Intracranial Germ Cell Tumors: A Single Institution Retrospective Study

BACKGROUND

This study analyzed the epidemiology and treatment outcomes of germ cell tumor patients at a single institution.

METHODS

A retrospective analysis was conducted on intracranial germ cell tumor (iGCT) patients treated at a single tertiary hospital from 2004 to 2019. Patients were categorized based on treatment modality: Korean Society for Pediatric Neuro-Oncology (KSPNO) protocol or bleomycin, etoposide, and cisplatin with radiation therapy.

RESULTS

Forty-nine iGCT patients treated with combined chemotherapy and radiotherapy were analyzed. The median age was 19 years (range: 6-40), with a median follow-up duration of 148.0 months (range: 10.5-265.5). Tumors were most common in the pineal gland (51.0%). Although no significant differences in outcomes were observed between treatment modalities, outcomes varied significantly by pathological type. The 10-year progression-free survival rates for germinoma and non-germinomatous germ cell tumors (NGGCTs) were 88.1% and 32.7%, respectively (p=0.003), while the 10-year overall survival rates were 92.9% and 67.5%, respectively (p<0.001). Fourteen patients experienced CTCAE (Common Terminology Criteria for Adverse Events) grade ≥3 adverse events, with one event-related death.

CONCLUSION

Pure germinoma demonstrated higher survival and lower recurrence rates compared to NGGCT. The KSPNO protocol appears to be an acceptable and safe treatment option for iGCT patients. Further multi-institutional studies with larger cohorts are warranted.

Optimal treatment approach for intracranial germinoma: a systematic review and meta-analysis

BACKGROUND

To determine the optimal treatment modality for intracranial germinoma (IG).

MATERIALS AND METHODS

A search of Medline, Embase, Web of Science and Cochrane Library was conducted up to April, 2024. Pooled risk ratio (RR) and 95% confidence interval (CI) were calculated. Subgroup analysis was applied according to radiotherapy (RT) alone or with chemotherapy (CTx).

RESULTS

Total 37 studies were included in systematic review. Most IG patients were treated with biopsy or resection followed by RT with or without CTx. Prognosis of IG patients with different surgical resection is similar. Meta-analyses demonstrated focal field RT were with higher recurrence rate compared with craniospinal irradiation (CSI) [RR = 7.128, 95% CI (5.083, 9.995)], whole-brain RT (WBRT) [RR = 4.094, 95% CI (2.923, 5.735)] or whole-ventricle RT (WVRT) [RR = 3.361, 95% CI (2.126, 5.312)]; both WBRT and WVRT were also with higher recurrence compared with CSI; but no significant difference in recurrence and mortality between WVRT and WBRT. Total 24 studies reported treatment-related acute and/or late toxicity, combination CTx increased acute toxic, and expanded RT field and/or dose increased late toxicity.

CONCLUSION

Based on our findings, focal field RT is not recommended regardless of whether combined with CTx for intracranial pure germinoma. Although CSI is associated with better local control than other reduced-field RT, considering the potential toxicity and pattern of relapse, whole ventricles irradiation is more reasonable for localized or nonmetastatic germinoma. Reduced-dose CSI with or without chemotherapy is effective in metastatic or disseminated IG.

Intracranial germ cell tumors: a view of the endocrinologist

Intracranial germ cell tumors (iGCTs) are rare malignant neoplasms that mainly affect children and adolescents. The incidence, clinical presentation, and prognosis of iGCTs exhibit high heterogeneity. Previous studies have primarily focused on eliminating tumors, reducing tumor recurrence, and improving survival rates, while neglecting the impact of the tumors and their treatment on neuroendocrine function. Throughout the entire course of the disease, neuroendocrine dysfunction may occur and is frequently overlooked by oncologists, neurosurgeons, and radiologists. Endocrinologists, however, are more interested in this issue and have varying priorities at different stages of the disease. From onset to the diagnostic phase, most patients with iGCTs may present with symptoms related to impaired neuroendocrine function, or even experience these symptoms as their first indication of the condition. Particularly, a minority of patients with sellar/suprasellar lesions may exhibit typical imaging features and elevated tumor markers long after the onset of initial symptoms. This can further complicate the diagnosis process. During the peritumor treatment phase, the neuroendocrine function shows dynamic changes and needs to be evaluated dynamically. Once diabetes insipidus and dysfunction of the hypothalamic-pituitary-adrenal and hypothalamic-pituitary-thyroid axes occur, hormone replacement therapy should be administered promptly to ensure successful tumor treatment for the patient. Subsequently, during the long-term management phase after the completion of tumor treatment, the evaluation of growth and development as well as corresponding hormone replacement therapy are the most concerning and complex issues. Thus, this paper reviews the interest of endocrinologists in iGCTs at different stages.

Intracranial Germ Cell Tumors

Intracranial germ cell tumors are rare tumors occurring in adolescents and young adults, which include germinomas and non-germinomatous type germ cell tumors (NGGCT). In the past few decades, cooperative trial groups in Europe and North America have developed successful strategies to improve survival outcomes and decrease treatment-related toxicities. New approaches to establishing diagnosis have deferred the need for radical surgery. The 5-year event-free survival (EFS) is above 90% and even patients who present with metastatic germinoma can still be cured with chemotherapy and craniospinal irradiation. The combination of surgery, chemotherapy, and radiation therapy is tailored to patients based on grouping and staging. For NGGCT, neoadjuvant chemotherapy followed by delayed surgery for residual disease and radiotherapy can yield a 5-year EFS of 70%. Further strategies should focus on reducing long-term complications while preserving high cure rates.

Unraveling the impact of upfront chemotherapy and proton beam therapy on treatment outcome and follow-up in central nervous system germ cell tumors: a single center experience

Background

Germ cell tumors (GCT) account for a minority of central nervous system (CNS) malignancies, highly prevalent in adolescents and young adults. Despite their aggressive biological behavior, prognosis is excellent in most cases with risk stratified treatment, consisting in a combination of chemotherapy and radiotherapy. Whole ventricular irradiation (WVI) and craniospinal irradiation, the treatment of choice for localized and metastatic disease, pose significant risk of collateral effects, therefore proton beam radiation (PBT) has been recently proposed for its steep dose fallout.

Materials and methods

We report our experience in a consecutive series of 17 patients treated for CNS GCT at our Institution from 2015 to 2021.

Results

Most frequent lesion location were sellar/suprasellar (35%) and bifocal germinoma (35%), followed by pineal (18%) and thalamic (12%). Two patients (12%), had evidence of disseminated disease at the time of diagnosis. At the latest follow-up all but one patient showed complete response to treatment. The only relapse was successfully rescued by additional chemotherapy and PBT. PBT was well tolerated in all cases. No visual, neurological or endocrinological worsening was documented during and after treatment. Neuropsychological evaluation demonstrated preservation of cognitive performance after PBT treatment.

Conclusions

Our data, albeit preliminary, strongly support the favourable therapeutic profile of PBT for the treatment of CNS germ cell tumors.

Pineal germinoma in a young adult: A case report

BACKGROUND

Intracranial germinomas (GN) are rare cancers that primarily affect children, making them rarer still in adults. Standard treatment for this neoplasm includes neoadjuvant chemotherapy (NC) followed by radiotherapy (RT) or RT at a higher dose and larger field. These recommendations are based on studies focused mostly on children; it is currently unclear whether this treatment is applicable to adults.

CASE

We present a case of a 23-year-old adult male with no underlying pathologies, drug allergies, or family history of cancer, who presented for medical evaluation with blurred vision, diplopia, forgetfulness, and weight loss starting 3-4 months before the evaluation. Clinical examination indicated Parinaud's Syndrome. Magnetic resonance imaging (MRI) and computed tomography (CT) revealed a pineal tumor with ependymal dissemination in both lateral ventricles, which was causing obstructive hydrocephalus. The patient had surgery consisting of ventriculostomy, Holter shunt insertion, cisternal ventricular intubation, and cisterna magna anastomosis to improve ventricular drainage. Pathology confirmed pineal germinoma. Cerebrospinal fluid cytology and MRI of the axis were negative. Four cycles of NC were given to the patient (carboplatin, etoposide, and ifosfamide), with reduced dosage. Once a partial volumetric response was confirmed, whole-ventricular radiotherapy (WVR) was initiated with a total tumor bed dose of 45 Gy over 25 sessions in 5 weeks. Optimum clinical results were observed, and no short-term (<90 day) radiation toxicity was observed. The patient was able to resume his normal activities soon after treatment. Follow-ups over 2 years post-surgery indicated continued control of the lesion and absence of symptoms except for mild diplopia.

CONCLUSION

Although this is a case report, these data suggest that a reduced NC course and WVR may effectively treat adult GN. This protocol likely decreases the risk of undesirable NC and RT secondary effects, while providing excellent local control; however, using a narrower RT field is not recommended.

The Japan Society for Neuro-Oncology Guideline on the Diagnosis and Treatment of Central Nervous System Germ Cell Tumors

Primary CNS germ cell tumors (GCTs) are rare neoplasms predominantly observed in the pediatric and young adult populations. In line with the hypothesis that the primordial germ cell is the cell-of-origin, histopathological examinations for this pathology involve a diverse range of components mirroring the embryogenic developmental dimensions. Chemotherapy and radiotherapy are the mainstays of treatment, with surgery having a limited role for diagnosis and debulking of residual tissue after treatment. While better management has been achieved over recent decades by modifying radiation coverage and selecting appropriate chemotherapy, standardization of treatment remains challenging, partly due to the low volume of cases encountered in each institution. As the incidence is higher in East Asia, including Japan, the Japan Society for Neuro-Oncology established a multidisciplinary task force to create an evidence-based guideline for CNS GCTs. This guideline provides recommendations for multiple dimensions of clinical management for CNS GCTs, with particular focus on diagnostic measures including serum markers, treatment algorithms including surgery, radiotherapy and chemotherapy, and under-investigated but important areas such as treatment for recurrent cases, long-term follow-up protocols and long-term sequelae. This guideline serves the purpose of helping healthcare professionals keep up to date with current knowledge and standards of management for patients with this rare disease in daily clinical practice, as well as driving future translational and clinical research by recognizing unmet needs concerning this tumor.

Multi-institutional analysis of treatment modalities in basal ganglia and thalamic germinoma

BACKGROUND

Central nervous system (CNS) germinomas are treatment-sensitive tumors with excellent survival outcomes. Current treatment strategies combine chemotherapy with radiotherapy (RT) in order to reduce the field and dose of RT. Germinomas originating in the basal ganglia/thalamus (BGTGs) have proven challenging to treat given their rarity and poorly defined imaging characteristics. Craniospinal (CSI), whole brain (WBI), whole ventricle (WVI), and focal RT have all been utilized; however, the best treatment strategy remains unclear.

METHODS

Retrospective multi-institutional analysis has been conducted across 18 institutions in four countries.

RESULTS

For 43 cases of nonmetastatic BGTGs, the 5- and 10-year event-free survivals (EFS) were 85.8% and 81.0%, respectively, while the 5- and 10-year overall survivals (OS) were 100% and 95.5%, respectively (one patient fatality from unrelated cause). Median RT doses were as follows: CSI: 2250 cGy/cGy(RBE) (1980-2400); WBI: 2340 cGy/cGy(RBE) (1800-3000); WVI: 2340 cGy/cGy(RBE) (1800-2550); focal: 3600 cGy (3060-5400). Thirty-eight patients (90.5%) received chemotherapy. There was no statistically significant difference in the EFS based on initial field extent (p = .84). Nevertheless, no relapses were reported in patients who received CSI or WBI. Chemotherapy alone had significantly inferior EFS compared to combined therapy (p = .0092), but patients were salvageable with RT.

CONCLUSION

Patients with BGTGs have excellent outcomes and RT proved to be an integral component of the treatment plan. This group of patients should be included in future prospective clinical trials and the best RT field should be investigated further.

Pineal Gland Tumors: A Review

Simple Summary

Pineal neoplasms are tumors with different and variable morphological, histological, and radiological characteristics and, consequently different diagnosis and management. Due to their rarity, pineal tumors may be misdiagnosed. Pineal tumors, are divided into germ cell tumors, pineal parenchymal tumors and tumors that derive from adjacent structures. In this review, we report the clinical relevance of the main pineal gland tumors, underlining the importance of studying the triggering causes of pineal region carcinogenesis, to realize appropriate diagnosis and, consequently, better clinical management.

Abstract

The pineal gland is a small, pinecone-shaped endocrine gland that participates in the biological rhythm regulation of vertebrates. The recognized major product of the pineal gland is melatonin—a multifunctional endogenous indoleamine. Accumulating evidence suggests that the pineal gland is important for preserving ideal health conditions in vertebrate. Tumors of the pineal region account for approximately 3–11% of pediatric brain neoplasms but fewer than 1% of brain neoplasms in adults. It is fundamental to expand advanced imaging techniques together with both clinical and laboratory knowledge, to help to differentiate among pineal neoplasms and thus facilitate accurate primary diagnoses and proper therapeutic interventions. In this review, we report the gross anatomy of the pineal gland and its functional significance and discuss the clinical relevance of pineal gland tumors, underlining the importance of identifying the leading causes of pineal region masses.

Pituitary Dysfunction in Patients with Intracranial Germ Cell Tumors Treated with Radiotherapy

OBJECTIVE

To evaluate the endocrine abnormalities in intracranial germ cell tumors (iGCTs) treated with radio-therapy (RT), and to discuss the effects of RT on pituitary functions.

METHODS

Seventy-seven patients diagnosed with iGCTs who had received RT and endocrine follow-up in Huashan Hospital between January 2010 and July 2017 were retrospectively analyzed, consisting of 49 germinomas and 28 NGGCTs. The median follow-up period was 50.0 months. Fifty-one patients had radiologically proved suprasellar/sellar lesions.

RESULTS

The male to female ratio was 62/15. The median endocrine follow-up period was 19 (4, 42) months. The median age at the last endocrine visit was 18 (16, 20) years old. The 5-year overall and recurrence-free survival were both 98.7%. The overall prevalence of central adrenal insufficiency (CAI), central hypothyroidism (CHT), central hypogonadism (CHG), hyperprolactinemia, and central diabetes insipidus (CDI) was 57.3%, 56%, 56.6%, 35.3%, and 52.1%, respectively, after RT. Patients having suprasellar/sellar lesions showed significantly higher post-therapeutic prevalence of hypopituitarism than those who didn't. Compared to that before RT, CAI, CHT, and CHG weren't significantly improved while the levels of prolactin and the prevalence of CDI declined significantly (P =.03 and.001). The radiation doses to pituitary and hypothalamus between those with and without CAI, CHT, and CHG weren't significantly different.

CONCLUSION

The prevalence of hypopituitarism was high in iGCTs, especially in those with suprasellar/sellar involvement. The levels of prolactin and the prevalence of CDI declined significantly after RT. The hypopituitarism in iGCTs was mainly induced by tumor effects, and RT showed no additional damage to pituitary functions in our study.

ABBREVIATIONS

AFP = alpha-fetoprotein; CAI = central adrenal insufficiency; CDI = central diabetes insipidus; CHG = central hypogonadism; CHT = central hypothyroidism; CT = computed tomography; DA = dopamine; GH = growth hormone; βHCG = beta-human chorionic gonadotropin; HPA = hypothalamus-pituitary-adrenal; HPG = hypothalamus-pituitary-gonadal; HPL = hyperprolactinemia; HPT = hypothalamus-pituitary-thyroid; iGCT = intracranial germ cell tumor; IGF-1 = insulin-like growth factor 1; NGGCT = nongerminomatous germ cell tumors; OS = overall survival; PFS = progression-free survival; PRL = hypothalamus-pituitary-prolactin; RT = radiotherapy.

Intracranial Germinoma Misdiagnosed as Hyperthyroidism: A Case Report and Review of the Literature

Intracranial germ cell tumors (GCTs) are relatively rare, which account for 0.5% of all primary intracranial neoplasms. Intracranial germinomas most commonly occur in the pineal and suprasellar region, making up the majority of all intracranial GCTs. For its diversified clinical manifestations, the diagnosis is easily confused with other diseases. Here, we present a case of a 19-year-old boy with intracranial germinoma who was preliminarily misdiagnosed as hyperthyroidism for the symptoms of weight loss and thyroid dysfunction.

Long term toxicity of intracranial germ cell tumor treatment in adolescents and young adults

PURPOSE

The purpose of this study is to describe the long-term toxicities of intracranial germ cell tumor (IGCT) in the adolescent and young adult (AYA) population.

METHODS

We report late toxicities of a multi-center cohort of AYA patients treated for IGCT between 1975 and 2015. Charts were retrospectively reviewed for hormone deficiency, ototoxicity, seizure disorder, visual deterioration, cerebrovascular events, second neoplasm, psychiatric illness, and neurocognitive impairment. Statistical analysis was performed for late toxicities to evaluate the influence of select factors.

RESULTS

Our patient cohort included 112 patients with IGCTs; 84% of patients had a germinoma as opposed to a non-germinomatous germ cell tumor (NGGCT), median age at radiotherapy (RT) was 19 years, and median follow-up was 8.3 years. Of the 94 patients with germinoma, 32 (34%) received both chemotherapy and RT as part of their upfront treatment, while 62 (66%) received RT alone. All 18 patients with NGGCT received chemotherapy and RT. The most common late toxicity following IGCT treatments was physician-reported neurocognitive impairment, with a 10-year cumulative incidence (CI) of 38.5%. Ten-year CI of treatment-induced ototoxicity was 39.2% for patients who received cisplatin, compared to 3.6% for those who received carboplatin but no cisplatin (p < 0.005). Suprasellar/hypothalamic tumor location was associated with 10-year CI of treatment-induced hormone deficiency (36.1 vs 6.2%, p < 0.005).

CONCLUSIONS

A significant proportion of AYAs treated for IGCTs experience late effects from treatment, including neurocognitive impairment, ototoxicity, and hormone deficiency. Suprasellar/hypothalamic tumor location and cisplatin were associated with a higher risk of treatment-induced hormone deficiency and ototoxicity, respectively.

Diagnostic Capability of Cerebrospinal Fluid-Placental Alkaline Phosphatase Value in Intracranial Germ Cell Tumor

OBJECTIVE

Most types of intracranial germ cell tumors (IGCTs) are sensitive to chemoradiation. However, biopsy specimens are usually small and thus cannot be used for obtaining an accurate pathological diagnosis. Recently, the cerebrospinal fluid (CSF) placental alkaline phosphatase (PLAP) value has been considered a new biomarker of IGCTs. The present study aimed to evaluate the discriminatory characteristics of the CSF-PLAP value upon diagnosis and at the time of recurrence in patients with IGCTs.

METHODS

Between 2015 and 2019, this study included 37 patients with tumors located in the intraventricular and/or periventricular region. The CSF-PLAP level was assessed before the patients received any treatment. The PLAP level was evaluated during and after first-line chemoradiotherapy in 7 patients with IGCTs. The CSF-PLAP values were compared according to histological diagnosis, and the correlation between these values and radiographical features was assessed. The CSF-PLAP values of 6 patients with IGCTs with suspected recurrence were evaluated based on neuroimaging findings.

RESULTS

The CSF-PLAP values were significantly higher in patients with IGCTs than in those with other types of brain tumor (n = 19 vs. 18; median: 359.0 vs. <8.0 pg/mL). The specificity and sensitivity were 88 and 95%, respectively, with a cutoff value of 8.0 pg/mL. In patients with IGCT, the CSF-PLAP value was higher in patients with germinoma than in those with nongerminomatous germ cell tumors (n = 12 vs. 7; median: 415.0 vs. 359.0 pg/mL). Regarding the time course, the CSF-PLAP value decreased to below the detection limit after the reception of first-line chemoradiotherapy in all 7 patients. A significant correlation was observed between the initial CSF-PLAP value and the tumor reduction volume after receiving first-line chemoradiotherapy (p < 0.0003, R2 = 0.6165, logY = 1.202logX - 1.727). Among the patients with suspected IGCT recurrence (n = 6), the CSF-PLAP value was high in patients with recurrence (n = 3; median: 259.0 pg/mL), and that in patients (n = 3) without recurrence was below the lower detection limit.

CONCLUSIONS

The CSF-PLAP level is a useful biomarker during the initial diagnosis of IGCTs and at the time of recurrence. It may be associated with the volume of germinomatous components of tumors.

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.

OAR sparing 3D radiotherapy planning supported by fMRI brain mapping investigations

The human brain as an organ has numerous functions; some of them can be visualized by functional imaging techniques (e.g., functional MRI [fMRI] or positron emission tomography). The localization of the appropriate activity clusters requires sophisticated instrumentation and complex measuring protocol. As the inclusion of the activation pattern in modern self-tailored 3D based radiotherapy has notable advantages, this method is applied frequently. Unfortunately, no standardized method has been published yet for the integration of the fMRI data into the planning process and the detailed description of the individual applications is usually missing. Thirteen patients with brain tumors, receiving fMRI based RT planning were enrolled in this study. The delivered dose maps were exported from the treatment planning system and processed for further statistical analysis. Two parameters were introduced to measure the geometrical distance Hausdorff Distance (HD), and volumetric overlap Dice Similarity Coefficient (DSC) of fMRI corrected and not corrected dose matrices as calculated by 3D planning to characterize similarity and/or dissimilarity of these dose matrices. Statistical analysis of bootstrapped HD and DSC data was performed to determine confidence intervals of these parameters. The calculated confidence intervals for HD and DSC were (5.04, 7.09), (0.79, 0.86), respectively for the 40 Gy and (5.2, 7.85), (0.74, 0.83), respectively for the 60 Gy dose volumes. These data indicate that in the case of HD < 5.04 and/or DSC > 0.86, the 40 Gy dose volumes obtained with and without fMRI activation pattern do not show a significant difference (5% significance level). The same conditions for the 60 Gy dose volumes were HD < 5.2 and/or DSC > 0.83. At the same time, with HD > 7.09 and/or DSC < 0.79 for 40 Gy and HD > 7.85 and/or DSC < 0.74 for 60 Gy the impact of fMRI utilization in RT planning is excessive. The fMRI activation clusters can be used in daily RT planning routine to spare activation clusters as critical areas in the brain and avoid their high dose irradiation. Parameters HD (as distance) and DSC (as overlap) can be used to characterize the difference and similarity between the radiotherapy planning target volumes and indicate whether the fMRI delivered activation patterns and consequent fMRI corrected planning volumes are reliable or not.

The relationship between ventricular volume and whole-brain irradiation dose in central nervous system germ cell tumors

BACKGROUND

Advanced irradiation techniques, including intensity-modulated radiation therapy (IMRT), aim to limit irradiation to adjoining tissues by conforming beams to a well-defined volume. In intracranial germinomas, whole-ventricular IMRT decreases the volume of irradiation to surrounding parenchyma. This study examined the relationship between ventricular volume and radiation dose to surrounding tissue.

PROCEDURE

We retrospectively reviewed age, sex, ventricular and brain volume, ventricular dose, and volume of brain that received 12 Gy (V12) for patients diagnosed with germ cell tumors at our institution treated with whole-ventricular IMRT between 2002 and 2016. Variables were assessed for correlation and statistical significance.

RESULTS

Forty-seven patients were analyzed. The median whole-ventricular irradiation dose was 24 Gy with a median boost dose of 30 Gy. The median ventricular volume was 234.3 cm³ , and median brain volume was 1408 cm³ . There was no significant difference between mean ventricular volume of suprasellar versus pineal tumors (P = .95). The median V12 of the brain, including the ventricles, was 58.9%. The strongest correlation was between ventricular volume and V12, with an r² (coefficient of determination) of .47 (P < .001). Multiple regression analysis indicated that total boost dose and boost planning target volume significantly predicted V12 (P < .001).

CONCLUSIONS

Although whole-ventricular IMRT limited irradiation to surrounding tissue in our cohort, a significant percentage of the brain received at least 12 Gy. This study suggests that there is a positive correlation between ventricular volume and the volume of brain parenchyma receiving at least 12 Gy with an important contribution from the boost phase of treatment.

Endoscopic Transsphenoidal Approach in Treatment of Germinomas of the Chiasmosellar Region

Introduction

Germinogenic central nervous system (CNS) tumors represent a heterogeneous group of tumors, constituting approximately 0.4% of all primary brain tumors. Removal of the tumor has no prognostic value. In "pure" primary germinomas of the CNS, the alpha-fetoprotein and human chorionic gonadotropin levels are within normal limits, and no specific biochemical tumor markers currently exist for this tumor type, making histological verification crucial for the choice of treatment tactics. When the tumor is located in the chiasmosellar region, one of the possible verification methods is endoscopic endonasal transsphenoidal biopsy.

Objective

The main objective of the study is to demonstrate the feasibility and safety of endoscopic transsphenoidal approach for histological verification of primary germinomas of the CNS with chiasmosellar localization.

Materials and Methods

The current study includes 13 patients with "pure" germinomas of the chiasmosellar region who underwent endoscopic endonasal surgical interventions with subsequent treatment according to the "Germinoma 2008" protocol.

Results

The extent of surgical intervention ranged from biopsy (4) to partial (5) and total (4) removal of the tumor. In all cases, histological verification of the diagnosis was achieved and none of the patients presented with cerebrospinal fluid leaks and/or meningitis in the postoperative period, allowing to evaluate endoscopic intervention in our patient series as safe and effective. Two out of 13 patients were lost to follow-up.

Conclusion

The endoscopic endonasal approach for histological verification and removal of chiasmosellar region germinomas is safe, and in some cases, less traumatic for the patient than transcranial and transventricular approaches.

Treatment outcomes based on radiation therapy fields for bifocal germinoma: Synchronous or disseminated disease?

Intracranial germinoma sometimes present as bifocal germinoma, and whether bifocal germinoma should be treated as a synchronous or disseminated disease remains unclear. This study aimed to determine the optimal treatment modality for bifocal germinoma. Patients with bifocal germinoma who received radiotherapy (RT) from March 1990 to August 2017 were included for analysis. A total of 21 patients were included. The median follow-up period was 76.2 months (range, 6.2-305.4 months). There were 17 patients who received cranio-spinal irradiation (CSI) with local RT; 3, whole ventricular RT (WVRT) with local RT; and 1, local RT only. Three recurrences occurred (1 patient each among those who underwent CSI, WVRT, and local RT). Recurrence in the patient who received CSI and who received WVRT occurred in the right thalamus and right frontal convexity, respectively. Meanwhile, the patient who received local RT showed not only a recurred lesion in the hypothalamus, but also cerebrospinal fluid seeding. For this patient, salvage CSI was performed and complete response was achieved after treatment. However, after 9 years and 6 months, he was diagnosed with glioblastoma and expired. As for toxicity, although 17 patients showed decrease in complete blood count levels during treatment, all patients recovered soon after treatment completion. Our findings suggest that bifocal germinoma may be considered as a disseminated disease when considering the patterns of failure according to RT fields. In addition, patients who received CSI showed low acute toxicity rates. However, further studies are necessary to confirm these findings.

Placental alkaline phosphatase levels in cerebrospinal fluid can have a decisive role in the differential diagnosis of intracranial germ cell tumors

OBJECTIVE

Placental alkaline phosphatase (PLAP) in CSF can provide a very high diagnostic value in cases of intracranial germ cell tumors (GCTs), especially in pure germinomas, to the level of not requiring histological confirmation. Unlike other tumor markers, reliable data analysis with respect to the diagnostic value of PLAP serum or CSF levels has not been available until now. This is the first systematic and comprehensive study examining the diagnostic value of CSF PLAP in patients with intracranial GCTs.

METHODS

From 2004 to 2014, 74 patients (average age 19.6 ± 10.6 years) with intracranial GCTs were evaluated using PLAP from their CSF and histological samples. Chemiluminescent enzyme immunoassay was utilized to measure CSF PLAP in the following tumor sites: pineal (n = 32), pituitary stalk, suprasellar (n = 16), basal ganglia (n = 15), intraventricular (n = 9), and cerebellar (n = 5) regions. In addition to classifying GCT cases, all patients underwent tumor biopsy for correlation with tumor marker data.

RESULTS

PLAP in combination with other tumor markers resulted in extremely high sensitivity and specificity of the diagnostic value of intracranial GCTs. Intracranial GCT cases were classified into 1) germinomas, both "pure" and syncytiotrophoblastic giant cell types (n = 38); 2) nongerminomatous GCTs, choriocarcinomas (n = 9) and teratomas (n = 4); and 3) nongerminomas, other kinds of tumors (n = 23). Consequently, all patients received chemoradiation therapy based on elevation of PLAP and the histopathological results. It was also speculated that the level of PLAP could show the amount of intracranial germ cell components of a GCT. PLAP was 100% upregulated in all intracranial germinoma cases. The absence of CSF PLAP proved that the tumor was not a germinoma.

CONCLUSIONS

The current study is the first systematic and comprehensive examination of the diagnostic value of the tumor marker PLAP in pediatric patients with intracranial GCT. Using the level of PLAP in CSF, we were able to detect the instances of intracranial germinoma with very high reliability, equivalent to a pathological diagnosis.

Redefining Ventricular Target Volume in Germinoma: Is Inclusion of Temporal Horns Necessary?

PURPOSE

We reviewed the outcomes of a retrospective germinoma cohort and analyzed radiation therapy plans to determine dosimetric differences for critical structures.

METHODS AND MATERIALS

Data from pediatric patients treated with photon radiation for intracranial germinoma were analyzed for clinical outcomes and dosimetry to critical structures, with particular interest in the temporal ventricular horns (TVHs). A consensus contour was generated for TVH-sparing ventricular clinical target volumes (CTVs) via deformable image registration.

RESULTS

Twelve and 10 patients had their TVHs included or excluded in their ventricular CTVs, respectively. All patients were living at the time of analysis. One patient relapsed in the fourth ventricle, which had been omitted from the radiation therapy field. Mean dose was significantly lower to the hippocampi (Δ = -578 cGy, P = .0016) and temporal lobes (Δ = -599 cGy, P = .0007) in the TVH-excluded cohort compared with those with TVHs included in the treatment field.

CONCLUSIONS

Exclusion of the TVHs from the CTV results in significant dose sparing to the hippocampi and temporal lobes. Clinical outcomes remain excellent with no deaths and no TVH failures. Exclusion of TVHs from the ventricular CTV in germinoma requires prospective study.

Treatment outcomes of intracranial germinoma: a retrospective analysis of 170 patients from a single institution

PURPOSE

To perform a retrospective analysis of patients with intracranial germinoma treated in our department to evaluate treatment outcomes and determine optimal treatment strategies.

METHODS

We reviewed the treatment outcomes of 170 patients with intracranial germinoma who were treated in our department from January 1996 to January 2017. The median patient age was 15 years old. Among the patients, 56 (33%) were pathologically diagnosed, and 114 (67%) were diagnosed clinically. Various radiation fields and doses were used. Cerebrospinal fluid (CSF) and serum beta-human chorionic gonadotropin (β-HCG) levels were examined before treatment in 114 patients. Endocrinological evaluation was performed in 141 patients before and after treatment. A total of 38 patients received chemotherapy prior to radiotherapy (RT). The median follow-up time was 64.5 months (range 4-260.5 months).

RESULTS

The 5- and 10-year overall survival (OS) rates were 94.5% and 91.3%, respectively. The relapse-free survival (RFS) rates at 5- and 10-years were 91.9% and 78.1%, respectively. Relapses occurred in 18 patients within 6 months-10 years. The spinal cord metastasis rate was 3.4% in patients with a localized lesion who did not receive spinal cord irradiation and 16.7% in patients with bifocal disease who were treated using whole ventricular irradiation (WVI) or whole brain radiotherapy (WBRT). Treatment failure did not occur in patients receiving chemoradiotherapy or in patients receiving three-dimensional conformal radiation therapy (3D-CRT)/intensity-modulated radiation therapy (IMRT). The RFS rate did not have a statistically significant correlation with the CSF/serum β-HCG level. After RT, 19.1% of the patients developed newly impaired pituitary function and required hormone replacement therapy.

CONCLUSIONS

WVI or WBRT+ primary boost (PB) is a sufficient irradiation field for localized intracranial germinoma, while patients with bifocal disease should undergo craniospinal irradiation (CSI), especially when treated with RT alone. CSF β-HCG is not a prognostic marker for intracranial germinomas. The treatment results of chemotherapy followed by reduced-dose RT are comparable to those of RT alone. IMRT is recommended for intracranial germinoma to improve the target volume accuracy and decrease the complications of RT.

Fast-developing fatal diffuse leptomeningeal dissemination of a pineal germinoma in a young child: a case report and literature review

BACKGROUND

Intracranial germinomas are uncommon and constitute less than 1% of all intracranial tumors. They usually arise in the midline of the brain, most commonly in the pineal region. Pineal germinomas tend to spread through the cerebrospinal fluid (CSF). However, pineal germinomas with fast-developing diffuse subarachnoid/leptomeningeal dissemination are extremely rare, especially in young children.

METHODS

The case of a 4-year-old boy with a pineal germinoma who died of diffuse subarachnoid/leptomeningeal dissemination 1 month after radiotherapy is reported. A PubMed search with specific key terms was used to review cases of pineal germinomas with metastasis.

RESULTS

The patient presented with a two-week history of worsening headache, visual disturbances and nonprojectile vomiting. Parinaud's sign was positive on physical examination. Head computed tomography (CT)/magnetic resonance imaging (MRI) revealed a lesion in the pineal region with eccentric calcification and obvious supratentorial hydrocephalus. Pineal germinoma was suspected. A ventriculoperitoneal (VP) shunt followed by focal radiotherapy ameliorated the headaches and visual disturbances. The patient was discharged home without further treatment due to financial difficulties. One month after discharge, he was readmitted due to worsening headache, vomiting and lethargy. MRI showed a decrease in the size of the pineal lesion but revealed a diffuse leptomeningeal enhancement including the sulcus, basal cistern, prepontine cistern, and supravermian cistern. The patient's condition deteriorated rapidly, and he died 26 hours after readmission. The characteristics of pineal germinomas with metastasis are reported based on a review of the literature.

CONCLUSIONS

Metastases in pineal germinomas predominately occur in adolescents or young adults, most commonly as spinal "drop metastases." Dissemination usually develops several years after the initial tumor diagnosis and has a relatively good clinical prognosis. However, fast widespread subarachnoid/leptomeningeal dissemination and sudden death may occur in a young child before salvage treatment, as in the presented case.

Secondary glioblastoma after treatment of intracranial germinoma - would radiation-only therapy still be safe? Case report

BACK GROUND

Intracranial germinomas are one of the most radiosensitive tumors and are curable by radiotherapy (RT) alone. RT-only therapy without chemotherapy is effective. But, as patients with germinoma can expect long-term survival, the adverse effects of RT and late sequelae in survivors are of most concern. So, recently, standard treatment protocol of combination with chemotherapy and reduced dose of RT could be widely acceptable.

CASE PRESENTATION

We report a patient with germinoma who developed RT-induced glioblastoma. He was diagnosed as biopsy-proven germinoma at the age of 12. Postoperatively, he underwent RT alone without chemotherapy and remained free of tumor without recurrence during long-term follow up. However, after almost 20 year, he developed RT-induced glioblastoma.

CONCLUSIONS

Although RT has the highest priority among treatments on intracranial germinomas, RT-only therapy with full dose for germinoma can have delayed severe complications. So, chemotherapy prior to reduced dose RT is more desirable.

Cognitive Profile of Children With Intracranial Germ Cell Tumor According to Tumor Location

PURPOSE

The purpose of this study was to evaluate the long-term cognitive sequelae and to describe the neuropsychological profile of patients with intracranial germ cell tumors according to tumor location (pineal or suprasellar site).

PATIENTS AND METHODS

Forty-five children treated at Gustave Roussy between 1991 and 2010 were assessed with neuropsychological tests to measure IQ, memory, visuospatial, motor, and executive skills at a mean delay of 4.2 years after diagnosis. All patients have received chemotherapy associated with surgery in 17 cases. Thirty-nine patients received, radiotherapy (focal 27, focal plus ventricles 8, craniospinal 4). Twenty-three patients had 2 IQ assessments with a mean delay of 4.1 years between the first and second.

RESULTS

Full scale IQ was preserved, with higher verbal IQ than other IQ indexes. Visuospatial, fine-motor, and executive difficulties were present in a significant proportion of patients. Visuospatial and fine-motor deficits were significantly associated with oculomotor difficulties, more present in the pineal than in the suprasellar group. No cognitive decline was observed between the first and the second IQ assessment.

CONCLUSIONS

Overall cognitive abilities were preserved in children treated for central nervous system germ cell tumor.

Proton therapy for pediatric malignancies: Fact, figures and costs. A joint consensus statement from the pediatric subcommittee of PTCOG, PROS and EPTN

Radiotherapy plays an important role in the management of childhood cancer, with the primary aim of achieving the highest likelihood of cure with the lowest risk of radiation-induced morbidity. Proton therapy (PT) provides an undisputable advantage by reducing the radiation 'bath' dose delivered to non-target structures/volume while optimally covering the tumor with tumoricidal dose. This treatment modality comes, however, with an additional costs compared to conventional radiotherapy that could put substantial financial pressure to the health care systems with societal implications. In this review we assess the data available to the oncology community of PT delivered to children with cancer, discuss on the urgency to develop high-quality data. Additionally, we look at the advantage of combining systemic agents with protons and look at the cost-effectiveness data published so far.

Practice patterns and survival outcomes of intracranial germinoma: an analysis of the National Cancer Database

The goal of the study is to examine the practice pattern and survival outcome of adult and pediatric patients with intracranial germinoma. Patients from the National Cancer Database (NCDB) brain tumor registry between the years 2004-2014 with intracranial germinoma were extracted for analysis. Patients who had distant metastasis, received no treatments, or only surgery/chemotherapy alone were excluded. An age cutoff of > 21 years old was used to define the pediatric population. Patients were stratified by the treatments radiation therapy alone (RT) and chemotherapy followed by radiation therapy (C + RT). 445 patients with intracranial germinoma meeting our inclusion criteria were identified. Of the adult patients, 65.7% received RT and 34.3% received C + RT, compared to the pediatric patients, where 31.8% received RT and 68.2% received C + RT. Those patients who received C + RT had a lower radiation dose compared to the RT group (p < 0.001). The 5 and 10 year overall survival (OS) for the entire cohort was 92.6 and 87.9%, respectively. Univariate analysis demonstrated improved OS with younger age, private insurance, C + RT treatment, and pediatric patients. Only age and insurance type remained significant on multivariate analysis. The 5 year OS was 92.6% (RT) versus 97.2% (C + RT) (p = 0.307) and 83.4% (RT) versus 95.4% (C + RT) (p = 0.122) in the pediatric and adult patients, respectively. There is a higher use of C + RT with an accompanied reduction in RT dose in the treatment of intracranial germinoma. There is no difference in survival between the treatment approaches of RT or C + RT in the NCDB patient cohort.

Craniospinal irradiation using helical tomotherapy for central nervous system tumors

The aim of this study was to describe early and late toxicity, survival and local control in 45 patients with primary brain tumors treated with helical tomotherapy craniospinal irradiation (HT-CSI). From 2006 to 2014, 45 patients with central nervous system malignancies were treated with HT-CSI. The most common tumors were medulloblastoma in 20 patients, ependymoma in 10 patients, intracranial germinoma (ICG) in 7 patients, and primitive neuroectodermal tumor in 4 patients. Hematological toxicity during treatment included leukopenia Grades 1-4 (6.7%, 33.3%, 37.8% and 17.8%, respectively), anemia Grades 1-4 (44.4%, 22.2%, 22.2% and 0%, respectively) and thrombocytopenia Grades 1-4 (51.1%, 15.6%, 15.6% and 6.7%, respectively). The most common acute toxicities were nausea, vomiting, fatigue, loss of appetite, alopecia and neurotoxicity. No Grade 3 or higher late toxicity occurred. The overall 3- and 5-year survival rates were 80% and 70%, respectively. Survival for the main tumor entities included 3- and 5-year survival rates of 80% and 70%, respectively, for patients with medulloblastoma, 70% for both in patients with ependymoma, and 100% for both in patients with ICG. Relapse occurred in 11 patients (24.4%): 10 with local and 1 with multifocal relapse. One patient experienced a secondary cancer. M-status and the results of the re-evaluation at the end of treatment were significantly related to survival. Survival after HT-CSI was in line with the existing literature, and acute treatment-induced toxicity resolved quickly. Compared with conventional radiotherapy, HT offers benefits such as avoiding gaps and junctions, sparing organs, and better and more homogeneous dose distribution and coverage of the target volume.

Recent advances in molecular biology and treatment strategies for intracranial germ cell tumors

BACKGROUND

Intracranial germ cell tumors (IGCTs) are a group of rare pediatric brain tumors which include various subtypes. The current understanding of the etiology of the tumors and their optimal management strategies remain controversial.

DATA SOURCES

The data on IGCTs were collected from articles published in the past 20 years, and the origin and etiology of IGCTs at molecular level as well as the relative roles of varied treatment strategies in different prognosis groups according to Matsutani's classification were reviewed.

RESULTS

Recent cellular and molecular evidence suggests that IGCTs may arise from the transformation of endogenous brain cells; and findings in the molecular characterization of IGCTs suggest roles of CCND2, RB1, and PRDM14 in the pathogenesis of IGCTs and identify the KIT/RAS and AKT1/mTOR pathways as potential therapeutic targets in future. According to Matsutani's classification of IGCTs, the good prognosis group includes both germinomas and mature teratomas. For germinomas, both radiation alone and reduced-dose radiotherapy in combination with adjuvant chemotherapy are effective, while complete surgical excision is recommended for mature teratomas. In the intermediate prognosis group, immature teratoma has been successfully treated with gamma knife surgery. However, for intermediate prognosis IGCTs other than immature teratomas, gross total resection with adjuvant chemotherapy and radiotherapy or gamma knife surgery may be necessary to achieve cure. In the poor prognosis group, survival outcomes are unsatisfactory, and complete surgical resection combined with more intensive chemotherapy and radiotherapy remains the best available treatment option at this time.

CONCLUSIONS

IGCTs should be strictly classified according to their pathological categories before administering pathology-specific treatments. Although open microsurgical excision is the traditional surgical strategy for IGCTs, recent publications also support the role of endoscopic surgical options for pineal region IGCTs.

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.

Determining an Optimal Cutoff of Serum β-Human Chorionic Gonadotropin for Assisting the Diagnosis of Intracranial Germinomas

Background

Beta (β)-human chorionic gonadotropin (β-HCG) is used to confirm the diagnosis and plan treatment of intracranial germinomas. However, the cutoff values of serum β-HCG in diagnosis of intracranial germinomas reported in the literature are inconsistent. To establish an appropriate cutoff value of serum β-HCG for diagnosis of intracranial germinomas, we retrospectively reviewed the records of intracranial tumor patients who received serum β-HCG and α-fetoprotein (AFP) tests for diagnostic purposes at our hospital from 2005 to 2014.

Methods

A total of 93 intracranial germinomas and 289 intracranial non-germ cell tumors were included in this study. Receiver operating characteristic (ROC) analysis was used to evaluate the sensitivity and specificity of 3 cutoffs (0.1, 0.4, and 0.5 mIU/mL) for diagnosing intracranial germinomas. The serum β-HCG level of intracranial germinoma patients was further analyzed to investigate the effect of metastasis status and tumor location on serum β-HCG level.

Results

The area under the ROC curve was 0.81 (P < .001), suggesting β-HCG is an effective marker. Of the 3 cutoff values, 0.1 mIU/mL possessed a highest sensitivity (66.67%) and good specificity (91%). Although there was no β-HCG level difference between metastatic and non-metastatic intracranial germinoma patients, the diagnostic rate of metastatic neurohypophyseal germinomas was significantly higher than that of its non-metastatic counterpart (P < .05), implying that the location of the germinoma might need to be considered when β-HCG is used as a marker to predict metastasis.

Conclusions

Determining an optimal cutoff of serum β-HCG is helpful for assisting the diagnosis of intracranial germinoma.

Gamma knife radiosurgery (GKRS) for pineal region tumors: a study of 147 cases

Background

The purpose of this study is to evaluate the effectiveness of gamma knife radiosurgery (GKRS) in the treatment of pineal region tumors (PRTs).

Methods

We retrospectively reviewed 147 cases of PRTs primarily treated with GKRS at our hospital between 1999 and 2009. Mean follow-up time was 67 months (range 60.5–100.1). The local tumor control rates (LTCRs) and overall survival rates were calculated to evaluate the results of the GKRS treatment.

Results

At 2 months after GKRS, tumor volume was significantly reduced in 91 cases (61.9 %). At 6 months, average tumor volume was 4.2 cm³ as compared to 8.47 cm³ before GKRS. By 1 year after GKRS, the tumor completely disappeared in 57 patients. Fourteen patients underwent second treatment, and one patient had third treatment. The overall survival rates were 72.1 % at 3 years and 66.7 % at 5 years for all patients and 62.4 % at 3 years and 54.5 % at 5 years for germ cell tumors (GCTs). The LTCRs were 94.30 % at 3 years and 90.80 % at 5 years for all patients and 88.00 % at 3 years and 77.27 % at 5 years for GCTs.

Conclusions

GKRS is an effective and safe modality that can be widely used to PRTs as the primary therapy.

A comparative study of the extent of cerebral microvascular injury following whole-brain irradiation versus reduced-field irradiation in long-term survivors of intracranial germ cell tumors

BACKGROUND AND PURPOSE

Radiation-induced cerebral cavernous malformation reflects post-irradiation impairment of cerebral microcirculation. Our purpose was to determine effects of radiation field size and dose on the extent of developing cavernous malformations in long-term survivors of intracranial germ cell tumors (GCTs).

METHODS

The study involved 34 patients with a history of intracranial GCTs treated with either whole-brain or reduced-field irradiation and undergoing magnetic resonance (MR) imaging with a mean follow-up of 18.5 years. The number of cavernous malformations on T2*-weighted MR images between whole-brain and reduced-field irradiation groups as well as between high- (50.2 Gy) and low-dose (24.4 Gy) fields were compared.

RESULTS

A total of 235 cavernous malformation lesions were observed in 32 of 34 patients (94.1%). The mean number of lesions was 2.3 times as high in the whole-brain group as in the reduced-field group (P = 0.00296). The number of lesions in high-dose fields was significantly larger than in low-dose (P < 0.000001) or untreated fields (P < 0.001).

CONCLUSION

Radiation field size and dose were positively associated with the number of cavernous malformations developed. Cavernous malformations detected on MR imaging can be used as a surrogate marker for microvascular injury following intracranial irradiation in long-term cancer survivors.

Central nervous system germ cell tumors: an update

PURPOSE OF REVIEW

Malignant germ cell tumors in the central nervous system are rare and not well known because they occur mainly in adolescents, an age in which patients are dispersed in adult and pediatric wards. Their biology starts to be unraveled by high-throughput genomics and their treatment is now well defined thanks to international studies, including patients from childhood through adulthood.

RECENT FINDINGS

Chemotherapy gained definitively a role apart from radiotherapy in order to improve tumor control in secreting neoplasms, but also to decrease the volume or dose of radiation therapy in germinomas. Neurocognitive outcome remains good with some disparities because of tumor location, patients with pineal tumors being less impaired than those with supratentorial malignant germ cell tumors. Alterations in the KIT/RAS as well as in the mTOR/AKT pathways have been frequently reported and could represent interesting opportunities to introduce targeted therapies in these neoplasms.

SUMMARY

Diagnosis and treatment of malignant germ cell tumor of the brain are now well established within experienced multidisciplinary teams taking care of adolescents and young adults. The prognosis of secreting tumors has not yet reached the excellent results obtained for germinomas but aggressive chemotherapy including high-dose chemotherapy with stem-cell support may contribute to improve their outcome. The role of targeted therapies has yet to be determined in view of the recently described molecular findings.

Understanding the Treatment Strategies of Intracranial Germ Cell Tumors: Focusing on Radiotherapy

Intracranial germ cell tumors (ICGCT) occur in 2-11% of children with brain tumors between 0-19 years of age. For treatment of germinoma, relatively low radiation doses with or without chemotherapy show excellent 10 year survival rate of 80-100%. Past studies showed that neoadjuvant chemotherapy combined with focal radiotherapy resulted in unacceptably high rates of periventricular tumor recurrence. The use of generous radiation volume which covers the whole ventricular space with later boost treatment to primary site is considered as standard treatment of intracranial germinomas. For non-germinomatous germ cell tumors (NGGCT), 10-year overall survival rate is still much inferior than that of intracranial germinoma despite intensive chemotherapy and high-dose radiotherapy. Craniospinal radiotherapy combined with cisplatin-based chemotherapy provides the best treatment outcome for NGGCT; 60-70% of overall survival rate. There is a debate on the surgical role whether surgery can contribute to improved treatment outcome of NGGCT when added to combined chemoradiotherapy. Because higher dose of radiotherapy is required for treatment of NGGCT than for germinoma, it is tested whether whole ventricular irradiation can replace craniospinal irradiation in intermediate risk group of NGGCT to minimize radiation-related late toxicity in the recent studies. To minimize the treatment-related neural deficit and late sequelae while maintaining long-term survival rate of ICGCT patients, optimized administration of chemotherapy and radiotherapy should be selected. Use of technically upgraded radiotherapy modalities such as intensity-modulated radiotherapy or proton beam therapy is expected to bring an improved neurocognitive outcome with longitudinal assessment of the patients.

Results of sequential chemoradiotherapy for intracranial germinoma

PURPOSE

To evaluate the efficacy of sequential chemoradiotherapy (CRT) for intracranial germinoma by long-term follow-up.

MATERIALS AND METHODS

We retrospectively evaluated 23 consecutive intracranial germinoma patients without spinal dissemination, who had been treated by sequential CRT. All patients except for one were biopsied or surgically resected before treatment and all patients received both cranial and spinal magnetic resonance imaging. Three cycles of induction chemotherapy composed of etoposide and platinum agents were administered. The prescription of radiotherapy was 24 Gy per 12 fractions. No patients received spinal irradiation.

RESULTS

All patients accomplished CRT and achieved complete remission. No severe acute and late toxicities were observed. Median follow-up time was 11.8 years. The 5- and 10-year overall survival rates were 100 and 100 %, and relapse-free survival rates were 96 and 89 %, respectively. Three patients developed intracranial recurrence and all of them were successfully salvaged by additional CRT. All patients were alive without disease at final follow-up.

CONCLUSION

Treatment of 24 Gy of sequential CRT for intracranial germinoma might be promising as an alternative to radiotherapy alone. Spinal irradiation may not be necessary for patients who had no spinal dissemination and who were treated with CRT.

Successful surgical treatment of mature teratoma arising from the sella

Mature teratoma of the pituitary-hypothalamic region is rarely reported in the literature. In this article, we present a 13-year-old girl with clinical and radiological findings that were initially considered as germinoma. However, histological examinations disclosed a mature teratoma. This case highlights that the radiation-induced cerebral edema caused acute hydrocephalus. The mature teratoma is not radiosensitive, and the most appropriate treatment is direct surgery.

Predictors of long-term survival following postoperative radiochemotherapy for pathologically confirmed suprasellar germ cell tumors

The aim of this study was to evaluate the predictors of long-term survival following postoperative therapy for suprasellar germ cell tumors (GCTs). A total of 23 patients with pathologically confirmed suprasellar GCTs were reviewed between April, 1987 and October, 2008. The predictors were identified with a univariate Cox proportional hazards model and the results were used to group patients according to outcome. The overall survival (OS) and progression-free survival (PFS) rates for the good- and poor-prognosis two groups were estimated with Kaplan-Meier analysis, with log-rank tests used to assess differences between the groups. The OS rate for all patients was 82.6% at 5 and 72.9% at 10 years. Lesion size (2-4 vs. >4 cm) and pathological type (pure germinoma vs. mixed GCT) were the only significant predictors of OS (P<0.05). The OS rate for the good-prognosis group was 92.9% at both 5 and 10 years, whereas the corresponding rates for the poor-prognosis group were 66.7 and 40.0%, respectively (P=0.020). The PFS rate for the good-prognosis group was 92.9% at 5 and 85.7% at 10 years, whereas the corresponding PFS rates for the poor-prognosis group were 44.4 and 33.3%, respectively (P=0.007). Lesion size and histology predicted outcome following postoperative therapy for suprasellar GCT. Therefore, pathological diagnosis is recommended whenever possible, as histology may dictate the choice of treatment.

Pretreatment diagnosis of suprasellar papillary craniopharyngioma and germ cell tumors of adult patients

BACKGROUND AND PURPOSE

Suprasellar papillary craniopharyngiomas and germ cell tumors in adults share some clinical and imaging similarities but have different therapeutic strategies and outcomes. This study aimed to evaluate the pretreatment diagnosis of these 2 tumors to improve the therapeutic outcome.

MATERIALS AND METHODS

We retrospectively enrolled 18 adults with papillary craniopharyngiomas and 17 with germ cell tumors. The MR imaging findings were evaluated, including signal change and anatomic extension. The medical records were reviewed to collect clinical findings, management, and outcomes.

RESULTS

The clinical findings of papillary craniopharyngiomas versus germ cell tumors were as follows: age: 46 ± 13.9 years versus 23 ± 7.1 years (P < .0001); diabetes insipidus: 2/18 (11%) versus 11/17 (65%) (P = .001); recurrence 13/16 (81%) versus 4/17 (24%) (P = .0031). The MR imaging findings of papillary craniopharyngiomas versus germ cell tumors were as follows—pituitary stalk thickening: 1.6 ± 0.4 mm versus 5.4 ± 4.2 mm (P < .0001); vertical infundibular extension: 1/18 (6%) versus 16/17 (94%) (P < .0001); sagittal spheric shape: 17/18 (94%) versus 1/17 (6%) (P < .0001); diffusion restriction: 1/17 (6%) versus 8/12 (67%) (P = .0009).

CONCLUSIONS

Younger age, diabetes insipidus, MR imaging characteristics of restricted diffusion, and vertical infundibular extension favor the diagnosis of germ cell tumors. Spheric shape without infundibular infiltration provides clues to papillary craniopharyngiomas, which originate from the pars tuberalis and are located outside the third ventricle. We suggest that suprasellar germ cell tumor is possibly an intraventricular lesion. Appropriate treatment planning can be initiated according to the diagnosis and anatomic location.

Pure germinomas of the central nervous system: treatment strategies and outcomes

To evaluate the role of chemotherapy and radiation therapy in the treatment of pure germinomas of the central nervous system (CNS). We reviewed a historical cohort of 79 patients between the ages of 3-35 years who received definitive treatment for newly diagnosed, pure CNS germinoma between 1985 and 2010 at the University of California, San Francisco (UCSF). Median age at diagnosis was 15 years (interquartile range, IQR 12-20 years) and 61 (77.2 %) patients were male. Median follow-up for the cohort was 111.1 months (IQR 45.7-185.1 months). Five-year PFS rate was 86.4 % (95 % CI 76.1-92.4) and 5 year OS rate was 93.0 % (95 % CI 84.1-97.1). Median PFS was 104.6 months (IQR 41.4-170.1 months). Fourteen patients progressed and 8 died of their disease. Patients who received focal irradiation (XRT) and chemotherapy had a significantly higher rate of progression compared to those who received whole brain irradiation (WBI) or whole ventricle irradiation (WVI). Three of 8 patients had a PR to chemotherapy and received focal XRT progressed whereas only 1 of 9 patients who had a CR to chemotherapy who went on to receive focal XRT progressed. Elevation of hCGβ > 50 mIU/ml was not significantly associated with disease progression (HR 5.64, 95 % CI 0.97-32.7, p = 0.054). Patients treated with WBI or WVI with or without chemotherapy achieve better disease control compared to patients treated with focal XRT + chemotherapy.

Long-term follow-up and quality of life in patients with intracranial germinoma

Intracranial germinomas are fairly rare tumors occurring mostly in children or young adults with a comparatively good prognosis. Radiation is the preferred treatment of choice for this diagnosis. It has been thoroughly studied to what extent radiation doses and fields can be limited in order to avoid side effects in these young patients. The role of chemotherapy remains unclear, whereas surgery is limited to biopsy for proof of histology. Regarding the good overall survival rate, quality of life is a significant aspect to consider in these patients. We present a single institution analysis of patients with intracranial germinoma and analyze the long-term outcome with special regard to quality of life. Thirty-three patients with intracranial germinomas were analyzed by chart review, telephone interview, and neurological assessment. Additionally, a survey on quality of life was performed. The 10-year overall survival rate was 82.1 % at a mean follow-up of 141 (22-306) months. Three quarters (76 %) of the patients reached a favorable neurological outcome on the Modified Rankin Scale (mRS 0-2). However, the self-reported quality of life was significantly worse in germinoma patients compared with a healthy control group (p < 0.001). Surgical resection of the tumor led to no improvement regarding overall survival, neurological outcome, and quality of life. In terms of cognitive functioning, patients with tumor resection were significantly more impaired than biopsied patients (p = 0.04). Although germinomas are efficiently treatable tumors, the restrictions in quality of life in these often young patients are considerable, including financial difficulties. There seems no justification for tumor resection in newly diagnosed cases suspicious for germinoma as the cognitive outcome is worse than in biopsied patients, and there is no effect on overall survival.

Current concepts and future strategies in the management of intracranial germinoma

Radiation therapy is the backbone in the management of intracranial germinoma. In localized disease chemotherapy followed by whole brain irradiation is the present standard providing cure rates in excess of 90%. Craniospinal irradiation alone in metastatic disease provides equally excellent outcome. Chemotherapy is able to convert macroscopic to microscopic disease permitting a dose reduction to the tumor site and possibly the ventricular system and is investigated in prospective trials. Chemotherapy alone cannot replace radiotherapy as sole treatment. Whole-ventricular radiotherapy followed by a boost to tumor site without chemotherapy might be feasible. New treatment technologies such as intensity-modulated radiotherapy or proton therapy permit a dose reduction to non-target brain. Data on functional outcome are conflicting and based on small heterogeneous series only mandating prospective investigations.

Second primary brain tumors following cranial irradiation for pediatric solid brain tumors

PURPOSE

We describe our institution's experience with seven patients who developed second brain tumors following cranial irradiation.

METHODS

The median age at first irradiation was 8 years (range, 3-20 years). Initial diagnoses were two cases of germinoma, one non-germinomatous germ cell tumor (NGGCT), three cases of medulloblastoma, and one pineal gland tumor (pathology undetermined). All patients received craniospinal irradiation followed by local boost and the median dose to the initial tumor area was 54.0 Gy (range, 49.8-60.6 Gy). Four patients (two medulloblastomas, one germinoma, and one NGGCT) received chemotherapy.

RESULTS

Second brain tumors were diagnosed a median of 114 months (range, 64-203) after initial radiation. Pathologic diagnoses were one glioblastoma, two cases of anaplastic astrocytoma, one medulloblastoma, one low-grade glioma, one high-grade glial tumor, and one atypical meningioma. Five patients underwent surgical resection with subsequent radiotherapy. One anaplastic astrocytoma patient received chemotherapy only following stereotactic biopsy. The meningioma patient was alive 32 months after total resection and radiosurgery for subsequent recurrences. Six patients died within 18 months and most deaths were due to disease progression.

CONCLUSIONS

Most patients diagnosed with second brain tumors had received high-dose, large-volume radiotherapy with chemotherapy at a young age. Further studies are required to determine the relationship between radiotherapy/chemotherapy and the development of secondary brain tumors.

Feasibility of dasatinib in children and adolescents with new or recurrent central nervous system germinoma

Germinomas and embryonal carcinomas are central nervous system (CNS) germ cell tumors (GCT) that may overexpress the proto-oncogene c-KIT, a receptor tyrosine kinase, of which dasatinib is a potent inhibitor. This retrospective review presents the feasibility and tolerability of dasatinib administration in select patients with CNS germinoma. Between November 2008 and April 2010, six patients with newly diagnosed (n = 3) or recurrent (n = 3) CNS GCT were treated in an effort to avoid irradiation and/or delay recurrence. The daily doses administered were 100-170 mg/m(2) with mostly grade 1-2 toxicities. Dasatinib may play a role in future treatment strategies for CNS GCT.

Factors affecting functional outcomes in long-term survivors of intracranial germinomas: a 20-year experience in a single institution

OBJECT

Radiation monotherapy-prophylactic craniospinal or whole-brain irradiation paired with a radiation boost to the primary tumor-is the standard treatment for intracranial germinomas at the authors' institution. The authors assessed long-term outcomes of patients with germinoma who underwent therapy and identified factors affecting them.

METHODS

The authors retrospectively analyzed data obtained in 46 patients (35 males and 11 females, age 5-43 years at diagnosis) who had been treated for intracranial germinomas between 1990 and 2009 at the authors' institution. Thirty patients had germinomas in localized regions and 16 in multiple regions. Thirty-eight patients (83%) underwent radiotherapy alone (craniospinal irradiation in 32 and whole-brain irradiation in 6). Seven patients underwent radiochemotherapy and 1 underwent chemotherapy alone. The mean radiation doses for the whole brain, spine, and primary tumor site were 26.9, 26.6, and 49.8 Gy, respectively. The median follow-up period was 125 months.

RESULTS

The 10-year overall and recurrence-free survival rates were 93.3% and 89.3%, respectively. None of the 38 patients who received radiation monotherapy developed a recurrent lesion, whereas 1 of 7 who underwent radiochemotherapy and the 1 patient who underwent chemotherapy had a recurrent lesion. Of the entire population, 26 patients required hormone replacement therapy, 2 had short stature, and 1 developed a radiation-induced meningioma. Seventeen of the 25 childhood- or adolescent-onset patients were 19 years or older at the latest follow-up visit, 15 of whom graduated from senior high school, and only 2 of whom graduated from college. Of 34 patients who were 19 years or older at the latest visit, 4 were students, 18 worked independently, 4 worked in sheltered workplaces, and 8 were unemployed. Of the 34 patients, 4 got married after the initial treatment, 3 of whom had children. There were 8 patients (17%) with low postoperative Karnofsky Performance Scale (KPS) scores that were significantly associated with impaired neurocognitive functions, severe surgical complications, and neurological impairments. In 10 of the 46 patients, KPS scores at the latest visit were lower than their postoperative KPS scores. These decreases in KPS scores were significantly correlated with a delayed decline in neurocognitive functions in childhood-onset patients and a postoperative impairment of neurocognitive functions in patients with adolescent- or adult-onset germinoma.

CONCLUSIONS

No tumor recurrence occurred in germinoma patients treated with the authors' radiation monotherapy, which appears to be effective enough to cure the tumor. Brain damage caused by tumors themselves and surgical complications were found to adversely affect functional outcomes in patients regardless of their age. Although radiotherapy rarely caused late adverse effects in patients with adolescent- or adult-onset, in some childhood-onset lesions, the radiation seems to carry the risk of neurocognitive dysfunctions, which are attributable to late adverse effects. Accordingly, treatments for germinoma patients should be selected according to a patient's age and the extent of the tumor and with particular care to avoid surgical complications.

Primary intracranial germ-cell tumors in adults: a practical review

Primary intracranial germ-cell tumors are rare tumors primarily of adolescence, and literature on this disease in adults is scarce. The available evidence on intracranial germ-cell tumors is reviewed with a focus on adult patients whenever possible, and used to make suggestions for diagnosis and treatment. Diagnostic and treatment algorithms were developed to provide an evidence-based backbone to base treatment on in adult patients with a (suspected) primary intracranial germ-cell tumor.

Memory Disorders in Children With Central Nervous System Germ Cell Tumors

Memory disorders in children and adolescents with brain tumors are rare, but devastating to social, academic, and vocational development. Many pediatric patients with intracranial germ cell tumors (GCTs) complain of memory difficulties. This study investigated memory across a series of GCT patients. A total of 33 GCT patients were retrospectively examined for diagnosis, imaging results, intelligence quotient, treatment variables, evidence of increased intracranial pressure at diagnosis, and memory. The incidence of amnesia in GCT patients was 55%. Memory disturbance could not be predicted by intelligence quotient, treatment, location of lesion, or hydrocephalus at diagnosis. The high incidence of memory deficits in GCT patients suggests a risk to memory in patients with GCT. Formal memory assessment should be considered in all patients with central nervous system GCTs. Specific counseling and planning to assist in adjustment and to ensure safety should be considered standard care for those with memory deficits. The nurse should be instrumental in facilitating understanding of this specific injury in the brain tumor population.

Medulloblastoma/Primitive neuroectodermal tumor and germ cell tumors: the uncommon but potentially curable primary brain tumors

This article presents an overview of medulloblastomas, central nervous system primitive neuroectodermal tumors, and germ cell tumors for the practicing oncologist. Discussion includes the definition of these tumors, histopathologic findings, molecular and genetic characteristics, prognoses, and evolution of treatment.