Applied Precision Cancer Medicine in Neuro-Oncology

Brain tumours that are refractory to treatment have a poor prognosis and constitute a major challenge in offering effective treatment strategies. By targeting molecular alterations, precision cancer medicine may be a viable option for the treatment of brain tumours. In this retrospective analysis of our PCM platform, we describe the molecular profiling of primary brain tumours from 50 patients. Tumour samples of the patients were examined by a 161-gene next-generation sequencing panel, immunohistochemistry, and fluorescence in situ hybridization (FISH). We identified 103 molecular aberrations in 36 (72%) of the 50 patients. The predominant mutations were TP53 (14.6%), IDH1 (9.7%) and PIK3CA (6.8%). No mutations were detected in 14 (28%) of the 50 patients. IHC demonstrated frequent overexpression of EGFR and mTOR, in 38 (76%) and 35 (70%) patients, respectively. Overexpression of PDGFRa and PDGFRb were less common and detected in 16 and four patients, respectively. For 35 patients a targeted therapy was recommended. In our database, the majority of patients displayed mutations, against which targeted therapy could be offered. Based on our observations, PCM may be a feasible novel treatment approach in neuro-oncology.

Temozolomide has anti-tumor effects through the phosphorylation of cPLA2 on glioblastoma cells

Temozolomide is an alkylating agent used as the first line of treatment for glioblastoma. However, chemoresistance to temozolomide is common in glioma patients. In addition, there are likely many unknown mechanisms for the anti-tumor effects of temozolomide. It is known that an alkylating agent, sulfur mustard, activates cytosolic phospholipase A₂ (cPLA₂) releasing arachidonic acid to suppress tumors. The present study was performed to elucidate the involvement of cPLA₂ in the anti-tumor mechanisms of temozolomide. In three glioblastoma cell lines (GL261, U251MG and T98G), we performed several evaluations including cell viability, cell migration and apoptosis, to study temozolomide-induced anti-tumor effects. Further, we evaluated tumor size in the murine orthotropic glioblastoma model after oral administration of temozolomide. Finally, we investigated the phosphorylation of cPLA₂ in GL261 cells treated with temozolomide, and clarified whether phosphorylation of cPLA₂ affects cell growth. Temozolomide suppressed cell growth and cell migration in glioblastoma cells in vitro and showed anti-tumor effect in the murine orthotopic glioblastoma model in vivo. Furthermore, temozolomide increased phosphorylation of cPLA_2, which was associated with suppression of cell growth. However, in MGMT high-expressing glioblastoma T98G cells, temozolomide could not suppress cell growth or cause phosphorylation of cPLA_2. These findings indicate that temozolomide suppressed cell growth partly by phosphorylation of cPLA₂ in glioblastoma cells. In addition, because temozolomide did not cause phosphorylation of cPLA₂ in MGMT high-expressing glioblastoma T98G cells, phosphorylation of cPLA₂ may be caused by DNA alkylation of temozolomide.

Prognostic Implication of Clinical and Pathologic Features in Patients with Glioblastoma Multiforme Treated with Concomitant Radiation plus Temozolomide

Aims and background

Glioblastoma multiforme is the most common and most malignant primary brain tumor in adults. The current standard of care for glioblastoma is surgical resection to the extent feasible, followed by adjuvant radiotherapy plus temozolomide, given concomitantly with and after radiotherapy. This report is a prospective observational study of 43 cases treated in the Department of Radiotherapy, University of Rome La Sapienza, Italy. We examine the relationship between pathologic features and objective response rate in adult patients treated with concomitant radiation plus temozolomide to identify clinical, neuroradiologic, pathologic, and molecular factors with prognostic significance.

Methods

Forty-three consecutive patients (24 males and 19 females), ages 15-77 years (median, 57) with newly diagnosed glioblastoma multiforme, were included in this trial between 2002 and 2004 at our department. All patients were treated with surgery (complete resection in 81%, incomplete in 19%) followed by concurrent temozolomide (75 mg/m2/day) and radiotherapy (median tumor dose, 60 Gy), followed by temozolomide, 200 mg/m2/day for 5 consecutive days every 28 days. Neurologic evaluations were performed monthly and cranial magnetic resonance bimonthly. We analyzed age, clinical manifestations at diagnosis, seizures, Karnofsky performance score, tumor location, extent of resection, proliferation index (Ki-67 expression), p53, platelet-derived growth factor and epidermal growth factor receptor immunohistochemical expression as prognostic factors in the patients. The Kaplan-Meier statistical method and logrank test were used to assess correlation with survival.

Results

Fourteen patients (32%) manifested clinical and neuroradiographic evidence of tumor progression within 6 months of surgery. In contrast, 5 patients (12%) showed no disease progression for 18 months from the beginning of treatment. Median overall survival was 19 months. Multivariate analysis revealed that an age of 60 years or older (P <0.03), a postoperative performance score ≤70 (P = 0.04), the nontotal tumor resection (P = 0.03), tumor size >4 cm (P = 0.01) and proliferation index overexpression (P = 0.001) were associated with the worst prognosis. p53, PDGF and EGFR overexpression were not significant prognostic factors associated with survival.

Conclusions

The results suggest that analysis of prognostic markers in glioblastoma multiforme is complex. In addition to previously recognized prognostic variables such as age and Karnofsky performance score, tumor size, total resection and proliferation index overexpression were identified as predictors of survival in a series of patients with glioblastoma multiforme.

Therapy for Recurrent High-Grade Gliomas: Results of a Prospective Multicenter Study on Health-Related Quality of Life

OBJECTIVE

To assess the impact of therapy on patients' health-related quality of life (HRQoL) in recurrent high-grade glioma (HGG) in an unselected cohort.

METHODS

In this prospective multicenter study, we analyzed European Organization for Research and Treatment of Cancer Quality of Life core questionnaire and European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Brain Neoplasm module questionnaires of 92 patients within 1 year after diagnosis of tumor recurrence of a HGG and respective treatment. We evaluated the influence of re-radiation, second- and third-line chemotherapies, and number of recurrent surgeries on summary scores for functioning, symptoms, and total score as well as on subscores for functioning and neurologic symptoms using multivariate mixed models and descriptive statistics.

RESULTS

After we adjusted for Karnofsky Performance Score and age, different recurrent therapies did not significantly impact HRQoL. Neither re-radiation nor recurrent surgery significantly influenced HRQoL (total score, P = 0.66; P = 0.64). Patients receiving second-line chemotherapy showed moderately better physical and role functioning as well as less motor dysfunction than patients receiving third-line chemotherapy. When we compared HRQoL after second-line chemotherapies, patients receiving intensified temozolomide dosages demonstrated a moderately better outcome for cognitive functioning and less communication deficits (P = 0.055) than patients treated with bevacizumab. Regarding number of recurrent surgeries, we found stable HRQoL scores until second recurrent surgery, whereas after third recurrent surgery HRQoL decreased.

CONCLUSIONS

Our results from an unselected cohort of recurrent HGGs show that the currently available treatment options have no negative impact on HRQoL. Thus, treatment decisions can be made individually, without fear of jeopardizing HRQoL for better survival. Only, the third recurrent surgery remains a very individual decision even in younger patients with high Karnofsky Performance Score.

Brain tumors - other treatment modalities

Management of tumors of the central nervous system is challenging for clinicians for various reasons, including complex diagnostic procedures, limited penetration of drugs into brain tissue, and the prerequisite to preserve brain function in any case of therapeutic intervention. Therapeutic success is dependent on the efforts, skills, and cooperation of involved specialists and disciplines. Knowledge and ability to apply adequate therapeutic modalities in an interdisciplinary approach in due time are crucial, necessitating coordination of diagnostic procedures and therapeutic interventions by means of multidisciplinary brain tumor boards. In this chapter we present in brief the essential current standards and future perspectives for therapy modalities that complement surgery of brain tumors.

Pilot Study to Explore the Accuracy of Current Prediction Equations in Assessing Energy Needs of Patients with Newly Diagnosed Glioblastoma Multiforme

Glioblastoma multiforme (GBM) is rare, yet it is the most common brain malignancy and has a poor prognosis. In regard to GBM, there is a dearth of research on resting energy expenditure (REE) and the accuracy of extant prediction equations. The aim of this cross-sectional study was to compare measured REE (mREE) to commonly used prediction equations in newly diagnosed GBM patients. REE was collected by indirect calorimetry in 20 GBM patients. Calculated REE was derived from Harris-Benedict (again with weight adjusted for obesity), Mifflin-St Jeor, and the 20 kcal/kg body weight ratio method. Paired t-tests and Bland-Altman analyses were used to compare group means, evaluate the bias, and find the limits of agreement. Clinical accuracy was assessed by determining the percentage of patients with predicted REE within ±10% of mREE. Subjects were evenly distributed with regard to gender, primarily Caucasian, and largely overweight or obese and had a mean age of 57 years. All equations overestimated mREE. Mifflin-St Jeor and adjusted Harris-Benedict had the narrowest limits of agreement and accurately predicted 60% and 65% of subjects, respectively. Clinicians should be aware of the discrepancy between commonly used prediction equations and REE. More research is needed to verify these findings and decipher the cause and significance in the GBM population.

Implementation of computer-based quality-of-life monitoring in brain tumor outpatients in routine clinical practice

CONTEXT

Computerized assessment of quality of life (QOL) in patients with brain tumors can be an essential part of quality assurance with regard to evidence-based medicine in neuro-oncology.

OBJECTIVES

The aim of this project was the implementation of a computer-based QOL monitoring tool in a neurooncology outpatient unit. A further aim was to derive reference values for QOL scores from the collected data to improve interpretability.

METHODS

Since August 2005, patients with brain tumors treated at the neuro-oncology outpatient unit of the Innsbruck Medical University were consecutively included in the study. QOL assessment (European Organisation for Research and Treatment of Cancer [EORTC] Quality of Life Questionnaire [QLQ-C30] plus the EORTC QLQ-brain cancer module [BN20]) was computer-based, using a software tool called the Computer-based Health Evaluation System.

RESULTS

A total of 110 patients with primary brain tumors (49% female; mean [standard deviation] age 47.9 [12.6] years; main diagnoses: 30.9% astrocytoma, 17.3% oligodendroglioma, 17.3% glioblastoma, 13.6% meningioma) was included in the study. On average, QOL was assessed 4.74 times per patient, 521 times in total. The user-friendly software was successfully implemented and tested. The routine QOL assessment was found to be feasible and was well accepted by both physicians and patients.

CONCLUSION

The software-generated graphic QOL profiles were found to be an important tool for screening patients for clinically relevant problems. Thus, computer-based QOL monitoring can contribute to an optimization of treatment (e.g., symptom management, psychosocial interventions) and facilitate data collection for research purposes.

Health-related quality of life in patients with high-grade glioma

Health-related quality of life (HRQOL) has become an increasingly important endpoint in cancer studies; however, the research into the HRQOL of patients with high-grade glioma (HGG) is sparse compared with that for patients with other neoplasms. Owing to the specific location and poor prognosis, it is more important and difficult to study HRQOL in patients with HGG than in those with other tumors; furthermore, the study of HRQOL in patients with HGG differs from that for patients with other tumors. In this review, we identified and compared the most frequently used instruments to assess HRQOL; analyzed specific facets and determinants of HRQOL (such as sex, tumor location and histological classification, depression, and cognitive function), as well as the association between HRQOL and survival; and appraised the effects of new treatments on HRQOL in patients with HGG from randomized controlled trials. Furthermore, we detected broadly existing problems and many contradictory outcomes and gave some proper interpretation and suggestions regarding them.

Salvage chemotherapy with procarbazine and fotemustine combination in the treatment of temozolomide treated recurrent glioblastoma patients

The purpose of this study was to evaluate safety and efficacy of Procarbazine (PCB) and fotemustine (FTM) combination in the treatment of pre-temozolomide treated, recurrent GBM patients. The primary end-point was progression free survival at 6 months (PFS-6). Secondary end-points were overall survival, response rates (CR + PR) and toxicity. About 54 patients (41 men and 13 women) aged 26-68 years (median age, 53.5 years) with recurrent GBM were treated. PCB was administered as an oral dosage of 450 mg on days 1-2 and a total dose of 300 mg on day 3. FTM was administered on day 3, 3 h after the last PCB intake at a dose of 110 mg/mq/BSA. The treatment was repeated every 5 weeks. Treatment was continued for a maximum of six cycles or until disease progression. After two cycles of chemotherapy: 6 patients (11.2%) experienced a neuroradiographic partial response (PR), 29 patients (53.7%) had stable disease (SD), and 19 patients (35.1%) had progressive disease (PD). For the whole group of patients, the median PFS was 19.3 weeks (95% CI, 14.1-24.4 weeks), and PFS-6 was 26.7% (95% CI, 10.6-42.8%). Overall MST from the beginning of PCB + FTM chemotherapy was 28.7 weeks (95% CI, 24.8-32.7 weeks). At 6 and 12 months, 64.4% (95% CI, 51.5-77.3%) and 23.6% (95% CI, 10.1-37.1%) of patients were alive. The median survival time calculated from the first diagnosis was 20.8 months (95% CI, 16.7-24.8). We concluded that the PCB + FTM combination as done in the current trial for patients with recurrent GBM after treatment with TMZ showed some benefit with regards to increased survival and that a Phase III trial is warranted.

Management of glioma in Victoria (1998–2000): retrospective cohort study

OBJECTIVE

To describe the management of and outcomes in a population-based cohort of patients with newly diagnosed glioma.

DESIGN, SETTING AND PATIENTS

Retrospective cohort study of patients with glioma newly diagnosed over the period 1998-2000 in Victoria. Patients were identified from the population-based Victorian Cancer Registry (VCR). Doctors involved in managing the patients were surveyed by a questionnaire sent out in 2003. The cohort was followed until the end of 2004 to obtain at least 4 years' follow-up data on all patients.

MAIN OUTCOME MEASURES

Reported treatment, referral patterns and survival rates.

RESULTS

Over the study period, 992 cases of glioma were identified; 828 completed surveys on eligible patients were obtained (response rate, 93%); 473 patients (57%) had glioblastoma multiforme (GBM); 105 patients (13%) diagnosed with "glioma" had had no histological confirmation. Complete macroscopic resection was performed in 209 patients (25%); 612 patients (74%) were referred for radiotherapy and 326 (54%) for chemotherapy; 39 (5%) were enrolled on a clinical trial. Median survival was 9.2 months for all patients and 7.4 months for patients with GBM.

CONCLUSIONS

This is the largest reported glioma management survey in the world to date. Much of the patient demographics and approach to treatment were as expected and represent a reasonable "standard of care". However, there are some areas for improvement, including the absence of histological diagnosis in some patients, lack of multidisciplinary care, low clinical trial enrollment and poor use of ancillary services.