Therapeutic Impact of Cytoreductive Surgery and Irradiation of Posterior Fossa Ependymoma in the Molecular Era: A Retrospective Multicohort Analysis.

PURPOSE: Posterior fossa ependymoma comprises two distinct molecular variants termed EPN_PFA and EPN_PFB that have a distinct biology and natural history. The therapeutic value of cytoreductive surgery and radiation therapy for posterior fossa ependymoma after accounting for molecular subgroup is not known. METHODS: Four independent nonoverlapping retrospective cohorts of posterior fossa ependymomas (n = 820) were profiled using genome-wide methylation arrays. Risk stratification models were designed based on known clinical and newly described molecular biomarkers identified by multivariable Cox proportional hazards analyses. RESULTS: Molecular subgroup is a powerful independent predictor of outcome even when accounting for age or treatment regimen. Incompletely resected EPN_PFA ependymomas have a dismal prognosis, with a 5-year progression-free survival ranging from 26.1% to 56.8% across all four cohorts. Although first-line (adjuvant) radiation is clearly beneficial for completely resected EPN_PFA, a substantial proportion of patients with EPN_PFB can be cured with surgery alone, and patients with relapsed EPN_PFB can often be treated successfully with delayed external-beam irradiation. CONCLUSION: The most impactful biomarker for posterior fossa ependymoma is molecular subgroup affiliation, independent of other demographic or treatment variables. However, both EPN_PFA and EPN_PFB still benefit from increased extent of resection, with the survival rates being particularly poor for subtotally resected EPN_PFA, even with adjuvant radiation therapy. Patients with EPN_PFB who undergo gross total resection are at lower risk for relapse and should be considered for inclusion in a randomized clinical trial of observation alone with radiation reserved for those who experience recurrence.

A Phase I Study of Tomotherapy in Patients With Primary Benign and Low-grade Brain Tumors: Late Toxicity and Quality of Life.

OBJECTIVES: To evaluate longitudinal quality of life and late neurotoxicity (>12 mo) of tomotherapy in patients with primary benign and low-grade brain tumors. METHODS: Between January 2006 and October 2009, 49 patients with brain tumors were treated with tomotherapy at 2 radiotherapy centers in Canada. The median age of the patients was 51.0 years (range, 21 to 74 y); there were 21 men (42.86%) and 28 women (57.14%). All 49 patients had an initial Karnofsky performance score ≥70. One patient (2.04%) received 45 Gy in 25 fractions, 27 patients (55.10%) received 50.4 Gy in 28 fractions, 15 patients (30.6%) received 54 Gy in 30 fractions, and 5 patients (10.2%) received 60 Gy in 30 fractions. A total of 47 patients were analyzed for late toxicity and outcomes. RESULTS: Changes in the Karnofsky Performance Status of the patients did not reach statistical significance (P>0.05). The majority of the quality of life parameters that reached a statistically significant level (P<0.05) of change at 2 years were changes toward improvement (drowsiness, itchy skin, emotional functioning, fatigue, nausea, and appetite). Statistically significant (P<0.05) interval deterioration in physical, role, and social functioning was observed. Actuarial overall survival at 5 years was 91.6%; disease-free survival at 5 years was 86.6%. CONCLUSIONS: IMRT helical tomotherapy is well tolerated, without statistically significant constitutional and late neurotoxicity up to the 2-year mark.

Phase I study of hypofractionated intensity modulated radiation therapy with concurrent and adjuvant temozolomide in patients with glioblastoma multiforme.

PURPOSE: To determine the safety and efficacy of hypofractionated intensity modulated radiation therapy (Hypo-IMRT) using helical tomotherapy (HT) with concurrent low dose temozolomide (TMZ) followed by adjuvant TMZ in patients with glioblastoma multiforme (GBM). METHODS AND MATERIALS: Adult patients with GBM and KPS > 70 were prospectively enrolled between 2005 and 2007 in this phase I study. The Fibonacci dose escalation protocol was implemented to establish a safe radiation fractionation regimen. The protocol defined radiation therapy (RT) dose level I as 54.4 Gy in 20 fractions over 4 weeks and dose level II as 60 Gy in 22 fractions over 4.5 weeks. Concurrent TMZ followed by adjuvant TMZ was given according to the Stupp regimen. The primary endpoints were feasibility and safety of Hypo-IMRT with concurrent TMZ. Secondary endpoints included progression free survival (PFS), pattern of failure, overall survival (OS) and incidence of pseudoprogression. The latter was defined as clinical or radiological suggestion of tumour progression within three months of radiation completion followed by spontaneous recovery of the patient. RESULTS: A total of 25 patients were prospectively enrolled with a median follow-up of 12.4 months. The median age at diagnosis was 53 years. Based on recursive partitioning analysis (RPA) criteria, 16%, 52% and 32% of the patients were RPA class III, class IV and class V, respectively. All patients completed concurrent RT and TMZ, and 19 patients (76.0%) received adjuvant TMZ. The median OS was 15.67 months (95% CI 11.56 - 20.04) and the median PFS was 6.7 months (95% CI 4.0 - 14.0). The median time between surgery and start of RT was 44 days (range of 28 to 77 days). Delaying radiation therapy by more than 6 weeks after surgery was an independent prognostic factor associated with a worse OS (4.0 vs. 16.1 months, P = 0.027). All recurrences occurred within 2 cm of the original gross tumour volume (GTV). No cases of pseudoprogression were identified in our cohort of patients. Three patients tolerated dose level I with no dose limiting toxicity and hence the remainder of the patients were treated with dose level II according to the dose escalation protocol. Grade 3-4 hematological toxicity was limited to two patients and one patient developed Grade 4 Pneumocystis jiroveci pneumonia. CONCLUSION: Hypo-IMRT using HT given with concurrent TMZ is feasible and safe. The median OS and PFS are comparable to those observed with conventional fractionation. Hypofractionated radiation therapy offers the advantage of a shorter treatment period which is imperative in this group of patients with limited life expectancy.

Changes in serial magnetic resonance spectroscopy predict outcome in high-grade glioma during and after postoperative radiotherapy.

AIM: To determine any correlation between magnetic resonance spectroscopy (MRS) pattern of high-grade glioma before, during, and after radiotherapy (RT) with overall survival (OS) and progression-free survival (PFS). PATIENTS AND METHODS: Twenty-six patients prospectively underwent surgery and RT to 60 Gy. MRS was performed before RT, at week 4 of RT, and 2 months post-RT. Normalized and relative metabolite ratios were evaluated. Patients were grouped according to similar evolving MRS patterns and analyzed for differences in OS and PFS. RESULTS: Significant decreases in tumor choline/N-acetyl-aspartate and normalized choline were observed from baseline to post-RT. After a median follow-up of 22.9 months, patients with >40% decrease in normalized choline from week 4 during RT to 2 months post-RT had a significantly worse median OS (9.1 months vs. not reached, p<0.00001) and PFS (5.8 vs. 19.8 months, p=0.0018). CONCLUSION: The change in normalized choline at 2 months post-RT was highly prognostic for PFS and OS. This may allow more individualized response-based treatment.

Phase II trial of continuous dose-intense temozolomide in recurrent malignant glioma: RESCUE study.

PURPOSE Concomitant temozolomide (TMZ)/radiotherapy followed by adjuvant TMZ has increased survival in patients with glioblastoma multiforme (GBM). However, few options are effective for patients who experience treatment failure. We conducted a multicenter, phase II study to assess the efficacy and safety of continuous dose-intense TMZ for recurrent GBM. PATIENTS AND METHODS Patients with malignant glioma at progression after standard TMZ 150 to 200 mg/m(2) x 5 days in a 28-day cycle for three or more cycles were stratified by tumor type (anaplastic glioma group A, GBM, group B). Ninety-one patients with GBM were prospectively divided into three groups (early [B1], extended [B2], and rechallenge [B3]) according to the timing of progression during adjuvant therapy. All patients received continuous dose-intense TMZ 50 mg/m(2)/d for up to 1 year or until progression occurred. Response was assessed by using RECIST (Response Evaluation Criteria in Solid Tumors). Results A total of 116 of 120 patients were evaluable for efficacy. For patients with GBM, 6-month progression-free survival (PFS) was 23.9% (B1, 27.3%; B2, 7.4%; B3, 35.7%). One-year survival from time of study entry was 27.3%, 14.8%, and 28.6% for the B1, B2 and B3 groups, respectively. For patients with anaplastic glioma, 6-month PFS was 35.7%; 1-year survival was 60.7%. The most common grades 3 and 4 nonhematologic toxicities were nausea/vomiting (6.7%) and fatigue (5.8%). Grades 3 and 4 hematologic toxicities were uncommon. CONCLUSION Rechallenge with continuous dose-intense TMZ 50 mg/m(2)/d is a valuable therapeutic option for patients with recurrent GBM. Patients who experience progression during the first six cycles of conventional adjuvant TMZ therapy or after a treatment-free interval get the most benefit from therapy.

X-linked inhibitor regulating TRAIL-induced apoptosis in chemoresistant human primary glioblastoma cells.

INTRODUCTION: The X-chromosome-linked inhibitor of apoptosis protein (XIAP) prevents apoptosis from activated transmembrane death receptors and confers tumour resistance to irradiation and chemotherapy. Despite the important oncologic implications, data concerning glioblastoma in this regard are few and isolated. The objective of this study was to examine the role of XIAP in the signalling pathway of TRAIL (tumour necrosis factor-related apoptosis-inducing ligand)-mediated apoptosis in chemoresistant human glioblastoma cells. METHOD: Downregulators of XIAP, low-dose cisplatin, etoposide (VP 16) or second mitochondria-derived activator of caspase (Smac)-Tat peptide, were applied to 2 chemoresistant glioblastoma cell lines of fresh isolates to identify the impact of these sensitizing agents on the cytotoxicity of TRAIL. Hoechst staining for apoptotic nuclear morphology and Western blot analysis for the corresponding levels of proteins that regulate apoptotic pathways including XIAP were performed. The involvement of mitochondrial pathways marked by the release of cytochrome c or Smac/direct IAP (inhibitor of apoptosis protein)-binding protein with low P1 (DIABLO), or both, was assessed by confocal fluorescence microscopy. RESULTS: Downregulators of XIAP induced apoptosis in a dose-dependent manner with TRAIL in 1 chemoresistant glioblastoma cell line. Here, XIAP downregulation modulated by Smac-Tat peptide resulted in increased TRAIL-induced cell death. In addition, TRAIL was shown to enhance the translocation of Smac/DIABLO from mitochondria to the cytosol in cells that underwent apoptosis, which in turn neutralized XIAP activity. In comparison, the second chemoresistant glioblastoma cell line showed no regulatory XIAP effect. This finding correlates with the upstream effect of mutant p53 and BCL-X(L) status that were upregulated in this chemoresistant cell line. CONCLUSION: These results support the use of selective or tailored therapeutic strategies that synergistically sensitize chemoresistant glioblastoma to TRAIL-mediated apoptosis by administering appropriate XIAP downregulating agents.

Prophylactic anticonvulsants in patients with brain tumour.

OBJECTIVE: We conducted a clinical trial to determine if prophylactic anticonvulsants in brain tumour patients (without prior seizures) reduced seizure frequency. We stopped accrual at 100 patients on the basis of the interim analysis. METHODS: One hundred newly diagnosed brain tumour patients received anticonvulsants (AC Group) or not (No AC Group) in this prospective randomized unblinded study. Sixty patients had metastatic, and 40 had primary brain tumours. Forty-six (46%) patients were randomized to the AC Group and 54 (54%) to the No AC Group. Median follow-up was 5.44 months (range 0.13-30.1 months). RESULTS: Seizures occurred in 26 (26%) patients, eleven in the AC Group and 15 in the No AC Group. Seizure-free survivals were not different; at three months 87% of the AC Group and 90% of the No AC Group were seizure-free (log rank test, p = 0.98). Seventy patients died (unrelated to seizures) and survival rates were equivalent in both groups (median survival = 6.8 months versus 5.6 months, respectively; log rank test, p = 0.50). We then terminated accrual at 100 patients because seizure and survival rates were much lower than expected; we would need > or = 900 patients to have a suitably powered study. CONCLUSIONS: These data should be used by individuals contemplating a clinical trial to determine if prophylactic anticonvulsants are effective in subsets of brain tumour patients (e.g. only anaplastic astrocytomas). When taken together with the results of a similar randomized trial, prophylactic anticonvulsants are unlikely to be effective or useful in brain tumour patients who have not had a seizure.

An open label trial of sustained-release cytarabine (DepoCyt) for the intrathecal treatment of solid tumor neoplastic meningitis.

Drugs currently available for intrathecal administration are cleared rapidly from the CSF. DepoCyt is a slow-release formulation of cytarabine that maintains cytotoxic concentrations of free cytarabine in the CSF for >14 days following a single injection. DepoCyt was administered to 110 patients with a diagnosis of neoplastic meningitis based on either a positive CSF cytology (76) or neurologic and CT or MRI scan findings sufficient to document neoplastic meningitis (34). Patients were treated with DepoCyt 50mg every 2 weeks for 1 month of induction therapy by either lumbar puncture (LP) or intraventricular (IVT) injection. Patients without neurologic progression were candidates to receive an additional 3 months of consolidation therapy. All patients received dexamethasone 4 mg BID on days 1-5 of each cycle. Median time to neurologic progression was 55 days; median overall survival was 95 days. Among the 76 patients with a positive CSF cytology at baseline, 70 were evaluable for response, and of this group 19 (27%) attained the criteria for response (cytologic response in the absence of neurologic progression). The most important adverse events were headache and arachnoiditis. When drug-related, these were largely low grade, transient, and reversible. Drug-related grade 3 headache occurred on 4% of cycles; grade 3 or 4 arachnoiditis occurred on 6% of cycles. No cumulative toxicity was observed. DepoCyt injected once every 2 weeks produced a response-rate comparable to that previously reported for methotrexate given twice a week. The once in every 2-week-dosing interval offers an advantage over conventional schedules (2-3 doses/week) used for other agents available for intrathecal injection.