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1.
J Synchrotron Radiat ; 24(Pt 5): 963-974, 2017 Sep 01.
Article in English | MEDLINE | ID: mdl-28862618

ABSTRACT

EIGER is a single-photon-counting hybrid pixel detector developed at the Paul Scherrer Institut, Switzerland. It is designed for applications at synchrotron light sources with photon energies above 5 keV. Features of EIGER include a small pixel size (75 µm × 75 µm), a high frame rate (up to 23 kHz), a small dead-time between frames (down to 3 µs) and a dynamic range up to 32-bit. In this article, the use of EIGER as a detector for electrons in low-energy electron microscopy (LEEM) and photoemission electron microscopy (PEEM) is reported. It is demonstrated that, with only a minimal modification to the sensitive part of the detector, EIGER is able to detect electrons emitted or reflected by the sample and accelerated to 8-20 keV. The imaging capabilities are shown to be superior to the standard microchannel plate detector for these types of applications. This is due to the much higher signal-to-noise ratio, better homogeneity and improved dynamic range. In addition, the operation of the EIGER detector is not affected by radiation damage from electrons in the present energy range and guarantees more stable performance over time. To benchmark the detector capabilities, LEEM experiments are performed on selected surfaces and the magnetic and electronic properties of individual iron nanoparticles with sizes ranging from 8 to 22 nm are detected using the PEEM endstation at the Surface/Interface Microscopy (SIM) beamline of the Swiss Light Source.

2.
J Synchrotron Radiat ; 23(2): 385-94, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26917124

ABSTRACT

JUNGFRAU (adJUstiNg Gain detector FoR the Aramis User station) is a two-dimensional hybrid pixel detector for photon science applications at free-electron lasers and synchrotron light sources. The JUNGFRAU 0.4 prototype presented here is specifically geared towards low-noise performance and hence soft X-ray detection. The design, geometry and readout architecture of JUNGFRAU 0.4 correspond to those of other JUNGFRAU pixel detectors, which are charge-integrating detectors with 75 µm × 75 µm pixels. Main characteristics of JUNGFRAU 0.4 are its fixed gain and r.m.s. noise of as low as 27 e(-) electronic noise charge (<100 eV) with no active cooling. The 48 × 48 pixels JUNGFRAU 0.4 prototype can be combined with a charge-sharing suppression mask directly placed on the sensor, which keeps photons from hitting the charge-sharing regions of the pixels. The mask consists of a 150 µm tungsten sheet, in which 28 µm-diameter holes are laser-drilled. The mask is aligned with the pixels. The noise and gain characterization, and single-photon detection as low as 1.2 keV are shown. The performance of JUNGFRAU 0.4 without the mask and also in the charge-sharing suppression configuration (with the mask, with a `software mask' or a `cluster finding' algorithm) is tested, compared and evaluated, in particular with respect to the removal of the charge-sharing contribution in the spectra, the detection efficiency and the photon rate capability. Energy-dispersive and imaging experiments with fluorescence X-ray irradiation from an X-ray tube and a synchrotron light source are successfully demonstrated with an r.m.s. energy resolution of 20% (no mask) and 14% (with the mask) at 1.2 keV and of 5% at 13.3 keV. The performance evaluation of the JUNGFRAU 0.4 prototype suggests that this detection system could be the starting point for a future detector development effort for either applications in the soft X-ray energy regime or for an energy-dispersive detection system.

3.
Rev Sci Instrum ; 86(12): 123110, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26724009

ABSTRACT

JUNGFRAU (adJUstiNg Gain detector FoR the Aramis User station) is a two-dimensional hybrid pixel detector for photon science applications in free electron lasers, particularly SwissFEL, and synchrotron light sources. JUNGFRAU is an automatic gain switching, charge-integrating detector which covers a dynamic range of more than 10(4) photons of an energy of 12 keV with a good linearity, uniformity of response, and spatial resolving power. The JUNGFRAU 1.0 application-specific integrated circuit (ASIC) features a 256 × 256 pixel matrix of 75 × 75 µm(2) pixels and is bump-bonded to a 320 µm thick Si sensor. Modules of 2 × 4 chips cover an area of about 4 × 8 cm(2). Readout rates in excess of 2 kHz enable linear count rate capabilities of 20 MHz (at 12 keV) and 50 MHz (at 5 keV). The tolerance of JUNGFRAU to radiation is a key issue to guarantee several years of operation at free electron lasers and synchrotrons. The radiation hardness of JUNGFRAU 1.0 is tested with synchrotron radiation up to 10 MGy of delivered dose. The effect of radiation-induced changes on the noise, baseline, gain, and gain switching is evaluated post-irradiation for both the ASIC and the hybridized assembly. The bare JUNGFRAU 1.0 chip can withstand doses as high as 10 MGy with minor changes to its noise and a reduction in the preamplifier gain. The hybridized assembly, in particular the sensor, is affected by the photon irradiation which mainly shows as an increase in the leakage current. Self-healing of the system is investigated during a period of 11 weeks after the delivery of the radiation dose. Annealing radiation-induced changes by bake-out at 100 °C is investigated. It is concluded that the JUNGFRAU 1.0 pixel is sufficiently radiation-hard for its envisioned applications at SwissFEL and synchrotron beam lines.


Subject(s)
Artifacts , Electronics/instrumentation , Photometry/instrumentation , Photons , Radiometry/instrumentation , Semiconductors , Equipment Design , Equipment Failure , Equipment Failure Analysis , Reproducibility of Results , Sensitivity and Specificity , Signal-To-Noise Ratio , Static Electricity
4.
J Synchrotron Radiat ; 19(Pt 6): 1001-5, 2012 Nov.
Article in English | MEDLINE | ID: mdl-23093761

ABSTRACT

Eiger is the next-generation single-photon-counting pixel detector following the widely used Pilatus detector. Its smaller pixel size of 75 µm × 75 µm, higher frame rate of up to 22 kHz, and practically zero dead-time (~4 µs) between exposures will further various measurement methods at synchrotron sources. In this article Eiger's suitability for X-ray photon correlation spectroscopy (XPCS) is demonstrated. By exploiting its high frame rate, complementary small-angle X-ray scattering (SAXS) and XPCS data are collected in parallel to determine both the structure factor and collective diffusion coefficient of a nano-colloid suspension. For the first time, correlation times on the submillisecond time scale are accessible with a large-area pixel detector.

5.
J Synchrotron Radiat ; 19(Pt 3): 359-65, 2012 May.
Article in English | MEDLINE | ID: mdl-22514170

ABSTRACT

A synchrotron beam has been used to test the spatial resolution of a single-photon-resolving integrating readout-chip coupled to a 320 µm-thick silicon strip sensor with a dedicated readout system. Charge interpolation methods have yielded a spatial resolution of σ(x) ≃ 1.8 µm for a 20 µm-pitch strip.

6.
J Synchrotron Radiat ; 16(Pt 4): 489-93, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19535862

ABSTRACT

A synchrotron beam has been used to investigate the radiation tolerance of a PILATUS II module. It has been demonstrated that radiation-induced threshold shifts become significant above 30 Mrad. Individual adjustment of pixel thresholds after irradiation enabled retention of standard behaviour in excess of 40 Mrad. This implies that a module can be continuously irradiated for in excess of 40 days at an individual pixel count rate of 10(6) counts s(-1).

7.
J Synchrotron Radiat ; 16(Pt 3): 368-75, 2009 May.
Article in English | MEDLINE | ID: mdl-19395800

ABSTRACT

PILATUS is a silicon hybrid pixel detector system, operating in single-photon-counting mode, that has been developed at the Paul Scherrer Institut for the needs of macromolecular crystallography at the Swiss Light Source (SLS). A calibrated PILATUS module has been characterized with monochromatic synchrotron radiation. The influence of charge sharing on the count rate and the overall energy resolution of the detector were investigated. The dead-time of the system was determined using the attenuated direct synchrotron beam. A single module detector was also tested in surface diffraction experiments at the SLS, whereby its performance regarding fluorescence suppression and saturation tolerance were evaluated, and have shown to greatly improve the sensitivity, reliability and speed of surface diffraction data acquisition.


Subject(s)
Photometry/instrumentation , Radiometry/instrumentation , Transducers , X-Ray Diffraction/instrumentation , Computer-Aided Design , Equipment Design , Equipment Failure Analysis , Photometry/methods , Photons , Radiation Dosage , Reproducibility of Results , Sensitivity and Specificity
8.
J Clin Oncol ; 20(9): 2267-76, 2002 May 01.
Article in English | MEDLINE | ID: mdl-11980997

ABSTRACT

PURPOSE: To compare survival and toxicity in adult patients treated with low-dose (50.4 Gy/28 fractions) versus high-dose (64.8 Gy/36 fractions) localized radiation therapy (RT) for supratentorial low-grade astrocytoma, oligodendroglioma, and mixed oligoastrocytoma. PATIENTS AND METHODS: From 1986 to 1994, 203 eligible/analyzable patients were randomized: 101 to low-dose RT, 102 to high-dose RT. Almost half were younger than 40 years, and 95% had grade 2 tumors. Histologic subtype was astrocytoma (or mixed oligo-astrocytoma with astrocytoma dominant) in 32% of patients and oligodendroglioma (or oligoastrocytoma with oligodendroglioma dominant) in 68%. Tumor diameter was less than 5 cm in 35% of patients, and 41% of tumors showed some degree of contrast enhancement. Extent of resection was gross total in 14% of patients, subtotal in 35%, and biopsy only in 51%. RESULTS: At the time of the present analysis, 83 patients (41%) are dead, and median follow-up is 6.43 years in the 120 who are still alive. Survival at 2 and 5 years is nonsignificantly better with low-dose RT; survival at 2 and 5 years was 94% and 72%, respectively, with low-dose RT and 85% and 64%, respectively, with high-dose RT (log rank P =.48). Multivariate analysis identified histologic subtype, tumor size, and age as the most significant prognostic factors. Survival is significantly better in patients who are younger than 40 years and in patients who have oligodendroglioma or oligo-dominant histology. Grade 3 to 5 radiation neurotoxicity (necrosis) was observed in seven patients, with one fatality in each treatment arm. The 2-year actuarial incidence of grade 3 to 5 radiation necrosis was 2.5% with low-dose RT and 5% with high-dose RT. CONCLUSION: This phase III prospective randomized trial of low- versus high-dose radiation therapy for adults with supratentorial low-grade astrocytoma, oligodendroglioma, and oligoastrocytoma found somewhat lower survival and slightly higher incidence of radiation necrosis in the high-dose RT arm. The most important prognostic factors for survival are histologic subtype, tumor size, and age. The study design of the ongoing intergroup trial in this population will be discussed.


Subject(s)
Glioma/radiotherapy , Supratentorial Neoplasms/radiotherapy , Adult , Aged , Chi-Square Distribution , Dose Fractionation, Radiation , Dose-Response Relationship, Radiation , Female , Glioma/pathology , Humans , Male , Middle Aged , Prognosis , Proportional Hazards Models , Prospective Studies , Radiotherapy/adverse effects , Radiotherapy Dosage , Statistics, Nonparametric , Supratentorial Neoplasms/pathology , Survival Analysis , Treatment Outcome
9.
Mayo Clin Proc ; 76(3): 327-30, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11243282

ABSTRACT

Merkel cell carcinoma is a rare primary cutaneous neuroendocrine tumor that is locally aggressive and frequently accompanied by distant metastases. Neurologic complications of Merkel cell carcinoma are rare. We describe a 69-year-old man who presented with Lambert-Eaton myasthenic syndrome and was found to have Merkel cell carcinoma. The paraneoplastic syndrome improved with initial treatment of the malignancy. He subsequently developed a solitary brain metastasis and died of leptomeningeal carcinomatosis.


Subject(s)
Carcinoma, Merkel Cell/complications , Lambert-Eaton Myasthenic Syndrome/etiology , Paraneoplastic Syndromes/etiology , Skin Neoplasms/complications , Aged , Brain Neoplasms/secondary , Carcinoma, Merkel Cell/diagnosis , Fatal Outcome , Humans , Male , Meningeal Neoplasms/secondary , Skin Neoplasms/diagnosis
10.
Anesth Analg ; 91(3): 688-90, 2000 Sep.
Article in English | MEDLINE | ID: mdl-10960400

ABSTRACT

IMPLICATIONS: The performance of regional blockade on a patient with a preexisting neurologic condition or a history of neurologic complications after regional anesthesia is controversial. We present a case of recurring brachial plexus neuropathy in a diabetic patient after two shoulder procedures performed 4 mo apart. In both cases, the patient underwent intensive physical therapy with continuous postoperative interscalene analgesia.


Subject(s)
Brachial Plexus Neuropathies/etiology , Diabetes Mellitus, Type 1/complications , Nerve Block/adverse effects , Postoperative Complications/physiopathology , Shoulder/surgery , Adult , Electromyography , Female , Humans , Recurrence
11.
J Neurosurg ; 93(2): 201-7, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10930004

ABSTRACT

OBJECT: It is standard practice for the oncological follow-up of patients with brain tumors (especially in the setting of clinical trials) to include neurological examination and neuroradiological studies such as computerized tomography (CT) or magnetic resonance (MR) imaging in addition to evaluation of the patients' symptomatology and performance score. The validity of this practice and its impact on the welfare of patients with high-grade gliomas has not been adequately assessed. The purpose of this study is to provide such an assessment. METHODS: The authors studied 231 similarly treated patients who were participating in three prospective North Central Cancer Treatment Group or Mayo Clinic trials who developed progressive disease during follow up. According to the protocol, the symptom status, performance score, results of neurological examination, and CT or MR status were recorded prospectively in each patient at each evaluation (every 6-8 weeks). At progression, 177 (77%) of 231 patients experienced worsening of their baseline symptoms or they developed new ones. In the remaining 54 asymptomatic patients (23%), neuroradiological imaging revealed the progression. Asymptomatic progression was more likely to be detected on MR imaging compared with CT studies (p < 0.01). In no asymptomatic patient was progression detected on neurological examination alone. The median survival time after tumor recurrence was 13.3 weeks in symptomatic patients compared with 41.7 weeks in the asymptomatic group (p < 0.0001). Asymptomatic patients were more aggressively treated, with surgery (p < 0.0001) and second-line chemotherapy (p < 0.0002). Multivariate analysis of survival time following first progression by using both classification and regression trees and Cox models showed that treatment at recurrence was the most important prognostic variable. CONCLUSIONS: Symptoms are the most frequent indicators of progression in patients with high-grade gliomas (77%). All asymptomatic progressions were detected on neuroradiological studies; MR imaging was more likely than CT scanning to reveal asymptomatic recurrences. Survival after disease progression was significantly longer in asymptomatic patients and could be related both to treatment following progression and to other favorable prognostic factors such as performance score.


Subject(s)
Brain Neoplasms/diagnosis , Glioma/diagnosis , Severity of Illness Index , Brain Neoplasms/classification , Brain Neoplasms/pathology , Disease Progression , Female , Glioma/classification , Glioma/pathology , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Neoplasm Recurrence, Local/diagnosis , Neoplasm Staging/methods , Neurologic Examination , Predictive Value of Tests , Survival Analysis , Tomography, X-Ray Computed
12.
Int J Radiat Oncol Biol Phys ; 47(2): 291-8, 2000 May 01.
Article in English | MEDLINE | ID: mdl-10802351

ABSTRACT

PURPOSE: To determine the maximum tolerated dose of single fraction radiosurgery in patients with recurrent previously irradiated primary brain tumors and brain metastases. METHODS AND MATERIALS: Adults with cerebral or cerebellar solitary non-brainstem tumors

Subject(s)
Brain Neoplasms/surgery , Neoplasm Recurrence, Local/surgery , Radiosurgery/methods , Adult , Analysis of Variance , Brain Diseases/etiology , Brain Neoplasms/mortality , Brain Neoplasms/secondary , Disease Progression , Humans , Neoplasm Recurrence, Local/mortality , Odds Ratio , Radiation Injuries/etiology , Radiosurgery/instrumentation , Radiotherapy Dosage , Steroids/therapeutic use , Survival Rate
13.
Mayo Clin Proc ; 74(8): 803-7, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10473358

ABSTRACT

Neurologic involvement occurs in 10% to 20% of patients with disseminated histoplasmosis. We describe a 20-year-old woman who had headache and diplopia but no evidence of systemic infection. Magnetic resonance imaging showed an enhancing mass in the thalamomesencephalic and third ventricular region. After subtotal resection of what was presumed to be a glioma, the patient had symptoms and signs of meningitis. Subsequent pathological review demonstrated noncaseating granulomas, and serologic tests and cultures confirmed the diagnosis of histoplasmosis. Initiation of antifungal therapy and removal of an infected shunt system resulted in clinical improvement. Clinicians should maintain a high index of suspicion in patients who are from any area endemic for histoplasmosis.


Subject(s)
Brain Diseases/diagnosis , Brain Diseases/microbiology , Histoplasmosis/diagnosis , Histoplasmosis/drug therapy , Adult , Antifungal Agents/therapeutic use , Brain Diseases/drug therapy , Brain Neoplasms/diagnosis , Diagnosis, Differential , Female , Humans , Magnetic Resonance Imaging
14.
Medicina (B Aires) ; 59(2): 129-32, 1999.
Article in Spanish | MEDLINE | ID: mdl-10413888

ABSTRACT

Blood transfusion is the second most common transmission route of Chagas' disease in endemic areas. Discrepancies between the available diagnostic kits are common, which indicates that a single test is not satisfactory. The aim of this work was to study the seroprevalence of anti-Trypanosoma cruzi markers, to compare sensitivity and specificity of the two screening assays currently in use and to confirm the results with a third test. A total of 20,860 volunteer blood donors were studied. Donations were screened with indirect hemagglutination assay (IHA) and enzyme immunoassay (EIA). Repeatedly reactive samples were assayed with an EIA carried out on strips, to which a mixture of T. cruzi antigens was applied as an horizontal line (DB). Sera that reacted in at least two tests were considered positive. A total of 576 samples were reactive for one or both screening tests (2.76%) and 391 of them (1.87%) were confirmed positive. EIA proved to be more sensitive, with no false negative results (100% sensibility), whereas 98 samples (0.47%) were IHA false negative (74.93% sensibility). Specificity for EIA was 99.3% and for IHA 99.8%. In our case, almost 0.9% of donated blood is discarded because of false reactive anti-T. cruzi results; two thirds correspond to false positive EIA and one third to false positive IHA. It is important to note that in our population we have not registered false negative results for EIA but there were false negative IHA. This fact implies that although the first method is less specific, it is much more sensitive. It is important to confirm the screening results in order to avoid unnecessary donor counselling and permit future donations. The DB test employed in our study results a useful alternative for this purpose.


Subject(s)
Antibodies, Protozoan/blood , Blood Donors , Trypanosoma cruzi/immunology , Animals , Argentina , False Negative Reactions , Hemagglutination Tests , Humans , Immunoenzyme Techniques , Sensitivity and Specificity , Seroepidemiologic Studies
15.
Am J Clin Oncol ; 22(2): 168-71, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10199452

ABSTRACT

There is no standard treatment for patients with recurrent gliomas, and their prognosis remains poor. 2-Chlorodeoxyadenosine is a purine analogue that has significant activity in many low-grade lymphoproliferative disorders. The authors conducted a phase II study to determine the efficacy of 2-chlorodeoxyadenosine in patients with recurrent gliomas. Patients with a histologically confirmed primary brain tumor with evidence of progression after radiation therapy were eligible. Protocol treatment consisted of 2-chlorodeoxyadenosine 7.0 mg/m2 intravenously on days 1 through 5 every 28 days. For those with a history of prior nitrosourea therapy, the dose of 2-chlorodeoxyadenosine was reduced to 5.6 mg/m2 on days 1 through 5. Treatment was continued until progression or a maximum of 12 cycles. Fifteen patients with recurrent astrocytomas or oligoastrocytomas of all grades were entered in the study. Treatment was well tolerated. Major toxicities were myelosuppression and neurotoxicity. No responses were seen. The authors conclude that although 2-chlorodeoxyadenosine is well tolerated, no demonstrable activity in patients with recurrent gliomas was established.


Subject(s)
Antineoplastic Agents/therapeutic use , Brain Neoplasms/drug therapy , Cladribine/therapeutic use , Glioma/drug therapy , Neoplasm Recurrence, Local/drug therapy , Adult , Female , Humans , Male , Middle Aged , Survival Analysis
16.
Medicina [B Aires] ; 59(2): 129-32, 1999.
Article in Spanish | BINACIS | ID: bin-40017

ABSTRACT

Blood transfusion is the second most common transmission route of Chagas disease in endemic areas. Discrepancies between the available diagnostic kits are common, which indicates that a single test is not satisfactory. The aim of this work was to study the seroprevalence of anti-Trypanosoma cruzi markers, to compare sensitivity and specificity of the two screening assays currently in use and to confirm the results with a third test. A total of 20,860 volunteer blood donors were studied. Donations were screened with indirect hemagglutination assay (IHA) and enzyme immunoassay (EIA). Repeatedly reactive samples were assayed with an EIA carried out on strips, to which a mixture of T. cruzi antigens was applied as an horizontal line (DB). Sera that reacted in at least two tests were considered positive. A total of 576 samples were reactive for one or both screening tests (2.76


) and 391 of them (1.87


) were confirmed positive. EIA proved to be more sensitive, with no false negative results (100


sensibility), whereas 98 samples (0.47


) were IHA false negative (74.93


sensibility). Specificity for EIA was 99.3


and for IHA 99.8


. In our case, almost 0.9


of donated blood is discarded because of false reactive anti-T. cruzi results; two thirds correspond to false positive EIA and one third to false positive IHA. It is important to note that in our population we have not registered false negative results for EIA but there were false negative IHA. This fact implies that although the first method is less specific, it is much more sensitive. It is important to confirm the screening results in order to avoid unnecessary donor counselling and permit future donations. The DB test employed in our study results a useful alternative for this purpose.

17.
J Clin Oncol ; 16(9): 2953-8, 1998 Sep.
Article in English | MEDLINE | ID: mdl-9738563

ABSTRACT

PURPOSE: Previous investigators have reported responses in 52% of patients treated with mechlorethamine (nitrogen mustard), vincristine, and procarbazine (MOP) for recurrent glioma. To confirm these promising results, we conducted a phase II prospective study. PATIENTS AND METHODS: Sixty-three patients with histologic confirmation of recurrent glioma were treated with the MOP regimen. Patients with or without prior chemotherapy received nitrogen mustard 3 mg/m2 or 6 mg/m2, respectively, intravenously on days 1 and 8 plus vincristine 2 mg/m2 intravenously on days 1 and 8, and procarbazine 100 mg/m2 orally on days 1 to 14. Cycles were repeated every 28 days. RESULTS: Of 61 patients assessable for response, eight responded (13%), with one complete response (CR). Responses were as follows: low-grade gliomas, 19%; anaplastic astrocytomas, 11%; anaplastic oligodendrogliomas or oligoastrocytomas, 25%; and glioblastomas, 4.3%. The most common toxicity was myelosuppression with leukocyte nadirs less than 1,000/microL in 23% and platelet nadirs less than 25,000/microL in 13% of patients. Two patients died of infection in the setting of neutropenia. Nonhematologic toxicity included neurosensory changes in 21% of patients (severe in 3%) and severe dermatologic reactions in 8%. In multivariate analysis, Eastern Cooperative Oncology group (ECOG) performance status (PS) was the best predictor for response to chemotherapy (P=.01) and time to progression (P=.008), while PS and grade were the most important predictors of survival (P=.002 and .05, respectively). CONCLUSION: This study did not confirm the high response rate previously reported in recurrent gliomas. Patients with recurrent anaplastic oligodendrogliomas or oligoastrocytomas and recurrent low-grade gliomas had the highest response rates (25% and 19%, respectively). In multivariate analysis, ECOG PS was the best predictor of response, while PS and tumor grade were the most important predictors of survival.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Brain Neoplasms/drug therapy , Glioma/drug therapy , Neoplasm Recurrence, Local/drug therapy , Adult , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Astrocytoma/drug therapy , Female , Humans , Male , Mechlorethamine/administration & dosage , Mechlorethamine/adverse effects , Middle Aged , Oligodendroglioma/drug therapy , Procarbazine/administration & dosage , Procarbazine/adverse effects , Prospective Studies , Survival Analysis , Vincristine/administration & dosage , Vincristine/adverse effects
18.
J Neurosurg ; 89(3): 425-30, 1998 Sep.
Article in English | MEDLINE | ID: mdl-9724117

ABSTRACT

OBJECT: Gliosarcoma, a rare malignancy of the central nervous system, consists of gliomatous and sarcomatous elements. There are conflicting reports regarding its aggressiveness and cell line of origin compared with those of glioblastoma multiforme (GBM). The goal of this study was to compare clinicopathological features such as disease-free survival time and actual survival time in patients with gliosarcoma with a matched group of patients with GBM as well as with the entire group of patients with GBM. METHODS: The authors report on 18 cases of gliosarcoma derived from a series of 748 Grade 4 astrocytoma cases that were part of four consecutive randomized Phase III trials conducted between 1979 and 1996. In this series the gliosarcoma group represented only 2.4% of all GBMs and included 11 men and seven women with a median age of 61.5 years (range 31-81 years). The median tumor size was 5 cm (range 2-8 cm). The locations, all supratentorial, included temporal in 44%, parietal in 28%, frontal in 17%, and occipital in 11%. The 18 patients with gliosarcomas, all Grade 4 (World Health Organization classification), were compared with the entire group of 730 patients with GBM and a control group of 18 patients with GBM matched for known prognostic factors including patient age, randomization date, performance status, extent of resection, and protocol number. Patients in all treatment groups received radiation and nitrosourea-based chemotherapy. The median time to progression and the median survival times for the patients with gliosarcoma were 28.0 and 35.1 weeks as compared with 24.7 and 41.6 weeks for the entire group of patients with GBM (log rank test, p = 0.94 and 0.27, respectively) and 16.7 and 34.4 weeks in the control group (p = 0.20 and 0.84, respectively). In previous molecular cytogenetic analyses of gliosarcoma these authors have shown similar genetic changes in the gliomatous and sarcomatous components. CONCLUSIONS: The data obtained in this study support the conclusion that gliosarcoma shares significant clinical and genetic similarities with GBM and that the same principles should be applied for patient enrollment in research protocols and treatment for these two kinds of tumor.


Subject(s)
Brain Neoplasms/surgery , Glioblastoma/surgery , Gliosarcoma/surgery , Adult , Age Factors , Aged , Aged, 80 and over , Antineoplastic Agents/therapeutic use , Brain Neoplasms/pathology , Case-Control Studies , Cell Lineage , Chemotherapy, Adjuvant , Disease Progression , Disease-Free Survival , Female , Frontal Lobe/pathology , Frontal Lobe/surgery , Glioblastoma/pathology , Gliosarcoma/pathology , Humans , Male , Middle Aged , Nitrosourea Compounds/therapeutic use , Occipital Lobe/pathology , Occipital Lobe/surgery , Parietal Lobe/pathology , Parietal Lobe/surgery , Prognosis , Radiotherapy, Adjuvant , Supratentorial Neoplasms/pathology , Supratentorial Neoplasms/surgery , Survival Rate , Temporal Lobe/pathology , Temporal Lobe/surgery , Treatment Outcome
19.
J Clin Oncol ; 16(6): 2195-201, 1998 Jun.
Article in English | MEDLINE | ID: mdl-9626221

ABSTRACT

PURPOSE: The effect of radiotherapy on the long-term cognitive performance of patients treated for intracranial neoplasm is a major concern to clinicians and patients, particularly as long-term survival or cure is possible for a small minority of patients. To assess the effects of cranial radiotherapy and chemotherapy on the cognitive performance of high-grade glioma patients, we analyzed cognitive performance data collected in a series of prospective clinical trials. METHODS: We studied 701 high-grade brain tumor patients entered onto two consecutive North Central Cancer Treatment Group (NCCTG) randomized treatment trials designed to compare radiotherapy and carmustine (BCNU) versus radiotherapy and 1-(2-chloroethyl)-3(2,6 dioxo-l-piperidyl)-1-nitrosource a (PCNU) (first trial) and radiotherapy and BCNU and interferon alfa (IFN) versus radiotherapy and BCNU (second trial). Folstein Mini-Mental Status Exam (MMSE) score and Eastern Cooperative Oncology Group (ECOG) performance score (PS) recorded at baseline and 6, 12, 18, and 24 months were analyzed to assess cognitive and physical function over time. Patients who did not demonstrate tumor progression within 60 days of the assessment time were considered nonprogressors at that evaluation. A loss of greater than 3 points on the MMSE was considered significant deterioration. RESULTS: The number of patients who experienced a greater than 3-point decrease in MMSE from baseline was 13 of 119 nonprogressors (10.9%; 95% confidence interval [CI], 6.3% to 18.9%) at 6 months, three of 54 nonprogressors (5.5%; 95% CI, 0.5% to 12.8%) at 12 months, three of 30 nonprogressors (10%; 95% CI, 2.1% to 26.5%) at 18 months, and four of 22 nonprogressors (18.2%; 95% CI, 5.2% to 40.3%) at 24 months. The CIs at all times overlapped, which indicates no statistically significant increase in the percentage of patients who experienced a significant decrease in their MMSE score. Patients who demonstrated a significant decrease in their MMSE score were significantly older than those who did not (P = .0017) at 6 months and remained so throughout follow-up; moreover, they had a significantly shorter time to progression and death. ECOG PS was strongly negatively correlated with MMSE score throughout the study, and MMSE score at all time intervals was correlated with baseline PS. CONCLUSION: In this population of glioma patients who received radiotherapy, there is no clear trend to cognitive worsening. Factors such as older age, poorer PS, and subclinical tumor progression may be more significant factors in those patients who did demonstrate a significant cognitive decline.


Subject(s)
Brain Neoplasms/therapy , Cognition/drug effects , Cognition/radiation effects , Glioma/therapy , Adolescent , Adult , Aged , Aged, 80 and over , Antineoplastic Agents, Alkylating/administration & dosage , Brain Neoplasms/mortality , Carmustine/administration & dosage , Cranial Irradiation/adverse effects , Disease Progression , Female , Glioma/mortality , Humans , Intelligence Tests , Interferon-alpha/administration & dosage , Male , Middle Aged , Nitrosourea Compounds/administration & dosage , Prospective Studies , Survival Rate
20.
Int J Radiat Oncol Biol Phys ; 40(2): 297-302, 1998 Jan 15.
Article in English | MEDLINE | ID: mdl-9457812

ABSTRACT

PURPOSE: A Phase I study to determine the safety, toxicity, and maximum tolerated dose (MTD) of carmustine (BCNU) and interferon alpha-2a (IFN-a) when combined with radiation as initial therapy in high-grade glioma. METHODS AND MATERIALS: Patients with newly diagnosed Grade 3 or 4 astrocytoma, oligoastrocytoma, or gliosarcoma were enrolled after surgery. All received radiation therapy to the brain (64.8 Gy/36 fractions), combined with a single dose of BCNU (200 mg/m2) at the start of radiation. Chemotherapy after completing radiation consisted of BCNU 150 mg/m2 once every 7 weeks, and IFN-a 12 x 10(6) units/m2 subcutaneously Days 1-3 each week of a 7-week cycle. Subsequent dose modification was based on constitutional symptoms for IFN-a and on myelosuppression for BCNU. RESULTS: Fifteen patients were entered on the study. Four were excluded because they did not receive IFN-a (3 refused treatment and 1 patient left the study due to multiple medical problems). Eleven were evaluable for toxicity and efficacy. Nonhematological toxicity, mainly lethargy and flu-like symptoms, were dose-limiting for IFN-a. After the first 6 patients were treated per the initial protocol, the frequency of IFN-a administration was decreased to Days 1-3 on weeks 1, 3, and 5 of the 7-week cycle for 5 additional patients. Lethargy, fever, chills, myalgias, alopecia, and anorexia occurred in all patients. Other toxicities included nausea and vomiting (91%), central-nervous-system depression or mood changes (64%), headaches (55%), and elevation of liver enzymes (36%). Grade 3-4 leukopenia occurred in 4 (45%) of 11 patients, and Grade 3-4 thrombocytopenia in 3 (27%) of 11 patients. Due to myelosuppressive effects, BCNU dose was not escalated. Median survival of the cohort was 44 months. Objective responses occurred in 5 (56%) of 9 patients and median duration of response was 33 months. The MTD of this combination after radiation therapy is IFN-a 12 x 10(6) units/m2 Days 1-3, on Weeks 1, 3, and 5 of a 7-week cycle and BCNU 150 mg/m2 Day 1, every 7 weeks. CONCLUSIONS: Treatment with radiation, IFN-a, and BCNU is feasible and effective in patients with high-grade gliomas, although constitutional symptoms from IFN-a are substantial.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Brain Neoplasms/drug therapy , Brain Neoplasms/radiotherapy , Glioma/drug therapy , Glioma/radiotherapy , Adult , Aged , Brain Neoplasms/pathology , Carmustine/administration & dosage , Carmustine/adverse effects , Combined Modality Therapy , Female , Glioma/pathology , Humans , Interferon alpha-2 , Interferon-alpha/administration & dosage , Interferon-alpha/adverse effects , Male , Middle Aged , Radiotherapy/adverse effects , Recombinant Proteins , Survival Analysis
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