Local radiotherapeutic management of ependymomas with fractionated stereotactic radiotherapy (FSRT)

Polish Multi-Institutional Study of Children with Ependymoma-Clinical Practice Outcomes in the Light of Prospective Trials

We performed a multi-institutional analysis of 74 children with ependymoma to evaluate to what extent the clinical outcome of prospective trials could be reproduced in routine practice. The evaluation of factors that correlated with outcome was performed with a log rank test and a Cox proportional-hazard model. Survival was estimated with the Kaplan–Meier method. The majority of patients had brain tumours (89%). All had surgery as primary treatment, with adjuvant radiotherapy (RTH) and chemotherapy (CTH) applied in 78% and 57%, respectively. Median follow-up was 80 months and 18 patients died. Five- and 10-year overall survival (OS) was 83% and 73%. Progression was observed in 32 patients, with local recurrence in 28 cases. The presence of metastases was a negative prognostic factor for OS. Five- and 10-year progression-free survival (PFS) was 55% and 40%, respectively. The best outcome in patients with non-disseminated brain tumours was observed when surgery was followed by RTH (+/−CTH afterwards; p = 0.0001). Children under 3 years old who received RTH in primary therapy had better PFS (p = 0.010). The best outcome of children with ependymoma is observed in patients who received radical surgery followed by RTH, and irradiation should not be omitted in younger patients. The role of CTH remains debatable.

Intraventricular neuroepithelial tumors: surgical outcome, technical considerations and review of literature

Background

Intraventricular neuroepithelial tumors (IVT) are rare lesions and comprise different pathological entities such as ependymomas, subependymomas and central neurocytomas. The treatment of choice is neurosurgical resection, which can be challenging due to their intraventricular location. Different surgical approaches to the ventricles are described. Here we report a large series of IVTs, its postoperative outcome at a single tertiary center and discuss suitable surgical approaches.

Methods

We performed a retrospective chart review at a single tertiary neurosurgical center between 03/2009–05/2019. We included patients that underwent resection of an IVT emphasizing on surgical approach, extent of resection, clinical outcome and postoperative complications.

Results

Forty five IVTs were resected from 03/2009 to 05/2019, 13 ependymomas, 21 subependymomas, 10 central neurocytomas and one glioependymal cyst. Median age was 52,5 years with 55.6% (25) male and 44.4% (20) female patients. Gross total resection was achieved in 93.3% (42/45). 84.6% (11/13) of ependymomas, 100% (12/21) of subependymomas, 90% (9/10) of central neurocytomas and one glioependymal cyst were completely removed. Postoperative rate of new neurological deficits was 26.6% (12/45). Postoperative new permanent cranial nerve deficits occurred in one case with 4th ventricle subependymoma and one in 4th ventricle ependymoma. Postoperative KPSS was 90% (IR 80–100). 31.1% of the patients improved in KPSS, 48.9% remained unchanged and 20% declined. Postoperative adverse events rate was 20.0%. Surgery-related mortality was 2.2%. The rate of shunt/cisternostomy-dependent hydrocephalus was 13.3% (6/45). 15.4% of resected ependymomas underwent adjuvant radiotherapy. Mean follow-up was 26,9 (±30.1) months.

Conclusion

Our surgical findings emphasize satisfactory complete resection throughout all entities. Surgical treatment can remain feasible, if institutional experience is given. Satisfying long-term survival and cure is possible by complete removal. Gross total resection should always be performed under function-remaining aspects due to mostly benign or slow growing nature of IVTs. Further data is needed to evaluate standard of care and alternative therapy options in rare cases of tumor recurrence or in case of patient collective not suitable for operative resection.

Craniospinal irradiation as part of re-irradiation for children with recurrent intracranial ependymoma

BACKGROUND

The goal of this study was to evaluate outcomes in children with relapsed, molecularly characterized intracranial ependymoma treated with or without craniospinal irradiation (CSI) as part of a course of repeat radiation therapy (re-RT).

METHODS

This was a retrospective cohort study of 31 children. Patients with distant relapse received CSI as part of re-RT. For patients with locally recurrent ependymoma, those treated before 2012 were re-irradiated with focal re-RT. In 2012, institutional practice changed to offer CSI, followed by boost re-RT to the site of resected or gross disease.

RESULTS

Median follow-up was 5.5 years. Of 9 patients with distant relapse after initial RT, 2-year freedom from progression (FFP) and overall survival (OS) were 12.5% and 62.5%, respectively. There were 22 patients with local failure after initial RT. In these patients, use of CSI during re-RT was associated with improvement in 5-year FFP (83.3% with CSI vs 15.2% with focal re-RT only, P = 0.030). In the subgroup of patients with infratentorial primary disease, CSI during re-RT also improved 5-year FFP (100% with CSI, 10.0% with focal re-RT only, P = 0.036). Twenty-three patients had known molecular status; all had posterior fossa group A tumors (n = 17) or tumors with a RELA (v-rel avian reticuloendotheliosis viral oncogene homolog A) fusion (n = 6). No patient developed radiation necrosis after fractionated re-RT, though almost all survivors required assistance throughout formal schooling. Five out of 10 long-term survivors have not developed neuroendocrine deficits.

CONCLUSIONS

Re-irradiation with CSI is a safe and effective treatment for children with locally recurrent ependymoma and improves disease control compared with focal re-irradiation, with the benefit most apparent for those with infratentorial primary tumors.

Proton and carbon ion radiotherapy for primary brain tumors and tumors of the skull base

To analyze clinical concepts, toxicity and treatment outcome in patients with brain and skull base tumors treated with photons and particle therapy.

MATERIAL AND METHODS

In total 260 patients with brain tumors and tumors of the skull base were treated at the Heidelberg Ion Therapy Center (HIT). Patients enrolled in and randomized within prospective clinical trials as well as bony or soft tissue tumors are not included in this analysis. Treatment was delivered as protons, carbon ions, or combinations of photons and a carbon ion boost. All patients are included in a tight follow-up program. The median follow-up time is 12 months (range 2-39 months).

RESULTS

Main histologies included meningioma (n = 107) for skull base lesions, pituitary adenomas (n = 14), low-grade gliomas (n = 51) as well as high-grade gliomas (n = 55) for brain tumors. In all patients treatment could be completed without any unexpected severe toxicities. No side effects > CTC Grade III were observed. To date, no severe late toxicities were observed, however, for endpoints such as secondary malignancies or neurocognitive side effects follow-up time still remains too short. Local recurrences were mainly seen in the group of high-grade gliomas or atypical meningiomas; for benign skull base meningiomas, to date, no recurrences were observed during follow-up.

CONCLUSION

The specific benefit of particle therapy will potentially reduce the risk of secondary malignancies as well as improve neurocognitive outcome and quality of life (QOL); thus, longer follow-up will be necessary to confirm these endpoints. Indication-specific trials on meningiomas and gliomas are underway to elucidate the role of protons and carbon ions in these indications.

Current treatment options for pediatric and adult patients with ependymoma

OPINION STATEMENT

Survival rates for patients with ependymoma, a glial tumor arising from the ependymal cells lining the ventricles of the brain and spinal cord canal, have changed little during the past decade. Contemporary "standard" therapy for children and adults with ependymoma consists of maximal surgical resection followed by focal irradiation except in cases of disseminated disease. Despite refinements in radiotherapy techniques and improvements in survival for patients with gross totally resected, nonanaplastic disease, many therapeutic challenges remain, especially for patients with unresectable, macroscopic, metastatic, or anaplastic disease. Moreover, radiotherapy to the developing central nervous system, especially in patients younger than age 5 years, can have potential long-term neurocognitive and neuroendocrine sequelae. Chemotherapy has not played a role in most treatment regimens for ependymoma to date, but due to the ongoing therapeutic challenges for a subset of patients, this modality is being reinvestigated in a few ongoing studies. Early recognition of patients who will not respond to primary therapy is imperative to modify treatment regimens, such as intensification with the addition of adjuvant chemotherapy, the use of novel experimental therapies, or their combination. Refinements in patient stratification schemes that are based on a combination of clinical variables and molecular profiles also require improved knowledge of tumor biology. Several molecular alterations have been identified already, some of which may be of prognostic significance. Furthermore, disruption of molecular alterations in signaling pathways involved in the development and maintenance of ependymoma by using novel molecularly targeted therapies may improve outcomes and reduce toxicity for patients with ependymoma.

Prognostic factors and treatment options for paediatric ependymomas

The aim of this study was to determine factors of prognostic relevance for paediatric ependymomas, and evaluate the efficacy of treatment modalities. This is a retrospective study of 43 patients with ependymoma (<18 years) who underwent a combination of surgical excision, chemotherapy, and/or radiotherapy treatment at The Prince of Wales Cancer Centre between 1969 and 2009. Statistical analysis was performed to assess the prognostic relevance of various parameters affecting the two-year and five-year overall survival (OS) and progression-free survival (PFS). The five-year OS and PFS were 50.3% and 44.8% respectively (median follow-up 50 months). Eighteen patients (41.9%) experienced tumour recurrence: 13 had a local recurrence (LR) and five had both LR and distant recurrence. On univariate analysis, a more favourable prognosis in terms of both OS and PFS was evident for supratentorial tumours compared to infratentorial tumours (OS p=0.007, PFS p=0.045), stereotactic radiosurgery/ fractionated stereotactic radiotherapy compared to craniospinal irradiation or local posterior fossa/local brain±boost radiotherapy modalities (OS p=0.047, PFS p=0.031), total radiotherapy dose >50 Gy compared to ≤50 Gy (OS p=0.008, PFS p=0.005), and in patients with no tumour recurrence compared to those with recurrence (OS p=0.03, PFS p<0.001). Although not statistically significant, a more favourable multivariate outcome was evident in patients who underwent complete surgical resection. Chemotherapy treatment and histopathological grade, however, were not relevant to prognosis. This study supports the need to pursue more aggressive treatment for infratentorial and/or recurrent tumours. Ideal treatment involves maximal surgical resection, followed by adjuvant radiotherapy (>50 Gy).

[Stereotactic radiotherapy in pediatric indications]

Stereotactic radiotherapy is a very high precision procedure, which has been limited to radiosurgery for a long time. Technological improvements allowed the development of radiotherapy in stereotactic conditions, leading to a lot of innovations. Previously indicated for cerebral pathologies, this procedure is now developed for extracerebral locations. In paediatrics, stereotactic radiotherapy is still limited, delivered precociously, due to the possibility of long-term late effects that needs to be addressed. This review reports the different useful conditions, technical evolutions, and the current validated paediatric indications, with differences from adults, and future directions.

Carbon ion radiotherapy performed as re-irradiation using active beam delivery in patients with tumors of the brain, skull base and sacral region

INTRODUCTION

To asses carbon ion radiation therapy (RT) performed as re-irradiation in 28 patients with recurrent tumors.

MATERIALS AND METHODS

Twenty-eight patients were treated with carbon ion RT as re-irradiation for recurrent chordoma and chondrosarcoma of the skull base (n=16 and n=2), one chordoma and one chondrosarcoma of the os sacrum, high-risk meningioma (n=3), adenoid-cystic carcinoma (n=4) as well as one SCCHN. All patients were treated using active raster scanning, and treatment planning was performed on CT- and MRI-basis. All patients were followed prospectively during follow-up.

RESULTS

In all patients re-irradiation could be applied safely without interruptions. For skull base tumors, local tumor control after re-irradiation was 92% at 24 months and 64% at 36 months. Survival after re-irradiation was 86% at 24 months, and 43% at 60 months. In all three meningiomas treated with C12 for re-irradiation, the tumor recurrence was located within the former RT-field. Two patients developed tumor progression at 6 months, and in one patient the tumor remained stable for 67 months. In patients with head-and-neck tumors, three patients developed local tumor progression at 12, 24 and 29 months after re-irradiation. Median local progression-free survival was 24 months. For sacral tumors, re-irradiation offered palliation with tumor control for 24 and 36 months.

CONCLUSION

Due to the physical characteristics particle therapy offers a new treatment modality in cases with tumor recurrences. With carbon ions, the additional biological benefits may be exploited for long-term tumor control. Further evaluation in a larger patients' cohort will be performed in the future.

Treatment and outcome of children with relapsed ependymoma: a multi-institutional retrospective analysis

INTRODUCTION

More than a third of children with ependymoma experience relapse, and despite multimodal treatment, less than 25% of them can then achieve long-term survival. Prognostic factors for patients who relapse have not been extensively analyzed.

PATIENTS AND METHODS

We retrospectively analyzed 82 patients from four pediatric oncology European institutions in order to identify prognostic factors and influence of treatment modalities in relapsed ependymoma.

RESULTS

First relapse occurred after a median of 19 months (1 month-16 years). Five-year progression-free survival and overall survival of the cohort were 17% and 27.6%, respectively. Survival was statistically significantly higher for patients achieving gross total resection. No survival benefit was seen for children receiving chemotherapy whereas patients who were amenable to some form of re-irradiation had a better outcome. Objective responses were found in more than 25% of patients receiving oral etoposide, temozolomide, or vincristine/etoposide/cyclophosphamide regimens. Multivariate analysis confirmed that patients with mixed relapses, no surgery at relapse, and receiving chemotherapy did worse (hazard ratio = 3.6, 3.3, and 1.7, respectively, all p < 0.05).

DISCUSSION

Relapsed ependymoma carries a very poor prognosis with an indolent chronic course, leading to death in approximately 90% of the patients. Complete surgical resection whenever possible should be encouraged. Radiation therapy of the relapsed lesions can provide some minor benefit whereas chemotherapy despite the occasional responses provides no benefit in the final outcome which is dismal. Efforts have to be orchestrated internationally to enroll these patients on clinical trials using biology-based therapies.

Primary Myxopapillary Ependymoma of the Medulla

OBJECTIVE

Myxopapillary ependymoma is a subclassification of ependymoma that is thought to be nearly exclusive to the conus medullaris or filum terminale. Primary intracerebral or brainstem myxopapillary ependymomas are rare.

CLINICAL PRESENTATION

An 8-year-old child presented with a 5-month history of nausea and vomiting and a 1-week history of headache. Magnetic resonance imaging revealed a nodular mass in the medulla with an associated cyst extending into the fourth ventricle.

INTERVENTION

A suboccipital craniotomy was performed, and a gross total resection of the lesion and cyst was achieved. Histological examination confirmed the diagnosis of myxopapillary ependymoma. A discussion of other reported cases of extraspinal myxopapillary ependymomas is presented.

CONCLUSION

This is the first report of a case of myxopapillary ependymoma, confirmed by histology, in the medulla. Although rare, myxopapillary ependymomas outside of the filum terminale do exist.

Ependymoma: an update

The authors provide an update on most issues related to biology, diagnosis, and treatment of children with ependymoma based on a literature review. Ependymoma is the third most common brain tumor in children and overall survival ranges from 24% to 75% at 5 years. The extent of surgical resection remains the principal risk factor that clearly influences outcome. The influence of age, location, grade, or stage has proved to be more controversial. Current standard therapy includes surgical resection and radiotherapy. Chemotherapy has a role in infants to avoid/delay radiotherapy and can be helpful to improve resectability. About half of patients will experience relapse, and outcome is dismal. New radiation modalities, reirradiation, chemotherapy, or targeted agents have been tested with promising results. Results of multi-institutional clinical trials are awaited to determine the best first-line treatment, while results of early phase I/ II trials will explore directed therapies based on new biologic factors.

Three-dimensional conformal radiation therapy for ependymoma

INTRODUCTION

The application of conformal radiation therapy in the treatment of pediatric ependymoma is a success story resulting from advances in radiation therapy planning and delivery. These advances occurred at a time when clinical trial results confirmed that radiotherapy avoidance strategies were unsuccessful.

DISCUSSION

Investigators have been keen to confirm the promise of newer radiation therapy methods even for the youngest children. When preliminary results suggested that high-dose focal irradiation could be safely administered through systematic targeting and that cognitive function could be preserved, investigators moved to include conformal therapy in the frontline management of children regardless of age. The results with postoperative conformal radiation therapy were further enhanced when neurosurgeons increased the rate of gross-total resection and recognized that second surgery could be safely accomplished after incomplete initial resection. With more than a decade of experience, the role of conformal radiation therapy in the treatment of childhood ependymoma has been firmly established as investigators consider new trials to increase disease control and improve functional outcomes.

[Stereotactical radiotherapy in pediatrics indications]

Stereotactical radiotherapy is a very high precision procedure, limited to radiosurgery since a long time. Technologic progress permitted to develop radiotherapy in stereotactical conditions, leading to a lot of innovations. Previously indicated for cerebral pathologies, this procedure is now developed for extracerebral locations. In pediatrics, stereotactical radiotherapy is still limited, delivered precociously, due to the possibility of long-term late effects that needs to be to addressed. This review reports the different useful conditions, technical evolutions, and the current validated pediatric indications, with differences from adults, and future directions. Current state of pediatric stereotactical radiotherapy used in France is presented.

Maximally safe resection followed by hypofractionated re-irradiation for locally recurrent ependymoma in children

BACKGROUND

Treatment failure in children with ependymoma is relatively common, with the majority of events consisting of local failure. Salvage therapy for these children historically had poor results, with repeated local recurrences. To improve these outcomes, we began to offer hypofractionated re-irradiation after resection at first local recurrence. To minimize the duration of therapy, we chose a hypofractionated regimen that has been shown to be well tolerated in adult patients.

PROCEDURE

We performed a review of the experience at the Children's Hospital in Denver and at the Department of Radiation Oncology at the University of Colorado Denver from 1995 to 2008 with hypofractionated re-irradiation after maximally safe resection in children with locally recurrent ependymoma.

RESULTS

Six children with locally recurrent ependymoma were seen in that time period. After maximally safe resection, all six received hypofractionated radiation therapy of 24-30 Gy delivered in three fractions. With a median follow-up of 28 months from the time of re-irradiation, all six children are alive with no evidence of disease. Three children had evidence of radiation necrosis, either clinically or based on imaging, but none required significant intervention.

CONCLUSIONS

Hypofractionated re-irradiation after resection for locally recurrent ependymoma is well tolerated. This approach also appears to provide good local control. Additional follow-up is required to determine the efficacy and potential late effects of hypofractionated re-irradiation in this patient population.

Ependymomas of the adult: molecular biology and treatment

PURPOSE OF REVIEW

To review state of art and relevant advances in the molecular biology and management of ependymomas of the adult.

RECENT FINDINGS

Ependymomas of the adult are uncommon neoplasms of the central nervous system, and may occur either in the brain or the spinal cord. Compared with intracranial ependymomas, spinal ependymomas are less frequent and exhibit a better prognosis. Studies performed on genetic changes in ependymoma provide some insight into the pathogenesis and prognostic markers and yield new therapeutic targets, particularly focused on signal transduction modulators. The majority of studies have shown a major impact of extent of resection; thus, a complete resection must be performed, whenever possible, at first surgery or at reoperation. Involved field radiotherapy is recommended for anaplastic or incompletely resected grade II tumors. Craniospinal irradiation is reserved for metastatic disease. Chemotherapy is not advocated as primary treatment, and is best utilized as salvage treatment for patients failing surgery and radiotherapy.

SUMMARY

Owing to the rarity of the disease, the literature regarding ependymomas in adults is scarce and limited to retrospective series. Thus, the level of evidence regarding therapeutic strategies is low and universally accepted guidelines are lacking. Molecular biology studies suggest some potential new therapeutic targets.

A retrospective study of surgery and reirradiation for recurrent ependymoma

PURPOSE

To report disease control for patients with recurrent ependymoma (EP) treated with surgery and a second course of radiation therapy (RT(2)).

PATIENTS AND METHODS

Thirty-eight pediatric patients (median age, 2.7 years) with initially localized EP at the time of definitive RT underwent a second course of RT after local (n = 21), metastatic (n = 13), or combined (n = 4) failure. Reirradiation included radiosurgery (n = 6), focal fractionated reirradiation (n = 13), or craniospinal irradiation (CSI; n = 19).

RESULTS

Initial time to failure was 16 months, and median age at second treatment was 4.8 years. Radiosurgery resulted in significant brainstem toxicity and one death (median dose, 18 Gy). Progression-free survival ratio was greater than unity for 4 of 6 patients; there was one long-term survivor. Three of 13 patients treated using focal fractionated reirradiation (median combined dose, 111.6 Gy) experienced metastasis. The CSI was administered to 12 patients with metastatic failure, 3 patients with local failure, and 4 patients with combined failure. The 4-year event-free survival rate was 53% +/- 20% for 12 patients with metastatic failure treated with CSI. Failure after CSI was observed in 1 of 3 patients with a history of local failure and 3 of 4 patients with a history of combined failure.

CONCLUSION

Patients with locally recurrent EP experience durable local tumor control, but remain at risk of metastasis. Patients with metastatic EP failure may receive salvage therapy that includes a component of CSI. Durability of disease control and long-term effects from this approach require further follow-up.

Role of stereotactic radiosurgery and fractionated stereotactic radiotherapy in pediatric brain tumors

Brain tumors are the most common solid tumor in childhood. Surgery and/or fractionated radiotherapy are conventional treatment modalities. Stereotactic radiosurgery (SRS) and fractionated stereotactic radiotherapy (FSRT) are advanced radiation therapy techniques that have been frequently used in adults with brain tumors but they are less frequently used in pediatric patients. SRS and FSRT can potentially add to the armamentarium against brain tumors in children. This article will review the role of SRS and FSRT in the management of pediatric brain tumors.

CHAINED LIGHTNING

RADIOSURGERY IS FUNDAMENTALLY the harnessing of energy and delivering it to a focal target for a therapeutic effect. The evolution of radiosurgical technology and practice has served toward refining methodologies for better conformal energy delivery. In the past, this has resulted in developing strategies for improved beam generation and delivery. Ultimately, however, our current instrumentation and treatment modalities may be approaching a practical limit with regard to further optimizing energy containment.

In looking forward, several strategies are emerging to circumvent these limitations and improve conformal radiosurgery. Refinement of imaging techniques through functional imaging and nanoprobes for cancer detection may benefit lesion localization and targeting. Methods for enhancing the biological effect while reducing radiation-induced changes are being examined through dose fractionation schedules. Radiosensitizers and photosensitizers are being investigated as agents for modulating the biological response of tissues to radiation and alternative energy forms. Discovery of new energy modalities is being pursued through development of microplanar beams, free electron lasers, and high-intensity focused ultrasound. The exploration of these future possibilities will provide the tools for radiosurgical treatment of a broader spectrum of diseases for the next generation.