Updated response assessment criteria for high-grade gliomas: response assessment in neuro-oncology working group

Currently, the most widely used criteria for assessing response to therapy in high-grade gliomas are based on two-dimensional tumor measurements on computed tomography (CT) or magnetic resonance imaging (MRI), in conjunction with clinical assessment and corticosteroid dose (the Macdonald Criteria). It is increasingly apparent that there are significant limitations to these criteria, which only address the contrast-enhancing component of the tumor. For example, chemoradiotherapy for newly diagnosed glioblastomas results in transient increase in tumor enhancement (pseudoprogression) in 20% to 30% of patients, which is difficult to differentiate from true tumor progression. Antiangiogenic agents produce high radiographic response rates, as defined by a rapid decrease in contrast enhancement on CT/MRI that occurs within days of initiation of treatment and that is partly a result of reduced vascular permeability to contrast agents rather than a true antitumor effect. In addition, a subset of patients treated with antiangiogenic agents develop tumor recurrence characterized by an increase in the nonenhancing component depicted on T2-weighted/fluid-attenuated inversion recovery sequences. The recognition that contrast enhancement is nonspecific and may not always be a true surrogate of tumor response and the need to account for the nonenhancing component of the tumor mandate that new criteria be developed and validated to permit accurate assessment of the efficacy of novel therapies. The Response Assessment in Neuro-Oncology Working Group is an international effort to develop new standardized response criteria for clinical trials in brain tumors. In this proposal, we present the recommendations for updated response criteria for high-grade gliomas.

Glioblastoma in adults: a Society for Neuro-Oncology (SNO) and European Society of Neuro-Oncology (EANO) consensus review on current management and future directions

Glioblastomas are the most common form of malignant primary brain tumor and an important cause of morbidity and mortality. In recent years there have been important advances in understanding the molecular pathogenesis and biology of these tumors, but this has not translated into significantly improved outcomes for patients. In this consensus review from the Society for Neuro-Oncology (SNO) and the European Association of Neuro-Oncology (EANO), the current management of isocitrate dehydrogenase wildtype (IDHwt) glioblastomas will be discussed. In addition, novel therapies such as targeted molecular therapies, agents targeting DNA damage response and metabolism, immunotherapies, and viral therapies will be reviewed, as well as the current challenges and future directions for research.

Treatment for Brain Metastases: ASCO-SNO-ASTRO Guideline

PURPOSE

To provide guidance to clinicians regarding therapy for patients with brain metastases from solid tumors.

METHODS

ASCO convened an Expert Panel and conducted a systematic review of the literature.

RESULTS

Thirty-two randomized trials published in 2008 or later met eligibility criteria and form the primary evidentiary base.

RECOMMENDATIONS

Surgery is a reasonable option for patients with brain metastases. Patients with large tumors with mass effect are more likely to benefit than those with multiple brain metastases and/or uncontrolled systemic disease. Patients with symptomatic brain metastases should receive local therapy regardless of the systemic therapy used. For patients with asymptomatic brain metastases, local therapy should not be deferred unless deferral is specifically recommended in this guideline. The decision to defer local therapy should be based on a multidisciplinary discussion of the potential benefits and harms that the patient may experience. Several regimens were recommended for non-small-cell lung cancer, breast cancer, and melanoma. For patients with asymptomatic brain metastases and no systemic therapy options, stereotactic radiosurgery (SRS) alone should be offered to patients with one to four unresected brain metastases, excluding small-cell lung carcinoma. SRS alone to the surgical cavity should be offered to patients with one to two resected brain metastases. SRS, whole brain radiation therapy, or their combination are reasonable options for other patients. Memantine and hippocampal avoidance should be offered to patients who receive whole brain radiation therapy and have no hippocampal lesions and 4 months or more expected survival. Patients with asymptomatic brain metastases with either Karnofsky Performance Status ≤ 50 or Karnofsky Performance Status < 70 with no systemic therapy options do not derive benefit from radiation therapy.Additional information is available at www.asco.org/neurooncology-guidelines.

"Pulsatile" high-dose weekly erlotinib for CNS metastases from EGFR mutant non-small cell lung cancer

Erlotinib is effective for epidermal growth factor receptor (EGFR) mutant lung cancer, but CNS penetration at standard daily dosing is limited. We previously reported that intermittent "pulsatile" administration of high-dose (1500 mg) erlotinib once weekly was tolerable and achieved concentrations in cerebrospinal fluid exceeding the half maximal inhibitory concentration for EGFR mutant lung cancer cells in a patient with leptomeningeal metastases; we now expand this paradigm to a series of 9 patients. We retrospectively identified patients with EGFR mutant lung cancer treated with pulsatile erlotinib for CNS metastases (brain and/or leptomeningeal) that occurred despite conventional daily erlotinib or other EGFR tyrosine kinase inhibitors. Mutations in available lung and CNS tissue were correlated with efficacy. Erlotinib was administered as monotherapy at a median dose of 1500 mg weekly. Best CNS radiographic response was partial in 67% (6/9, including 2 with isolated leptomeningeal metastases), stable disease in 11% (1/9), and progressive disease in 22% (2/9). Median time to CNS progression was 2.7 months (range, 0.8-14.5 months) and median overall survival was 12 months (range, 2.5 months-not reached). Treatment was well tolerated. No acquired resistance mutations in EGFR were identified in the CNS metastases of 4 patients, including 1 harboring T790M outside the CNS. Pulsatile erlotinib can control CNS metastases from EGFR mutant lung cancer after failure of standard daily dosing. CNS disease may not harbor acquired resistance mutations that develop systemically. A prospective trial is planned.

Differential sensitivity of glioma- versus lung cancer-specific EGFR mutations to EGFR kinase inhibitors

Activation of the epidermal growth factor receptor (EGFR) in glioblastoma (GBM) occurs through mutations or deletions in the extracellular (EC) domain. Unlike lung cancers with EGFR kinase domain (KD) mutations, GBMs respond poorly to the EGFR inhibitor erlotinib. Using RNAi, we show that GBM cells carrying EGFR EC mutations display EGFR addiction. In contrast to KD mutants found in lung cancer, glioma-specific EGFR EC mutants are poorly inhibited by EGFR inhibitors that target the active kinase conformation (e.g., erlotinib). Inhibitors that bind to the inactive EGFR conformation, however, potently inhibit EGFR EC mutants and induce cell death in EGFR-mutant GBM cells. Our results provide first evidence for single kinase addiction in GBM and suggest that the disappointing clinical activity of first-generation EGFR inhibitors in GBM versus lung cancer may be attributed to the different conformational requirements of mutant EGFR in these 2 cancer types.

SIGNIFICANCE

Approximately 40% of human glioblastomas harbor oncogenic EGFR alterations, but attempts to therapeutically target EGFR with first-generation EGFR kinase inhibitors have failed. Here, we demonstrate selective sensitivity of glioma-specific EGFR mutants to ATP-site competitive EGFR kinase inhibitors that target the inactive conformation of the catalytic domain.

Patterns of relapse and prognosis after bevacizumab failure in recurrent glioblastoma

BACKGROUND

Bevacizumab has recently been approved by the US Food and Drug Administration for recurrent glioblastoma (GBM). However, patterns of relapse, prognosis, and outcome of further therapy after bevacizumab failure have not been studied systematically.

METHODS

We identified patients at Memorial Sloan-Kettering Cancer Center with recurrent GBM who discontinued bevacizumab because of progressive disease.

RESULTS

There were 37 patients (26 men with a median age of 54 years). The most common therapies administered concurrently with bevacizumab were irinotecan (43%) and hypofractionated reirradiation (38%). The median overall survival (OS) after progressive disease on bevacizumab was 4.5 months; 34 patients died. At the time bevacizumab was discontinued for tumor progression, 17 patients (46%) had an increase in the size of enhancement at the initial site of disease (local recurrence), 6 (16%) had a new enhancing lesion outside of the initial site of disease (multifocal), and 13 (35%) had progression of predominantly nonenhancing tumor. Factors associated with shorter OS after discontinuing bevacizumab were lower performance status and nonenhancing pattern of recurrence. Additional salvage chemotherapy after bevacizumab failure was given to 19 patients. The median progression-free survival (PFS) among these 19 patients was 2 months, the median OS was 5.2 months, and the 6-month PFS rate was 0%.

CONCLUSIONS

Contrast enhanced MRI does not adequately assess disease status during bevacizumab therapy for recurrent glioblastoma (GBM). A nonenhancing tumor pattern of progression is common after treatment with bevacizumab for GBM and is correlated with worse survival. Treatments after bevacizumab failure provide only transient tumor control.

A phase II trial of erlotinib in patients with recurrent malignant gliomas and nonprogressive glioblastoma multiforme postradiation therapy

Patients with (a) recurrent malignant glioma (MG): glioblastoma (GBM) or recurrent anaplastic glioma (AG), and (b) nonprogressive (NP) GBM following radiation therapy (RT) were eligible. Primary objective for recurrent MG was progression-free survival at 6 months (PFS-6) and overall survival at 12 months for NP GBM post-RT. Secondary objectives for recurrent MGs were response, survival, assessment of toxicity, and pharmacokinetics (PKs). Treatment with enzyme-inducing antiepileptic drugs was not allowed. Patients received 150 mg/day erlotinib. Patients requiring surgery were treated 7 days prior to tumor removal for PK analysis and effects of erlotinib on epidermal growth factor receptor (EGFR) and intracellular signaling pathways. Ninety-six patients were evaluable (53 recurrent MG and 43 NP GBM); 5 patients were not evaluable for response. PFS-6 in recurrent GBM was 3% with a median PFS of 2 months; PFS-6 in recurrent AG was 27% with a median PFS of 2 months. Twelve-month survival was 57% in NP GBMs post-RT. Primary toxicity was dermatologic. The tissue-to-plasma ratio normalized to nanograms per gram dry weight for erlotinib and OSI-420 ranged from 25% to 44% and 30% to 59%, respectively, for pretreated surgical patients. No effect on EGFR or intratumoral signaling was seen. Patients with NP GBM post-RT who developed rash in cycle 1 had improved survival (P < .001). Single-agent activity of erlotinib is minimal for recurrent MGs and marginally beneficial following RT for NP GBM patients. Development of rash in cycle 1 correlates with survival in patients with NP GBM after RT.

Molecular study of malignant gliomas treated with epidermal growth factor receptor inhibitors: tissue analysis from North American Brain Tumor Consortium Trials 01-03 and 00-01

PURPOSE

We investigated the molecular effect of the epidermal growth factor receptor (EGFR) inhibitors erlotinib and gefitinib in vivo on all available tumors from patients treated on North American Brain Tumor Consortium trials 01-03 and 00-01 for recurrent or progressive malignant glioma.

EXPERIMENTAL DESIGN

EGFR expression and signaling during treatment with erlotinib or gefitinib were analyzed by Western blot and compared with pre-erlotinib/gefitinib-exposed tissue or unexposed controls. Tumors were also analyzed for EGFR mutations and for other genomic abnormalities by array-based comparative genomic hybridization. Clinical data were used to associate molecular features with tumor sensitivity to erlotinib or gefitinib.

RESULTS

Erlotinib and gefitinib did not markedly affect EGFR activity in vivo. No lung signature mutations of EGFR exons 18 to 21 were observed. There was no clear association between erlotinib/gefitinib sensitivity and deletion or amplification events on array-based comparative genomic hybridization analysis, although novel genomic changes were identified.

CONCLUSIONS

As erlotinib and gefitinib were generally ineffective at markedly inhibiting EGFR phosphorylation in these tumors, other assays may be needed to detect molecular effects. Additionally, the mechanism of erlotinib/gefitinib sensitivity likely differs between brain and lung tumors. Finally, novel genomic changes, including deletions of chromosomes 6, 21, and 22, represent new targets for further research.

Phase II trial of sunitinib for recurrent and progressive atypical and anaplastic meningioma

BACKGROUND

No proven effective medical therapy for surgery and radiation-refractory meningiomas exists. Sunitinib malate (SU011248) is a small-molecule tyrosine kinase inhibitor that targets vascular endothelial growth factor receptor (VEGFR) and platelet-derived growth factor receptor, abundant in meningiomas.

METHODS

This was a prospective, multicenter, investigator-initiated single-arm phase II trial. The primary cohort enrolled patients with surgery and radiation-refractory recurrent World Health Organization (WHO) grades II-III meningioma. An exploratory cohort enrolled patients with WHO grade I meningioma, hemangiopericytoma, or hemangioblastoma. Sunitinib was administered at 50 mg/d for days 1-28 of every 42-day cycle. The primary endpoint was the rate of 6-month progression-free survival (PFS6), with secondary endpoints of radiographic response rate, safety, PFS, and overall survival. Exploratory objectives include analysis of tumoral molecular markers and MR perfusion imaging.

RESULTS

Thirty-six patients with high-grade meningioma (30 atypical and 6 anaplastic) were enrolled. Patients were heavily pretreated (median number of 5 recurrences, range 2-10). PFS6 rate was 42%, meeting the primary endpoint. Median PFS was 5.2 months (95% CI: 2.8-8.3 mo), and median overall survival was 24.6 months (95% CI: 16.5-38.4 mo). Thirteen patients enrolled in the exploratory cohort. Overall toxicity included 1 grade 5 intratumoral hemorrhage, 2 grade 3 and 1 grade 4 CNS/intratumoral hemorrhages, 1 grade 3 and 1 grade 4 thrombotic microangiopathy, and 1 grade 3 gastrointestinal perforation. Expression of VEGFR2 predicted PFS of a median of 1.4 months in VEGFR2-negative patients versus 6.4 months in VEGFR2-positive patients (P = .005).

CONCLUSION

Sunitinib is active in recurrent atypical/malignant meningioma patients. A randomized trial should be performed.

Brain metastases

Brain metastases are one of the most feared complications of cancer because even small tumors may cause incapacitating neurologic symptoms. This article reviews the epidemiology, clinical features, treatment, and prognosis of brain metastases from system malignancies.

Phase II study of aflibercept in recurrent malignant glioma: a North American Brain Tumor Consortium study

PURPOSE

Antivascular endothelial growth factor (anti-VEGF) therapy is a promising treatment approach for patients with recurrent glioblastoma. This single-arm phase II study evaluated the efficacy of aflibercept (VEGF Trap), a recombinantly produced fusion protein that scavenges both VEGF and placental growth factor in patients with recurrent malignant glioma.

PATIENTS AND METHODS

Forty-two patients with glioblastoma and 16 patients with anaplastic glioma who had received concurrent radiation and temozolomide and adjuvant temozolomide were enrolled at first relapse. Aflibercept 4 mg/kg was administered intravenously on day 1 of every 2-week cycle.

RESULTS

The 6-month progression-free survival rate was 7.7% for the glioblastoma cohort and 25% for patients with anaplastic glioma. Overall radiographic response rate was 24% (18% for glioblastoma and 44% for anaplastic glioma). The median progression-free survival was 24 weeks for patients with anaplastic glioma (95% CI, 5 to 31 weeks) and 12 weeks for patients with glioblastoma (95% CI, 8 to 16 weeks). A total of 14 patients (25%) were removed from the study for toxicity, on average less than 2 months from treatment initiation. The main treatment-related National Cancer Institute Common Terminology Criteria grades 3 and 4 adverse events (38 total) included fatigue, hypertension, and lymphopenia. Two grade 4 CNS ischemias and one grade 4 systemic hemorrhage were reported. Aflibercept rapidly decreases permeability on dynamic contrast enhanced magnetic resonance imaging, and molecular analysis of baseline tumor tissue identified tumor-associated markers of response and resistance.

CONCLUSION

Aflibercept monotherapy has moderate toxicity and minimal evidence of single-agent activity in unselected patients with recurrent malignant glioma.

Phase II trials of erlotinib or gefitinib in patients with recurrent meningioma

There are no established treatments for recurrent meningioma when surgical and radiation options are exhausted. The epidermal growth factor receptor (EGFR) is often over-expressed in meningiomas and may promote tumor growth. In open label, single arm phase II studies of the EGFR inhibitors gefitinib (NABTC 00-01) and erlotinib (NABTC 01-03) for recurrent malignant gliomas, we included exploratory subsets of recurrent meningioma patients. We have pooled the data and report the results here. Patients with recurrent histologically confirmed meningiomas with no more than 2 previous chemotherapy regimens were treated with gefitinib 500 mg/day or erlotinib 150 mg/day until tumor progression or unacceptable toxicity. Twenty-five eligible patients were enrolled with median age 57 years (range 29-81) and median Karnofsky performance status (KPS) score 90 (range 60-100). Sixteen patients (64%) received gefitinib and 9 (36%) erlotinib. Eight patients (32%) had benign tumors, 9 (36%) atypical, and 8 (32%) malignant. For benign tumors, the 6-month progression-free survival (PFS6) was 25%, 12-month PFS (PFS12) 13%, 6-month overall survival (OS6) 63%, and 12-month OS (OS12) 50%. For atypical and malignant tumors, PFS6 was 29%, PFS12 18%, OS6 71%, and OS12 65%. The PFS and OS were not significantly different by histology. There were no objective imaging responses, but 8 patients (32%) maintained stable disease. Although treatment was well-tolerated, neither gefitinib nor erlotinib appear to have significant activity against recurrent meningioma. The role of EGFR inhibitors in meningiomas is unclear. Evaluation of multi-targeted inhibitors and EGFR inhibitors in combination with other targeted molecular agents may be warranted.

RANO 2.0: Update to the Response Assessment in Neuro-Oncology Criteria for High- and Low-Grade Gliomas in Adults

PURPOSE

The Response Assessment in Neuro-Oncology (RANO) criteria for high-grade gliomas (RANO-HGG) and low-grade gliomas (RANO-LGG) were developed to improve reliability of response assessment in glioma trials. Over time, some limitations of these criteria were identified, and challenges emerged regarding integrating features of the modified RANO (mRANO) or the immunotherapy RANO (iRANO) criteria.

METHODS

Informed by data from studies evaluating the different criteria, updates to the RANO criteria are proposed (RANO 2.0).

RESULTS

We recommend a standard set of criteria for both high- and low-grade gliomas, to be used for all trials regardless of the treatment modalities being evaluated. In the newly diagnosed setting, the postradiotherapy magnetic resonance imaging (MRI), rather than the postsurgical MRI, will be used as the baseline for comparison with subsequent scans. Since the incidence of pseudoprogression is high in the 12 weeks after radiotherapy, continuation of treatment and confirmation of progression during this period with a repeat MRI, or histopathologic evidence of unequivocal recurrent tumor, are required to define tumor progression. However, confirmation scans are not mandatory after this period nor for the evaluation of treatment for recurrent tumors. For treatments with a high likelihood of pseudoprogression, mandatory confirmation of progression with a repeat MRI is highly recommended. The primary measurement remains the maximum cross-sectional area of tumor (two-dimensional) but volumetric measurements are an option. For IDH wild-type glioblastoma, the nonenhancing disease will no longer be evaluated except when assessing response to antiangiogenic agents. In IDH-mutated tumors with a significant nonenhancing component, clinical trials may require evaluating both the enhancing and nonenhancing tumor components for response assessment.

CONCLUSION

The revised RANO 2.0 criteria refine response assessment in gliomas.

International retrospective study of over 1000 adults with anaplastic oligodendroglial tumors

Treatment for newly diagnosed anaplastic oligodendroglial tumors is controversial. Radiotherapy (RT) alone and in combination with chemotherapy (CT) are the most well studied strategies. However, CT alone is often advocated, especially in cases with 1p19q codeletion. We retrospectively identified 1013 adults diagnosed from 1981-2007 treated initially with RT alone (n = 200), CT + RT (n = 528), CT alone (n = 201), or other strategies (n = 84). Median overall survival (OS) was 6.3 years and time to progression (TTP) was 3.1 years. 1p19q codeletion correlated with longer OS and TTP than no 1p or 19q deletion. In codeleted cases, median TTP was longer following CT + RT (7.2 y) than following CT (3.9 y, P = .003) or RT (2.5 y, P < .001) alone but without improved OS; median TTP was longer following treatment with PCV alone than temozolomide alone (7.6 vs. 3.3 y, P = .019). In cases with no deletion, median TTP was longer following CT + RT (3.1 y) than CT (0.9 y, P = .0124) or RT (1.1 y, P < .0001) alone; OS also favored CT + RT (median 5.0 y) over CT (2.2 y, P = .02) or RT (1.9 y, P < .0001) alone. In codeleted cases, CT alone did not appear to shorten OS in comparison with CT + RT, and PCV appeared to offer longer disease control than temozolomide but without a clear survival advantage. Combined CT + RT led to longer disease control and survival than did CT or RT alone in cases with no 1p19q deletion. Ongoing trials will address these issues prospectively.

Randomized phase II trial of chemoradiotherapy followed by either dose-dense or metronomic temozolomide for newly diagnosed glioblastoma

PURPOSE

Alternative dosing schedules of temozolomide may improve survival in patients with newly diagnosed glioblastoma (GBM) by increasing the therapeutic index, overcoming common mechanisms of temozolomide resistance, or both. The goal of this randomized phase II study was to evaluate two different temozolomide regimens in the adjuvant treatment of newly diagnosed GBM.

PATIENTS AND METHODS

Adult patients with newly diagnosed GBM were randomly assigned to receive standard radiotherapy with concurrent daily temozolomide followed by six adjuvant cycles of either dose-dense (150 mg/m(2) days 1 to 7 and 15 to 21) or metronomic (50 mg/m(2) continuous daily) temozolomide. Maintenance doses of 13-cis-retinoic acid were then administered until tumor progression. The primary end point was overall survival (OS) at 1 year. Tumor tissue was assayed to determine O(6)-methylguanine-DNA methyltransferase (MGMT) promoter methylation status.

RESULTS

Eighty-five eligible patients were enrolled; 42 were randomly assigned to dose-dense and 43 to metronomic temozolomide. The 1-year survival rate was 80% for the dose-dense arm and 69% for the metronomic arm; median OS was 17.1 months (95% CI, 14.0 to 28.1 months) and 15.1 months (95% CI, 12.3 to 18.9 months), respectively. The most common toxicities were myelosuppression (leukopenia, neutropenia, and thrombocytopenia) and elevated liver enzymes. Pseudoprogression was observed in 37% of assessable patients and may have had an impact on estimates of progression-free survival (6.6 months in the dose-dense arm and 5.0 months in the metronomic arm).

CONCLUSION

Both dose-dense and metronomic temozolomide regimens were well tolerated with modest toxicity. The dose-dense regimen appears promising, with 1-year survival of 80%.

A pilot study of everolimus and gefitinib in the treatment of recurrent glioblastoma (GBM)

Twenty-two patients with recurrent glioblastoma (GBM) were prospectively treated with everolimus and gefitinib, designed to test the combined inhibition of mammalian target of rapamycin (mTOR) and epidermal growth factor receptor (EGFR) as part of a larger clinical trial. The primary endpoint was radiographic response rate. Secondary endpoints included progression-free survival and correlation of molecular profiles with treatment response. 36% of patients had stable disease and 14% a partial response; however, responses were not durable and only one patient was progression-free at six months. Radiographic changes were not well characterized by conventional response criteria, and implied differential effects of therapy within the tumor and/or antiangiogenic effects. EGFR and PTEN status did not clearly predict response to treatment.

Phase 2 trial of dasatinib in target-selected patients with recurrent glioblastoma (RTOG 0627)

BACKGROUND

We conducted a phase II trial to evaluate the efficacy of dasatinib, a multitargeted tyrosine kinase inhibitor, for adults with recurrent glioblastoma (GBM).

METHODS

Eligibility requirements were Karnofsky performance status ≥ 60%; no concurrent hepatic enzyme-inducing anticonvulsants; prior treatment with surgery, radiotherapy, and temozolomide exclusively; and activation or overexpression of ≥ 2 putative dasatinib targets in GBM (ie, SRC, c-KIT, EPHA2, and PDGFR). Using a 2-stage design, 77 eligible participants (27 in stage 1, if favorable, and then 50 in stage 2) were needed to detect an absolute improvement in the proportion of patients either alive and progression-free patients at 6 months (6mPFS) or responding (any duration) from a historical 11% to 25%.

RESULTS

A high rate of ineligibility (27%) to stage 1 precluded a powered assessment of efficacy, but there was also infrequent treatment-related toxicity at 100 mg twice daily. Therefore, the study was redesigned to allow intrapatient escalation by 50 mg daily every cycle as tolerated (stage 1B) before determining whether to proceed to stage 2. Escalation was tolerable in 10 of 17 (59%) participants evaluable for that endpoint; however, among all eligible patients (stages 1 and 1B, n = 50), there were no radiographic responses, median overall survival was 7.9 months, median PFS was 1.7 months, and the 6mPFS rate was 6%. The clinical benefit was insufficient to correlate tested biomarkers with efficacy. The trial was closed without proceeding to stage 2.

CONCLUSIONS

Intraparticipant dose escalation was feasible, but dasatinib was ineffective in recurrent GBM. Clinical trials.gov identified. NCT00423735 (available at http://clinicaltrials.gov/ct2/show/NCT00423735).

Cilengitide in patients with recurrent glioblastoma: the results of NABTC 03-02, a phase II trial with measures of treatment delivery

Cilengitide is a cyclic pentapeptide that is a specific inhibitor of the αvβ3 and αvβ5 integrins. Preclinical studies demonstrate antiangiogenic activity and anti-invasive activity in a number of glioma models. This study was designed to evaluate the efficacy and tumor delivery of cilengitide in patients with recurrent glioblastoma. Patients with recurrent glioblastoma who require a surgical resection for optimal clinical care received 3 intravenous doses of cilengitide at either 500 or 2000 mg (day -8, -4, -1) prior to undergoing tumor resection with corresponding blood samples for plasma to tumor comparisons. After recovery from surgery, patients were treated with cilengitide (2000 mg i.v. twice weekly, maximum of 2 years of treatment). The study accrued 30 patients with recurrent glioblastoma, 26 were evaluable for efficacy. The 6-month progression free survival rate was 12%. Cilengitide was detected in all tumor specimens with higher levels in the group receiving 2000 mg dosing while corresponding plasma concentrations were low, often below the lower limit of detection. These results confirm drug delivery and possibly retention in tumor. This study provides evidence that with established dosing, cilengitide is adequately delivered to the tumor, although as a single agent, efficacy in recurrent glioblastoma is modest. However, these results demonstrating drug delivery to tumor do support continued investigation of this agent as preliminary results from recent studies combining cilengitide with cytotoxic therapies are promising.

An independently validated nomogram for individualized estimation of survival among patients with newly diagnosed glioblastoma: NRG Oncology RTOG 0525 and 0825

Background

Glioblastoma (GBM) is the most common primary malignant brain tumor. Nomograms are often used for individualized estimation of prognosis. This study aimed to build and independently validate a nomogram to estimate individualized survival probabilities for patients with newly diagnosed GBM, using data from 2 independent NRG Oncology Radiation Therapy Oncology Group (RTOG) clinical trials.

Methods

This analysis included information on 799 (RTOG 0525) and 555 (RTOG 0825) eligible and randomized patients with newly diagnosed GBM and contained the following variables: age at diagnosis, race, gender, Karnofsky performance status (KPS), extent of resection, O6-methylguanine-DNA methyltransferase (MGMT) methylation status, and survival (in months). Survival was assessed using Cox proportional hazards regression, random survival forests, and recursive partitioning analysis, with adjustment for known prognostic factors. The models were developed using the 0525 data and were independently validated using the 0825 data. Models were internally validated using 10-fold cross-validation, and individually predicted 6-, 12-, and 24-month survival probabilities were generated to measure the predictive accuracy and calibration against the actual survival status.

Results

A final nomogram was built using the Cox proportional hazards model. Factors that increased the probability of shorter survival included greater age at diagnosis, male gender, lower KPS, not having total resection, and unmethylated MGMT status.

Conclusions

A nomogram that assesses individualized survival probabilities (6-, 12-, and 24-mo) for patients with newly diagnosed GBM could be useful to health care providers for counseling patients regarding treatment decisions and optimizing therapeutic approaches. Free software for implementing this nomogram is provided: http://cancer4.case.edu/rCalculator/rCalculator.html.

Clinical trial end points for high-grade glioma: the evolving landscape

To review the strengths and weaknesses of primary and auxiliary end points for clinical trials among patients with high-grade glioma (HGG). Recent advances in outcome for patients with newly diagnosed and recurrent HGG, coupled with the development of multiple promising therapeutics with myriad antitumor actions, have led to significant growth in the number of clinical trials for patients with HGG. Appropriate clinical trial design and the incorporation of optimal end points are imperative to efficiently and effectively evaluate such agents and continue to advance outcome. Growing recognition of limitations weakening the reliability of traditional clinical trial primary end points has generated increasing uncertainty of how best to evaluate promising therapeutics for patients with HGG. The phenomena of pseudoprogression and pseudoresponse have made imaging-based end points, including overall radiographic response and progression-free survival, problematic. Although overall survival is considered the "gold-standard" end point, recently identified active salvage therapies such as bevacizumab may diminish the association between presalvage therapy and overall survival. Finally, advances in imaging as well as the assessment of patient function and well being have strengthened interest in auxiliary end points assessing these aspects of patient care and outcome. Better appreciation of the strengths and limitations of primary end points will lead to more effective clinical trial strategies. Technical advances in imaging as well as improved survival for patients with HGG support the further development of auxiliary end points evaluating novel imaging approaches as well as measures of patient function and well being.

Systemic high-dose intravenous methotrexate for central nervous system metastases

BACKGROUND

Treatment options for patients with recurrent central nervous system (CNS) metastases are limited. Rapid infusion of high-dose intravenous methotrexate (HD IV MTX) penetrates the blood-brain barrier (BBB) and has reported activity in leptomeningeal metastases.

METHODS

Medical records were reviewed for all patients treated with HD IV MTX (3.5 g/m2) for CNS parenchymal or leptomeningeal metastases. Radiographic response rate, survival, and toxicity were determined.

RESULTS

Thirty-one women and one man with a median age of 52 years (range 33-76) were treated with a total of 141 cycles (median 4, range 1-13). Twenty-nine patients had breast cancer, and one each had cancer of unknown primary (CUP), squamous cell carcinoma of the head and neck, and non-small cell lung cancer (NSCLC). An objective radiographic response and stable disease were each observed in nine patients (28%), and 13 (44%) patients progressed. Prior treatment with low-dose MTX for systemic disease did not affect response (P = 0.8). The median overall survival (n = 32) was 19.9 weeks (range 2.9-135.4+) with one patient alive at 135.4 weeks. Myelosuppression and elevated serum hepatic transaminases were the most common acute toxicities (21% and 9% of HD IV MTX cycles, respectively).

CONCLUSIONS

HD IV MTX is effective in the treatment of CNS metastases with disease control (response or stable) as a best response in 56% of assessable patients. Further study is warranted.

Efficacy of depatuxizumab mafodotin (ABT-414) monotherapy in patients with EGFR-amplified, recurrent glioblastoma: results from a multi-center, international study

PURPOSE

Patients with recurrent glioblastoma (rGBM) have a poor prognosis. Epidermal growth factor receptor (EGFR) gene amplification is present in ~ 50% of glioblastomas (GBMs). Depatuxizumab mafodotin (depatux-m), formerly ABT-414, is an antibody-drug conjugate that preferentially binds cells with EGFR amplification, is internalized and releases a potent antimicrotubule agent, monomethyl auristatin F (MMAF). Here we report the safety, pharmacokinetics, and efficacy of depatux-m monotherapy at the recommended Phase 2 dose (RPTD) in patients with EGFR-amplified, rGBM.

METHODS

M12-356 (NCT01800695) is an open-label study with three escalation and expansion cohorts. Sixty-six patients with EGFR-amplified, rGBM were treated with depatux-m monotherapy at 1.25 mg/kg intravenously every 2 weeks. Adults with measurable rGBM, who were bevacizumab-naïve, with EGFR amplification were eligible.

RESULTS

Among 66 patients, median age was 58 years (range 35-80). All patients were previously treated with radiotherapy/temozolomide. The most common adverse events (AEs) were eye related (91%), including blurred vision (65%), dry eye (29%), keratitis, and photophobia (27% each). Grade 3/4 AEs occurred in 42% of all patients, and ocular Grade 3/4 AEs occurred in 33% of patients overall. One patient (2%) had a Grade 4 ocular AE. Ocular AEs were manageable and usually resolved once treatment with depatux-m ceased. The objective response rate was 6.8%, the 6-month progression-free survival rate was 28.8%, and the 6-month overall survival rate was 72.5%.

CONCLUSION

Depatux-m monotherapy displayed frequent but mostly Grade 1/2 ocular toxicities. A PFS6 of 28.8% was observed in this rGBM population, warranting further study.

Survey of treatment recommendations for anaplastic oligodendroglioma

Anaplastic oligodendroglioma is a malignant brain tumor uniquely sensitive to treatment with both chemotherapy and radiotherapy. There are few prospective clinical trials for newly diagnosed patients and multiple approaches to the treatment of these patients. This study explored the recommended treatment offered by experts in neuro-oncology. A Web-based survey was developed and distributed to 800 members of the Society of Neuro-Oncology (SNO) who had an e-mail address listed with SNO. Questions addressed use of molecular genetic information and treatment recommendations. A total of 99 clinical SNO members (20%) responded. The majority reported practicing at an academic center in the United States. Two-thirds of respondents see more than five patients with newly diagnosed anaplastic oligodendroglioma annually. Molecular genetic testing was requested for more than 75% of patients, and the results significantly influenced treatment recommendations (p = 0.000003). Regardless of molecular genetic status, the most commonly recommended treatment was the use of concurrent temozolomide and radiotherapy followed by adjuvant temozolomide (18%-34%). The current survey demonstrates that although neuro-oncologists have embraced the use of molecular genetic studies in newly diagnosed anaplastic oligodendroglioma, treatment recommendations vary widely and are often independent of the molecular data.

Efficacy and safety of bevacizumab in active brain metastases from non-small cell lung cancer

Bevacizumab is effective for the treatment of non-small cell lung cancer (NSCLC). Ongoing trials are exploring the safety of bevacizumab in patients with inactive, previously treated brain metastases. However, bevacizumab safety and efficacy in the treatment of active brain metastases is unknown. Bevacizumab received accelerated FDA approval for progressive glioblastoma, a primary brain tumor, because of high response rates and low incidence of intracranial hemorrhage. We retrospectively identified patients treated with bevacizumab for active (treatment naïve or progressive) central nervous system (CNS) metastases from NSCLC. MRI scans performed at least 6 weeks after initiating bevacizumab were assessed for response. There were six patients, four women and two men with a median age of 60 years (range 59-77) at initiation of bevacizumab. Five patients had progressive CNS metastases despite prior treatment including surgery, radiotherapy, and/or chemotherapy; one patient had treatment-naïve brain metastases. Two patients had leptomeningeal metastases, isolated or coexistent with parenchymal brain metastases in one patient each. Bevacizumab was administered alone to one patient and in combination with various cytotoxic chemotherapies in the others. Toxicity included an asymptomatic (Grade 1) intra-tumoral hemorrhage which occurred in one of three patients receiving concurrent anticoagulation with bevacizumab. There was no recurrent CNS bleeding in two patients with a prior history of such hemorrhage. Best CNS response (RECIST) was partial in two, stable disease in three, and progression in one. Median progression-free survival (PFS) was 7.8 months and median overall survival (OS) was 14.1 months following initiation of bevacizumab. Clinical benefit was also observed in the form of improved symptoms and reduced corticosteroid requirements. Bevacizumab should be used with caution in patients with active CNS metastases pending additional safety data. This series suggests bevacizumab may be safe and effective for progressive brain metastases from NSCLC and deserves further study.