Search

Purpose: We evaluated clinical outcomes in the subset of patients who underwent radiotherapy (RT) due to progressive pilocytic astrocytoma within the Multicenter Treatment Study for Children and Adolescents with a Low Grade Glioma HIT-LGG 1996.Patients and Methods: Eligibility criteria were fulfilled by 117 patients. Most tumors (65 %) were located in the supratentorial midline, followed by the posterior fossa (26.5 %) and the cerebral hemispheres (8.5 %). Median age at the start of RT was 9.2 years (range 0.7-17.4 years). In 75 cases, external fractionated radiotherapy (EFRT) was administered either as first-line nonsurgical treatment (n = 58) or after progression following primary chemotherapy (n = 17). The median normalized total dose was 54 Gy. Stereotactic brachytherapy (SBT) was used in 42 selected cases.Results: During a median follow-up period of 8.4 years, 4 patients (3.4 %) died and 33 (27.4 %) experienced disease progression. The 10-year overall (OS) and progression-free survival (PFS) rates were 97 and 70 %, respectively. No impact of the RT technique applied (EFRT versus SBT) on progression was observed. The 5-year PFS was 76 ± 5 % after EFRT and 65 ± 8 % after SBT. Disease progression after EFRT was not influenced by gender, neurofibromatosis type 1 (NF1) status, tumor location (hemispheres versus supratentorial midline versus posterior fossa), age or prior chemotherapy. Normalized total EFRT doses of more than 50.4 Gy did not improve PFS rates.Conclusion: EFRT plays an integral role in the treatment of pediatric pilocytic astrocytoma and is characterized by excellent tumor control. A reduction of the normalized total dose from 54 to 50.4 Gy appears to be feasible without jeopardizing tumor control. SBT is an effective treatment alternative. [ABSTRACT FROM AUTHOR]

The aim of this study was to analyse the impact of FDG-PET staging on treatment results of neo-adjuvant radiochemotherapy in patients with advanced non-small cell lung cancer (NSCLC). We compared prospectively the outcome of two patient groups with stage III NSCLC undergoing the same neo-adjuvant radio-chemotherapy (NARCT). In one group, FDG-PET was part of the pretherapeutic staging, whereas in the other group, no PET scans were performed. One hundred and eighty-eight patients with advanced stage III NSCLC were selected for a phase II trial of NARCT. The first 115 patients underwent conventional workup (CWU) and FDG-PET before inclusion (group I); the remaining 73 patients underwent CWU only (group II). All patients were followed up according to a standardised protocol for at least 11 months (up to 64 months). Overall survival and disease-free survival were used as parameters of therapeutic success and analysed statistically. After staging, 157/188 patients were included in the clinical trial. Thirty-one were excluded owing to the results of FDG-PET, in most cases because of the detection of previously unknown distant metastases. Overall survival and metastasis-free survival were significantly longer in patients of group I stratified by FDG-PET than in group II ( p=0.006 and 0.02 respectively). Another significant factor for survival was complete tumour resection ( p=0.02). Gender, histological tumour type, tumour grade and UICC stage had no significant influence. Pretherapeutic staging by FDG-PET significantly influences the results of NARCT and subsequent surgery by identifying patients not eligible for curative treatment. [ABSTRACT FROM AUTHOR]

Purpose: Recent studies have demonstrated the relevance of 18F-FDG uptake as an independent prognostic factor for recurrence of operable non-small cell lung cancer (NSCLC). This corresponds with the experimental finding that FDG uptake correlates with the proliferative activity of tumour cells (Higashi et al., J Nucl Med 2000;41:85-92). On the basis of these observations, we studied the influence of FDG uptake on prognosis and occurrence of distant metastases in patients with advanced NSCLC. Methods: One hundred and fifty-nine patients with NSCLC of UICC stage IIIA or IIIB were included in the study. In all patients, neoadjuvant treatment was planned to achieve operability. FDG PET was performed as an additional staging procedure prior to the initiation of therapy. Clinical outcome data in terms of overall survival, disease-free survival and incidence of distant metastases could be obtained for 137 patients and were correlated with the average standardised uptake value of the tumour (SUVavg). Furthermore, other factors influencing SUVavg and patient outcome (histological tumour type, grading, UICC stage, tumour size) were analysed. Results: SUVavg was significantly influenced by tumour histology, UICC stage and tumour size. No significant difference could be shown for grading. In 38 out of the 159 patients (24%), FDG PET revealed previously unsuspected distant metastases. The incidence of distant metastases significantly correlated with SUVavg. Overall survival tended to decrease with increasing SUVavg; however, significance was only reached when a cut-off of 12.0 was applied (p=0.05). Conclusion: FDG uptake is an independent prognostic factor in patients with UICC stage III NSCLC, although less distinctively so than has been reported for stage I/II tumours. [ABSTRACT FROM AUTHOR]

Background Treatment of low grade glioma of the visual pathway in children poses a challenge to the neuro-ophthalmologist and radio-oncologist owing to their low incidence and the lack of consensus about 'optimal' treatments. Objectives: To define the role of radiotherapy in present and future treatment approaches. Methods: Reports in the literature spanning 6o years of radiation therapy, including orthovoltage, megavoltage, and recent modern high-precision treatment techniques, were reviewed with respect to the impact on visual function, survival, treatment techniques, and consequences of treatment. Based on these experiences, future swategies in the management of childhood low grade g ioma are discussed. Results: Although the efficacy of radiation therapy, has been well known for more than 60 years. there are still many open questions. Location and extent of disease often precludes aggressive surgery and a conservanve approach is used today with the aim of preserving visual function, Evaluation of published reports is difficult because of short follow-up periods and the failure to present findings and results in a comparable way. Even with the shortcomings of the reports available in the literature primarily concerning indications, dose-response effects, timing, and use of 'optimal' treatment fields, fractionated radiation therapy plays an important role m the management of low grade gliomas. Improved or stable visual function is obtained in approximately 9o% of the cases. With doses of 45-54Gy with standard fractionation and limited treatment fields high local tumor control in up to 8o% and more can be achieved. Past series comprising children younger than 5 years of age, however, have reported high rares of severe late effects when using large treatment fields and inadequat fractionation schemes. There is consent today to employ radiotherapy in progressive disease only and that newer technologies, such as [SUB3]D treatmemt planning (conformal radiotherapy),... [ABSTRACT FROM AUTHOR]

Abstract Background Hypoxia compromises local control in patients with head-and-neck cancer (HNC). In order to determine the value of [18F]-fluoromisonidazole (Fmiso) with regard to tumor hypoxia, a patient study with dynamic Fmiso PET was performed. For a better understanding of tracer uptake and distribution, a kinetic model was developed to analyze dynamic Fmiso PET data. Methods For 15 HNC patients, dynamic Fmiso PET examinations were performed prior to radiotherapy (RT) treatment. The data was analyzed using a two compartment model, which allows the determination of characteristic hypoxia and perfusion values. For different parameters, such as patient age, tumor size and standardized uptake value, the correlation to treatment outcome was tested using the Wilcoxon-Mann-Whitney U-test. Statistical tests were also performed for hypoxia and perfusion parameters determined by the kinetic model and for two different metrics based on these parameters. Results The kinetic Fmiso analysis extracts local hypoxia and perfusion characteristics of a tumor tissue. These parameters are independent quantities. In this study, different types of characteristic hypoxia-perfusion patterns in tumors could be identified. The clinical verification of the results, obtained on the basis of the kinetic analysis, showed a high correlation of hypoxia-perfusion patterns and RT treatment outcome (p = 0.001) for this initial patient group. Conclusion The presented study established, that Fmiso PET scans may benefit from dynamic acquisition and analysis by a kinetic model. The pattern of distribution of perfusion and hypoxia in the tissue is correlated to local control in HNC.