NOA-04 randomized phase III trial of sequential radiochemotherapy of anaplastic glioma with procarbazine, lomustine, and vincristine or temozolomide

PURPOSE

The standard of care for anaplastic gliomas is surgery followed by radiotherapy. The NOA-04 phase III trial compared efficacy and safety of radiotherapy followed by chemotherapy at progression with the reverse sequence in patients with newly diagnosed anaplastic gliomas.

PATIENTS AND METHODS

Patients (N = 318) were randomly assigned 2:1:1 (A:B1:B2) to receive conventional radiotherapy (arm A); procarbazine, lomustine (CCNU), and vincristine (PCV; arm B1); or temozolomide (arm B2) at diagnosis. At occurrence of unacceptable toxicity or disease progression, patients in arm A were treated with PCV or temozolomide (1:1 random assignment), whereas patients in arms B1 or B2 received radiotherapy. The primary end point was time to treatment failure (TTF), defined as progression after radiotherapy and one chemotherapy in either sequence.

RESULTS

Patient characteristics in the intention-to-treat population (n = 274) were balanced between arms. All histologic diagnoses were centrally confirmed. Median TTF (hazard ratio [HR] = 1.2; 95% CI, 0.8 to 1.8), progression-free survival (PFS; HR = 1.0; 95% CI, 0.7 to 1.3, and overall survival (HR = 1.2; 95% CI, 0.8 to 1.9) were similar for arms A and B1/B2. Extent of resection was an important prognosticator. Anaplastic oligodendrogliomas and oligoastrocytomas share the same, better prognosis than anaplastic astrocytomas. Hypermethylation of the O(6)-methylguanine DNA-methyltransferase (MGMT) promoter (HR = 0.59; 95% CI, 0.36 to 1.0), mutations of the isocitrate dehydrogenase (IDH1) gene (HR = 0.48; 95% CI, 0.29 to 0.77), and oligodendroglial histology (HR = 0.33; 95% CI, 0.2 to 0.55) reduced the risk of progression. Hypermethylation of the MGMT promoter was associated with prolonged PFS in the chemotherapy and radiotherapy arm.

CONCLUSION

Initial radiotherapy or chemotherapy achieved comparable results in patients with anaplastic gliomas. IDH1 mutations are a novel positive prognostic factor in anaplastic gliomas, with a favorable impact stronger than that of 1p/19q codeletion or MGMT promoter methylation.

Effect of pimobendan or benazepril hydrochloride on survival times in dogs with congestive heart failure caused by naturally occurring myxomatous mitral valve disease: the QUEST study

BACKGROUND

Myxomatous mitral valve disease (MMVD) continues to be an important cause of morbidity and mortality in geriatric dogs despite conventional therapy.

HYPOTHESIS

Pimobendan in addition to conventional therapy will extend time to sudden cardiac death, euthanasia for cardiac reasons, or treatment failure when compared with conventional therapy plus benazepril in dogs with congestive heart failure (CHF) attributable to MMVD.

ANIMALS

Two hundred and sixty client-owned dogs in CHF caused by MMVD were recruited from 28 centers in Europe, Canada, and Australia.

METHODS

A prospective single-blinded study with dogs randomized to PO receive pimobendan (0.4-0.6 mg/kg/d) or benazepril hydrochloride (0.25-1.0 mg/kg/d). The primary endpoint was a composite of cardiac death, euthanized for heart failure, or treatment failure.

RESULTS

Eight dogs were excluded from analysis. One hundred and twenty-four dogs were randomized to pimobendan and 128 to benazepril. One hundred and ninety dogs reached the primary endpoint; the median time was 188 days (267 days for pimobendan, 140 days for benazepril hazard ratio = 0.688, 95% confidence limits [CL]=0.516-0.916, P= .0099). The benefit of pimobendan persisted after adjusting for all baseline variables. A longer time to reach the endpoint was also associated with being a Cavalier King Charles Spaniel, requiring a lower furosemide dose, and having a higher creatinine concentration. Increases in several indicators of cardiac enlargement (left atrial to aortic root ratio, vertebral heart scale, and percentage increase in left ventricular internal diameter in systole) were associated with a shorter time to endpoint, as was a worse tolerance for exercise.

CONCLUSIONS AND CLINICAL IMPORTANCE

Pimobendan plus conventional therapy prolongs time to sudden death, euthanasia for cardiac reasons, or treatment failure in dogs with CHF caused by MMVD compared with benazepril plus conventional therapy.

Diagnosis of pseudoprogression in patients with glioblastoma using O-(2-[18F]fluoroethyl)-L-tyrosine PET

PURPOSE

The follow-up of glioblastoma patients after radiochemotherapy with conventional MRI can be difficult since reactive alterations to the blood-brain barrier with contrast enhancement may mimic tumour progression (i.e. pseudoprogression, PsP). The aim of this study was to assess the clinical value of O-(2-(18)F-fluoroethyl)-L-tyrosine ((18)F-FET) PET in the differentiation of PsP and early tumour progression (EP) after radiochemotherapy of glioblastoma.

METHODS

A group of 22 glioblastoma patients with new contrast-enhancing lesions or lesions showing increased enhancement (>25 %) on standard MRI within the first 12 weeks after completion of radiochemotherapy with concomitant temozolomide (median 7 weeks) were additionally examined using amino acid PET with (18)F-FET. Maximum and mean tumour-to-brain ratios (TBRmax, TBRmean) were determined. (18)F-FET uptake kinetic parameters (i.e. patterns of time-activity curves, TAC) were also evaluated. Classification as PsP or EP was based on the clinical course (no treatment change at least for 6 months), follow-up MR imaging and/or histopathological findings. Imaging results were also related to overall survival (OS).

RESULTS

PsP was confirmed in 11 of the 22 patients. In patients with PsP, (18)F-FET uptake was significantly lower than in patients with EP (TBRmax 1.9 ± 0.4 vs. 2.8 ± 0.5, TBRmean 1.8 ± 0.2 vs. 2.3 ± 0.3; both P < 0.001) and presence of MGMT promoter methylation was significantly more frequent (P = 0.05). Furthermore, a TAC type II or III was more frequently present in patients with EP (P = 0.04). Receiver operating characteristic analysis showed that the optimal (18)F-FET TBRmax cut-off value for identifying PsP was 2.3 (sensitivity 100 %, specificity 91 %, accuracy 96 %, AUC 0.94 ± 0.06; P < 0.001). Univariate survival analysis showed that a TBRmax <2.3 predicted a significantly longer OS (median OS 23 vs. 12 months; P = 0.046).

CONCLUSION

(18)F-FET PET may facilitate the diagnosis of PsP following radiochemotherapy of glioblastoma.

The conditions of primary infection define the load of latent viral genome in organs and the risk of recurrent cytomegalovirus disease

Recurrence of cytomegalovirus (CMV) from latency is a frequent cause of disease in immunocompromised patients. To date, there is no explanation for the diversity in the clinical manifestations. Primary infection can occur perinatally or later in life, and inevitably results in latent infection. Seropositivity for antibodies against CMV is indicative of latent infection, but is insufficient as a predictor for the risk of recurrence. As a model for this important medical problem, we compared the risks of murine CMV recurrence from latency established after neonatal primary infection and after infection at adult age. The risk of CMV recurrence was high only after neonatal infection. The copy number of latent viral genome in tissues was identified as the key parameter that determines the overall and organ-specific risks of recurrence. Latent CMV burden and risk of recurrence were related to the extent of virus multiplication during primary infection. The presence of latent CMV in multiple organs provides the molecular basis for stochastic events of recurrence in single organs or in any combination thereof. These findings are discussed as a concept of multifocal CMV latency and recurrence. It provides a rationale for the diversity in the clinical outcome of CMV disease.

Prognostic significance of molecular markers and extent of resection in primary glioblastoma patients

PURPOSE

Despite multimodal aggressive treatment glioblastoma patients still face a rather poor prognosis. Recent data indicate that certain molecular markers, in particular MGMT promoter hypermethylation, are associated with response to alkylating chemotherapy and longer survival. The clinical significance of other glioblastoma-associated molecular aberrations and their relationship to MGMT promoter hypermethylation is still poorly understood.

EXPERIMENTAL DESIGN

We conducted a translational study involving 67 newly diagnosed glioblastoma patients treated at our institution from 1998 to 2004. All patients were treated by open resection, followed by radiotherapy and adjuvant temozolomide chemotherapy. The tumors were investigated for MGMT promoter methylation, mRNA and protein expression, as well as presence of MGMT sequence polymorphisms. In addition, we screened for genetic aberrations of the EGFR, TP53, CDK4, MDM2, and PDGFRA genes as well as allelic losses on chromosomal arms 1p, 10q, and 19q.

RESULTS

Correlation of molecular findings with clinical data revealed significantly longer time to progression after onset of chemotherapy and longer overall survival of patients with MGMT-hypermethylated tumors. In contrast, MGMT protein expression, MGMT polymorphisms, and aberrations in any of the other genes and chromosomes were not significantly linked to patient outcome. Multivariate analysis identified MGMT promoter hypermethylation and near-complete tumor resection as the most important parameters associated with better prognosis.

CONCLUSION

Our study provides novel insights into the significance of molecular and clinical markers in predicting the prognosis of glioblastoma patients, which may improve stratification of patients into distinct prognostic subgroups.

A brief history of time (constants)

That the cerebral cortex processes information at prodigious speeds cannot be doubted. Yet the passive time constant, tau(m), of neurons, often thought of as a measure of the neuron's "response time' to synaptic input, is relatively long. In the 1950s, tau(m) was estimated to be only a few milliseconds for mammalian central neurons; with improvement in recording techniques, its estimated value grew over the years and it now stands near 20-100 msec. However, as we will argue here, the functional meaning of tau(m) is ambiguous. On the basis of a newly introduced definition of local delay, we show that the time window for synaptic integration in passive dendritic trees can be much smaller than the time constant. We argue that the voltage response to very brief synaptic inputs is essentially independent of tau(m). We discuss how tau(m) can change dynamically with the global activity of the network, as well as the difficulties of defining a time constant in structures with voltage-dependent elements. We conclude that the classically defined tau(m) only provides a very rough estimate, typically an overestimate, of the response time of neurons and that alternative measures are required to capture the dependency of the time course of the membrane potential on ligand-gated and/or voltage-dependent membrane conductances.

Self-reported quality of life of adolescents with cerebral palsy: a cross-sectional and longitudinal analysis

BACKGROUND

Children with cerebral palsy who can self-report have similar quality of life (QoL) to their able-bodied peers. Is this similarity also found in adolescence? We examined how self-reported QoL of adolescents with cerebral palsy varies with impairment and compares with the general population, and how factors in childhood predict adolescent QoL.

METHODS

We report QoL outcomes in a longitudinal follow-up and cross-sectional analysis of individuals included in the SPARCLE1 (childhood) and SPARCLE2 (adolescent) studies. In 2004 (SPARCLE1), a cohort of 818 children aged 8-12 years were randomly selected from population-based cerebral palsy registers in nine European regions. We gathered data from 500 participants about QoL with KIDSCREEN (ten domains); frequency of pain; child psychological problems (Strengths and Difficulties Questionnaire); and parenting stress (Parenting Stress Index). At follow-up in 2009 (SPARCLE2), 355 (71%) adolescents aged 13-17 years remained in the study and self-reported QoL (longitudinal sample). 76 additional adolescents self-reported QoL in 2009, providing data for 431 adolescents in the cross-sectional sample. Researchers gathered data at home visits. We compared QoL against matched controls in the general population. We used multivariable regression to relate QoL of adolescents with cerebral palsy to impairments (cross-sectional analysis) and to childhood QoL, pain, psychological problems, and parenting stress (longitudinal analysis).

FINDINGS

Severity of impairment was significantly associated (p<0·01) with reduced adolescent QoL on only three domains (Moods and emotions, Autonomy, and Social support and peers); average differences in QoL between the least and most able groups were generally less than 0·5 SD. Adolescents with cerebral palsy had significantly lower QoL than did those in the general population in only one domain (Social support and peers; mean difference -2·7 [0·25 SD], 95% CI -4·3 to -1·4). Pain in childhood or adolescence was strongly associated with low adolescent QoL on eight domains. Childhood QoL was a consistent predictor of adolescent QoL. Child psychological problems and parenting stress in childhood or their worsening between childhood and adolescence predicted only small reductions in adolescent QoL.

INTERPRETATION

Individual and societal attitudes should be affected by the similarity of the QoL of adolescents with and without cerebral palsy. Adolescents with cerebral palsy need particular help to maintain and develop peer relationships. Interventions in childhood to alleviate psychological difficulties, parenting stress, and especially pain, are justified for their intrinsic value and for their longer term effect on adolescent QoL.

FUNDING

SPARCLE1 was funded by the European Union Research Framework 5 Program (grant number QLG5-CT-2002-00636), the German Ministry of Health GRR-58640-2/14, and the German Foundation for the Disabled Child. SPARCLE2 was funded by: Wellcome Trust WT086315 A1A (UK and Ireland); Medical Faculty of the University of Lübeck E40-2009 and E26-2010 (Germany); CNSA, INSERM, MiRe-DREES, and IRESP (France); Ludvig and Sara Elsass Foundation, The Spastics Society and Vanforefonden (Denmark); Cooperativa Sociale "Gli Anni in Tasca" and Fondazione Carivit, Viterbo (Italy); Göteborg University-Riksforbundet for Rorelsehindrade Barn och Ungdomar and the Folke Bernadotte Foundation (Sweden).

Physiology, morphology and detailed passive models of guinea-pig cerebellar Purkinje cells

1. Purkinje cells (PCs) from guinea-pig cerebellar slices were physiologically characterized using intracellular techniques. Extracellular caesium ions were used to linearize the membrane properties of PCs near the resting potential. Under these conditions the average input resistance, RN, was 29 M omega, the average system time constant, tau 0, was 82 ms and the average cable length, LN, was 0.59. 2. Three PCs were fully reconstructed following physiological measurements and staining with horseradish peroxidase. Assuming that each spine has an area of 1 micron 2 and that the spine density over the spiny dendrites is ten spines per micrometre length, the total membrane area of each PC is approximately 150,000 microns 2, of which approximately 100,000 microns 2 is in the spines. 3. Detailed passive cable and compartmental models were built for each of the three reconstructed PCs. Computational methods were devised to incorporate globally the huge number of spines into these models. In all three cells the models predict that the specific membrane resistivity, Rm, of the soma is much lower than the dendritic Rm (approximately 500 and approximately 100,000 omega cm2 respectively). The specific membrane capacitance, Cm, is estimated to be 1.5-2 muF cm-2 and the specific cytoplasm resistivity, Ri, is 250 omega cm. 4. The average cable length of the dendrites according to the model is 0.13 lambda, suggesting that under caesium conditions PCs are electrically very compact. Brief somatic spikes, however, are expected to attenuate 30-fold when spreading passively into the dendritic terminals. A simulated 200 Hz train of fast, 90 mV somatic spikes produced a smooth 12 mV steady depolarization at the dendritic terminals. 5. A transient synaptic conductance increase, with a 1 nS peak at 0.5 ms and a driving force of 60 mV, is expected to produce approximately 20 mV peak depolarization at the spine head membrane. This EPSP then attenuates between 200- and 900-fold into the soma. Approximately 800 randomly distributed and synchronously activated spiny inputs are required to fire the soma. 6. The passive model of the PC predicts a poor resolution of the spatio-temporal pattern of the parallel fibre input. An equally sized, randomly distributed group of approximately 1% of the parallel fibres, activated within a time window of a few milliseconds, would result in approximately the same composite EPSP at the soma.

Structure-activity relationships in a series of substituted indolocarbazoles: topoisomerase I and protein kinase C inhibition and antitumoral and antimicrobial properties

A series of compounds structurally related to staurosporine, rebeccamycin, and corresponding aglycones was synthesized, and their activities toward protein kinase C and topoisomerases I and II were tested together with their in vitro antitumor efficiency against murine B16 melanoma and P388 leukemia cells. Their antimicrobial activities were also examined against a Gram-negative bacterium (Escherichia coli), a yeast (Candida albicans), and three Gram-positive bacteria (Bacillus cereus, Streptomyces chartreusis, and Streptomyces griseus). To avoid side effects expected with protein kinase C inhibitors, we introduced substitution on the maleimide nitrogen and/or a sugar moiety linked to one of the indole nitrogens to obtain specific inhibitors of topoisomerase I with minimal activities on protein kinase C. As expected, these structures were inefficient on topoisomerase II, and some of them exhibited a strong activity against topoisomerase I. Generally, dechlorinated compounds were found to be more active than chlorinated analogues against both purified topoisomerase I and protein kinase C. On the other hand, opposite results were obtained in the cell antiproliferative assays. These results suggest lack of cell membrane permeability in the absence of the chlorine residue or cleavage of carbon-chlorine bonds inside the cell.

Glioblastoma multiforme of the elderly: the prognostic effect of resection on survival

According to recent developments the best treatment options for glioblastoma (GBM) consist in maximum safe resection and additional adjuvant treatment with radiotherapy (RT) and alkylating chemotherapy (CHX). These options have been evaluated for populations with a median age of approximately 58 years. We therefore addressed the issue of whether elderly patients (>65 years) could also benefit from cytoreductive surgery (CS) and adjuvant treatment using alkylating chemotherapy. One-hundred and three patients suffering from newly diagnosed, primary supratentorial glioblastoma multiforme >65 years (median 70.8 years) were identified in our single-center glioma database (2002-2007) and retrospectively divided into group A (n = 31) treated with surgery alone (biopsy, BY, n = 21, CS n = 10), group B (n = 37) surgery plus radiation (BY n = 18, CS n = 19), and group C (n = 35) surgery, RT and CHX (BY n = 4, CS n = 31). Progression-free survival (PFS) and overall survival (OAS) were determined in each group and correlated to age, Karnofsky performance score (KPS), and extent of resection (biopsy (BY), partial (PR), and complete resection (CR)). Progression was defined according the Macdonald criteria. For all patients PFS and OAS were 3.2 months and 5.1 months (m) respectively. PFS and OAS for groups A/B/C were 1.8/3.2/6.4 m (P = 0.000) and 2.2/4.4/15.0 m (P = 0.000), respectively. Median age for groups A/B/C was 74.4/70.6/68.5 years and median KPS was 60/70/80. Age (<75, ≥75) was inversely correlated with OAS (5.8/2.5 m, P = 0.01). KPS (<70, ≥70) was correlated with OAS 2.4/6.5 m (P = 0.000). Extent of resection (BY, PR, or CR) correlated with PFS (2.1/3.4/6.4 m, P = 0,000) and OS (2.2/7.0/13.9 m, P = 0,000), respectively. Our study shows that elderly GBM patients can benefit from maximum treatment procedures with cytoreductive microsurgery, radiation therapy, and chemotherapy. Treatment options are obviously affected by KPS and age. The most impressive outcome predictor in this population was the extent of microsurgical resection for patients treated with adjuvant radiotherapy and chemotherapy. To conclude, elderly GBM patients should not be per se excluded from intensive treatment procedures.

The use of dynamic O-(2-18F-fluoroethyl)-l-tyrosine PET in the diagnosis of patients with progressive and recurrent glioma

BACKGROUND

We evaluated the diagnostic value of static and dynamic O-(2-[(18)F]fluoroethyl)-L-tyrosine ((18)F-FET) PET parameters in patients with progressive or recurrent glioma.

METHODS

We retrospectively analyzed 132 dynamic (18)F-FET PET and conventional MRI scans of 124 glioma patients (primary World Health Organization grade II, n = 55; grade III, n = 19; grade IV, n = 50; mean age, 52 ± 14 y). Patients had been referred for PET assessment with clinical signs and/or MRI findings suggestive of tumor progression or recurrence based on Response Assessment in Neuro-Oncology criteria. Maximum and mean tumor/brain ratios of (18)F-FET uptake were determined (20-40 min post-injection) as well as tracer uptake kinetics (ie, time to peak and patterns of the time-activity curves). Diagnoses were confirmed histologically (95%) or by clinical follow-up (5%). Diagnostic accuracies of PET and MR parameters for the detection of tumor progression or recurrence were evaluated by receiver operating characteristic analyses/chi-square test.

RESULTS

Tumor progression or recurrence could be diagnosed in 121 of 132 cases (92%). MRI and (18)F-FET PET findings were concordant in 84% and discordant in 16%. Compared with the diagnostic accuracy of conventional MRI to diagnose tumor progression or recurrence (85%), a higher accuracy (93%) was achieved by (18)F-FET PET when a mean tumor/brain ratio ≥2.0 or time to peak <45 min was present (sensitivity, 93%; specificity, 100%; accuracy, 93%; positive predictive value, 100%; P < .001).

CONCLUSION

Static and dynamic (18)F-FET PET parameters differentiate progressive or recurrent glioma from treatment-related nonneoplastic changes with higher accuracy than conventional MRI.

Focal transcriptional activity of murine cytomegalovirus during latency in the lungs

Interstitial pneumonia is a frequent and critical manifestation of human cytomegalovirus (CMV) disease in immunocompromised patients, in particular in recipients of bone marrow transplantation. Previous work in the murine CMV infection model has identified the lungs as a major organ site of CMV latency and recurrence. It was open to question whether the viral genome is transcriptionally silent or active during latency. Transcription could be latency associated and thus be part of the latency phenotype. Alternatively, transcriptional activity could reflect episodes of reactivation. We demonstrate here that transcription of the immediate-early (IE) transcription unit ie1-ie3 selectively generates ie1-specific transcripts during latency. Notably, while the latent viral DNA was found to be evenly distributed in the lungs, transcription was focal and randomly distributed. This finding indicates that IE transcription is not a feature inherent to murine CMV latency but rather reflects foci of primordial reactivation. However, this reactivation did not initiate productive infection, since ie3 gene mRNA specifying the essential transactivator IE3 of murine CMV early gene expression was not detectable. Accordingly, transcripts encoding gB were absent during latency. By contrast, during induced virus recurrence, IE-phase transcription switched from focal to generalized and ie3-specific transcripts were generated. These data imply that latency and recurrence are regulated not only at the IE promoter-enhancer and that there exists an additional checkpoint at the level of precursor RNA splicing. We propose that focal transcription reflects random episodes of nonproductive reactivation that get terminated before IE3 is expressed and ignites the productive cycle.

Coronary artery disease is associated with Alzheimer disease neuropathology in APOE4 carriers

OBJECTIVE

To examine the associations between postmortem Alzheimer disease (AD) neuropathology and autopsy-verified cardiovascular disease.

METHODS

The authors examined 99 subjects (mean age at death = 87.6; SD = 8.7) from the Mount Sinai School of Medicine Department of Psychiatry Brain Bank who were devoid of cerebrovascular disease-associated lesions or of non-AD-related neuropathology. Density of neuritic plaques (NPs) and neurofibrillary tangles (NFTs) as well as coronary artery and aortic atherosclerosis, left ventricular wall thickness, and heart weight were measured. Partial correlations were used to assess the associations of the four cardiovascular variables with NPs and NFTs in the hippocampus, entorhinal cortex, and multiple regions of the cerebral cortex after controlling for age at death, sex, dementia severity, body mass index, and ApoE genotype. These analyses were also repeated separately for ApoE4 carriers and noncarriers.

RESULTS

The extent of coronary artery disease and to a lesser extent atherosclerosis were significantly associated with the density of cardinal neuropathologic lesions of AD in this autopsy sample (significant correlations between 0.22 and 0.29). These associations were more pronounced for the ApoE4 allele carriers (n = 42; significant correlations between 0.34 and 0.47).

CONCLUSIONS

The degree of coronary artery disease is independently associated with the cardinal neuropathological lesions of Alzheimer disease. These associations are primarily attributable to individuals with the ApoE4 allele.

Modeling back propagating action potential in weakly excitable dendrites of neocortical pyramidal cells

Simultaneous recordings from the soma and apical dendrite of layer V neocortical pyramidal cells of young rats show that, for any location of current input, an evoked action potential (AP) always starts at the axon and then propagates actively, but decrementally, backward into the dendrites. This back-propagating AP is supported by a low density (-gNa = approximately 4 mS/cm2) of rapidly inactivating voltage-dependent Na+ channels in the soma and the apical dendrite. Investigation of detailed, biophysically constrained, models of reconstructed pyramidal cells shows the following. (i) The initiation of the AP first in the axon cannot be explained solely by morphological considerations; the axon must be more excitable than the soma and dendrites. (ii) The minimal Na+ channel density in the axon that fully accounts for the experimental results is about 20-times that of the soma. If -gNa in the axon hillock and initial segment is the same as in the soma [as recently suggested by Colbert and Johnston [Colbert, C. M. & Johnston, D. (1995) Soc. Neurosci. Abstr. 21, 684.2]], then -gNa in the more distal axonal regions is required to be about 40-times that of the soma. (iii) A backward propagating AP in weakly excitable dendrites can be modulated in a graded manner by background synaptic activity. The functional role of weakly excitable dendrites and a more excitable axon for forward synaptic integration and for backward, global, communication between the axon and the dendrites is discussed.

Role of O-(2-18F-fluoroethyl)-L-tyrosine PET as a diagnostic tool for detection of malignant progression in patients with low-grade glioma

In patients with low-grade glioma (LGG) of World Health Organization (WHO) grade II, early detection of progression to WHO grade III or IV is of high clinical importance because the initiation of a specific treatment depends mainly on the WHO grade. In a significant number of patients with LGG, however, information on tumor activity and malignant progression cannot be obtained on the basis of clinical or conventional MR imaging findings only. We here investigated the potential of O-(2-(18)F-fluoroethyl)-L-tyrosine ((18)F-FET) PET to noninvasively detect malignant progression in patients with LGG.

METHODS

Twenty-seven patients (mean age ± SD, 44 ± 15 y) with histologically proven LGG (WHO grade II) were investigated longitudinally twice using dynamic (18)F-FET PET and routine MR imaging. Initially, MR imaging and PET scans were performed, and diagnosis was confirmed on the basis of biopsy. Subsequently, PET scans were obtained when clinical findings or contrast-enhanced MR imaging suggested malignant progression. Maximum and mean tumor-to-brain ratios (20-40 min after injection) (TBRmax and TBRmean, respectively) of (18)F-FET uptake as well as tracer uptake kinetics (i.e., time to peak [TTP] and patterns of the time-activity curves) were determined. The diagnostic accuracy of imaging parameters for the detection of malignant progression was evaluated by receiver-operating-characteristic analyses and by Fisher exact test for 2 × 2 contingency tables.

RESULTS

In patients with histologically proven malignant progression toward WHO grade III or IV (n = 18), TBRmax and TBRmean increased significantly, compared with baseline (TBRmax, 3.8 ± 1.0 vs. 2.4 ± 1.0; TBRmean, 2.2 ± 0.3 vs. 1.6 ± 0.6; both P < 0.001), whereas TTP decreased significantly (median TTP, 35 vs. 23 min; P < 0.001). Furthermore, time-activity curve patterns changed significantly in 10 of 18 patients (P < 0.001). The combined analysis of (18)F-FET PET parameters (i.e., changes of TBRmax, TTP, or time-activity curve pattern) yielded a significantly higher diagnostic accuracy for the detection of malignant progression than changes of contrast enhancement in MR imaging (accuracy, 81% vs. 63%; P = 0.003).

CONCLUSION

Both tumor-to-brain ratio and kinetic parameters of (18)F-FET PET uptake provide valuable diagnostic information for the noninvasive detection of malignant progression of LGG. Thus, repeated (18)F-FET PET may be helpful for further treatment decisions.

European study of frequency of participation of adolescents with and without cerebral palsy

Children with cerebral palsy participate less in everyday activities than children in the general populations. During adolescence, rapid physical and psychological changes occur which may be more difficult for adolescents with impairments. Within the European SPARCLE project we measured frequency of participation of adolescents with cerebral palsy by administering the Questionnaire of Young People's Participation to 667 adolescents with cerebral palsy or their parents from nine European regions and to 4666 adolescents from the corresponding general populations. Domains and single items were analysed using respectively linear and logistic regression. Adolescents with cerebral palsy spent less time with friends and had less autonomy in their daily life than adolescents in the general populations. Adolescents with cerebral palsy participated much less in sport but played electronic games at least as often as adolescents in the general populations. Severity of motor and intellectual impairment had a significant impact on frequency of participation, the more severely impaired being more disadvantaged. Adolescents with an only slight impairment participated in some domains as often as adolescents in the general populations. Regional variation existed. For example adolescents with cerebral palsy in central Italy were most disadvantaged according to decisional autonomy, while adolescents with cerebral palsy in east Denmark and northern England played sports as often as their general populations. Participation is an important health outcome. Personal and environmental predictors of participation of adolescents with cerebral palsy need to be identified in order to design interventions directed to such predictors; and in order to inform the content of services.

Recurrence Pattern Analysis of Primary Glioblastoma

BACKGROUND

Typical recurrence of glioblastoma occurs locally, usually within 2 cm from the original lesion. With improvement of surgical techniques, more aggressive surgical strategies have become feasible, resulting in a significantly increased rate of complete resection. We investigated whether these improvements are also reflected by tumor recurrence pattern.

METHODS

Inclusion criteria were first diagnosis of glioblastoma with standard adjuvant radiochemotherapy and histologically proven tumor recurrence. Patients were divided according to recurrence pattern: local recurrence, distant recurrence, or both recurrence patterns. Data were correlated with extent of resection, molecular tumor configuration, clinical status, and survival data.

RESULTS

This single-center retrospective study included 97 patients with glioblastoma treated between 2007 and 2014. Local, distant, and combined tumor recurrence patterns were observed in 77 (79.3%), 10 (10.3%), and 10 patients (10.3%). Median progression-free survival of all patients was 8 months; median overall survival was 20 months. Median progression-free survival was 7 months for patients with local recurrence, 13 months for patients with distant recurrence, and 9 months for patients with both recurrence patterns (P = 0.646). Median overall survival in the 3 groups was 21 months, 20 months, and 14 months (P = 0.098). No correlation between methylguanine-deoxyribonucleic acid methyltransferase methylation status and recurrence pattern was observed.

CONCLUSIONS

Despite complete resection of contrast-enhancing tumor, most recurrences occurred locally. Patients with distant tumor recurrence demonstrated increased progression-free survival. Therefore, to gain local control, we may need to shift toward a more aggressive supramarginal resection, using extensive intraoperative monitoring to avoid permanent deficits.

Suprathel®—An innovative, resorbable skin substitute for the treatment of burn victims

Autologous split skin grafts are the most reliable method for closing third degree burns. Under this scheme, donor sites as well as second degree burns under conservative treatment, however, would benefit from rapid wound closure. For this treatment, biological as well as synthetic materials are available. For the improvement of these materials, primary goals are pain reduction and easy handling in the absence of biological risk. From a synthetic copolymer mainly based on DL-lactic acid a new skin substitute was developed, marketed as Suprathel. Within the scope of a bicentric study Suprathel was compared versus paraffin gauze intraindividually applied on split skin donor sites. Wound pain was measured on the Visual Pain Analog Scale over a period of 10 days as the critical criterion. Accordingly Suprathel versus Omiderm were compared on second degree burns (degree 2a, partial thickness burns). In both study parts, Suprathel significantly reduced pain. Its easy handling was superior compared to other materials. The Suprathel membrane adhered rapidly to the wound thus protecting against infections and promoting wound healing. No allergic reactions were observed. The ability of the material to resorb ensured pain-free removal after complete healing of the wound.

Dynamic O-(2-18F-fluoroethyl)-L-tyrosine positron emission tomography differentiates brain metastasis recurrence from radiation injury after radiotherapy

Background

The aim of this study was to investigate the potential of dynamic O-(2-[18F]fluoroethyl)-L-tyrosine (18F-FET) PET for differentiating local recurrent brain metastasis from radiation injury after radiotherapy since contrast-enhanced MRI often remains inconclusive.

Methods

Sixty-two patients (mean age, 55 ± 11 y) with single or multiple contrast-enhancing brain lesions (n = 76) on MRI after radiotherapy of brain metastases (predominantly stereotactic radiosurgery) were investigated with dynamic 18F-FET PET. Maximum and mean tumor-to-brain ratios (TBRmax, TBRmean) of 18F-FET uptake were determined (20-40 min postinjection) as well as tracer uptake kinetics (ie, time-to-peak and slope of time-activity curves). Diagnoses were confirmed histologically (34%; 26 lesions in 25 patients) or by clinical follow-up (66%; 50 lesions in 37 patients). Diagnostic accuracies of PET parameters for the correct identification of recurrent brain metastasis were evaluated by receiver-operating-characteristic analyses or the chi-square test.

Results

TBRs were significantly higher in recurrent metastases (n = 36) than in radiation injuries (n = 40) (TBRmax 3.3 ± 1.0 vs 2.2 ± 0.4, P < .001; TBRmean 2.2 ± 0.4 vs 1.7 ± 0.3, P < .001). The highest accuracy (88%) for diagnosing local recurrent metastasis could be obtained with TBRs in combination with the slope of time-activity curves (P < .001).

Conclusions

The results of this study confirm previous preliminary observations that the combined evaluation of the TBRs of 18F-FET uptake and the slope of time-activity curves can differentiate local brain metastasis recurrence from radiation-induced changes with high accuracy. 18F-FET PET may thus contribute significantly to the management of patients with brain metastases.