A phase III randomized prospective trial of external beam radiotherapy, mitomycin C, carmustine, and 6-mercaptopurine for the treatment of adults with anaplastic glioma of the brain. CNS Cancer Consortium

Metabolic models predict fotemustine and the combination of eflornithine/rifamycin and adapalene/cannabidiol for the treatment of gliomas

Gliomas are the most common type of malignant brain tumors, with glioblastoma multiforme (GBM) having a median survival of 15 months due to drug resistance and relapse. The treatment of gliomas relies on surgery, radiotherapy and chemotherapy. Only 12 anti-brain tumor chemotherapies (AntiBCs), mostly alkylating agents, have been approved so far. Glioma subtype-specific metabolic models were reconstructed to simulate metabolite exchanges, in silico knockouts and the prediction of drug and drug combinations for all three subtypes. The simulations were confronted with literature, high-throughput screenings (HTSs), xenograft and clinical trial data to validate the workflow and further prioritize the drug candidates. The three subtype models accurately displayed different degrees of dependencies toward glutamine and glutamate. Furthermore, 33 single drugs, mainly antimetabolites and TXNRD1-inhibitors, as well as 17 drug combinations were predicted as potential candidates for gliomas. Half of these drug candidates have been previously tested in HTSs. Half of the tested drug candidates reduce proliferation in cell lines and two-thirds in xenografts. Most combinations were predicted to be efficient for all three glioma types. However, eflornithine/rifamycin and cannabidiol/adapalene were predicted specifically for GBM and low-grade glioma, respectively. Most drug candidates had comparable efficiency in preclinical tests, cerebrospinal fluid bioavailability and mode-of-action to AntiBCs. However, fotemustine and valganciclovir alone and eflornithine and celecoxib in combination with AntiBCs improved the survival compared to AntiBCs in two-arms, phase I/II and higher glioma clinical trials. Our work highlights the potential of metabolic modeling in advancing glioma drug discovery, which accurately predicted metabolic vulnerabilities, repurposable drugs and combinations for the glioma subtypes.

Epigenetic Mechanisms of Aging and Aging-Associated Diseases

Aging is an inevitable outcome of life, characterized by a progressive decline in tissue and organ function. At a molecular level, it is marked by the gradual alterations of biomolecules. Indeed, important changes are observed on the DNA, as well as at a protein level, that are influenced by both genetic and environmental parameters. These molecular changes directly contribute to the development or progression of several human pathologies, including cancer, diabetes, osteoporosis, neurodegenerative disorders and others aging-related diseases. Additionally, they increase the risk of mortality. Therefore, deciphering the hallmarks of aging represents a possibility for identifying potential druggable targets to attenuate the aging process, and then the age-related comorbidities. Given the link between aging, genetic, and epigenetic alterations, and given the reversible nature of epigenetic mechanisms, the precisely understanding of these factors may provide a potential therapeutic approach for age-related decline and disease. In this review, we center on epigenetic regulatory mechanisms and their aging-associated changes, highlighting their inferences in age-associated diseases.

Treatment of newly diagnosed glioblastoma in the elderly: a network meta-analysis

BACKGROUND

A glioblastoma is a fatal type of brain tumour for which the standard of care is maximum surgical resection followed by chemoradiotherapy, when possible. Age is an important consideration in this disease, as older age is associated with shorter survival and a higher risk of treatment-related toxicity.

OBJECTIVES

To determine the most effective and best-tolerated approaches for the treatment of elderly people with newly diagnosed glioblastoma. To summarise current evidence for the incremental resource use, utilities, costs and cost-effectiveness associated with these approaches.

SEARCH METHODS

We searched electronic databases including the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and Embase to 3 April 2019, and the NHS Economic Evaluation Database (EED) up to database closure. We handsearched clinical trial registries and selected neuro-oncology society conference proceedings from the past five years.

SELECTION CRITERIA

Randomised trials (RCTs) of treatments for glioblastoma in elderly people. We defined 'elderly' as 70+ years but included studies defining 'elderly' as over 65+ years if so reported.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods for study selection and data extraction. Where sufficient data were available, treatment options were compared in a network meta-analysis (NMA) using Stata software (version 15.1). For outcomes with insufficient data for NMA, pairwise meta-analysis were conducted in RevMan. The GRADE approach was used to grade the evidence.

MAIN RESULTS

We included 12 RCTs involving approximately 1818 participants. Six were conducted exclusively among elderly people (either defined as 65 years or older or 70 years or older) with newly diagnosed glioblastoma, the other six reported data for an elderly subgroup among a broader age range of participants. Most participants were capable of self-care. Study quality was commonly undermined by lack of outcome assessor blinding and attrition. NMA was only possible for overall survival; other analyses were pair-wise meta-analyses or narrative syntheses. Seven trials contributed to the NMA for overall survival, with interventions including supportive care only (one trial arm); hypofractionated radiotherapy (RT40; four trial arms); standard radiotherapy (RT60; five trial arms); temozolomide (TMZ; three trial arms); chemoradiotherapy (CRT; three trial arms); bevacizumab with chemoradiotherapy (BEV_CRT; one trial arm); and bevacizumab with radiotherapy (BEV_RT). Compared with supportive care only, NMA evidence suggested that all treatments apart from BEV_RT prolonged survival to some extent. Overall survival High-certainty evidence shows that CRT prolongs overall survival (OS) compared with RT40 (hazard ratio (HR) 0.67, 95% confidence interval (CI) 0.56 to 0.80) and low-certainty evidence suggests that CRT may prolong overall survival compared with TMZ (TMZ versus CRT: HR 1.42, 95% CI 1.01 to 1.98). Low-certainty evidence also suggests that adding BEV to CRT may make little or no difference (BEV_CRT versus CRT: HR 0.83, 95% CrI 0.48 to 1.44). We could not compare the survival effects of CRT with different radiotherapy fractionation schedules (60 Gy/30 fractions and 40 Gy/15 fractions) due to a lack of data. When treatments were ranked according to their effects on OS, CRT ranked higher than TMZ, RT and supportive care only, with the latter ranked last. BEV plus RT was the only treatment for which there was no clear benefit in OS over supportive care only.   One trial comparing tumour treating fields (TTF) plus adjuvant chemotherapy (TTF_AC) with adjuvant chemotherapy alone could not be included in the NMA as participants were randomised after receiving concomitant chemoradiotherapy, not before. Findings from the trial suggest that the intervention probably improves overall survival in this selected patient population. We were unable to perform NMA for other outcomes due to insufficient data. Pairwise analyses were conducted for the following. Quality of life Moderate-certainty narrative evidence suggests that overall, there may be little difference in QoL between TMZ and RT, except for discomfort from communication deficits, which are probably more common with RT (1 study, 306 participants, P = 0.002). Data on QoL for other comparisons were sparse, partly due to high dropout rates, and the certainty of the evidence tended to be low or very low. Progression-free survival High-certainty evidence shows that CRT increases time to disease progression compared with RT40 (HR 0.50, 95% CI 0.41 to 0.61); moderate-certainty evidence suggests that RT60 probably increases time to disease progression compared with supportive care only (HR 0.28, 95% CI 0.17 to 0.46), and that BEV_RT probably increases time to disease progression compared with RT40 alone (HR 0.46, 95% CI 0.27 to 0.78). Evidence for other treatment comparisons was of low- or very low-certainty. Severe adverse events Moderate-certainty evidence suggests that TMZ probably increases the risk of grade 3+ thromboembolic events compared with RT60 (risk ratio (RR) 2.74, 95% CI 1.26 to 5.94; participants = 373; studies = 1) and also the risk of grade 3+ neutropenia, lymphopenia, and thrombocytopenia. Moderate-certainty evidence also suggests that CRT probably increases the risk of grade 3+ neutropenia, leucopenia and thrombocytopenia compared with hypofractionated RT alone. Adding BEV to CRT probably increases the risk of thromboembolism (RR 16.63, 95% CI 1.00 to 275.42; moderate-certainty evidence). Economic evidence There is a paucity of economic evidence regarding the management of newly diagnosed glioblastoma in the elderly. Only one economic evaluation on two short course radiotherapy regimen (25 Gy versus 40 Gy) was identified and its findings were considered unreliable.

AUTHORS' CONCLUSIONS

For elderly people with glioblastoma who are self-caring, evidence suggests that CRT prolongs survival compared with RT and may prolong overall survival compared with TMZ alone. For those undergoing RT or TMZ therapy, there is probably little difference in QoL overall. Systemic anti-cancer treatments TMZ and BEV carry a higher risk of severe haematological and thromboembolic events and CRT is probably associated with a higher risk of these events. Current evidence provides little justification for using BEV in elderly patients outside a clinical trial setting. Whilst the novel TTF device appears promising, evidence on QoL and tolerability is needed in an elderly population. QoL and economic assessments of CRT versus TMZ and RT are needed. More high-quality economic evaluations are needed, in which a broader scope of costs (both direct and indirect) and outcomes should be included.

Constitutional mismatch repair-deficiency: current problems and emerging therapeutic strategies

Mismatch repair (MMR) proteins remove errors from newly synthesized DNA, improving the fidelity of DNA replication. A loss of MMR causes a mutated phenotype leading to a predisposition to cancer. In the last 20 years, an increasing number of patients have been described with biallelic MMR gene mutations in which MMR defects are inherited from both parents. This leads to a syndrome with recessive inheritance, referred to as constitutional mismatch repair-deficiency (CMMRD). CMMRD is a rare childhood cancer predisposition syndrome. The spectrum of CMMRD tumours is broad and CMMRD-patients possess a high risk of multiple cancers including hematological, brain and intestinal tumors. The severity of CMMRD is highlighted by the fact that patients do not survive until later life, emphasising the requirement for new therapeutic interventions. Many tumors in CMMRD-patients are hypermutated leading to the production of truncated protein products termed neoantigens. Neoantigens are recognized as foreign by the immune system and induce antitumor immune responses. There is growing evidence to support the clinical efficacy of neoantigen based vaccines and immune checkpoint inhibitors (collectively referred to as immunotherapy) for the treatment of CMMRD cancers. In this review, we discuss the current knowledge of CMMRD, the advances in its diagnosis, and the emerging therapeutic strategies for CMMRD-cancers.

Review of Current Protocols for Protontherapy in USA

The basis for interest in proton beams by clinical radiation oncologists lies in reduction in treatment volume. The yields from employing a smaller treatment volume are the increase of tumor control probability and the reduction of normal tissues complication probability. The clinical use of proton therapy began in 1954 at Uppsala University in Sweden and in 1961 at Harvard Cyclotron Laboratory in Boston, USA. So far, the total number of worldwide patients treated by protons is about 20,000. In this paper attention will be given to the treatment of patients at the Massachusetts General Hospital-Massachusetts Eye and Ear Infirmary-Harvard Cyclotron Laboratory, and at the Loma Linda University Medical Center. In particular, a review of the literature about the techniques and the results of treatment of skull base and cervical spine chordoma and low-grade chondrosarcoma, skull base meningioma, pituitary tumors, paranasal sinus carcinoma, glioblastoma multiforme, artero-venous malformations, uveal melanoma, macular degeneration, retinoblastoma, thoracic spine-sacrum tumors, and prostate carcinoma is presented. In order to verify and improve the clinical results, the conduct of prospective trials on an inter-institutional basis is essential. To facilitate the conduct of such studies the US National Cancer Institute and the American College of Radiology have established the Proton Therapy Oncology Group (PROG). Several phase III and some phase I-II trials are active at the Massachusetts General Hospital, Harvard Cyclotron Laboratory, and at the Loma Linda University Medical Center.

Patterns of care and outcomes in gliosarcoma: an analysis of the National Cancer Database

OBJECTIVE The authors compared presenting characteristics and survival for patients with gliosarcoma (GS) and glioblastoma (GBM). Additionally, they performed a survival analysis for patients who underwent GS treatments with the hypothesis that trimodality therapy (surgery followed by radiation and chemotherapy) would be superior to nontrimodality therapy (surgery alone or surgery followed by chemotherapy or radiation). METHODS Adults diagnosed with GS and GBM between the years 2004 and 2013 were queried from the National Cancer Database. Chi-square analysis was used to compare presenting characteristics. Kaplan-Meier, Cox regression, and propensity score analyses were employed for survival analyses. RESULTS In total, data from 1102 patients with GS and 36,658 patients with GBM were analyzed. Gliosarcoma had an increased rate of gross-total resection (GTR) compared with GBM (19% vs 15%, p < 0.001). Survival was not different for patients with GBM (p = 0.068) compared with those with GS. After propensity score analysis for GS, patients receiving trimodality therapy (surgery followed by radiation and chemotherapy) had improved survival (12.9 months) compared with those not receiving trimodality therapy (5.5 months). In multivariate analysis, GTR, female sex, fewer comorbidities, trimodality therapy, and age < 65 years were associated with improved survival. There was a trend toward improved survival with MGMT promoter methylation (p = 0.117). CONCLUSIONS In this large registry study, there was no difference in survival in patients with GBM compared with GS. Among GS patients, trimodality therapy significantly improved survival compared with nontrimodality therapy. Gross-total resection also improved survival, and there was a trend toward increased survival with MGMT promoter methylation in GS. The major potential confounder in this study is that patients with poor functional status may not have received aggressive radiation or chemotherapy treatments, leading to the observed outcome. This study should be considered hypothesis-generating; however, due to its rarity, conducting a clinical trial with GS patients alone may prove difficult.

An update on the epigenetics of glioblastomas

Glioblastomas, also known as glioblastoma multiforme (GBM), are the most aggressive and malignant type of primary brain tumor in adults, exhibiting notable variability at the histopathological, genetic and epigenetic levels. Recently, epigenetic alterations have emerged as a common hallmark of many tumors, including GBM. Considering that a deeper understanding of the epigenetic modifications that occur in GBM may increase the knowledge regarding the tumorigenesis, progression and recurrence of this disease, in this review we discuss the recent major advances in GBM epigenetics research involving histone modification, glioblastoma stem cells, DNA methylation, noncoding RNAs expression, including their main alterations and the use of epigenetic therapy as a valid option for GBM treatment.

Radioresistance of Brain Tumors

Radiation therapy (RT) is frequently used as part of the standard of care treatment of the majority of brain tumors. The efficacy of RT is limited by radioresistance and by normal tissue radiation tolerance. This is highlighted in pediatric brain tumors where the use of radiation is limited by the excessive toxicity to the developing brain. For these reasons, radiosensitization of tumor cells would be beneficial. In this review, we focus on radioresistance mechanisms intrinsic to tumor cells. We also evaluate existing approaches to induce radiosensitization and explore future avenues of investigation.

Therapeutic management of gliosarcoma in the temozolomide era

Gliosarcoma (GS) is a malignant, uncommon variant of high-grade glioma comprised of infiltrative glial and atypical sarcomatous cells, identified in adult and pediatric populations. GS has been subcategorized into primary (de novo) and secondary tumors, with the latter typically arising in the setting of prior glioblastoma. Due to its rarity, the pathogenesis, epidemiology and optimal therapy of GS have been based on small retrospective cohort studies, with treatment presently utilizing regimens established for other high-grade gliomas, including combination of resection, radiotherapy and temozolomide-based chemotherapy. As more information is gathered about GS molecular profiles, novel treatment strategies may be developed to improve outcomes of GS patients. Here we summarize results of GS management with focus on the temozolomide era.

Age-specific signatures of glioblastoma at the genomic, genetic, and epigenetic levels

Age is a powerful predictor of survival in glioblastoma multiforme (GBM) yet the biological basis for the difference in clinical outcome is mostly unknown. Discovering genes and pathways that would explain age-specific survival difference could generate opportunities for novel therapeutics for GBM. Here we have integrated gene expression, exon expression, microRNA expression, copy number alteration, SNP, whole exome sequence, and DNA methylation data sets of a cohort of GBM patients in The Cancer Genome Atlas (TCGA) project to discover age-specific signatures at the transcriptional, genetic, and epigenetic levels and validated our findings on the REMBRANDT data set. We found major age-specific signatures at all levels including age-specific hypermethylation in polycomb group protein target genes and the upregulation of angiogenesis-related genes in older GBMs. These age-specific differences in GBM, which are independent of molecular subtypes, may in part explain the preferential effects of anti-angiogenic agents in older GBM and pave the way to a better understanding of the unique biology and clinical behavior of older versus younger GBMs.

Safety and efficacy of a novel cannabinoid chemotherapeutic, KM-233, for the treatment of high-grade glioma

OBJECTIVE

To test in vitro and in vivo the safety and efficacy of a novel chemotherapeutic agent, KM-233, for the treatment of glioma.

METHODS

In vitro cell cytotoxicity assays were used to measure and compare the cytotoxic effects of KM-233, Delta(8)-tetrahydrocannabinol (THC), and bis-chloroethyl-nitrosurea (BCNU) against human U87 glioma cells. An organotypic brain slice culture model was used for safety and toxicity studies. A human glioma-SCID mouse side-pocket tumor model was used to test in vivo the safety and efficacy of KM-233 with intratumoral and intra-peritoneal administration.

RESULTS

KM-233 is a classical cannabinoid with good blood brain barrier penetration that possesses a selective affinity for the CB2 receptors relative to THC. KM-233 was as efficacious in its cytotoxicity against human U87 glioma as Delta(8)-tetrahydrocannabinol, and superior to the commonly used anti-glioma chemotherapeutic agent, BCNU. The cytotoxic effects of KM-233 against human glioma cells in vitro occur as early as two hours after administration, and dosing of KM-233 can be cycled without compromising cytotoxic efficacy and while improving safety. Cyclical dosing of KM-233 to treat U87 glioma in a SCID mouse xenograft side pocket model was effective at reducing the tumor burden with both systemic and intratumoral administration.

CONCLUSION

These studies provide both in vitro and in vivo evidence that KM-233 shows promising efficacy against human glioma cell lines in both in vitro and in vivo studies, minimal toxicity to healthy cultured brain tissue, and should be considered for definitive preclinical development in animal models of glioma.

Is the long-term survival of patients with intracranial glioblastoma multiforme overstated?

BACKGROUND

The 5-year survival rate for intracranial glioblastoma multiforme (GBM) has remained at 4-5% for the last 30 years, in spite of multiple randomized prospective trials. The authors hypothesized, based on the literature, that even this remarkably poor survival rate is an overstatement. They investigated this hypothesis using the the Duke University Medical Center Tumor Registry.

METHODS

The authors reviewed all patients with the diagnosis of intracranial GBM recorded in the Duke University Medical Center Tumor Registry from the registry's inception in 1976 through 1996. This search identified a population of patients with a minimum of 5 years of follow-up. Each of the long-term survivors was assigned a code number for clinical information. The pathology slides were provided to a neuropathologist in a coded fashion so that the patients could not be identified. The neuropathologist reviewed the slides to analyze the presence or absence of nine histologic factors. A match technique was used to identify a control population of patients with GBM who were not 5-year survivors and were all deceased. The control population was compared with the study population to ascertain if there are histologic correlates associated with long-term survivorship.

RESULTS

The authors identified 766 patients recorded by the tumor registry as having an intracranial GBM with a minimum of 5 years of follow up. Of the total population, 32 patients initially appeared to be 5-year survivors (4%). Upon review of the medical records for these 32 patients, however, the authors found only 17 patients who were truly 5-year survivors. The most common reason for miscoding was the presence of a low-grade astrocytoma that subsequently dedifferentiated into GBM. The 17 long-term survivors included 11 males and 6 females. Their mean age at diagnosis was 40.2 years. Therapy consisted of a macroscopic total resection in 4 patients (22%), a biopsy in 1 patient (6%), a subtotal resection in 10 patients (56%), and unknown extent of resection in 2 patients (11%). All patients received partial brain irradiation (mean dose, 62.6 Gy) and chemotherapy. Thirteen different single-agent or combination chemotherapy programs were used. Two patients also received I-131 monoclonal antibody therapy. Analysis of the nine histopathologic factors studied showed that intermediate fibrillary elements were more common and small anaplastic elements were less common in the long-term survivors than in the control population.

CONCLUSIONS

Survival data on intracranial GBM, based on tumor registry data, should be interpreted cautiously. Reliable conclusions can only be drawn when such data are supplemented with clinical information and the histopathology is reviewed carefully. The group of long-term survivors in the current study were younger than the typical GBM population. Conventionally treated patients with GBM, chosen from an unselected population from a tumor registry, have a smaller chance of long-term survival than is generally believed.

Prospective study of neuropsychologic testing and quality-of-life assessment of adults with primary malignant brain tumors

PURPOSE

To identify the characteristics of adult patients with newly diagnosed primary brain tumors associated with identifiable deficits in neuropsychologic function to target interventions to improve function and quality of life (QOL).

MATERIALS AND METHODS

Adult patients with newly diagnosed primary brain tumors and their caregivers were enrolled and underwent a battery of standardized neuropsychologic tests, allowing for qualitative and quantitative assessment and sensitive to the effects of the brain tumor, QOL, or caregiver stress.

RESULTS

We enrolled 68 patients with no prior radiotherapy. Patients with left hemisphere tumors reported significantly more memory problems and depressive symptoms. They also exhibited poorer attention and were more distractible, with poorer verbal fluency and poorer verbal learning. Patients with glioblastoma multiforme demonstrated poorer psychomotor speed and visual tracking than patients with non-glioblastoma multiforme histologic features. Patients and caregivers perceived QOL in a similar fashion, with significant correlation between patient and caregiver on hope testing and general QOL on the Linear Analog Self-Assessment Scale.

CONCLUSIONS

Patients with left hemisphere tumors and glioblastoma multiforme histologic features demonstrated testable differences in neuropsychologic function and QOL that may be amenable to improvement with medical therapy or tailored rehabilitation programs. Caregiver assessments can predict patient QOL, which may be useful in patients with declining status.

Importance of hypoxia in the biology and treatment of brain tumors

The resistance of gliomas to treatment with radiation and antineoplastic drugs may result in part from the effects of the extensive, severe hypoxia that is present in these tumors. It is clear that brain tumors contain extensive regions in which the tumor cells are subjected to unphysiological levels of hypoxia. Hypoxic cells are resistant to radiation. Hypoxia and the perfusion deficits and metabolic changes that accompany hypoxia in vivo also produce resistance to many commonly used anticancer drugs. The resistance of cells that are hypoxic at the time of therapy may influence the efficacy of the treatment of these tumors with radiation, chemotherapy, and combined modality regimens. Moreover, it is becoming increasingly evident from laboratory studies that exposure of cells to adverse microenvironments produces transient changes in gene expression, induces mutations, and selects for cells with altered genotypes, thus driving the evolution of the cell population toward increasing malignancy and increasingly aggressive phenotypes. Hypoxia may therefore be involved in the evolution of cells in low-grade malignancies to the resistant, aggressive phenotype characteristic of glioblastomas. During the past 50 years, many attempts have been made to circumvent the therapeutic resistance induced by hypoxia, by improving tumor oxygenation, by using oxygen-mimetic radiosensitizers, by adjuvant therapy with drugs that are preferentially toxic to hypoxic cells, by using hyperthermia, or by devising radiation sources and regimens that are less affected by hypoxia. Past clinical trials have provided tantalizing suggestions that the outcome of therapy can be improved by many of these approaches, but none has yet produced a significant, reproducible improvement in the therapeutic ratio, which would be needed for any of these approaches to become the standard therapy for these diseases. Several ongoing clinical trials are addressing other, hopefully better regimens; it will be interesting to see the results of these studies.

Novel chemotherapeutic approaches to brain tumors

In reviewing the numerous investigational drug trials for patients with anaplastic gliomas over the past 20 years, it would be fair to say that there have been more than a few disappointments and that the real impact of many of these therapies on patients' duration and quality of survival has been minor at best. It is also fair to state that there has been progress in developing new types of chemotherapy and other agents, in devising new treatment strategies, and in gaining a deeper understanding of the problems that must be overcome to treat patients with anaplastic gliomas successfully. The past several years have seen the realization that oligodendroglioma, primary CNS lymphoma, and medulloblastoma are sensitive to chemotherapy treatments. It is hoped that future studies will delineate better the optimal use of chemotherapy for these tumors.

Multidisciplinary management of adult anaplastic astrocytomas

The management of patients with anaplastic astrocytoma (AA) requires multidisciplinary involvement. In this article, the literature on the treatment of patients with AA is reviewed, emphasizing randomized trials and key retrospective studies. The role of surgery, radiation therapy, and chemotherapy in newly diagnosed patients and those with recurrent disease is described. Basic science insights, advances in neuroimaging and neuropathology, and novel therapies targeting invasion, angiogenesis, and growth modulation will hopefully lead to improved outcome in this subset of patients with malignant glioma.

The conditional survival statistics for survivors with primary supratentorial astrocytic tumors

BACKGROUND

Relative survival rates can offer a general description of tumor outcome and, traditionally, are used for surveillance and comparison purposes. However, they are not informative for individual tumor survivors. Conditional survival estimates can calculate the probability of surviving next some years given survival to a specific period of time after craniotomy for individual tumor survivors. However, clinically, they have not been used for predicting the tumor outcome.

METHODS

We calculated conditional probabilities of survival within 6 years after craniotomy in 112 patients with primary supratentorial astrocytic tumors and evaluated factors affecting the survival time more than 2 years after craniotomy.

RESULTS

Our data showed that the conditional probability of survival can predict yearly survival rate when patients survive for a specific period of time. The conditional survival rates within 6 years after craniotomy were always higher than those evaluated by relative survival rates. Overall, the longer the patients survived, the higher the conditional probabilities of surviving sixth year postoperatively were.

CONCLUSION

Our study demonstrates the conditional probabilities of survival have good availability and are important estimates for individual tumor survivors.

Radiotherapy of glioblastoma multiforme. Feasibility of increased fraction size and shortened overall treatment

PURPOSE

With regard to the poor prognosis of patients with glioblastoma multiforme, the aspect of life quality with a minimal treatment time becomes essential. The purpose of the present study is to evaluate whether the results of a radiotherapy schedule using increased single fractions applied over a shortened treatment time is feasible without compromising treatment efficiency or providing more side effects than a conventionally fractionated treatment.

PATIENTS AND METHODS

A total of 38 patients (f = 21, m = 17, mean age 58 years) with histologically proven glioblastoma multiforme were irradiated after (partial) resection (n = 29) or stereotactic surgery (n = 9) with single doses of 3.5 Gy (ICRU) 5 fractions a week up to a total dose of 42 Gy following individual treatment planning.

RESULTS

Median survival was 45.7 weeks, survival rate after 6 months was 80.9% and decreased to 34.2% after 12 months. Radiotherapy was tolerated without any important acute toxicity or any late side effects during the follow-up period.

CONCLUSIONS

The increase of the dose per fraction using a fraction size of 3.5 Gy enhanced neither acute nor late toxicity. The survival rate compared well to those described in the literature. Thus the shortened treatment schedule seems as efficient as conventional radiotherapy. Moreover, it seems preferable with regard to quality of life.

[Concomitant chemoradiotherapy and malignant glial tumors in the adult]

The prognosis of adult patients with malignant gliomas remains poor despite advances in neurosurgery and radiotherapy. Even if chemotherapy has done little to improve on these results, except in the treatment of oligodendrogliomas, many authors have proposed to test the effect of radiotherapy by adding concomitant chemotherapy. Unfortunately, the analysis of these studies is difficult because all these protocols are different with a small number of patients. Furthermore, there are only a few studies evaluated in well controlled clinical trials with homogeneous patient population. Important factors such as tumor grade, patient age, and Karnofsky score, which have a strong influence on survival in malignant gliomas, are not clearly evaluated. Whatever, all these studies suggest that concomitant radio-chemotherapy seems not be promising in the treatment of malignant gliomas.

Bihemispheric malignant glioma: one size does not fit all

Recurrence of malignant glioma following radiotherapy most commonly occurs in close proximity to the original contrast enhancing CT/MRI tumor volume. For this reason current radiation planning favors focal radiotherapy fields designed to cover the preoperative tumor contrast enhancing volume +/- surrounding edema with a 2-4 centimetre margin. Two patients with bifrontal malignant gliomas treated with such radiotherapy fields experienced out of field tumor progression while on treatment. Posterior extension along the corpus callosum, not evident on pretreatment imaging, was hypothesized as the cause of the geographic miss. The literature documenting recurrence patterns of malignant glioma following radiotherapy support focal field radiotherapy fields for most patients with malignant glioma. Reporting bias may exist in the literature, however, due to the whole brain radiotherapy used in older series reporting recurrence patterns and exclusion of patients with bihemispheric or more locally extensive tumors in more modern series. Tumor location and pattern of growth at presentation may be important factors in predicting patterns of spread and relapse after radiotherapy.

Survival and functional status after resection of recurrent glioblastoma multiforme

OBJECTIVE

To determine the selection factors for and results of second resections performed to treat recurrent glioblastoma multiforme (GM), we studied 301 patients with GM who were treated from the time of diagnosis using two prospective clinical protocols.

METHODS

The patients were prospectively followed from the time of diagnosis, using clinical and radiographic criteria after maximal surgical resection and external beam radiotherapy with or without adjuvant chemotherapy. Resection of recurrent GM was performed at the recommendation of the treating clinicians. The results of the second resections were retrospectively reviewed and analyzed using multivariate logistic regression, Kaplan-Meier-Turnbull survival analysis, Cox regression, and propensity score stratification.

RESULTS

Forty-six patients underwent second resections during the study period. The actuarial rate of the second resections was 15% of the patients 1 year after diagnosis and 31% 2 years after diagnosis. Younger age (P = 0.01) and more extensive initial resection (P = 0.02), but not Karnofsky Performance Scale (KPS) score at the time of diagnosis or recurrence, predicted a higher chance of selection for reoperation after initial tumor recurrence. Twenty-eight percent of the patients had improved KPS scores after undergoing reoperation, 49% were stable, and 23% had declines in KPS scores of 10 to 30 points. There was no operative mortality. After reoperation, 85% of the patients received chemotherapy, 11% received brachytherapy or underwent stereotactic radiosurgery, and 17% underwent third resections. The median survival period after reoperation was 36 weeks. Higher preoperative KPS scores predicted longer survival periods after reoperation (P = 0.03). Age and interval since diagnosis were not significant prognostic factors. The median high-quality survival period (KPS score, > or =70) was 18 weeks. The median survival period after first tumor progression was 23 weeks for 130 patients treated using the same protocols who did not undergo reoperations. Patients who did undergo reoperations experienced clinically and statistically significantly longer survival periods. However, this was determined to be partially because of selection bias.

CONCLUSION

Survival after resection of recurrent GM remains poor despite advances in imaging, operative technique, and adjuvant therapies. High-quality survival after resection of recurrence to treat GM seems to have increased significantly since an earlier report from our institution.

Particle beam therapy (hadrontherapy): basis for interest and clinical experience

The particle or hadron beams deployed in radiotherapy (protons, neutrons and helium, carbon, oxygen and neon ions) have physical and radiobiological characteristics which differ from those of conventional radiotherapy beams (photons) and which offer a number of theoretical advantages over conventional radiotherapy. After briefly describing the properties of hadron beams in comparison to photons, this review discusses the indications for hadrontherapy and analyses accumulated experience on the use of this modality to treat mainly neoplastic lesions, as published by the relatively few hadrontherapy centres operating around the world. The analysis indicates that for selected patients and tumours (particularly uveal melanomas and base of skull/spinal chordomas and chondrosarcomas), hadrontherapy produces greater disease-free survival. The advantages of hadrontherapy are most promisingly realised when used in conjunction with modern patient positioning, radiation delivery and focusing techniques (e.g. on-line imaging, three-dimensional conformal radiotherapy) developed to improve the efficacy of photon therapy. Although the construction and running costs of hadrontherapy units are considerably greater than those of conventional facilities, a comprehensive analysis that considers all the costs, particularly those resulting from the failure of less effective conventional radiotherapy, might indicate that hadrontherapy could be cost effective. In conclusion, the growing interest in this form of treatment seems to be fully justified by the results obtained to date, although more efficacy and dosing studies are required.

Quantitative imaging study of extent of surgical resection and prognosis of malignant astrocytomas

OBJECTIVE

This study used quantitative radiological imaging to determine the effect of surgical resection on postoperative survival of patients with malignant astrocytomas. Previous studies relied on the surgeons' impressions of the amount of tumor removed, which is a less reliable measure of the extent of resection.

METHODS

Information concerning possible prognostic factors was collected for 75 patients undergoing magnetic resonance imaging or computed tomography preoperatively and within 10 days postoperatively. Image analysis of the neuroradiological studies was conducted to quantify pre- and postoperative total tumor volumes and enhancing volumes. Univariate and multivariate proportional hazards models were used to analyze the regression of survival regarding 22 covariates that might affect survival. The covariates that were entered included age, gender, tumor grade, cumulative radiation dose, chemotherapy, seizures as a first symptom, Karnofsky performance status at presentation, pre- and postoperative total and enhancing tumor volumes, ratio of pre- to postoperative total and enhancing tumor volumes, tumor location, surgeon's impression of the degree of resection, and subsequent surgery.

RESULTS

There were 23 patients with anaplastic astrocytomas and 52 with glioblastomas multiforme. The estimated mean survival time was 27 months for patients undergoing gross total resection, 33 months for subtotal resection, and 13 months for open or stereotactic biopsy. Five factors that were significant predictors of survival in multivariate analysis were tumor grade, age, Karnofsky performance status, radiation dose, and postoperative complications (P < 0.05). In univariate analysis, tumor grade, radiation dose, age, Karnofsky status, complications, presence of enhancing tumor in postoperative imaging, and postoperative volume of enhancing tumor were significantly associated with survival (P < 0.05).

CONCLUSION

We conclude that the most important prognostic factors affecting survival of patients with anaplastic astrocytomas and glioblastomas multiforme are tumor grade, age, preoperative performance status, and radiation therapy. Postoperative complications adversely affect survival. Aggressive surgical resection did not impart a significant increase in survival time. Surgical resection may improve survival, but its importance is less than that of other factors and may be demonstrable only by larger studies.