Radiosurgery outcomes in infratentorial juvenile pilocytic astrocytomas.

PURPOSE: To assess survival and neurological outcomes for patients who underwent primary or salvage stereotactic radiosurgery (SRS) for infratentorial juvenile pilocytic astrocytomas (JPA). METHODS: Between 1987 and 2022, 44 patients underwent SRS for infratentorial JPA. Twelve patients underwent primary SRS and 32 patients underwent salvage SRS. The median patient age at SRS was 11.6 years (range, 2-84 years). Prior to SRS, 32 patients had symptomatic neurological deficits, with ataxia as the most common symptom in 16 patients. The median tumor volume was 3.22 cc (range, 0.16-26.6 cc) and the median margin dose was 14 Gy (range, 9.6-20 Gy). RESULTS: The median follow-up was 10.9 years (range, 0.42-26.58 years). Overall survival (OS) after SRS was 97.7% at 1-year, and 92.5% at 5- and 10-years. Progression free survival (PFS) after SRS was 95.4% at 1-year, 79.0% at 5-years, and 61.4% at 10-years. There is not a significant difference in PFS between primary and salvage SRS patients (p = 0.79). Younger age correlated with improved PFS (HR 0.28, 95% CI 0.063-1.29, p = 0.021). Sixteen patients (50%) had symptomatic improvements while 4 patients (15.6%) had delayed onset of new symptoms related to tumor progression (n = 2) or treatment related complications (n = 2). Tumor volumetric regression or disappearance after radiosurgery was found in 24 patients (54.4%). Twelve patients (27.3%) had delayed tumor progression after SRS. Additional management of tumor progression included repeat surgery, repeat SRS, and chemotherapy. CONCLUSIONS: SRS was a valuable alternative to initial or repeat resection for deep seated infratentorial JPA patients. We found no survival differences between patients who had primary and salvage SRS.

Adult Intramedullary Pilocytic Astrocytomas: Clinical Features, Management, and Outcomes.

Purpose: Adult intramedullary pilocytic astrocytomas (PAs) are exceedingly rare. The aim of this study was to summarize our experiences in treating adult intramedullary PAs. Materials and Methods: We retrospectively reviewed the records of seven adult patients who underwent microsurgery for intramedullary PAs between 2010 and 2017. Magnetic resonance imaging was the standard radiological investigation. The diagnosis of PAs was based on pathology. All the follow-up data were obtained during office visits. Results: There were three males and four females with the mean age of 40.9 years. The tumors generally exhibited hypointensity on T1-weighted images (WI) and hyperintensity on T2WI. Contrast-enhanced T1WI showed heterogeneous enhancement. Gross total resection (GTR) of the tumor was achieved in four cases and subtotal resection (STR) was achieved in three cases. Two cases of STR received postoperative radiotherapy. One STR case had mildly residual tumor regrowth. At the last follow-up, neurological status was improved in six patients. Conclusion: The accurate diagnosis of adult intramedullary PAs depends on pathology. GTR is the best treatment and the outcome is favorable. STR increases the risk of tumor recurrence, and regular follow-up is necessary. Due to uncertain therapeutic efficacy, radiotherapy should be considered carefully for cases of STR.

Radiotherapy delays malignant transformation and prolongs survival in patients with IDH-mutant gliomas.

OBJECTIVE: IDH-mutant lower-grade gliomas (LGGs, grade 2 or 3) eventually transform into secondary grade 4 astrocytomas (sAIDHmut/G4). Here, we sought to describe the transformation time, risk factors, and outcomes in malignant transformation of IDH-mutant LGGs. METHODS: We screened data for 108 patients with sAIDHmut/G4 in the Chinese Glioma Genome Atlas who had initial IDH-mutant LGGs and underwent reoperation during 2005-2021. We evaluated the transformation time from IDH-mutant LGGs to sAIDHmut/G4, and associated risk factors and outcomes. Malignant transformation was defined as pathological confirmation of grade 4 astrocytoma. RESULTS: The median age of the 108 patients with IDH-mutant LGGs was 35 years (range, 19-54); the median age at transformation was 40 years (range, 25-62); and the median follow-up time for all patients was 146 months (range, 121-171). The average transformation time was 58.8 months for all patients with LGGs (range, 5.9-208.1); 63.5 and 51.9 months for grade 2 and 3 gliomas, respectively; and 58.4 and 78.1 months for IDH-mutant/1p/19q-non-codeleted astrocytomas and IDH-mutant/1p/19q-codeleted oligodendrogliomas, respectively. Univariate and multivariate analysis indicated that radiotherapy [hazard ratio (HR), 0.29; 95% confidence interval (CI), 0.137-0.595; P = 0.001] and non-A blood type (HR, 0.37; 95% CI, 0.203-0.680; P = 0.001) were protective factors against delayed malignant transformation. Radiotherapy was associated with improved survival after transformation (HR, 0.44; 95% CI, 0.241-0.803; P = 0.008), overall survival (HR, 0.50; 95% CI, 0.265-0.972; P = 0.041), and progression-free survival (HR, 0.25; 95% CI, 0.133-0.479; P < 0.0001) in patients with IDH-mutant gliomas. CONCLUSIONS: Radiotherapy is associated with delayed malignant transformation and improved survival in patients with IDH-mutant gliomas.

Oncolytic DNX-2401 Virus for Pediatric Diffuse Intrinsic Pontine Glioma.

BACKGROUND: Pediatric patients with diffuse intrinsic pontine glioma (DIPG) have a poor prognosis, with a median survival of less than 1 year. Oncolytic viral therapy has been evaluated in patients with pediatric gliomas elsewhere in the brain, but data regarding oncolytic viral therapy in patients with DIPG are lacking. METHODS: We conducted a single-center, dose-escalation study of DNX-2401, an oncolytic adenovirus that selectively replicates in tumor cells, in patients with newly diagnosed DIPG. The patients received a single virus infusion through a catheter placed in the cerebellar peduncle, followed by radiotherapy. The primary objective was to assess the safety and adverse-event profile of DNX-2401. The secondary objectives were to evaluate the effect of DNX-2401 on overall survival and quality of life, to determine the percentage of patients who have an objective response, and to collect tumor-biopsy and peripheral-blood samples for correlative studies of the molecular features of DIPG and antitumor immune responses. RESULTS: A total of 12 patients, 3 to 18 years of age, with newly diagnosed DIPG received 1×1010 (the first 4 patients) or 5×1010 (the subsequent 8 patients) viral particles of DNX-2401, and 11 received subsequent radiotherapy. Adverse events among the patients included headache, nausea, vomiting, and fatigue. Hemiparesis and tetraparesis developed in 1 patient each. Over a median follow-up of 17.8 months (range, 5.9 to 33.5), a reduction in tumor size, as assessed on magnetic resonance imaging, was reported in 9 patients, a partial response in 3 patients, and stable disease in 8 patients. The median survival was 17.8 months. Two patients were alive at the time of preparation of the current report, 1 of whom was free of tumor progression at 38 months. Examination of a tumor sample obtained during autopsy from 1 patient and peripheral-blood studies revealed alteration of the tumor microenvironment and T-cell repertoire. CONCLUSIONS: Intratumoral infusion of oncolytic virus DNX-2401 followed by radiotherapy in pediatric patients with DIPG resulted in changes in T-cell activity and a reduction in or stabilization of tumor size in some patients but was associated with adverse events. (Funded by the European Research Council under the European Union's Horizon 2020 Research and Innovation Program and others; EudraCT number, 2016-001577-33; ClinicalTrials.gov number, NCT03178032.).

Trends in radiation dose for low grade gliomas across the United States.

PURPOSE: Adjuvant radiation is often used in patients with low grade gliomas with high-risk characteristics with a recommended dose of 45-54 Gy. We used the National Cancer Database (NCDB) to see which doses were being used, and if any difference was seen in outcome. METHODS: We queried the NCDB for patients with WHO Grade 2 primary brain tumors treated with surgery and adjuvant radiotherapy. We divided the cohort into dose groups: 45-50 Gy, 50.4-54 Gy, and > 54 Gy. Multivariable logistic regression was used to identify predictors of low and high dose radiation. Propensity matching was used to account for indication bias. RESULTS: We identified 1437 patients meeting inclusion criteria. Median age was 45 years and 62% of patients were > 40 years old. Nearly half of patients (48%) had astrocytoma subtype and 70% had subtotal resection. The majority of patients (69%) were treated to doses between 50.4 and 54 Gy. Predictors of high dose radiation (> 54 Gy) were increased income, astrocytoma subtype, chemotherapy receipt, and treatment in later year (2014). The main predictors of survival were age > 40, astrocytoma subtype, and insurance type. Patients treated to a dose of > 54 Gy had a median survival of 73.5 months and was not reached in those treated to a lower dose (p = 0.0041). CONCLUSIONS: This analysis shows that 50.4-54 Gy is the most widely used radiation regimen for the adjuvant treatment of low-grade gliomas. There appeared to be no benefit to higher doses, although unreported factors may impact interpretation of the results.

Tumor treating fields combined with a poly (adenosine diphosphate-ribose) polymerase inhibitor during radiotherapy for rapidly progressing IDH-wildtype diffuse astrocytoma: a case report.

A 57-year-old woman was diagnosed with IDH-wildtype (IDHwt) astrocytoma (World Health Organization grade II) with the molecular characteristics of glioblastoma. She underwent concurrent radiotherapy and chemotherapy according to the Stupp protocol in combination with a multi-target antiangiogenic drug and additional intrathecal chemotherapy using methotrexate. During treatment, the patient's tumor showed rapid progression. The chemotherapy with temozolomide was stopped and replaced with radiotherapy combined with tumor treating fields (TTF), the poly (adenosine diphosphate-ribose) polymerase (PARP) inhibitor niraparib, and anlotinib. After the radiotherapy was completed, the symptoms of increased intracranial pressure and epilepsy were well controlled. Considering the patient's tolerance to the treatment, the combined therapy of TTF and anlotinib was continued, and osimertinib, a third-generation epidermal growth factor receptor-tyrosine kinase inhibitor with good permeability of the blood-brain barrier, was added. The patient was regularly followed up and had no obvious adverse drug reactions. Head magnetic resonance imaging (plain scan + enhanced scan) suggested that the lesions were stable. For rapidly progressing glioblastomas or histological grade II/III IDHwt astrocytomas, the combination of TTF and a PARP inhibitor during radiotherapy may have a synergistic effect on tumor control and is well tolerated by patients.

Molecularly targeted treatment of recurrent anaplastic astrocytoma - a case report.

High-grade astrocytomas are malignant and aggressive, with limited treatment options. Treatment is geared not only toward increasing patient's overall survival but also in delaying or preventing neurological disability, a cause of significant morbidity. Increasingly, targeted and customized treatment approaches, especially for recurrent disease, are being explored. Here we present a successful outcome in a young patient with rapidly progressive disease who responded to targeted treatment based on genetic sequencing and circulating tumor DNA markers, given the inaccessibility of the tissue to biopsy. Molecular testing on tissue, serum or CSF may be helpful in identifying unique targets in these complex patients.

Interferon- and STING-independent induction of type I interferon stimulated genes during fractionated irradiation.

BACKGROUND: Improvement of radiotherapy efficacy requires better insight in the dynamic responses that occur during irradiation. Here, we aimed to identify the molecular responses that are triggered during clinically applied fractionated irradiation. METHODS: Gene expression analysis was performed by RNAseq or microarray analysis of cancer cells or xenograft tumors, respectively, subjected to 3-5 weeks of 5 × 2 Gy/week. Validation of altered gene expression was performed by qPCR and/or ELISA in multiple cancer cell lines as well as in pre- and on-treatment biopsies from esophageal cancer patients ( NCT02072720 ). Targeted protein inhibition and CRISPR/Cas-induced gene knockout was used to analyze the role of type I interferons and cGAS/STING signaling pathway in the molecular and cellular response to fractionated irradiation. RESULTS: Gene expression analysis identified type I interferon signaling as the most significantly enriched biological process induced during fractionated irradiation. The commonality of this response was confirmed in all irradiated cell lines, the xenograft tumors and in biopsies from esophageal cancer patients. Time-course analyses demonstrated a peak in interferon-stimulated gene (ISG) expression within 2-3 weeks of treatment. The response was accompanied by a variable induction of predominantly interferon-beta and/or -lambda, but blocking these interferons did not affect ISG expression induction. The same was true for targeted inhibition of the upstream regulatory STING protein while knockout of STING expression only delayed the ISG expression induction. CONCLUSIONS: Collectively, the presented data show that clinically applied fractionated low-dose irradiation can induce a delayed type I interferon response that occurs independently of interferon expression or STING signaling. These findings have implications for current efforts that aim to target the type I interferon response for cancer treatment.

Innumerable Meningiomas Arising in a Patient With Tuberous Sclerosis Complex Decades After Radiation Therapy.

Meningioma is the most common radiation-induced brain neoplasm, usually occurring after a latency of 20 - 35 years, with multiplicity in 10% of cases. Radiation-induced meningiomas (RIMs) have not previously been reported in patients with tuberous sclerosis complex (TSC), unlike their well-known occurrence in other familial tumor predisposition syndrome patients. We report a TSC patient who developed numerous intracranial meningiomas twenty five year after radiation therapy for subependymal giant cell astrocytoma (SEGA). Autopsy examination showed innumerable, coalescent, benign, meningothelial meningiomas, WHO grade 1, ranging in size from 0.2 cm to 3.3 cm. Autopsy also showed small residual SEGA, radiation-induced cerebral vasculopathy, and classic TSC features including several small subependymal nodules ("candle gutterings"), white matter radial heterotopia, facial angiofibromas, dental enamel pitting, one ash leaf spot, and multiple hepatic and renal angiomyolipomas. Next-generation sequencing analysis utilizing a 500+ gene cancer panel demonstrated chromosomal loss involving the majority of chromosome 22, including the NF2 gene locus, as well as a truncating nonsense mutation in TSC1 p. R509*. While TSC patients rarely require radiation therapy, this striking case suggests that patients with TSC should be monitored closely if cranial therapeutic radiation is administered.

Radiotherapy Plus Procarbazine, Lomustine, and Vincristine Versus Radiotherapy Plus Temozolomide for IDH-Mutant Anaplastic Astrocytoma: A Retrospective Multicenter Analysis of the French POLA Cohort.

BACKGROUND: IDH-mutant anaplastic astrocytomas (AAs) are chemosensitive tumors for which the best choice of adjuvant chemotherapy between procarbazine, lomustine, and vincristine (PCV) or temozolomide (TMZ) after radiotherapy (RT) remains unclear. METHODS: In a large cohort of patients with histologically proven 2016 World Health Organization classification AA with IDH1/2 mutations included in the French national POLA cohort (n = 355), the primary objective was to compare progression-free survival (PFS) between the two treatment regimens (n = 311). Secondary endpoints were overall survival (OS), progression type, pseudoprogression rate, and toxicity. RESULTS: The 4-year PFS in the RT + PCV arm was 70.8% versus 53.5% in the RT + TMZ arm, with a hazard ratio (HR) of 0.58 (95% confidence interval [CI], 0.38-0.87; p = .0074) in univariable analysis and 0.63 (95% CI, 0.41-0.97; p = .0348) in multivariable analysis. The 4-year OS in the RT + PCV arm was 84.3% versus 76.6% in the RT + TMZ arm, with an HR of 0.57 (95% CI, 0.30-1.05; p = .0675) in univariable analysis. Toxicity was significantly higher in the RT + PCV arm with more grade ≥3 toxicity (46.7% vs. 8.6%, p < .0001). CONCLUSION: RT + PCV significantly improved PFS compared with RT + TMZ for IDH-mutant AA. However, RT + TMZ was better tolerated. IMPLICATIONS FOR PRACTICE: In the absence of fully conducted randomized trials comparing procarbazine, lomustine, and vincristine (PCV) with temozolomide (TMZ) in adjuvant treatment after radiotherapy (RT) for the management of IDH-mutant anaplastic astrocytoma (AA) and a similar level of evidence, these two chemotherapies are both equally recommended in international guidelines. This study in a national cohort of IDH-mutant AA defined according the 2016 World Health Organization (WHO) classification shows for the first time that the RT + PCV regimen significantly improves progression-free survival in comparison with the RT + TMZ regimen. Even if at the time of analysis the difference in overall survival was not significant, this result provides new evidence for the debate about the chemotherapy regimen to prescribe in adjuvant treatment to RT for WHO 2016 IDH-mutant AA.

Radiotherapy in adult low-grade glioma: nationwide trends in treatment and outcomes.

BACKGROUND: Management of WHO grade II gliomas (LGG) can include a combination of observation, surgery, radiotherapy (RT), and chemotherapy; however, optimal management remains unclear in regards to RT. OBJECTIVE: The current study seeks to investigate the usage of RT in LGG and its effect on survival outcomes. METHODS: Patients with diagnosis codes specific for LGG were queried from the National Cancer Database (NCDB) during the years 2004-2016. Kaplan-Meier curves with log-rank testing, univariate and multivariate Cox regression analysis, and comparisons of estimated 3- and 7-year survival were performed to investigate the effect of RT on overall survival. RESULTS: 19,382 patients with LGG were identified with histologically confirmed disease. Kaplan-Meier testing demonstrated RT impacted survival in patients undergoing biopsy or no surgery (p < 0.0001), no chemotherapy (p < 0.0001), and in regimens with early RT (p < 0.0001) and high-dose RT (p < 0.0001). Cox multivariate regression demonstrated RT and age less than 40 (HR 0.93, 95% CI 0.89-0.97, p = 0.001), no chemotherapy (HR 0.82, 95% CI 0.77-0.87, p < 0.001), and astrocytoma histology (HR 0.72, 95% CI 0.66-0.79, p < 0.001) were associated with improved survival. 3-year survival of RT versus non-RT groups showed increased survival rates for age less than 40 years (+ 5.7%, p < 0.0001), no surgery or biopsy (+ 8.1%, p < 0.0001), no chemotherapy (+ 10.3%, p < 0.0001), mixed glioma (+ 6.7%, p < 0.0001), astrocytoma (+ 7.1%, p < 0.0001), and in regimens with early RT (+ 7.6%, p < 0.0001) and high-dose RT (+ 4.7%, p < 0.0001). CONCLUSION: This nationwide analysis of LGG patients found that RT was associated with improved survival outcomes in patients less than 40 years of age, with histology subtypes of astrocytoma and mixed glioma, undergoing biopsy or no surgery, and in regimens with early RT and high-dose RT.

[Lacunar stroke as a very late complication of radiotherapy: value of nuclear medicine techniques]. / Ictus lacunar como complicación muy tardía de la radioterapia: valor de las técnicas de medicina nuclear.

INTRODUCTION: Radiation therapy is a very useful treatment for central nervous systemS neoplasms. The time range of its complications is very wide; they appear even many years after its completion. These late complications behave clinically and radiologically similar to a relapse; a functional diagnostic study with radioactive isotopes can help to make a therapeutic decision. CASE REPORT: A male suddenly presented deficient neurological symptoms in the same site where he received radiation therapy 25 years earlier for a pilocytic astrocytoma. The MRI findings suggested a lacunar stroke but a finding in the perfusion sequence forced us to be more precise in the diagnosis. A PET-CT 11C-methionine was performed which showed an increased uptake compatible with neoplasia. The spontaneous regressive evolution of the symptoms inclined us to take a conservative attitude. Lacunar ictus was confirmed on MRI three months later. CONCLUSIONS: The reappearance of neurological symptoms years after radiotherapy of a brain neoplasm poses a diagnostic dilemma. Current diagnostic techniques are very accurate but present false positives. The various nuclear medicine techniques, in particular PET-CT 11C-methionine, are a diagnostic aid. With the presentation of this case we intend to draw attention to one of the late complications of radiation therapy and the various differential diagnoses. Diagnostic and therapeutic advances have increased the life expectancy of cancer patients, so these late complications are expected to be more frequent.

TITLE: Ictus lacunar como complicación muy tardía de la radioterapia: valor de las técnicas de medicina nuclear.Introducción. La radioterapia es un tratamiento de gran utilidad en las neoplasias del sistema nervioso central. El rango temporal de sus complicaciones es muy amplio, ya que aparecen incluso muchos años más tarde de haberla finalizado. Estas complicaciones tardías se comportan clínica y radiológicamente de forma similar a una recidiva; un estudio funcional diagnóstico con isótopos radiactivos puede ayudar a tomar una decisión terapéutica. Caso clínico. Varón que presentó de forma brusca sintomatología neurológica deficitaria en la misma localización donde 25 años antes había recibido radioterapia por un astrocitoma pilocítico. La resonancia magnética sugería un ictus lacunar, pero un hallazgo en la secuencia de perfusión obligaba a ser más preciso en el diagnóstico. Una tomografía por emisión de positrones-tomografía computarizada (PET-TC) con C11-metionina mostró un aumento de captación compatible con neoplasia. La evolución espontánea regresiva de los síntomas inclinó a tomar una actitud conservadora. Una resonancia magnética realizada tres meses más tarde confirmó el ictus lacunar. Conclusiones. La reaparición de síntomas neurológicos años más tarde de la radioterapia de una neoplasia cerebral supone un dilema diagnóstico. Las técnicas diagnósticas actuales son muy precisas, pero presentan falsos positivos. Las distintas técnicas de medicina nuclear, en concreto la PET-TC con C11-metionina, suponen una ayuda diagnóstica. Con este caso se pretende llamar la atención sobre una de las complicaciones tardías de la radioterapia y los distintos diagnósticos diferenciales. Los avances diagnósticos y terapéuticos han aumentado la esperanza de vida de los pacientes oncológicos, con lo que estas complicaciones tardías se prevén más frecuentes.

＜Editors' Choice＞ Impact of maintenance of postoperative performance status on survival in elderly patients over 70 with high-grade astrocytoma.

This study aimed to identify the elderly generation with the worst prognoses for high-grade astrocytoma and find independent predictors of good outcomes. We conducted a retrospective analysis of 91 patients, ≥65 years old, with anaplastic astrocytoma or glioblastoma. Progression-free survival (PFS) and overall survival (OS) were calculated using the Kaplan-Meier method and compared using log-rank test or multivariate Cox regression analysis. We included 21 (23%) and 70 (77%) patients aged 65-69 years and ≥70 years. In the two generations, significant differences were found in the Charlson comorbidity index, extent of resection, chemoradiotherapy (CRT) as adjuvant therapy, and radiation dose (all P < 0.05). The median PFS was 9.9 and 6.9 months in patients aged 65-69 and ≥70 years (P = 0.10). The median OS was 22.8 and 11.6 months in patients aged 65-69 and ≥70 years (P = 0.009). In the multivariate analyzes in patients ≥70 years, only postoperative Karnofsky performance status (KPS) scores ≥70 were significantly related to prolonged PFS (hazard ratio [HR]: 0.48, P = 0.04), and postoperative KPS, CRT as adjuvant therapy, and salvage therapy were significantly related to prolonged OS (HR: 0.45, P = 0.03, HR: 0.38, P = 0.002, and HR: 0.43, P = 0.01, respectively). In conclusion, in patients ≥70 with high-grade astrocytoma, OS was significantly shorter compared to those aged 65-69. Postoperative KPS score was significantly related to prolonged PFS and OS. Postoperative CRT and salvage therapy at recurrence may be effective in the selected elderly.

Repeat Radiation in the Brain: Managing Patients With Locally Recurrent Glioma.

Treatment of recurrent gliomas is especially challenging, as many of these patients have previously been treated with extensive surgery, radiation, or systemic therapy. Due to this, the optimum therapy for patients with recurrent glioma is controversial, with widely variable practice patterns. In this opinion piece, a multidisciplinary panel of experts provides rationale for their treatment approach in a patient with recurrent glioma following subtotal resection with adjuvant chemoradiation for an anaplastic astrocytoma. In summary, the consensus of the panel was to recommend re-resection if possible with hypofractionated radiotherapy schedules, with re-irradiation and systemic therapy as directed by a multidisciplinary team through repeat analysis of the tumor specimen for an updated mutational burden.

Risk stratification in pediatric low-grade glioma and glioneuronal tumor treated with radiation therapy: an integrated clinicopathologic and molecular analysis.

BACKGROUND: Management of unresectable pediatric low-grade glioma and glioneuronal tumor (LGG/LGGNT) is controversial. There are no validated prognostic features to guide use of radiation therapy (RT). Our study aimed to identify negative prognostic features in patients treated with RT using clinicopathologic and molecular data and validate these findings in an external dataset. METHODS: Children with non-metastatic, biopsy-proven unresectable LGG/LGGNT treated with RT at a single institution between 1997 and 2017 were identified. Recursive partitioning analysis (RPA) was used to stratify patients into low- and high-risk prognostic groups based on overall survival (OS). CNS9702 data were used for validation. RESULTS: One hundred and fifty patients met inclusion criteria. Median follow-up was 11.4 years. RPA yielded low- and high-risk groups with 10-year OS of 95.6% versus 76.4% (95% CI: 88.7%-98.4% vs 59.3%-87.1%, P = 0.003), respectively. These risk groups were validated using CNS9702 dataset (n = 48) (4-year OS: low-risk vs high-risk: 100% vs 64%, P < 0.001). High-risk tumors included diffuse astrocytoma or location within thalamus/midbrain. Low-risk tumors included pilocytic astrocytoma/ganglioglioma located outside of the thalamus/midbrain. In the subgroup with known BRAF status (n = 49), risk stratification remained prognostic independently of BRAF alteration (V600E or fusion). Within the high-risk group, delayed RT, defined as RT after at least one line of chemotherapy, was associated with a further decrement in overall survival (P = 0.021). CONCLUSION: A high-risk subgroup of patients, defined by diffuse astrocytoma histology or midbrain/thalamus tumor location, have suboptimal long-term survival and might benefit from timely use of RT. These results require validation.

Adult Pilocytic Astrocytomas: A Brazilian Series.

OBJECTIVE: Pilocytic astrocytoma (PA) is rare in adults comprising 5.1% of the primary central nervous system tumors. The aim is to describe the first Brazilian series of adult patients with PA and compare its features with the available literature. METHODS: We retrospectively review all patients 18 years or older with PA from our institution's database from 1991 to 2018. We analyzed information regarding clinical presentation, location, imaging features, extent of resection, adjuvant treatments, and follow-up. RESULTS: Twenty-three patients with PA were analyzed: 60.9% male; median age 26 years. The most frequent symptoms were headache (34.8%) and seizure (26.1%). Temporal and parietal lobes were the most common locations, 21.7% each. All patients underwent a surgical procedure, gross total resection in 40.9%, subtotal resection in 22.7%, and biopsy in 27.3%. Adjuvant treatment with radiotherapy was performed in 2 patients. Only 4 patients had disease progression, 2 after gross total resection and 2 after subtotal resection. They were all alive and without evidence of new progression at the last follow-up (October 2018). Median overall survival was not reached after a median follow-up time of 88.9 months. CONCLUSIONS: This is the first Brazilian series regarding adults with PA, and our patients had a favorable outcome as reported in recent literature reviews. The tumor's prevalence reduces within older patients and supratentorial lesions are more frequent, especially on the temporal lobe. There was no significant relationship between location and progression, although according to the literature the extent of resection remains the most important prognostic factor.

Pattern of failure in anaplastic glioma patients with an IDH1/2 mutation.

PURPOSE: The current study aimed to assess patterns of failure (PoF) in anaplastic glioma (AG) patients managed with intensity-modulated radiation therapy (IMRT) and their relationship to molecular subtype. METHODS: The outcomes of AG patients managed between 2008 and 2014 and entered into a prospective database were assessed, including PoF. AG was initially defined using the WHO 2007 classification, but for analysis, patients were subsequently recategorised based on WHO 2016 as anaplastic oligodendroglioma (AOD), astrocytoma isocitrate dehydrogenase (IDH) mutant (AAmut) or astrocytoma IDH wildtype (AAwt). Management involved IMRT and temozolomide (TMZ), including from 2011 patients with an IDH mutation (IDHmut) planned with 18F-fluoroethyltyrosine (FET) and 18F-fluorodeoxyglucose (FDG) positron-emission tomography (PET). PoF was local, marginal or distant in relation to the IMRT volume. Relapse-free survival (RFS) was calculated from the start of IMRT. RESULTS: A total of 156 patients were assessed, with median follow-up of 5.1 years. Of these patients, 75% were IDHmut, 44% were managed at first or later relapse and 73% received TMZ. Relapse occurred in 68 patients, with 6­year RFS of 75.0, 48.8 and 2.5% for AOD, AAmut and AAwt, respectively (p < 0.001). There was a component of local relapse in 63%, of marginal relapse in 19% and of distant relapse in 37% of relapses. Isolated local, marginal and distant relapse was evident in 51, 9 and 22%, respectively. A distant relapse pattern was more frequent in IDHmut compared to IDHwt patients (26% vs. 45%, p = 0.005), especially within the first 2 years post-IMRT. In multivariate analysis, distant relapse remained associated with AAmut (p < 0.002) and delayed IMRT until the second relapse (p < 0.001). CONCLUSION: Although patients with IDH-mutated AG have improved outcomes, there was a higher proportion of distant relapses occurring during the 2 years after IMRT.

An open invitation to join the Pediatric Proton/Photon Consortium Registry to standardize data collection in pediatric radiation oncology.

OBJECTIVE: The Pediatric Proton/Photon Consortium Registry (PPCR) is a comprehensive data registry composed of pediatric patients treated with radiation. It was established to expedite outcomes-based research. The attributes which allow the PPCR to be a successful collaboration are reviewed. METHODS AND MATERIALS: Current eligibility criteria are radiotherapy patients < 22 years treated at one of the 15 US participating institutions. Detailed health and treatment data are collected about the disease presentation and treatment exposures, and annually thereafter, in REDCap (Research Electronic Data Capture). DICOM (Digital Imaging and Communications in Medicine) imaging and radiation plans are collected through MIM/MIMcloud. An optional patient-reported quality-of-life (PedsQL) study is administered at 10 sites. RESULTS: Accrual started October 2012 with 2,775 participants enrolled as of 25 July 2019. Most patients, 62.0%, were treated for central nervous system (CNS) tumors, the most common of which are medulloblastoma (n = 349), ependymoma (n = 309), and glial/astrocytoma tumors (n = 279). The most common non-CNS diagnoses are rhabdomyosarcoma (n = 284), Ewing's sarcoma (n = 153), and neuroblastoma (n = 130). While the majority of participants are US residents, 18.7% come from 36 other countries. Over 685 patients participate in the PedsQL study. CONCLUSIONS: The PPCR is a valuable research platform capable of answering countless research questions that will ultimately improve patient care. Centers outside of the USA are invited to participate directly or may engage with the PPCR to align data collection strategies to facilitate large-scale international research. ADVANCES IN KNOWLEDGE: For investigators looking to carry out research in a large pediatric oncology cohort or interested in registry work, this paper provides an updated overview of the PPCR.