"One of the Grand Works of the World": Walt Whitman's Advocacy for the Brooklyn Waterworks, 1856-59.

When the Brooklyn Waterworks opened in 1859, it was one of America's most advanced water and sewer systems. Yet after Brooklyn was annexed by New York City, the waterworks' history slipped into obscurity, despite having a now-famous champion: the "poet of America," Walt Whitman, whose brother worked on the project. This article shows the Brooklyn poet's fierce, multiyear lobbying effort for the waterworks in various newspapers and introduces a wealth of newly recovered Whitman writings on the issue. As a journalist, Whitman exemplifies the nineteenth-century press as an intermediary between expert engineers and popular readers. The poet brought precise expertise, translated engineers' technical arguments into everyday language for his readers, and fought the resulting day-to-day political battles over construction in print. Whitman, then, is an underappreciated case study of the confluence of technology, public health, and local journalism.

NRG brain tumor specialists consensus guidelines for glioblastoma contouring.

INTRODUCTION: NRG protocols for glioblastoma allow for clinical target volume (CTV) reductions at natural barriers; however, literature examining CTV contouring and the relevant white matter pathways is lacking. This study proposes consensus CTV guidelines, with a focus on areas of controversy while highlighting common errors in glioblastoma target delineation. METHODS: Ten academic radiation oncologists specializing in brain tumor treatment contoured CTVs on four glioblastoma cases. CTV expansions were based on NRG trial guidelines. Contour consensus was assessed and summarized by kappa statistics. A meeting was held to discuss the mathematically averaged contours and form consensus contours and recommendations. RESULTS: Contours of the cavity plus enhancement (mean kappa 0.69) and T2-FLAIR signal (mean kappa 0.74) showed moderate to substantial agreement. Experts were asked to trim off anatomic barriers while respecting pathways of spread to develop their CTVs. Submitted CTV_4600 (mean kappa 0.80) and CTV_6000 (mean kappa 0.81) contours showed substantial to near perfect agreement. Simultaneous truth and performance level estimation (STAPLE) contours were then reviewed and modified by group consensus. Anatomic trimming reduced the amount of total brain tissue planned for radiation targeting by a 13.6% (range 8.7-17.9%) mean proportional reduction. Areas for close scrutiny of target delineation were described, with accompanying recommendations. CONCLUSIONS: Consensus contouring guidelines were established based on expert contours. Careful delineation of anatomic pathways and barriers to spread can spare radiation to uninvolved tissue without compromising target coverage. Further study is necessary to accurately define optimal target volumes beyond isometric expansion techniques for individual patients.

Proton Radiotherapy for Midline Central Nervous System Lesions: A Class Solution.

OBJECTIVE: Midline and central lesions of the brain requiring conventional radiotherapy (RT) present complex difficulties in dose avoidance to organs at risk (OAR). In either definitive or adjuvant settings, proper RT coverage of these lesions involves unnecessary treatment of large volumes of normal brain. We propose a class solution for these lesions using proton radiotherapy (PrT). MATERIALS AND METHODS: The records of the Indiana University Health Proton Therapy Center were reviewed for patients presenting between January 1, 2005 and October 1, 2013 with midline central nervous system (CNS) lesions. Twenty-four patients were identified. After Institutional Review Board approval was granted, their dosimetry was reviewed for target volume doses and OAR dose avoidance. RESULTS: For these cases, meningiomas were the most common histology (8 cases), and next most prevalent were craniopharyngiomas (6 cases). The others were various different deep midline brain tumors (10 cases). In all cases, fields formed by vertex and/or anterior/posterior superior oblique PrT beams along the midsagittal plane were used to provide coverage with minimal dose to the brain stem or to the cerebral hemispheres. The median prescribed dose to the planning target volume for treating these patients was 54.0 Gy RBE (range 48.6-62.5) with a mean dose of 53.5 Gy RBE. The average of the mean doses to the brain stems using these fields in the 24 plans was 18.4 Gy RBE (range 0.0-44.7). Similarly, the average of the mean doses to the hippocampi was 15.8 Gy RBE (range 0.0-52.6). CONCLUSIONS: We consider these patients to be optimally treated with PrT. The use of modified midsagittal PrT schemas allows for the treatment of midline CNS lesions with sparing of most of the uninvolved brain.

Proton therapy for atypical meningiomas.

We report clinical outcomes of proton therapy in patients with World Health Organization grade 2 (atypical) meningiomas. Between 2005 and 2013, 22 patients with atypical meningiomas were treated to a median dose of 63 Gy (RBE) using proton therapy, as an adjuvant therapy after surgery (n = 12) or for recurrence or progression of residual tumor (n = 10). Six patients had presumed radiation-induced meningiomas, but none had received prior radiotherapy for their meningioma. The median follow-up time after radiation was 39 months (range 7-104) and all patients remain alive at last follow-up. The 5-year estimate of local control was 71.1% (95% CI 49.3-92.9%). The 5-year estimate of local control was 87.5% following a radiation dose >60 Gy (RBE), compared to 50.0% for ≤ 60 Gy (RBE) (p = 0.038). The 5-year estimate of neuraxis dissemination was 5% (95% CI 0-14.6%) and 6.2% (95% CI 0-18.2%) for metastases outside of the central nervous system. Radiation necrosis was observed in one patient with a history of prior cranial irradiation. Fractionated proton therapy was associated with favorable tumor control rates for grade 2 meningiomas. Prospective studies are needed to define the optimal radiation dose for high-grade meningiomas.

Local control and toxicity outcomes in brainstem metastases treated with single fraction radiosurgery: is there a volume threshold for toxicity?

Gamma Knife Radiosurgery (GKRS) has been reported in the treatment of brainstem metastases while dose volume toxicity thresholds remain mostly undefined. A retrospective review of 52 brainstem metastases in 44 patients treated with GKRS was completed. A median dose of 18 Gy (range 10-22 Gy) was prescribed to the tumor margin (median 50 % isodose). 25 patients had undergone previous whole brain radiation therapy. Toxicity was graded by the LENT-SOMA scale. Mean and median follow-up was 10 and 6 months. Only 3 of the 44 patients are living. Multiple brain metastases were treated in 75 % of patients. Median size of lesions was 0.134 cc, (range 0.013-6.600 cc). Overall survival rate at 1 year was 32 % (95 % CI 51.0-20.1 %) with a median survival time of 6 months (95 % CI 5.0-16.5). Local control rate at 6 months and 1 year was 88 % (95 % CI 70-95 %) and 74 % (95 % CI 52-87 %). Cause of death was neurologic in 17 patients, non-neurologic in 20 patients, and unknown in four. Four patients experienced treatment related toxicities. Univariate analysis of tumor volume revealed that volume greater than 1.0 cc predicted for toxicity. A strategy of using lower marginal doses with GKRS to brain stem metastases appears to lead to a lower local control rate than seen with lesions treated within the standard dose range in other locations. Tumor size greater than 1.0 cc predicted for treatment-related toxicity.

Outpatient management of vascular access devices in children receiving radiotherapy: complications and morbidity.

BACKGROUND: When treating children with cancer, long-term venous access is critical. This is especially true in the context of children receiving daily radiation therapy (RT) under general anesthesia. We have previously reported <0.1% risk of complications in complications in over 4,040 pediatric treatments under general anesthesia in our outpatient facility. Here, we present our experience with venous catheter access techniques in children receiving daily proton RT. PROCEDURE: After Institutional Review Board approval, we reviewed our center's records between September 9, 2004 and October 23, 2012 with respect to complications and morbidity of indwelling catheters in our pediatric patients. RESULTS: Vascular access device (VAD) types included: 110 patients with indwelling port-a-cath (PAC), 34 PICC line devices, and 34 central venous catheter (CVC) devices in 170 patients. Median catheter life during RT was 43 days (range 1-86 days) with a total of 7,169 total catheter days while patients received RT. A 14% PAC complication rate included negative blood return (6.3%) and infection (3.6%). Complication rates for PICC and CVC access devices were 38% and 20.5%, respectively (χ(2) P = 0.007 when compared with PAC). Most frequent complications for PICC lines were no blood return (11.7%), and infection or occlusion (8.8% each). CVC complications were breakage (8.8%) and infection (8.8%). Access device replacement rates were 3.6% (PAC), 14.7% (PICC), and 8.8% (CVC). CONCLUSIONS: In the outpatient delivery of RT to children, indwelling ports provide greater convenience, less likelihood of infection or complication, and greater durability than PICC or CVC devices.

Oral and dental late effects in survivors of childhood cancer: a Children's Oncology Group report.

PURPOSE: Multi-modality therapy has resulted in improved survival for childhood malignancies. The Children's Oncology Group Long-Term Follow-Up Guidelines for Survivors of Childhood, Adolescent, and Young Adult Cancers provide practitioners with exposure- and risk-based recommendations for the surveillance and management of asymptomatic survivors who are at least 2 years from completion of therapy. This review outlines the pathophysiology and risks for oral and dental late effects in pediatric cancer survivors and the rationale for oral and dental screening recommended by the Children's Oncology Group. METHODS: An English literature search for oral and dental complications of childhood cancer treatment was undertaken via MEDLINE and encompassed January 1975 to January 2013. Proposed guideline content based on the literature review was approved by a multi-disciplinary panel of survivorship experts and scored according to a modified version of the National Comprehensive Cancer Network "Categories of Consensus" system. RESULTS: The Children's Oncology Group oral-dental panel selected 85 relevant citations. Childhood cancer therapy may impact tooth development, salivary function, craniofacial development, and temporomandibular joint function placing some childhood cancer survivors at an increased risk for poor oral and dental health. Additionally, head and neck radiation and hematopoietic stem cell transplantation increase the risk of subsequent malignant neoplasms in the oral cavity. Survivors require routine dental care to evaluate for potential side effects and initiate early treatment. CONCLUSIONS: Certain childhood cancer survivors are at an increased risk for poor oral and dental health. Early identification of oral and dental morbidity and early interventions can optimize health and quality of life.

Definitive treatment of leptomeningeal spinal metastases in children.

BACKGROUND: Uniquely in children, the existence of leptomeningeal spinal metastases does not confer a uniformly grave prognosis. Although the radiation tolerance of the spinal cord is of significant concern in these cases, the chemo- and radiosensitivity of these lesions argues for an aggressive approach where possible. METHODS: The records of the Indiana University Health Proton Therapy Center were reviewed for patients undergoing proton beam therapy with curative intent for LSM between January 1, 2004 and July 7, 2012. Patients with microscopic disease only on LP were not included. Particulars of therapy, including dose, field sizes, toxicities, and outcomes were collated. RESULTS: Twenty-two children received therapy as described, of median age 5 years (range 1.1-17.1). Patients had medulloblastoma (n = 9), ATRT (n = 4), ependymoma, and PNET (n = 3 each). Five lesions (23%) were chemo-recurrent, though no patient had prior radiation to the spine. Median follow-up was 14 months (range 4-33) for all living patients. Fifteen (68%) children continued to have local control at last follow-up visit. Median dose was 37.8 Gy (range 21.6-54 Gy). Eight patients with chemo-recurrent disease or diffuse cord seeding did poorly, with local control and overall survival achieved in four. The 12-month overall survival was 68% with grade 1 skin erythema as the most frequent toxicity. CONCLUSIONS: We describe a cohort of LSM patients treated with RT with definitive intent, and the only available data from the proton environment. Durable response is possible for these children in over two-thirds of cases. Significant toxicity was infrequent using proton radiotherapy and these fractionation schemes.

Initial experience with bendamustine in patients with recurrent primary central nervous system lymphoma: a case report.

Novel therapeutic options for patients with recurrent primary central nervous system lymphoma (RPCNSL) are needed. Bendamustine, a bifunctional purine analog/alkylating agent, is approved for use in patients with progressive systemic indolent non-Hodgkin's B-cell lymphomas. Limited data suggests that bendamustine may partition into the brain in the setting of a disrupted blood-brain barrier. This report describes the first known experience of patients with RPCNSL treated with bendamustine. Therapy was well-tolerated and best response was noted as stable disease after eight cycles of bendamustine followed by a subsequent local systemic recurrence found at five months follow-up. CNS involvement in this patient remained stable 20 + months post-bendamustine treatment. Based on our observations, further neuropharmacokinetic and efficacy studies with bendamustine may be warranted in this patient population.

Phase II study of Ginkgo biloba in irradiated brain tumor patients: effect on cognitive function, quality of life, and mood.

UNLABELLED: Ginkgo biloba has been reported to improve cognitive function in older adults and patients with Alzheimer's disease and multi-infarct dementia. We conducted an open-label phase II study of this botanical product in symptomatic irradiated brain tumor survivors. Eligibility criteria included: life expectancy ≥30 weeks, partial or whole brain radiation ≥6 months before enrollment, no imaging evidence of tumor progression in previous 3 months, or stable or decreasing steroid dose, and no brain tumor treatment planned while on study. The Ginkgo biloba dose was 120 mg/day (40 mg t.i.d.) for 24 weeks followed by a 6-week washout period. Assessments performed at baseline, 12, 24 (end of treatment), and 30 weeks (end of washout) included KPS, Functional Assessment of Cancer Therapy-Brain (FACT-Br), Profile of Mood States, Mini-Mental Status Exam, Trail Making Test Parts A (TMT-A) and B (TMT-B), Digit Span Test, Modified Rey Osterrieth Complex Figure (ROCF), California Verbal Learning Test Part II, and the F-A-S Test. RESULTS: Of the 34 patients enrolled on study, 23 (68 %) completed 12 weeks of treatment and 19 (56 %) completed 24 weeks of treatment. There were significant improvements at 24 weeks in: executive function (TMT-B) (p = 0.007), attention/concentration (TMT-A) (p = 0.002), and non-verbal memory (ROCF-immediate/delayed recall) (p = 0.001/0.002), mood (p = 0.002), FACT-Br subscale (p = 0.001), and the FACT physical subscale (p = 0.003). CONCLUSIONS: Some improvement in quality of life and cognitive function were noted with Ginkgo biloba. However, treatment with Ginkgo biloba was associated with a high dropout rate.

Breast cancer subtype affects patterns of failure of brain metastases after treatment with stereotactic radiosurgery.

We investigate the variance in patterns of failure after Gamma Knife™ radiosurgery (GKRS) for patients with brain metastases based on the subtype of the primary breast cancer. Between 2000 and 2010, 154 breast cancer patients were treated with GKRS for brain metastases. Tumor subtypes were approximated based on hormone receptor (HR) and HER2 status of the primary cancer: Luminal A/B (HR+/HER2(-)); HER2 (HER2+/HR(-)); Luminal HER2 (HR+/HER2+), Basal (HR(-)/HER2(-)), and then based on HER2 status alone. The median follow-up period was 54 months. Kaplan-Meier method was used to estimate survival times. Multivariable analysis was performed using Cox regression models. Median number of lesions treated was two (range 1-15) with a median dose of 20 Gy (range 9-24 Gy). Median overall survival (OS) was 7, 9, 11 and 22 months for Basal, Luminal A/B, HER2, and Luminal HER2, respectively (p = 0.001), and was 17 and 8 months for HER2+ and HER(-) patients, respectively (p < 0.001). Breast cancer subtype did not predict time to local failure (p = 0.554), but did predict distant brain failure rate (76, 47, 47, 36 % at 1 year for Basal, Luminal A/B, HER2, and Luminal HER2 respectively, p < 0.001). An increased proportion of HER2+ patients experienced neurologic death (46 vs 31 %, p = 0.066). Multivariate analysis revealed that HER2+ patients (p = 0.007) independently predicted for improved survival. Women with basal subtype have high rates of distant brain failure and worsened survival. Our data suggest that differences in biologic behavior of brain metastasis occur across breast cancer subtypes.

Patterns of failure after treatment of atypical meningioma with gamma knife radiosurgery.

Atypical meningiomas have poor local control with emerging literature indicating the use of radiosurgery in treatment. The purpose of this study was to evaluate clinical outcomes including local control and failure pattern after Gamma Knife radiosurgery (GKRS) and factors that may affect these outcomes. Between 1999 and 2008, 24 patients were treated with GKRS as either primary or salvage treatment for pathologically proven atypical meningiomas. Treatment failures were determined by serial magnetic resonance imaging. A median marginal dose of 14 Gy was used (range 10.5-18 Gy). Overall local control rates at 1, 2, and 5 years were 75, 51, and 44%, respectively. With median follow-up time of 42.5 months, 14 of 24 patients experienced a treatment failure at time of last follow-up. Eight recurrences were in-field, four were marginal failures, and two were distant failures. Wilcoxon analysis revealed that the conformality index (CI) was a significant predictor of local recurrence (P = 0.04). CI did not predict for distant recurrences (P = 0.16). On multivariate analysis evaluating factors predicting progression free survival, dose >14 Gy was found to be statistically significant (P = 0.01). There appears to be a dose response using GKRS beyond 14 Gy but given the suboptimal local control rates in this study, higher doses may still be needed to obtain better local control.

A phase II trial of thalidomide and procarbazine in adult patients with recurrent or progressive malignant gliomas.

Thalidomide and procarbazine have demonstrated single agent activity against malignant gliomas (MG). We evaluated the combination of thalidomide and procarbazine with a single arm phase II trial in adults with recurrent or progressive MG. Procarbazine was given at a dose of 250 mg/m(2)/d × 5day q 28 days. Thalidomide was administered at a dose of 200 mg/day continuously. Intrapatient dose escalation of thalidomide was attempted (increase by 100 mg/day weekly as tolerated) to a maximum of 800 mg/day. The primary outcome was tumor response, assessed by MRI and CT. Secondary outcomes were progression free survival (PFS), overall survival (OS) and toxicity. In addition, quality of life questionnaires were performed at baseline and prior to each odd cycle in all treated patients. Eighteen patients (median age of 50) were accrued and received a total of 36 cycles (median 2) of therapy. The median maximum thalidomide dose achieved was 400 mg (range 0-800). No complete or partial responses were seen. One patient (6%) experienced stable disease, fourteen (78%) progressed as best response and three (17%) were not evaluable for response. Median time to progression was 2.1 months (95% CI, 1.5-2.5). Seventeen patients have died (one patient lost to follow-up after progression); median survival from enrollment was 7.6 months (95% CI, 3.5-9.4). Grade 3/4 drug related toxicity was minimal. Quality of life diminished over time. The combination of thalidomide and procarbazine demonstrated no efficacy in this trial.

Toxicity and efficacy of the acetylcholinesterase (AChe) inhibitor donepezil in childhood brain tumor survivors: a pilot study.

BACKGROUND: Neurocognitive deficits are a recognized late effect of curative brain tumor therapy. We evaluated the feasibility, tolerance, and impact of a pilot pharmacologic intervention with the acetylcholinesterase (AChe) inhibitor, donepezil, in pediatric brain tumor (BT) survivors at risk for neurocognitive dysfunction. PROCEDURE: A single institution open-label pilot study was conducted in childhood BT survivors: ≥1 year from cancer treatment; and who received >23.5 Gy cranial radiation therapy (RT). Toxicity, adherence and neurocognitive outcomes were evaluated at baseline and serially during 24 weeks of donepezil, and following a 12-week washout period off drug. RESULTS: From a pool of subjects, 13 were successfully contacted and screened, and 11 met all eligibility criteria to initiate donepezil at a median of 4.7 (1.9-11.9) years from RT. Seventy-two percent of patients completed the 24-week drug study visit. Despite transient gastrointestinal toxicity (vomiting and diarrhea) in 30% of patients there was no weight loss on donepezil. Significant improvement in performance was noted at 24 weeks on the Dellis-Kaplan Executive Function (D-KEF) Tower test (P < 0.001), the Wide Range Assessment of Memory and Learning, 2nd Edition (WRAML-2) Visual memory (P = 0.007), and the Number/Letter task (P = 0.018). CONCLUSIONS: Donepezil was well tolerated among childhood BT survivors who had received substantial prior therapy. Based on improved executive function and memory performance in this pilot trial, a randomized placebo controlled trial of this pharmacologic agent is warranted to fully evaluate its efficacy in remediating neurocognitive dysfunction.

Gamma knife radiosurgery in the treatment of tumor-related facial pain.

BACKGROUND: Intracranial neoplasms can cause pain similar to trigeminal neuralgia. Literature regarding radiosurgery for this is limited. We present a retrospective review of patients with tumor-related facial pain from benign lesions treated with gamma knife radiosurgery (GKRS) at Wake Forest University. OBJECTIVES: The primary objectives were to determine long-term pain relief and predictive factors for pain alleviation. METHODS: We reviewed 515 patients treated with GKRS for benign meningioma, vestibular schwannoma or trigeminal schwannoma between August 1999 and August 2010. Twenty-one eligible patients had tumor-related facial pain prior to GKRS. The median marginal tumor dose was 12 Gy. Long-term pain relief data were obtained by chart review and telephone interview. RESULTS: The median follow-up for symptom evaluation was 3.8 years. Seventeen of 21 patients (81%) experienced a Barrow Neurological Institute (BNI) score of I-III at 6 months following GKRS. Kaplan-Meier estimates of freedom from BNI IV-V relapse were 66% at 1 year and 53% at 2 years. No pain relapses occurred after 2 years. CONCLUSION: GKRS of benign lesions is a noninvasive option for patients with tumor-related facial pain. Pain relief is modest, with the majority of pain relapses occurring within 2 years and approximately one half of patients maintaining relief beyond 2 years.

Radiation-induced adult medulloblastoma: a two-case report and review of the literature.

Radiation-induced medulloblastoma is an exceedingly rare phenomenon for which treatment standards have not been established. The literature suggests that these tumors are high grade with aggressive behavior. We report two cases of radiation-induced medulloblastoma which have been treated with full dose re-irradiation with curative intent. In both cases, treatment toxicity and tumor progression proved to be insurmountable obstacles. Further reports are necessary in order to fully characterize this clinical entity so that more effective therapies may be sought.

Staged gamma knife radiosurgery for large cerebral arteriovenous malformations.

BACKGROUND: We present our experience over a 10-year period of staged radiosurgery for large arteriovenous malformations (AVMs) including patient outcomes and methods. METHODS: From July 2000 to December 2010, 80 patients with AVMs were treated with gamma knife radiosurgery (GKS) at our institution; of these patients, 5 were treated for large AVMs with staged GKS (volumes >20 cm(3)). The mean interval between treatments was 10 months (range 7-16). The mean dose for the margin used was 18.0 Gy (range 16-20). The mean volume treated was 37.2 cm(3) (range 22-50). The mean total follow-up was 76.5 months (range 42-120). RESULTS: Two patients had complete obliteration of the AVM nidus. One patient had 95% obliteration (31 months after radiosurgery), one had 90% obliteration (38 months after radiosurgery), and one had less than 50% obliteration at 53 months with a 16-month interval between staged treatments. CONCLUSIONS: Staged radiosurgery is an effective and safe method for the treatment of large AVMs. We report achieving higher marginal doses with staging in planned intervals of 6-9 months between staged treatments. It appears that the longer the wait between treatments, the less likely it is that complete obliteration will be achieved.

Hepato-biliary late effects in survivors of childhood and adolescent cancer: a report from the Children's Oncology Group.

Curative therapy for childhood and adolescent cancer translates to 1 in 640 young adults being a survivor of cancer. Although acute hepato-biliary toxicity occurs commonly during pediatric cancer therapy, the impact of antineoplastic therapy on long-term liver health in childhood/adolescent cancer survivors is unknown. This article reviews the medical literature on late liver dysfunction following treatment for childhood/adolescent cancer. We also outline the Children's Oncology Group (COG) guidelines for screening and follow-up of hepato-biliary sequelae. As the population of survivors grow and age, vigilance for risks to hepatic health needs to continue based on specific exposures during curative cancer therapy.

Conformal Radiation Therapy for Pediatric Patients with Low-Grade Glioma: Results from the Children's Oncology Group Phase 2 Study ACNS0221.

PURPOSE: To determine the rate of marginal relapse, progression-free survival (PFS), and overall survival (OS) in patients with pediatric low-grade glioma (PLGG) treated with conformal radiation therapy (CRT) with a clinical target volume (CTV) margin of 5 mm in the Children's Oncology Group trial ACNS0221. METHODS AND MATERIALS: Patients aged 3 to 21 years with unresectable progressive, recurrent, or residual PLGG were eligible for this study. Patients younger than 10 years were required to have received at least 1 chemotherapy course. Patients with neurofibromatosis type I were not eligible. All patients underwent magnetic resonance imaging-based planning and received 54 Gy CRT in 30 fractions with a 5-mm CTV margin. RESULTS: Of 85 eligible patients (median age, 13.6 years) treated between March 2006 and December 2010, 14 were younger than 10 years and 36 received prior chemotherapy. Sixty-six had pilocytic astrocytoma, 15 had other histologic subtypes, and 4 had unbiopsied chiasmatic lesions. Events included 23 relapses (19 central, 4 distant, and no marginal) and 7 deaths. At a median follow-up of 5.15 years, 5-year PFS was 71% ± 6% and OS was 93% ± 4%. Male sex (P = .068) and large tumor size (P = .050) trended toward significance for association with decreased PFS. Age, histology, tumor location, time between diagnosis and study entry, and MIB-1 status were not associated with PFS. OS was negatively associated with male sex (P = .064), non-pilocytic astrocytoma histology (P = .010), and large tumor size (P = .0089). CONCLUSIONS: For patients with PLGG, CRT with a CTV margin of 5 mm yields an acceptable PFS and does not lead to a high rate of marginal relapse.