The management of central neurocytoma: radiosurgery

Long-term outcomes of central neurocytoma - an institutional experience

INTRODUCTION

Central Neurocytoma (CN) is a rare, WHO grade 2 brain tumor that predominantly affects young adults. Gross total resection (GTR) is often curative for CNs, but the optimal treatment paradigm including incorporation of RT, following subtotal resection (STR) and for scarcer pediatric cases has yet to be established.

METHODS

Patients between 2001 and 2021 with a pathologic diagnosis of CN were reviewed. Demographic, treatment, and tumor characteristics were recorded. Recurrence free survival (RFS) and overall survival (OS) were calculated according to the Kaplan Meier-method. Post-RT tumor volumetric regression analysis was performed.

RESULTS

Seventeen adults (≥ 18 years old) and 5 children (< 18 years old) met the criteria for data analysis (n = 22). With a median follow-up of 6.9 years, there was no tumor-related mortality. Patients who received STR and/or had atypical tumors (using a cut-off of Ki-67 > 4%) experienced decreased RFS compared to those who received GTR and/or were without atypical tumors. RFS at 5 years for typical CNs was 67% compared to 22% for atypical CNs. Every pediatric tumor was atypical and 3/5 recurred within 5 years. Salvage RT following tumor recurrence led to no further recurrences within the timeframe of continued follow-up; volumetric analysis for 3 recurrent tumors revealed an approximately 80% reduction in tumor size.

CONCLUSION

We provide encouraging evidence that CNs treated with GTR or with RT after tumor recurrence demonstrate good long-term tumor control.

Radiotherapy for central neurocytoma: A multicentric retrospective study in France

PURPOSE

Neurocytomas represent 0.25 to 0.5% of primary brain tumours and are mainly found in young adults. These tumours have neuronal differentiation. The cornerstone treatment is neurosurgery. The efficacy of other therapies, including radiotherapy, is still unclear. The objective of this study was to evaluate the management of central neurocytomas and the role of radiotherapy.

MATERIALS AND METHODS

All adult patients (age 18 years or older) newly diagnosed with a histologically confirmed neurocytoma between 2006 and 2015 in France were included.

RESULTS

One hundred and sixteen patients were diagnosed with a central neurocytoma during the study period. All patients underwent surgical resection, and six received adjuvant radiotherapy. Eleven patients received radiotherapy due to progression. After a median follow-up of 68.7 months, local failure occurred in 29 patients. The 5-year local control rate was 73.4%. According to univariate analysis, marker of proliferation Ki67 index greater than 2% (hazard ratio [HR]: 1.48; confidence interval [CI]: 1.40-1.57; P=0.027) and subtotal resection (HR: 8.48; CI: 8.01-8.99; P<0.001) were associated with an increase in local failure. Gross total resection was associated with a higher risk of sequelae epilepsy (HR: 3.62; CI: 3.42-3.83; P<0.01) and memory disorders (HR: 1.35; CI: 1.07-1.20; P<0.01). Ten patients (8.6%) died during the follow-up. The 10-year overall survival rate was 89.0%. No prognostic factors for overall survival were found.

CONCLUSION

The analysis showed that patients who underwent subtotal surgical resection, particularly when the tumour had a Ki67 index greater than 2%, had an increased risk of local recurrence. These patients could benefit from adjuvant radiotherapy.

Gamma Knife radiosurgery for central neurocytoma: a quantitative systematic review and metanalysis

Central neurocytomas (CN) are rare tumors within the central nervous system. Originating from the septum pellucidum and subependymal cells, they are typically found in the third and lateral ventricles. For this reason, they may lead to hydrocephalus and increased intracranial pressure. CNs are generally benign lesions that exhibit locally aggressive behavior and a high recurrence rate. Complete surgical resection is the preferred treatment; however, due to their anatomical location, this is often not feasible. Based on these findings, Gamma Knife radiosurgery (GKRS) has been introduced for managing both residual and recurrent tumors and as an initial therapy in selected cases. This study aimed to systematically review the available knowledge regarding GKRS for CN. A systematic investigation of the scientific literature was undertaken through an exhaustive search across prominent databases, including PubMed, Web of Science, and Google Scholar, by employing precise MeSH terms such as "Central neurocytoma," "Radiosurgery," "Gamma Knife," and "Stereotactic Radiosurgery." A comprehensive quantitative systematic review and meta-analysis were meticulously conducted, focusing on cases of CN treated with GKRS for a thorough evaluation of outcomes and efficacy. Seventeen articles, including 289 patients, met the inclusion criteria. Random effects meta-analysis estimates for disease control and local tumor control were 90% (95% CI 87-93%; I2 = 0%, p < 0.74) and 94% (95% CI 92-97%; I2 = 0%, p < 0.98), respectively. When considering only studies with at least 5 years of follow-up, progression-free survival was 89% (95% CI 85-94%; I2 = 0.03%, p < 0.74). The mean clinical control rate was 96%. This systematic review and meta-analysis confirmed the safety and efficacy of GKRS in managing CN.

The role of single fraction Gamma Knife radiosurgery for intraventricular central neurocytomas and the utility of F-18 fluroethyltyrosine: two case reports

BACKGROUND

Primary treatment of central neurocytomas is surgical resection. Gamma Knife surgery is considered a valuable therapeutic option in case of residual (after subtotal resection) or recurrent central neurocytomas. Here, we focused on the role of F-18 fluroethyltyrosine as a marker to document tumor progression after initial resection, in the context of an atypical central neurocytoma. We also describe MIB-1's role in evaluating therapeutic decision-making.

CASE PRESENTATION

Two patients with central neurocytomas were treated by Gamma Knife surgery in our center. The first case (31-year-old Caucasian male) had atypical central neurocytoma. Four and a half years after surgical resection, magnetic resonance imaging and F-18 fluroethyltyrosine documented clear progression of residual central neurocytoma, further treated by Gamma Knife surgery (18 Gy at 50%, target volume 1.4 cc, and prescription isodose volume 1.8 cc). The initial post-Gamma Knife surgery clinical course was uneventful, with progressive volumetric reduction of residual tumor up to 4.5 years, when out-of-field recurrence was suspected and confirmed by local F-18 fluroethyltyrosine hyperactivity. Second single-fraction Gamma Knife surgery was performed (18 Gy at 50%, target volume 0.49 cc, prescription isodose volume 0.72 cc). The second (32-year-old Caucasian female) had previous subtotal resection and typical central neurocytoma. Seven years later, she had residual tumor progression. Single-fraction Gamma Knife surgery was performed (16 Gy at 50% isodose line, target volume 1.7 cc, and prescription isodose volume 2.5 cc). Last follow-up showed tumor volume reduction. Follow-up magnetic resonance imaging showed important volumetric reduction of both treated lesions.

CONCLUSIONS

In atypical central neurocytomas, F-18 fluroethyltyrosine could be used as postoperative examination to detect small tumor remnants, follow-up evaluation following the Gamma Knife surgery or, in select cases, following surgical resection. The role of MIB-1 is important in therapeutic decision-making, as tumors with MIB-1 exceeding 2% are characterized by more aggressive clinical course. Single-fraction Gamma Knife surgery remains a valuable therapeutic option for postoperative residual atypical central neurocytomas and central neurocytoma recurrences.

Less common intraparenchymal tumors

The chapter outlines the management of a great variety of rare intraparenchymal tumors. For some like medulloblastomas or ependymomas, GKNS has little to offer. For others like neurocytomas, primary central nervous system lymphomas, and papillary pineal tumors the current findings look most hopeful. For choroid plexus papillomas there is currently not enough information to define the role of GKNS in their treatment. Pineal region tumors are a complex and varied group of neoplasms. Their complexity, variety and ethnic variability means that defining the role of GKNS will require continuing research before a consensus about management can be reached.

Impact of Adjuvant Radiotherapy in Patients with Central Neurocytoma: A Multicentric International Analysis

Simple Summary

Central neurocytoma is a rare tumor accounting for <0.5% of all intracranial tumors. We analyzed 33 patients treated with surgical resection with or without radiotherapy from ten closely cooperating institutions in Germany, Egypt, and Jordan. Patients who received radiotherapy had longer progression-free survival with an acceptable toxicity profile.

Abstract

Background: Central neurocytoma (CN) is a rare tumor accounting for <0.5% of all intracranial tumors. Surgery ± radiotherapy is the mainstay treatment. This international multicentric study aims to evaluate the outcomes of CNs patients after multimodal therapies and identify predictive factors. Patients and methods: We retrospectively identified 33 patients with CN treated between 2005 and 2019. Treatment characteristics and outcomes were assessed. Results: All patients with CN underwent surgical resection. Radiotherapy was delivered in 19 patients. The median radiation dose was 54 Gy (range, 50–60 Gy). The median follow-up time was 56 months. The 5-year OS and 5-year PFS were 90% and 76%, respectively. Patients who received radiotherapy had a significantly longer PFS than patients without RT (p = 0.004) and a trend towards longer OS. In addition, complete response after treatments was associated with longer PFS (p = 0.07). Conclusions: Using RT seems to be associated with longer survival rates with an acceptable toxicity profile.

The last decade's experience of management of central neurocytomas: Treatment strategies and new options

Background:

The purpose of the presented work is to evaluate the last decade’s experience in surgical management of central neurocytoma (CN) and elucidate on the treatment strategies and new options.

Methods:

The current series consists of the remaining 125 patients (70 females and 55 males) operated on during the past decade from 2008 to 2018. Most tumors were resected through transcortical (n = 76, 61%), or transcallosal (n = 40, 32%) approaches. In 5 (4%) patients with predominantly posterior location of the tumor, non-dominant superior parietal lobule approach was utilized. Both approaches (transcortical + transcallosal) were used in 4 (3%) of cases. Seven consecutive patients with large CN underwent prophylactic intraventricular stenting to prevent hydrocephalus.

Results:

Gross total resection was achieved in 45 patients (36%), subtotal resection (STR) in 40 (32%) cases. After surgery, 63 (50%) patients had neurocognitive problems, including disorientation, attention deficit, global amnesia, short-term memory deficits, and perceptual motor and social cognition problems. A total of 26 patients (21%) had postoperative hemorrhage in the resection bed. Obstructive hydrocephalus was noted in 25 (20%) patients. The entrapment of the occipital and/or temporal horns was observed in seven cases. None of the seven patients with prophylactic intraventricular stents required shunting.

Conclusion:

Although high rates of gross total or STR can be expected, the mortality and morbidity remain significant even in the modern neurosurgical era. Prophylactic intraventricular stenting in patients with large posteriorly located tumors with hydrocephalus may prevent ventricular entrapment and shunting. The main risk factors for recurrence are presence of residual disease and Ki-67 index over 5%. Recurrent symptomatic tumors should be treated surgically, whereas asymptomatic progression can be managed with stereotactic radiosurgery. Both treatment modalities are associated with low risk of complications and high tumor control rates.

[Central neurocytomas: long-term treatment outcomes]

Central neurocytoma is a rare benign brain tumor. These tumors may be giant and accompanied by compression of ventricular system and surrounding structures. Modern treatment of brain neurocytoma includes extended resection and restoration of normal CSF circulation. Surgical treatment does not often lead to total resection of these tumors. Redo resection was preferred in patients with tumor progression for a long time. In the last decade, various authors report stereotactic irradiation for continued tumor growth to ensure local growth control. This study was aimed at evaluation of postoperative outcomes in patients with brain neurocytomas, as well as treatment of tumor progression in long-term period.

OBJECTIVE

To analyze recurrence-free survival in patients with brain neurocytomas, risk factors of recurrence-free survival, effectiveness of various treatments for tumor progression and delayed complications.

MATERIAL AND METHODS

Long-term postoperative follow-up data of patients with brain neurocytomas are reported in the manuscript. We analyzed recurrence-free survival and risk factors of recurrence-free survival, treatment outcomes in patients with progression of brain neurocytomas, long-term complications and their prevention.

RESULTS

Follow-up included 84 out of 115 patients with brain neurocytoma after surgical treatment in 2008-2017. Follow-up period ranged from 2 to 10 years (mean 6 years) after resection. Most patients had regression of neurological symptoms after surgery. Continued tumor growth within 12-96 months after surgery occurred in 26 (30.19%) out of 84 patients (19 cases after partial resection and 7 cases after total resection according to MRI data). Two-year recurrence-free survival was 94%, 5-year survival - 83%. Risk factors of continued tumor growth were resection quality and Ki-67 index. Redo resection was performed in 7 cases. Eleven patients underwent stereotactic irradiation for tumor progression. Indications for stereotactic irradiation of central neurocytoma are MR data on continued growth of lateral ventricle tumor without signs of ICH and CSF flow impairment. There were no cases of hemorrhage inside the residual tumor and CSF flow impairment in early postoperative period after redo resection. In all cases (n=11), stereotactic irradiation (mean follow-up 2.5 years) ensured satisfactory control of tumor growth with reduction of the neoplasm in 4 cases and no tumor growth in 7 cases.

CONCLUSION

Resection of central neurocytoma ensures long-term recurrence-free period. The main causes of tumor recurrence are partial resection and high proliferative activity (Ki-67 index over 5%). Redo resection is advisable for tumor progression followed by CSF flow impairment. In case of continued growth of neurocytoma without signs of intracranial hypertension, stereotactic irradiation with various fractionation modes ensures effective and safe control of tumor growth.

Gamma Knife radiosurgery for the treatment of central neurocytoma: a single-institution experience of 25 patients

Central neurocytomas (CNs) are extremely rare tumors that account for 0.1-0.5% of all intracranial neoplasms. Recently, Gamma Knife radiosurgery (GKRS) has become a treatment option in patients with CN. We aimed to evaluate the efficacy and safety of GKRS in 25 CN patients and review the results along with relevant literature. GKRS patient database was searched, and 25 patients who underwent GKRS for CN between 2009 and 2018, were evaluated retrospectively. The study cohort included 15 female and ten male patients with a median age of 32 years (range, 5-60). The most common presenting symptom was headache (88%). The neurological examination was unremarkable in all patients, except for one patient with decreased vision. Twenty patients (80%) had a history of surgical resection. Most of the tumors (92%) were located in the ventricles, and the median tumor volume was 4.8 cm³ (range, 0.8-28.1). The median marginal dose was 14 Gy (range, 12-15) to a median isodose of 50% (range, 40-50). Following a median follow-up of 80 months (range, 36-138), local tumor control was achieved in 100% of patients. Distant recurrence was observed in one patient (4%). No adverse radiation effect was observed. Regarding non-specific post-GKRS symptoms, one patient experienced a prolonged headache, and one epileptic patient experienced a brief partial seizure. In our patient cohort, GKRS yielded favorable local tumor control (100%) during a median follow-up of 6.6 years. Our series demonstrates that GKRS is an effective and safe treatment option for patients with primary or residual CNs.

[Choice optimisation of radiation therapy technique for central neurocytomas from literature data]

Neurocytomas represent 0,25 to 0,5 of brain tumours. These tumours have neuronal differentiation. It's a young adult disease. The main treatment is neurosurgery. The place of other therapies is still unclear, noticeably with regards to radiotherapy. This review aim is to determine the place and the modalities of radiotherapy in the management of neurocytomas. A literature search using PubMed allowed to select the most relevant studies. Finally, 22 studies were selected according to pre-established criteria to answer the problem. All studies were retrospective studies except one. The analysis conclusion defined radiotherapy as a treatment of choice in selected patients, when surgical resection was incomplete or when tumour was atypical.

[Central neurocytomas: surgical treatment outcomes and new trends and approaches in the treatment]

AIM

Central neurocytomas of the brain are rare benign tumors of the cerebral lateral ventricles. The main treatment for them is surgical resection. Resection provides a long-term relapse-free period, but surgical intervention is associated with a number of significant difficulties due to the location, size, and blood supply features of these tumors. The postoperative period is often accompanied by hemorrhagic complications, impaired cerebrospinal fluid circulation, and worsening of neurological symptoms.

PURPOSE

The study purpose was to evaluate the effectiveness of surgical treatment in neurocytoma patients, assess the risk of complications after neurocytoma resection, and develop techniques for their prevention.

MATERIAL AND METHODS

The paper presents surgical treatment outcomes in 115 patients with central neurocytomas for the period from 2008 to 2017. The choice of a surgical approach and the surgical features are described in detail, and the radicality is assessed with allowance for the location and size of tumors. The immediate clinical outcomes of treatment are evaluated, complications are analyzed, and methods for prevention and treatment of complications are described.

RESULTS

Analysis of the data revealed that the tumor was resected totally in 41 (36%) patients, subtotally - in 37 (32%), and partially in 37 (32%). The most common and dangerous complications were as follows: CSF circulation occlusion with the development of hydrocephalus in 23 (20%) patients; hemorrhage into the residual tumor, which required immediate revision of the surgical wound in most cases, in 25 (22%) patients. In the early postoperative period after tumor resection, almost all patients developed deterioration of condition with transient worsening of cerebral and focal symptoms. The degree and duration of this worsening were different. In 50% of cases, the postoperative condition was characterized by reduced voluntary activity, drowsiness or jitteriness, and motor or speech anxiety.

CONCLUSION

We consider resection of neurocytomas as the main treatment option, despite the potential complications and effects of the operation.

The role of proton beam therapy in central neurocytoma: A single-institution experience

PURPOSE

Central neurocytomas (CNs) are rare World Health Organization grade II tumors managed with surgery and radiation therapy. We report our experience in managing CN with proton beam therapy (PBT) when radiation therapy was used.

METHODS AND MATERIALS

We identified 61 patients with pathologically diagnosed CN treated at our institution between 1996 and 2016, of which 24 met inclusion criteria. Patient, tumor, and treatment characteristics are reported in context of progression-free survival and treatment-related adverse events.

RESULTS

Of 24 patients identified, median age at diagnosis was 21 years (range, 14-60). Median maximal tumor diameter was 4.5 cm (range, 1.4-6.8). Eighteen (75%) patients underwent upfront surgery alone. Sixteen (67%) patients received adjuvant or salvage PBT at a median dose of 54 Gy (relative biological effectiveness). Median follow-up was 56 months. Median progression-free survival (PFS) was 61 months. Eleven patients had disease progression with median time to progression of 22 months. Of the 5 patients with gross total resection, 4 experienced local recurrence and had MIB-1 >4% (range, 4.5-30). There was improved PFS with addition of PBT to definitive surgery (log-rank, P = .06); there was no disease progression to date. In patients who experienced disease recurrence/progression, MIB-1 <4% was associated with improved PFS (log-rank, P = .007). All patients tolerated PBT well with toxicities typical for cranial irradiation and with no grade 3+ toxicities.

CONCLUSION

In our cohort, CN with elevated MIB-1 index were at increased risk for disease progression. However, adjuvant radiation therapy appears to effectively prevent failure. PBT toxicities appear to be comparable to if not less than published photon experiences.

Clinical characteristics and prognostic factors of brain central neurocytoma

BACKGROUND & AIMS

This study is designed for the clinical characteristics and prognostic factors of central neurocytoma (CN).

METHODS

CN patients from 2004 to 2012 were enrolled from the Surveillance Epidemiology and End Results (SEER) data. Clinical characteristics including age, sex, race, tumor size, tumor number, surgery, and radiation therapy were summarized. Univariate and multivariate analysis were performed to explore the prognostic factors of CN.

RESULTS

CN tended to be borderline malignant and single lesion. Compared with other brain tumor (NCN), Patients with CN (CNs) were more likely to be female, young, and non-white race. Surgery was the primary treatment of CN. Univariate and Multivariate analysis indicated tumor number and surgery were both independent prognostic factors of CN (P < 0.05). Unifocal CNs had a lower mortality risk than multifocal ones (HR 0.167, 95% CI 0.052-0.537), surgery significantly reduced the death risk of CNs (HR 0.284, 95% CI 0.088-0.921).

CONCLUSIONS

CN tend to be borderline malignant, single lesion, operated on. Most CNs are female and younger. single lesion and surgery are the independent positive prognostic factors of CN.

Systematic Analysis of Clinical Outcomes Following Stereotactic Radiosurgery for Central Neurocytoma

Central neurocytoma (CN) typically presents as an intraventricular mass causing obstructive hydrocephalus. The first line of treatment is surgical resection with adjuvant conventional radiotherapy. Stereotactic radiosurgery (SRS) was proposed as an alternative therapy for CN because of its lower risk profile. The objective of this systematic analysis is to assess the efficacy of SRS for CN. A systematic analysis for CN treated with SRS was conducted in PubMed. Baseline patient characteristics and outcomes data were extracted. Heterogeneity and publication bias were also assessed. Univariate and multivariate linear regressions were used to test for correlations to the primary outcome: local control (LC). The estimated cumulative rate of LC was 92.2% (95% confidence interval: 86.5-95.7%, p<0.001). Mean follow-up time was 62.4 months (range 3-149 months). Heterogeneity and publication bias were insignificant. The univariate linear regression models for both mean tumor volume and mean dose were significantly correlated with improved LC (p<0.001). Our data suggests that SRS may be an effective and safe therapy for CN. However, the rarity of CN still limits the efficacy of a quantitative analysis. Future multi-institutional, randomized trials of CN patients should be considered to further elucidate this therapy.