Phase II study of carboplatin, irinotecan, and bevacizumab for bevacizumab naïve, recurrent glioblastoma

We evaluated the efficacy of carboplatin, irinotecan, and bevacizumab among bevacizumab-naïve, recurrent glioblastoma (GBM) patients in a phase 2, open-label, single arm trial. Forty eligible patients received carboplatin (area under the plasma curve [AUC] 4 mg/ml-min) on day one, while bevacizumab (10 mg/kg) and irinotecan (340 mg/m(2) for patients on CYP3A-enzyme-inducing anti-epileptics [EIAEDs] and 125 mg/m(2) for patients not on EIAEDs) were administered on days 1 and 14 of every 28-day cycle. Patients were evaluated after each of the first two cycles and then after every other cycle. Treatment continued until progressive disease, unacceptable toxicity, non-compliance, or voluntary withdrawal. The primary endpoint was progression-free survival at 6 months (PFS-6) and secondary endpoints included safety and median overall survival (OS). All patients had progression after standard therapy. The median age was 51 years. Sixteen patients (40%) had a KPS of 90-100, while 27 (68%) were at first progression. The median time from original diagnosis was 11.4 months. The PFS-6 rate was 46.5% (95% CI: 30.4, 61.0%) and the median OS was 8.3 months [95% confidence interval (CI): 5.9, and 10.7 months]. Grade 4 events were primarily hematologic and included neutropenia and thrombocytopenia in 20 and 10%, respectively. The most common grade 3 events were neutropenia, thrombocytopenia, fatigue, and infection in 25, 20, 13, and 10%, respectively. Eleven patients (28%) discontinued study therapy due to toxicity and 17 patients (43%) required dose modification. One patient died due to treatment-related intestinal perforation. The addition of carboplatin and irinotecan to bevacizumab significantly increases toxicity but does not improve anti-tumor activity to that achieved historically with single-agent bevacizumab among bevacizumab-naïve, recurrent GBM patients. (ClinicalTrials.gov number NCT00953121).

A review of VEGF/VEGFR-targeted therapeutics for recurrent glioblastoma

Glioblastoma, the most common primary malignant brain tumor among adults, is a highly angiogenic and deadly tumor. Angiogenesis in glioblastoma, driven by hypoxia-dependent and independent mechanisms, is primarily mediated by vascular endothelial growth factor (VEGF), and generates blood vessels with distinctive features. The outcome for patients with recurrent glioblastoma is poor because of ineffective therapies. However, recent encouraging rates of radiographic response and progression-free survival, and adequate safety, led the FDA to grant accelerated approval of bevacizumab, a humanized monoclonal antibody against VEGF, for the treatment of recurrent glioblastoma in May 2009. These results have triggered significant interest in additional antiangiogenic agents and therapeutic strategies for patients with both recurrent and newly diagnosed glioblastoma. Given the potent antipermeability effect of VEGF inhibitors, the Radiologic Assessment in Neuro-Oncology (RANO) criteria were recently implemented to better assess response among patients with glioblastoma. Although bevacizumab improves survival and quality of life, eventual tumor progression is the norm. Better understanding of resistance mechanisms to VEGF inhibitors and identification of effective therapy after bevacizumab progression are currently a critical need for patients with glioblastoma.

Trigeminal Schwannomas: Skull Base Approaches and Operative Results in 105 Patients

BACKGROUND:

Trigeminal schwannomas make up 0.8% to 8% of all intracranial schwannomas.

OBJECTIVE:

To analyze our surgical experience with trigeminal schwannomas.

METHODS:

We performed 107 operations on 105 patients harboring trigeminal schwannomas over the past 30 years. We classified the tumors as peripheral, ganglion cavernous, posterior fossa root, and dumbbell types according to the portion of the nerve that gave rise to the tumor.

RESULTS:

Fourteen were peripheral-type tumors (13.1%), 39 (36.4%) were ganglion cavernous type, 22 (20.6%) were posterior fossa root type, and 32 (30.0%) were dumbbell type. Sixty-five tumors were solid, 35 were mixed, and only 7 were cystic. Among solid tumors, 14 were vascular, fibrous, and adherent to adjacent structures. Total or near-total removal was performed in 86 cases (81.9%), and subtotal removal was achieved in 18 (17.1%). The most common symptom was facial hypesthesia, occurring in 69 patients. This symptom improved in 11 patients, persisted in 50 patients, and worsened in 8 patients after surgery. New postoperative hypesthesia was observed in 8 patients. The second most common symptom was facial pain, observed in 24 patients. Facial pain subsided in 22 and persisted in 2 patients after surgery. Diplopia was observed in 21 patients. This symptom improved postoperatively in 14 patients, persisted in 6 patients, and worsened in 1 patient.

CONCLUSION:

The present series demonstrates acceptable results using microsurgical treatment to remove trigeminal schwannomas. Pain and diplopia may be relieved after surgery; however, hypesthesia frequently remains or may be worsened by surgery.

Exercise behavior, functional capacity, and survival in adults with malignant recurrent glioma

PURPOSE

Identifying strong markers of prognosis are critical to optimize treatment and survival outcomes in patients with malignant recurrent glioma. We investigated the prognostic significance of exercise behavior and functional capacity in this population.

PATIENTS AND METHODS

Using a prospective design, 243 patients with WHO grades 3 to 4 recurrent malignant glioma and Karnofsky performance status (KPS) ≥ 70 completed a self-administered questionnaire that assessed exercise behavior and performed a 6-minute walk test (6MWT) to assess functional capacity. Cox proportional models were used to estimate the risk of all-cause mortality according to 6MWT distance (6MWD; < 390 meters, 390-489 meters, > 489 meters) and exercise behavior (metabolic equivalent [MET] -h/wk) adjusted for KPS and other important clinical factors.

RESULTS

Median follow-up was 27.43 months. During this period, 149 deaths were recorded (61% of the total sample). Exercise behavior was an independent predictor of survival (P = .0081). Median survival was 13.03 months for patients reporting < 9 MET-h/wk relative to 21.84 months for those reporting ≥ 9 MET-h/wk. Exercise behavior added incremental prognostic value beyond that provided by KPS, age, sex, grade, and number of prior progressions (P < .001). Compared with patients reporting < 9 MET-h/wk, the adjusted hazard ratio for mortality was 0.64 (95% CI, 0.46 to 0.91) for patients reporting ≥ 9 MET-h/wk. Functional capacity was not an independent predictor of prognosis.

CONCLUSION

Exercise behavior is a strong independent predictor of survival that provides incremental prognostic value to KPS as well as traditional markers of prognosis in malignant recurrent glioma.

A phase I trial of the farnesyl transferase inhibitor, SCH 66336, with temozolomide for patients with malignant glioma

We conducted a phase I clinical trial of the combination of SCH 66336 with temozolomide administered on the standard 5-day dosing schedule. The primary objective was to determine the maximum tolerated dose and dose limiting toxicity (DLT) of twice daily SCH 66336 when administered with temozolomide to adults with malignant glioma previously treated with radiation therapy. Patients were enrolled to two strata: stratum A, patients not on enzyme-inducing antiepileptic drugs (EIAEDs); stratum B, patients receiving EIAEDs. Temozolomide was administered at a dose of 150 mg/m(2) daily for five days for the first 28-day cycle and escalated to 200 mg/m(2), during subsequent cycles. SCH 66336 was administered twice daily on a continuous daily dosing schedule. The starting dose of SCH 66336 was 75 mg twice daily for stratum A and 125 mg twice daily for stratum B. Cohorts of 3-6 patients were treated per dose level until DLT was observed. Thirty six patients were enrolled on study, including 21 patients on stratum A and 15 on stratum B. All DLTs were grade 3 events and included hepatic, gastrointestinal, renal, thrombotic and constitutional events. No grade 4 or 5 toxicities were observed. The phase II dose of SCH 66336 when combined with temozolomide is 150 mg twice daily for patients not on EIAEDs and 175 mg twice daily for patients on EIAEDs.

Phase 2 study of carboplatin, irinotecan, and bevacizumab for recurrent glioblastoma after progression on bevacizumab therapy

BACKGROUND

The efficacy of carboplatin, irinotecan, and bevacizumab among recurrent glioblastoma (GBM) patients after prior progression on bevacizumab therapy in a phase 2, open-label, single-arm trial was evaluated.

METHODS

Eligible patients received carboplatin (area under the plasma curve [AUC] 4 mg/ml-min) on day 1, whereas bevacizumab (10 mg/kg) and irinotecan (340 mg/m(2) for patients on CYP3A enzyme-inducing anti-epileptics [EIAEDs] and 125 mg/m(2) for patients not on EIAEDs) were administered on days 1 and 14 of every 28-day cycle. Patients were evaluated after each of the first 2 cycles and then after every other cycle. Treatment continued until progressive disease, unacceptable toxicity, noncompliance, or voluntary withdrawal. The primary end point was progression-free survival at 6 months (PFS-6), and secondary end points included safety and median overall survival (OS).

RESULTS

All patients had progression on at least 1 prior bevacizumab regimen and 56% enrolled after either second or third overall progression. The median OS was 5.8 months (95% confidence interval [CI], 4.0-7.0 months) and PFS-6 rate was 16% (95% CI, 5.0%-32.5%). The most common grade 3 or 4 events were hematologic and occurred in 29% of cycles. Nine patients (38%) required dose modification. There were no treatment-related deaths.

CONCLUSIONS

Carboplatin, irinotecan, and bevacizumab was associated with modest activity and adequate safety among recurrent GBM patients who progressed on bevacizumab previously.

The addition of bevacizumab to standard radiation therapy and temozolomide followed by bevacizumab, temozolomide, and irinotecan for newly diagnosed glioblastoma

PURPOSE

To determine if the addition of bevacizumab to radiation therapy and temozolomide, followed by bevacizumab, temozolomide, and irinotecan, for newly diagnosed glioblastoma patients is safe and effective.

EXPERIMENTAL DESIGN

A total of 75 patients with newly diagnosed glioblastoma were enrolled in the phase II trial that investigated the addition of bevacizumab to standard radiation therapy and daily temozolomide followed by the addition of bevacizumab and irinotecan to adjuvant temozolomide. The bevacizumab was given at 10 mg/kg every 14 days beginning a minimum of 4 weeks postcraniotomy. Two weeks after radiation therapy, the patients began 6 to 12 cycles of 5-day temozolomide with bevacizumab and irinotecan every 14 days. The primary endpoint was the proportion of patients alive 16 months after informed consent.

RESULTS

The therapy had moderate toxicity. Three patients, one of whom had a grade 2 central nervous system hemorrhage, came off study during radiation therapy. Seventy patients started the postradiation therapy, and 16 (23%) terminated this adjuvant therapy early because of toxicity. The median overall survival was 21.2 months (95% CI: 17.2-25.4), and 65% of the patients were alive at 16 months (95% CI: 53.4-74.9). The median progression-free survival was 14.2 months (95% CI: 12-16).

CONCLUSION

The addition of bevacizumab to standard radiation therapy and temozolomide, followed by bevacizumab, irinotecan, and temozolomide, for the treatment of newly diagnosed glioblastoma has moderate toxicity and may improve efficacy compared with historical controls. The results from phase III trials are required before the role of bevacizumab for newly diagnosed glioblastoma is established.

Monitoring radiographic brain tumor progression

Determining radiographic progression in primary malignant brain tumors has posed a significant challenge to the neuroncology community. Glioblastoma multiforme (GBM, WHO Grade IV) through its inherent heterogeneous enhancement, growth patterns, and irregular nature has been difficult to assess for progression. Our ability to detect tumor progression radiographically remains inadequate. Despite the advanced imaging techniques, detecting tumor progression continues to be a clinical challenge. Here we review the different criteria used to detect tumor progression, and highlight the inherent challenges with detection of progression.

Impact of Tumor Histology on Resectability and Neurological Outcome in Primary Intramedullary Spinal Cord Tumors: A Single-Center Experience With 102 Patients

BACKGROUND:

Surgical outcomes for intramedullary spinal cord tumors are affected by many variables including tumor histology and preoperative neurological function.

OBJECTIVE:

To analyze the impact of tumor histology on neurological outcome in primary intramedullary spinal cord tumors.

METHODS:

A retrospective review of 102 consecutive patients with intramedullary spinal cord tumors treated at a single institution between January 1998 and March 2009.

RESULTS:

Ependymomas were the most common tumors with 55 (53.9%), followed by 21 astrocytomas (20.6%), 12 hemangioblastomas (11.8%), and 14 miscellaneous tumors (13.7%). Gross total resection was achieved in 50 ependymomas (90.9%), 3 astrocytomas (14.3%), 11 hemangioblastomas (91.7%), and 12 miscellaneous tumors (85.7%). At a mean follow-up of 41.8 months (range, 1-132 months), we observed recurrences in 4 ependymoma cases (7.3%), 10 astrocytoma cases (47.6%), 1 miscellaneous tumor case (7.1%), and no recurrence in hemangioblastoma cases. When analyzed by tumor location, there was no difference in neurological outcomes (P = .66). At the time of their last follow-up visit, 11 patients (20%) with an ependymoma improved, 38 (69%) remained the same, and 6 (10.9%) worsened. In patients with an astrocytoma, 1 (4.8%) improved, 10 (47.6%) remained the same, and 10 (47.6%) worsened. One patient (8.3%) with a hemangioblastoma improved and 11 (91.7%) remained the same. No patient with a hemangioblastoma worsened. In the miscellaneous tumor group, 2 (14.3%) improved, 10 (71.4%) remained the same, and 2 (14.3%) worsened. Preoperative neurological status (P = .02), tumor histology (P = .005), and extent of resection (P &lt; .0001) were all predictive of functional neurological outcomes.

CONCLUSION:

Tumor histology is the most important predictor of neurological outcome after surgical resection because it predicts resectability and recurrence.

Retrosigmoid suprafloccular transhorizontal fissure approach for resection of brainstem cavernous malformation

OBJECTIVE

This study examined the usefulness of a surgical approach (retrosigmoid suprafloccular transhorizontal fissure approach) for resection of brainstem cavernous malformations (CMs).

METHODS

An anatomic study concerning the retrosigmoid suprafloccular transhorizontal fissure approach was performed with 3 cadaveric heads. Clinical course was retrospectively reviewed for 10 patients who underwent microsurgical resection of brainstem CMs with this approach. Medical, surgical, and neuroimaging records of these patients were evaluated.

RESULTS

In the anatomic study, after standard suboccipital retrosigmoid craniotomy, the horizontal fissure on the petrosal surface of the cerebellum was dissected between the superior semilunar lobule and flocculus. With this approach, the root entry zone of the trigeminal nerve and the middle cerebellar peduncle could be exposed by superior retraction of the superior semilunar lobule. The lateral surface of the pons was then easily visible around the root entry zone. When this approach was used for 10 brainstem CMs, complete resection was achieved in 9 patients (90%). No mortality was encountered in this study. New neurological deficits occurred in the early postoperative period for 4 patients but were transient in 3 patients. Neurological status at final follow-up was improved in 4 patients (40%), unchanged in 5 patients (50%), and worse in 1 patient (10%) compared with preoperative conditions.

CONCLUSION

The retrosigmoid suprafloccular transhorizontal fissure approach is useful for the resection of lateral pontine CMs.

Greater chemotherapy-induced lymphopenia enhances tumor-specific immune responses that eliminate EGFRvIII-expressing tumor cells in patients with glioblastoma

Epidermal growth factor receptor variant III (EGFRvIII) is a tumor-specific mutation widely expressed in glioblastoma multiforme (GBM) and other neoplasms, but absent from normal tissues. Immunotherapeutic targeting of EGFRvIII could eliminate neoplastic cells more precisely but may be inhibited by concurrent myelosuppressive chemotherapy like temozolomide (TMZ), which produces a survival benefit in GBM. A phase II, multicenter trial was undertaken to assess the immunogenicity of an experimental EGFRvIII-targeted peptide vaccine in patients with GBM undergoing treatment with serial cycles of standard-dose (STD) (200 mg/m(2) per 5 days) or dose-intensified (DI) TMZ (100 mg/m(2) per 21 days). All patients receiving STD TMZ exhibited at least a transient grade 2 lymphopenia, whereas those receiving DI TMZ exhibited a sustained grade 3 lymphopenia (<500 cells/μL). CD3(+) T-cell (P = .005) and B-cell (P = .004) counts were reduced significantly only in the DI cohort. Patients in the DI cohort had an increase in the proportion of immunosuppressive regulatory T cells (T(Reg); P = .008). EGFRvIII-specific immune responses developed in all patients treated with either regimen, but the DI TMZ regimen produced humoral (P = .037) and delayed-type hypersensitivity responses (P = .036) of greater magnitude. EGFRvIII-expressing tumor cells were also eradicated in nearly all patients (91.6%; CI(95): 64.0%-99.8%; P < .0001). The median progression-free survival (15.2 months; CI(95): 11.0-18.5 months; hazard ratio [HR] = 0.35; P = .024) and overall survival (23.6 months; CI(95): 18.5-33.1 months; HR = 0.23; P = .019) exceeded those of historical controls matched for entry criteria and adjusted for known prognostic factors. EGFRvIII-targeted vaccination induces patient immune responses despite therapeutic TMZ-induced lymphopenia and eliminates EGFRvIII-expressing tumor cells without autoimmunity.

Immunologic escape after prolonged progression-free survival with epidermal growth factor receptor variant III peptide vaccination in patients with newly diagnosed glioblastoma

PURPOSE

Immunologic targeting of tumor-specific gene mutations may allow precise eradication of neoplastic cells without toxicity. Epidermal growth factor receptor variant III (EGFRvIII) is a constitutively activated and immunogenic mutation not expressed in normal tissues but widely expressed in glioblastoma multiforme (GBM) and other neoplasms.

PATIENTS AND METHODS

A phase II, multicenter trial was undertaken to assess the immunogenicity of an EGFRvIII-targeted peptide vaccine and to estimate the progression-free survival (PFS) and overall survival (OS) of vaccinated patients with newly diagnosed EGFRvIII-expressing GBM with minimal residual disease. Intradermal vaccinations were given until toxicity or tumor progression was observed. Sample size was calculated to differentiate between PFS rates of 20% and 40% 6 months after vaccination.

RESULTS

There were no symptomatic autoimmune reactions. The 6-month PFS rate after vaccination was 67% (95% CI, 40% to 83%) and after diagnosis was 94% (95% CI, 67% to 99%; n = 18). The median OS was 26.0 months (95% CI, 21.0 to 47.7 months). After adjustment for age and Karnofsky performance status, the OS of vaccinated patients was greater than that observed in a control group matched for eligibility criteria, prognostic factors, and temozolomide treatment (hazard ratio, 5.3; P = .0013; n = 17). The development of specific antibody (P = .025) or delayed-type hypersensitivity (P = .03) responses to EGFRvIII had a significant effect on OS. At recurrence, 82% (95% CI, 48% to 97%) of patients had lost EGFRvIII expression (P < .001).

CONCLUSION

EGFRvIII-targeted vaccination in patients with GBM warrants investigation in a phase III, randomized trial.

Critical Assessment of Operative Approaches for Hearing Preservation in Small Acoustic Neuroma Surgery

BACKGROUND

For hearing preservation in acoustic neuroma (AN) surgery, the middle fossa (MF) or retrosigmoid (RS) approach can be used. Recent literature advocates the use of the MF approach, especially for small ANs.

OBJECTIVE

To present our critical analysis of operative results comparing these 2 approaches.

METHODS

We reviewed 504 consecutive AN resections performed between November 1998 and September 2007 and identified 43 MF and 82 RS approaches for tumors smaller than 1.5 cm during hearing preservation surgery. Individual cases were examined postoperatively with respect to hearing ability, facial nerve activity, operative time, blood loss, and symptoms resulting from retraction of the cerebellar or temporal lobes.

RESULTS

Good hearing function (American Academy of Otolaryngology-Head and Neck Surgery class B or better) was preserved in 76.7% of patients undergoing surgery via the MF approach and in 73.2% of the RS group (P = .9024). Temporary facial nerve weakness was more frequent in the MF group (P = .0249). However, late (8–12 months) follow-up examinations showed good recovery in both groups. The mean operative time was 7.45 hours for the MF group and 5.2 hours for the RS group (P = .0318). The mean blood loss was 280.5 mL for the MF group and 80.8 mL for the RS group (P &lt; .0001). Temporary symptoms of temporal lobe edema (drowsiness or speech disturbance) were noted in 6 MF cases. No cerebellar dysfunction was noted in the RS group.

CONCLUSIONS

Although hearing and facial nerve function assessed at approximately 1 year was similar with these 2 approaches, the RS approach provided several advantages over the MF approach for ANs smaller than 1.5 cm.

Unilateral hypoglossal nerve palsy caused by an intraneural ganglion cyst

The authors describe a rare case of unilateral hypoglossal nerve palsy caused by an intraneural ganglion cyst. Three similar cases have been reported with pathological classification still under consideration. One case was classified as an intraneural ganglion cyst and 2 cases were classified as atlantooccipital joint synovial cysts.

Poor drug distribution as a possible explanation for the results of the PRECISE trial

Object

Convection-enhanced delivery (CED) is a novel intracerebral drug delivery technique with considerable promise for delivering therapeutic agents throughout the CNS. Despite this promise, Phase III clinical trials employing CED have failed to meet clinical end points. Although this may be due to inactive agents or a failure to rigorously validate drug targets, the authors have previously demonstrated that catheter positioning plays a major role in drug distribution using this technique. The purpose of the present work was to retrospectively analyze the expected drug distribution based on catheter positioning data available from the CED arm of the PRECISE trial.

Methods

Data on catheter positioning from all patients randomized to the CED arm of the PRECISE trial were available for analyses. BrainLAB iPlan Flow software was used to estimate the expected drug distribution.

Results

Only 49.8% of catheters met all positioning criteria. Still, catheter positioning score (hazard ratio 0.93, p = 0.043) and the number of optimally positioned catheters (hazard ratio 0.72, p = 0.038) had a significant effect on progression-free survival. Estimated coverage of relevant target volumes was low, however, with only 20.1% of the 2-cm penumbra surrounding the resection cavity covered on average. Although tumor location and resection cavity volume had no effect on coverage volume, estimations of drug delivery to relevant target volumes did correlate well with catheter score (p < 0.003), and optimally positioned catheters had larger coverage volumes (p < 0.002). Only overall survival (p = 0.006) was higher for investigators considered experienced after adjusting for patient age and Karnofsky Performance Scale score.

Conclusions

The potential efficacy of drugs delivered by CED may be severely constrained by ineffective delivery in many patients. Routine use of software algorithms and alternative catheter designs and infusion parameters may improve the efficacy of drugs delivered by CED.

Skull base training and education using an artificial skull model created by selective laser sintering

INTRODUCTION

Practicing skull base approaches on cadavers affords the surgeon a chance to learn complex anatomical relationships and to practice surgical skills. However, there are ethical or legal problems in obtaining cadaver material in some countries. In addition, there is always risk of transmitting infections with cadaveric material. In order to get around these problems, we created a whole skull model which reproduces the detailed anatomy within the skull base using a selective laser sintering (SLS) technique.

MATERIALS AND METHODS

The first author's head was scanned using multidetector-row computed tomography. The data were reconstructed and converted into the standard triangulation language file system. Powdered material comprised of polyamide nylon and glass beads was laser-sintered in accord with the data derived from the head CT. The model was dissected under a surgical microscope using a high-speed drill, suction, and other surgical instruments.

RESULTS AND DISCUSSION

The appearance of both inner and outer cranial surfaces, including sutures, foramens, fissures, and protrusions, were clearly demonstrated. The artificial mastoid did not melt from the heat of the drill when a mastoidectomy was performed. The anatomical structures inside the mastoid and of paranasal sinuses were accurately reproduced in the model.

CONCLUSION

The model created using SLS should be very useful for the teaching skull base approaches avoiding the ethical, legal, and infection problems inherent in cadavers.

Changes in functional performance measures in adults undergoing chemoradiation for primary malignant glioma: a feasibility study

PURPOSE

To investigate the feasibility of longitudinal assessment of functional performance measures in newly diagnosed postsurgical malignant glioma patients.

METHODS

Patients with histologically confirmed, clinically stable, postsurgical, and previously untreated high-grade glioma (HGG) or low-grade glioma (LGG) were studied. Using a prospective design, all participants performed a cardiopulmonary exercise test with expired gas analysis to assess cardiorespiratory function (VO(2peak)) immediately following surgical resection (mean, 10 days). Additional functional outcomes were skeletal muscle cross-sectional area (CSA) via magnetic resonance imaging, isokinetic muscle strength (isokinetic dynamometry), and body composition (air displacement plethysmography). Quality of life (QOL) was assessed by the Functional Assessment of Cancer Therapy-Brain scale. All study assessments were repeated at 6 and 24 weeks following surgery.

RESULTS

Thirty-five patients (HGG, n = 25; LGG, n = 10) completed baseline assessments. Of these, 20 HGG (80%) and nine LGG (90%) and 15 HGG (60%) and nine LGG (90%) patients completed study assessments at 6 weeks and 24 weeks, respectively. Intention-to-treat analyses indicated several significant time-by-group interactions, with favorable improvements in functional and QOL endpoints from baseline to 24 weeks in the LGG cohort and unfavorable changes in the HGG cohort. Per-protocol analyses including participants assessed at all three study timepoints indicated significant improvements in VO(2peak) and fatigue from baseline to 24 weeks in the HGG cohort; peak workload, body composition, and muscle strength improved from baseline to 6 weeks (all p-values < .05).

CONCLUSIONS

Longitudinal quantitative functional assessments are safe and feasible among select patients undergoing chemoradiation for primary malignant glioma. Large prospective studies investigating the clinical importance of these measures appear warranted.

An eclectic review of the history of peripheral nerve surgery

We take our present concepts of nerve repair for granted. In fact, the pioneers who established these principles traveled a road filled with erroneous dogma, bad advice, and misleading data. The lessons learned from a review of the history of peripheral nerve surgery are applicable to all neurosurgical disciplines. In honor of Dr. David Kline's distinguished career, we will review 3 aspects of the history of peripheral nerve surgery: Can an injured nerve regain function? How do peripheral nerves regenerate? When should a neuroma in continuity be resected?

Quantitative assessment of cardiorespiratory fitness, skeletal muscle function, and body composition in adults with primary malignant glioma

BACKGROUND

The study was undertaken to evaluate cardiorespiratory fitness, skeletal muscle function, and body composition of patients with newly diagnosed and untreated, postsurgical primary malignant glioma.

METHODS

By using a cross-sectional design, patients with clinically stable (10 +/- 7 days postsurgery) high-grade glioma (HGG; n = 25) or low-grade glioma (LGG; n = 10) were studied. Participants performed a cardiopulmonary exercise test (CPET) with expired gas analysis to assess cardiorespiratory fitness (peak oxygen consumption, VO2peak). Other physiological outcomes included skeletal muscle cross-sectional area (CSA; magnetic resonance imaging), isokinetic muscle strength (isokinetic dynamometer), and body composition (air displacement plethysmography). Quality of life was assessed with the Functional Assessment of Cancer Therapy-Brain scale.

RESULTS

CPET was a feasible and safe procedure to assess VO2peak, with no serious adverse events. VO2peak indexed to total body weight and lean body mass (LBM) for both groups was 13.0 mL x weight x min(-1) and 19 mL x LBM x min(-1), the equivalent to 59% and 38% below age- and sex-predicted normative values, respectively. Skeletal muscle strength and mid-thigh CSA were lower in HGG relative to LGG patients (83 vs 125 Nm, P = .025; 94 vs 119 cm2, P = .171, respectively). Skeletal muscle isokinetic strength, CSA, and body composition outcomes predicted VO2peak (r = -0.59 to 0.68, P < .05).

CONCLUSIONS

Postsurgical glioma patients have markedly reduced cardiorespiratory fitness, isokinetic strength, and CSA. Prospective studies are now required to determine whether such abnormalities influence treatment toxicity and clinical outcome as well as to test the effect of appropriately selected interventions to prevent and/or mitigate dysfunction.

An epidermal growth factor receptor variant III-targeted vaccine is safe and immunogenic in patients with glioblastoma multiforme

Conventional therapies for glioblastoma multiforme (GBM) fail to target tumor cells exclusively, such that their efficacy is ultimately limited by nonspecific toxicity. Immunologic targeting of tumor-specific gene mutations, however, may allow more precise eradication of neoplastic cells. The epidermal growth factor receptor variant III (EGFRvIII) is a consistent and tumor-specific mutation widely expressed in GBMs and other neoplasms. The safety and immunogenicity of a dendritic cell (DC)-based vaccine targeting the EGFRvIII antigen was evaluated in this study. Adults with newly diagnosed GBM, who had undergone gross-total resection and standard conformal external beam radiotherapy, received three consecutive intradermal vaccinations with autologous mature DCs pulsed with an EGFRvIII-specific peptide conjugated to keyhole limpet hemocyanin. The dose of DCs was escalated in cohorts of three patients. Patients were monitored for toxicity, immune response, radiographic and clinical progression, and death. No allergic reactions or serious adverse events were seen. Adverse events were limited to grade 2 toxicities. The maximum feasible dose of antigen-pulsed mature DCs was reached at 5.7 x 10(7) +/- 2.9 x 10(7) SD without dose-limiting toxicity. EGFRvIII-specific immune responses were evident in most patients. The mean time from histologic diagnosis to vaccination was 3.6 +/- 0.6 SD months. Median time to progression from vaccination was 6.8 months [95% confidence interval (C.I.(95)), 2.5-8.8], and median survival time from vaccination was 18.7 months (C.I.(95), 14.5-25.6). Overall median survival from time of histologic diagnosis was 22.8 months (C.I.(95), 17.5-29). This study establishes the EGFRvIII mutation as a safe and immunogenic tumor-specific target for immunotherapy.

Metronomic chemotherapy with daily, oral etoposide plus bevacizumab for recurrent malignant glioma: a phase II study

Background:

We evaluated bevacizumab with metronomic etoposide among recurrent malignant glioma patients in a phase 2, open-label trial.

Methods:

A total of59 patients, including 27 with glioblastoma (GBM) and 32 with grade 3 malignant glioma, received 10 mg kg⁻¹ bevacizumab biweekly and 50 mg m⁻² etoposide daily for 21 consecutive days each month. The primary end point was a 6-month progression-free survival, and secondary end points included safety and overall survival. Vascular endothelial growth factor (VEGF), VEGFR-2, carbonic anhydrase 9 (CA9) and hypoxia-inducible factor-2α (HIF-2α) were assessed semiquantitatively in archival tumours using immunohistochemistry and were correlated with outcome.

Results:

Among grade 3 and GBM patients, the 6-month progression-free survivals were 40.6% and 44.4%, the radiographic response rates were 22% and 37% and the median survivals were 63.1 and 44.4 weeks, respectively. Hypertension predicted better outcome among both grade 3 and GBM patients, whereas high CA9 and low VEGF were associated with poorer progression-free survival (PFS) among those with GBM. The most common grade ⩾3 adverse events included neutropaenia (24%), thrombosis (12%), infection (8%) and hypertension (3%). Two patients had asymptomatic, grade 1 intracranial haemorrhage and one on-study death occurred because of pulmonary embolism.

Conclusion:

Bevacizumab with metronomic etoposide has increased toxicity compared with previous reports of bevacizumab monotherapy. Its anti-tumour activity is similar to that of bevacizumab monotherapy or bevacizumab plus irinotecan. (ClinicalTrials.gov: NCT00612430).

Simple identification of the third segment of the extracranial vertebral artery by extreme lateral inferior transcondylar-transtubercular exposure (ELITE)

PURPOSE

The exposure of the third segment of the extracranial vertebral artery (V3) is an important step in the extreme lateral inferior transcondylar-transtubercular exposure (ELITE) approach. The muscular suboccipital triangle provides one of the landmarks to identify the V3 segment; however, identification of this triangle and dissection of the V3 segment is not always straightforward in the actual surgery. Blind dissection below the level of the foramen magnum can lead to vertebral artery injury. While the surgeon may be able to readily define the V3 segment of the vertebral artery by feeling its pulse, it is important to have a safe systematic approach to finding the V3 segment when the vessel is illusive. We propose a simple method to identify the V3 segment avoiding accidental injury of the vertebral artery.

METHODS

Sixteen cadaver heads (using both sides) were prepared by injecting red- or blue-coloured silicone into their arteries and veins, respectively. We performed an ELITE bilaterally on each cadaver head following four key bony landmarks. A postauricular lazy S-shaped skin incision was made centered just behind the mastoid tip. The posterior neck muscles were cut along the line of the skin incision behind the attachment of the sternocleidomastoid muscle to expose the occipital bone. All the incised muscles were reflected anteriorly as the ELITE is a dorsolateral approach. A suboccipital craniotomy was made exposing the posterior half of the sigmoid sinus up to the inferior retrosigmoid point (point A). The foramen magnum was opened after the craniotomy was completed. The dura on the foramen magnum was followed posteriorly in order to identify the occipital midline dural point (point B) that is identified by the bony ridge at the junction of the posterior fossa dura on the foramen magnum and the posterior most aspect of the spinal dura. The posterior tubercle of C1 (point C) was identified directly inferior to Point B. The posterior arch of C1 was followed anteriorly from the tubercle to find the "J-groove", which cradles the vertebral artery (point D). The V3 segment lies above this groove, covering the paravertebral venous plexus. We measured the distances between the landmarks introduced above after completion of the exposure.

RESULTS

The distance between points A and B was 30.5 +/- 5.6 mm, points B-C was 10.4 +/- 2.3 mm, points C-D was 19.1 +/- 3.8 mm. The V3 segment was identified using the anatomical relationships described above in all heads. In no cadaver specimen was the artery injured.

CONCLUSIONS

Identification of the V3 segment of the vertebral artery by systematically detecting the four anatomical points defined above is simple and much safer than a direct dissection below the foramen magnum.

Hearing preservation in surgery for large vestibular schwannomas

OBJECT

Hearing preservation remains a challenging problem in vestibular schwannoma (VS) surgery. The ability to preserve hearing in patients with large tumors is subject to particular difficulty. In this study, the authors focus on hearing preservation in patients harboring large VSs.

METHODS

A total of 344 consecutive patients underwent surgical removal of VSs over the past 9 years. Of these 344 cases, 195 VSs were > 20 mm in maximum cisternal diameter. Of the 195 cases, hearing preservation surgery was attempted for 54 patients who had a Class A, B, C, or D preoperative hearing level; that is, a pure tone average <or= 60 dB and speech discrimination score >or= 50% according to the Sanna/Fukushima classification. The tumors were classified as moderately large (21-30 mm based on the largest extrameatal diameter), large (31-40 mm), and giant (>or= 41 mm) according to the international criteria. The authors categorized patients with Class A, B, C, D, or E hearing (pure tone average <or= 80 dB and speech discrimination score >or= 40%) as having preserved hearing postoperatively.

RESULTS

Forty-one tumors (75.9%) were totally removed and 13 (24.1%) had near-total removal. Of the 54 patients, 29 maintained their hearing postoperatively; the overall hearing preservation rate was 53.7%. Analysis based on the preoperative hearing level showed that hearing was preserved in 14 (77.8%) of 18 cases for Class A; in 8 (47.1%) of 17 cases for Class B; in 4 (57.1%) of 7 cases for Class C; and in 3 (25.0%) of 12 cases for Class D. In addition, according to the analysis based on the tumor size, 20 (52.6%) of 38 patients with moderately large tumors retained their hearing, as did 5 (50.0%) of 10 patients with large tumors and 4 (66.7%) of 6 patients with giant tumors. Complications included 2 cases of bacterial meningitis that were cured by intravenous injection of antibiotics, 3 cases of subcutaneous CSF leakage that resolved without any surgical repair, and 1 case of temporary abducent nerve palsy. There were no deaths in this series.

CONCLUSIONS

The results indicate that successful hearing preservation surgery in large VSs is possible with meticulous technique and attention to adhesions between the tumor and the cochlear nerves.