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  • 1
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    German Medical Science GMS Publishing House; Düsseldorf
    In:  PTCOG 48; Meeting of the Particle Therapy Co-Operative Group; 20090928-20091003; Heidelberg; DOC09ptcog143 /20090924/
    Publication Date: 2009-09-25
    Keywords: ddc: 610
    Language: English
    Type: conferenceObject
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  • 2
  • 3
    Keywords: LUNG ; radiosurgery ; STEREOTACTIC RADIOSURGERY ; complication ; PART
    Type of Publication: Book chapter
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  • 4
  • 5
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    German Medical Science GMS Publishing House; Düsseldorf
    In:  GMS Infectious Diseases; VOL: 4; DOC03 /20160620/
    Publication Date: 2016-06-20
    Description: Mycotoxins are produced pre harvest by some molds and secreted into various food items of plant origin, such cereals, vegetables, spices, coffee and nuts. If the food items are not stored under adequate conditions, a post harvest contamination may also occur. Animals and humans take them up by food items and some of them are stored and accumulated in different tissues and organs, so that food of animal origin may be contaminated, too. Especially aflatoxin and ochratoxin are secreted into milk by consumers of contaminated food. Since milk represents the major food source of newborns and infants, they are notably exposed to these mycotoxins. This health risk for these individuals may be of particular importance, because their ability to metabolize these fungal toxic agents is not yet fully developed at this stage.
    Keywords: mycotoxins ; aflatoxin ; ochratoxin ; cow milk ; human breast milk ; ddc: 610
    Language: English
    Type: article
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  • 6
    Keywords: CANCER ; IRRADIATION ; radiotherapy ; tumor ; Germany ; LUNG ; THERAPY ; CT ; liver ; ACCURACY ; stereotactic ; CONFORMAL RADIOTHERAPY ; RADIATION-THERAPY ; ESCALATION ; MOTION ; TARGETS ; BREATH-HOLD TECHNIQUE ; IMMOBILIZATION ; TUMOR MOVEMENT ; multislice CT,lung tumors,stereotactic radiation therapy,respiratory movement
    Type of Publication: Journal article published
    PubMed ID: 14509953
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  • 7
    Keywords: CANCER ; IRRADIATION ; radiotherapy ; tumor ; carcinoma ; THERAPY ; RISK ; CONFORMAL RADIOTHERAPY ; EXPERIENCE ; head and neck ; IMRT ; ACCELERATED FRACTIONATION ; ADENOID CYSTIC CARCINOMA ; intensity modulated radiation therapy ; inverse treatment planning ; NASOPHARYNGEAL CARCINOMA ; PAROTID-GLAND ; SALIVARY-GLAND CARCINOMA
    Abstract: Purpose/Objective: The aim of this analysis is to evaluate the feasibility of inverse treatment planning and intensity modulated radiation therapy (IMRT) for head and neck cancer in daily clinical routine. A step and shoot IMRT approach was developed which allows the treatment of large target volumes without the need to use a split beam technique. By using the INIRT approach better protection of different organs at risk in the head and neck region may be achieved and an escalation of the dose in the tumor should be possible. We evaluated the feasibility of the treatment technique and the patient tolerance to the treatment. First clinical results are reported. Materials and Methods: Between 1999 and 2002, 48 patients with a carcinoma of the head and neck region were treated with curative intention. All patients were treated in a patient-specific Scotch-Cast mask. Patients who required treatment of the lymph node levels I-VI, were additionally positioned by a vacuum pillow in order to immobilize the upper part of the thorax. For inverse treatment planning, the software module KonRad was used which was integrated into the VIRTUOS planning system. Each treatment plan was verified using quantitative film dosimetry in a head and neck phantom. The step and shoot IMRT technique with a multileaf collimator integrated in a Primus (Siemens(R)) accelerator was used for treatment. For all target volumes the whole target including the lymph nodes were covered completely by the INIRT treatment. Results: The mean total dose for the target volumes of macroscopic disease ranged between 63.0 and 64.1 Gy. The mean total dose of microscopic disease ranged between 55.2 and 60.1 Gy. The mean percentage of planning target volume receiving 〈 90% of the prescribed dose ranged between 3.0 and 11.5%. For the treatment, the median number of beams was seven (range: five to nine). The time to deliver the treatment ranged between 9 and 18 min. The results of the verification revealed a mean deviation between measured and calculated absolute doses for the 48 patients of 0.1 +/- 1.4%. Including the phantom verification the IMRT treatment of the patients could be started approximately after five working days. The treatment was well tolerated by all patients. The 2-year actuarial overall survival was 92% and the 2-year actuarial local control rate was 93%. According to the Radiation Therapy Oncology Group (RTOG), no higher acute toxicity than Grade 3 was seen. Observation of the late effects revealed only one transient Grade 4 toxicity of the bone and only four patients had a xerostomia higher than Grade 1. Conclusion: The use of an inversely-planned and intensity-modulated step and shoot approach is feasible in clinical routine for head and neck tumors. Treatment could be applied as planned and no increased toxicity was found. Compared to other IMRT approaches for the head and neck region the used technique allows the treatment of the primary tumor and the lymph nodes level I-VI with only one intensity modulated treatment volume. The presented technique avoids to match conventional radiotherapy fields and INIRT fields, and therefore, reduce the risk of overdosage or underdosage at the matching line. Compared to conventional treatment techniques INIRT shows advantages in tumor dose and dose at the organs at risk. (C) 2003 Elsevier Science Ireland Ltd. All rights reserved
    Type of Publication: Journal article published
    PubMed ID: 12742271
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  • 8
    Keywords: brain ; CANCER ; IRRADIATION ; radiotherapy ; Germany ; MODEL ; FOLLOW-UP ; VOLUME ; incidence ; RISK ; TISSUE ; radiation ; PATIENT ; MECHANISM ; MR ; treatment ; magnetic resonance ; MAGNETIC-RESONANCE ; TARGET ; stereotactic ; radiosurgery ; RATES ; metastases ; CANCER-RESEARCH ; CURVES ; GAMMA-KNIFE RADIOSURGERY ; COMPLICATIONS ; MULTIVARIATE-ANALYSIS ; arteriovenous malformation ; ARTERIOVENOUS-MALFORMATION ; late radiation effects ; dose/volume response ; late radiation effect ; volume effect
    Abstract: Purpose: To evaluate late radiation effects in the brain after radiosurgery of patients with cerebral arteriovenous malformations (AVMs) and to quantify dose/volume-response relations for radiation-induced changes of brain tissue identified on follow-up neuroimaging. Patients and Methods: Data from 73 AVM patients who had stereotactic Linac radiosurgery at DKFZ (German Cancer Research Center), Heidelberg, Germany, were retrospectively analyzed. The endpoint of radiation-induced changes of brain tissue on follow-up magnetic resonance (MR) neuroimaging (i.e., edema and blood-brain-barrier breakdown [BBBB]) was evaluated. Each endpoint was further differentiated into three Levels with respect to the extent of the image change (small, intermediate, and Large). A previous analysis of the data found correlation of the endpoints with several dose/volume variables (DV) derived from each patient's dose distribution in the brain, including the mean dose in a volume of 20 cm(3) (Dmean(20)) and the absolute brain volume (including the AVM target) receiving a dose of at least 12 Gy (V12). To quantify dose/volume-response relations, patients were ranked according to DV (i.e., Dmean(20) and V12) and classified into four groups of equal size. For each group, the actuarial rates of developing the considered endpoints within 2.5 years after radiosurgery were determined from Kaplan-Meier estimates. The dose/volume-response curves were fitted with a sigmoid-shape Logistic function and characterized by DV50, the dose for a 50% incidence, and the slope parameter k. Results: Dose/volume-response relations, based on two alternative, but correlated, dose distribution variables that are a function of both dose and volume, were observed for radiation-induced changes of brain tissue. DV50 values of fitted dose/volume-response curves for tissue changes of Large extent (e.g., V12(50) = 22.0 +/- 2.6 cm(3) and Dmean20(50) =17.8 +/- 2.0 Gy for the combined endpoint of edema and/or BBBB) were significantly higher than those for small tissue changes (V12(50) = 4.0 0.3 cm(3) and Dmean20(50) 7.6 +/- 0.3 Gy). Conclusion: The derived dose/volume-response relations allow to quantitatively assess the risk of radiation-induced changes of brain tissue after radiosurgery in AVM patients. However, further understanding of the mechanism leading to brain tissue changes and their correlation with the desired obliteration is required. This knowledge will eventually help to optimize radiosurgical treatments in AVM patients
    Type of Publication: Journal article published
    PubMed ID: 15592695
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  • 9
    Keywords: brain ; radiotherapy ; Germany ; MODEL ; MODELS ; FOLLOW-UP ; INFORMATION ; VOLUME ; RISK ; TISSUE ; radiation ; PATIENT ; MECHANISM ; mechanisms ; TOLERANCE ; MRI ; treatment ; TARGET ; stereotactic ; radiosurgery ; NUMBER ; PARAMETERS ; PREDICTION ; treatment planning ; GAMMA-KNIFE RADIOSURGERY ; COMPLICATIONS ; MULTIVARIATE-ANALYSIS ; arteriovenous malformation ; ARTERIOVENOUS-MALFORMATION ; dose-volume parameter ; IMAGING CHANGES ; INTEGRATED LOGISTIC FORMULA ; late radiation effects ; LINEAR-ACCELERATOR RADIOSURGERY
    Abstract: Purpose: To investigate the correlation of radiation-induced changes of brain tissue after radiosurgery in patients with cerebral arteriovenous malformations (AVMs) with treatment planning and dose distribution parameters. Methods and Materials: The data from 73 AVM patients with complete follow-up information who underwent stereotactic linear accelerator radiosurgery at our institution between 1993 and 1998 were analyzed. Patients were treated with 11-14 noncoplanar fields shaped by a micromultileaf collimator. A median dose of 19 Gy (range, 13.3-22 Gy) was prescribed to the 80% isodose, which completely encompassed the target. Patients were followed at 3-month intervals the first year and then every 6 months with MRI and neurologic examinations. No patient developed radiation necrosis. The end point of radiation-induced tissue changes on follow-up neuroimaging (i.e., edema, blood-brain barrier breakdown [BBBB], and edema and/or BBBB combined) was evaluated. Each end point was further differentiated into four levels with respect to the extent of the image change (i.e., small, intermediate, large, and very large). The correlation. of each end point was investigated for several treatment planning parameters, including prescribed dose and the absolute size of the AVM target volume. In addition, a number of dose-volume variables were calculated from each patient's dose distribution in the brain, including the mean dose to a specified volume of 16 and 20 cm(3) that was given the highest dose (Dmean16 and Dmean20, respectively), and the absolute and percentage of brain volume (including the AVM target) receiving a dose of at least 8, 10, and 12 Gy (V8-V12, and V8(rel)-V12(rel), respectively). These parameters were also determined excluding the AVM target volume from the considered volume (subscript "excl"). The correlation of all treatment planning and dose-volume parameters with outcome was assessed in univariate Cox proportional hazards models. The results were assessed by p values (statistical significance for p less than or equal to0.05), residual deviance (ResDev) of the fits, and odds ratios. Results: The prescribed dose was not predictive of outcome (p 〉0.05 for all end points). The AVM target volume correlated significantly with large edema, as well as large edema and/or BBBB. V12 and Dmean20 were significantly associated with all end points, except very large edema and large BBBB. Patients with V12 of 27.6 cm(3) (Dmean20 of 18.9 Gy) had a 2.8-fold (fourfold) higher risk of developing edema and/or BBBB with large extent than those with V12 of 4.2 cm(3) (Dmean20 of 8.4 Gy). For all end points, V12(rel) correlated worse with outcome compared with V12 (e.g., end point of large edema and/or BBBB: ResDev = 85.8 and 86.5 for V12 and V12rel, respectively). Excluding the AVM target volume from the considered irradiated volume led to only small changes in the resulting correlations (e.g., end point of small edema and/or BBBB: ResDev = 99.0 and 98.7 for V12 and V12(excl), respectively, and ResDev = 96.1 and 96.1 for Dmean20 and Dmean20(excl), respectively). Throughout the analysis, V8-V12, Dmean20, and Dmean16 yielded similar results and none of these parameters could be favored over the others. Conclusion: Radiation-induced changes of brain tissue after AVM radiosurgery can be well predicted by single dose distribution parameters that are a function of both dose and volume. These can be used to quantify dose-volume response relations. Studies of this nature will eventually help to improve our current understanding of the mechanisms leading to radiation-induced tissue changes after AVM radiosurgery and to optimize radiosurgery treatment planning. (C) 2004 Elsevier Inc
    Type of Publication: Journal article published
    PubMed ID: 15183483
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  • 10
    Keywords: OPTIMIZATION ; CANCER ; GROWTH ; IRRADIATION ; radiotherapy ; SURVIVAL ; tumor ; Germany ; THERAPY ; FOLLOW-UP ; TUMORS ; SURGERY ; radiation ; PATIENT ; REDUCTION ; treatment ; hormone ; EXPERIENCE ; RADIATION-THERAPY ; PROGNOSTIC-FACTORS ; HEAD ; NECK ; SKULL BASE ; WHITE-MATTER ; ORGANIZATION ; CHONDROSARCOMA ; PROTON RADIATION-THERAPY ; ONCOLOGY ; GRADE ; CHORDOMAS ; INTERVAL ; methods ; carbon ion radiation therapy ; EXTRASKELETAL MYXOID CHONDROSARCOMA ; particle therapy
    Abstract: Purpose: To evaluate the effectiveness and toxicity of carbon ion radiotherapy in chondrosarcomas of the skull base. Patients and Methods: Between November 1998 and September 2005, 54 patients with low-grade and intermediate-grade chondrosarcomas of the skull base have been treated with carbon ion radiation therapy (RT) using the raster scan technique at the Gesellschaft fur Schwerionenforschung in Darmstadt, Germany. All patients had gross residual tumors after surgery. Median total dose was 60 CGE (weekly fractionation 7 X 3.0 CGE). All patients were followed prospectively in regular intervals after treatment. Local control and overall survival rates were calculated using the Kaplan-Meier method. Toxicity was assessed according to the Common Terminology Criteria (CTCAE v.3.0) and the Radiation Therapy Oncology Group (RTOG)/European Organization for Research and Treatment of Cancer (EORTC) score. Results: Median follow-up was 33 months (range, 3-84 months). Only 2 patients developed local recurrences. The actuarial local control rates were 96.2% and 89.8% at 3 and 4 years; overall survival was 98.2% at 5 years. Only I patient developed a mucositis CTCAE Grade 3; the remaining patients did not develop any acute toxicities 〉 CTCAE Grade 2. Five patients developed minor late toxicities (RTOG/EORTC Grades 1-2), including bilateral cataract (n=1), sensory hearing loss (n=1), a reduction of growth hormone (n=1), and asymptomatic radiation-induced white matter changes of the adjacent temporal lobe (n=2). Grade 3 late toxicity occurred in 1 patient (1.9%) only. Conclusions: Carbon ion RT is an effective treatment for low- and intermediate-grade chondrosarcomas of the skull base offering high local control rates with low toxicity. (c) 2007 Elsevier Inc
    Type of Publication: Journal article published
    PubMed ID: 17056193
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