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    Keywords: CANCER ; Germany ; LUNG ; THERAPY ; chest ; CT ; IMAGES ; imaging ; SYSTEM ; computed tomography ; NUCLEAR-MEDICINE ; TIME ; QUALITY ; MEMBRANE ; COMPUTED-TOMOGRAPHY ; SERIES ; MOTION ; ARTIFACTS ; nuclear medicine ; dynamic MRI ; HELICAL CT ; radiology ; ONCOLOGY ; RE ; EX-VIVO ; DIAPHRAGM ; methods ; PHASE ; NUCLEAR ; IMAGE QUALITY ; respiration ; lungs ; RESPIRATORY MOTION ; phantom ; tumor motion ; MEDICINE ; NOV ; comparison ; DETECTOR CT ; PORCINE LUNGS ; ex-vivo study ; GUIDED RADIOTHERAPY ; retrospective gating
    Abstract: Purpose: To analyse the image quality of retrospectively gated helical CT using controlled respiratory motion of porcine lung explants. Materials and methods: Five porcine lungs were examined inside a chest phantom. A silicone membrane was rhythmically inflated and deflated to simulate diaphragmatic respiration. Dynamic images (regular respiration at 8/min) and static scans (w/o respiration) at 0/25/50/75 and 100% of maximum inspiration were acquired with a 40-row detector CT scanner (rotation time 1 s, pitch 0.1). Image quality on multi-planar reformations was evaluated by two observers. Partial projection artifacts, step ladder-artifacts and noise were compared for upper, middle and lower parts of the lung and different respiratory phases (scores 0-3 for absent, minimal, moderate and diagnostically relevant artifacts). Results: Partial projection effects were limited to dynamic scans (mean score 1.33). Stepladder artifacts predominated in dynamic series compared to static series (mean score 0.55 versus 0.1; p 〈 0.001). Image noise was not related to lung motion (mean scores 0.68-0.81). All artifacts predominated close to the diaphragm compared to the upper and middle parts of the lung (p 〈 0.001 to p = 0.02, respectively). Partial projection and stepladder artifacts were less in end-inspiration and end-expiration than within the respiration (p 〈 0.001 and p = 0.17, respectively). Diagnostically relevant artifacts were noted 9 times (9/9 close to diaphragm, 7/9 partial-projection). Conclusions: Even in ideal realistic conditions, helical 4D-CT produced tolerable artifacts which could be overcome by radiologists. (c) 2007 Elsevier Ireland Ltd. All rights reserved
    Type of Publication: Journal article published
    PubMed ID: 17923161
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  • 3
    Keywords: brain ; radiotherapy ; SURVIVAL ; Germany ; THERAPY ; DIAGNOSIS ; FOLLOW-UP ; imaging ; VOLUME ; LONG-TERM ; POPULATION ; radiation ; TIME ; PATIENT ; IMPACT ; TARGET ; RADIATION-THERAPY ; AGE ; MALES ; RATES ; PROGNOSTIC-FACTORS ; RESECTION ; PROGNOSTIC FACTORS ; LOW-GRADE ASTROCYTOMAS ; CHILDREN ; MR imaging ; GLIOMAS ; THERAPIES ; GLIOMA ; radiation therapy ; fractionated stereotactic radiotherapy ; LOW-GRADE GLIOMA ; HIGH-GRADE GLIOMAS ; SYMPTOMS ; PEDIATRIC-ONCOLOGY-GROUP ; NERVOUS-SYSTEM TUMORS ; EXTENT ; GLIOBLASTOMA ; PHASE-I/II TRIAL ; PROGRESSION-FREE SURVIVAL ; outcome ; WELL ; BEAM IRRADIATION ; Brain stem gliomas ; HYPERFRACTIONATED RADIATION-THERAPY ; MEDICAL-CENTER ; PONTINE GLIOMAS
    Abstract: Introduction: To assess long-term outcome in 85 patients with brain stem gliomas treated with fractionated stereotactic radiation therapy (FSRT). Patient and methods: Thirty-nine patients were females, and 46 were males. Median age at primary diagnosis was 26 years. Thirty-one patients were younger than 18 years. Histopathological examination confirmed a low-grade glioma in 57 patients. Of the group of high-grade gliomas, six were anaplastic astrocytomas, and two were classified as glioblastoma. Patient and methods: Radiation therapy was performed as FSRT. The median target volume was 101 nil. We applied a median dose of 54 Gy in conventional fractionation of 1.8 Gy. In seven of 85 patients (8%) FSRT was performed as re-irradiation. Results: The median follow-up time was 42 months. Median overall survival (OS) was 81 months. OS rates were 77% at 12 months, 70% at 24 months, and 63% at 36 months. Significant impact on OS could be shown for pilocytic histology, age, neurosurgical resection as well as for the presence of cyst on MR-imaging. Results: Median progression-free survival (PFS) after FSRT was 52 months. PFS rates at 12 months were 70%, and 63% and 58% at 24 and 36 months. respectively. Results: Histology, partial neurosurgical resection and the duration of symptoms could be identified as significant prognostic factors. Conclusion: Long-term outcome of FSRT in patients with brain stem gliomas is acceptable with low rates of side effects. Significant impact on outcome could be shown for histology. age, extent of neurosurgical resection as well as for cyst formation. No dose-response relationship could be observed. (C) 2009 Elsevier Ireland Ltd. All rights reserved. Radiotherapy and Oncology 91 (2009) 60-66
    Type of Publication: Journal article published
    PubMed ID: 19285356
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  • 4
    Abstract: PURPOSE: To evaluate the outcomes of patients with vestibular schwannoma (VS) treated with fractionated stereotactic radiotherapy (FSRT) vs. those treated with stereotactic radiosurgery (SRS). METHODS AND MATERIALS: This study is based on an analysis of 200 patients with 202 VSs treated with FSRT (n = 172) or SRS (n = 30). Patients with tumor progression and/or progression of clinical symptoms were selected for treatment. In 165 out of 202 VSs (82%), RT was performed as the primary treatment for VS, and for 37 VSs (18%), RT was conducted for tumor progression after neurosurgical intervention. For patients receiving FSRT, a median total dose of 57.6 Gy was prescribed, with a median fractionation of 5 x 1.8 Gy per week. For patients who underwent SRS, a median single dose of 13 Gy was prescribed to the 80% isodose. RESULTS: FSRT and SRS were well tolerated. Median follow-up time was 75 months. Local control was not statistically different for both groups. The probability of maintaining the pretreatment hearing level after SRS with doses of 〈 or =13 Gy was comparable to that of FSRT. The radiation dose for the SRS group (〈 or =13 Gy vs. 〉13 Gy) significantly influenced hearing preservation rates (p = 0.03). In the group of patients treated with SRS doses of 〈 or =13 Gy, cranial nerve toxicity was comparable to that of the FSRT group. CONCLUSIONS: FSRT and SRS are both safe and effective alternatives for the treatment of VS. Local control rates are comparable in both groups. SRS with doses of 〈 or =13 Gy is a safe alternative to FSRT. While FSRT can be applied safely for the treatment of VSs of all sizes, SRS should be reserved for smaller lesions.
    Type of Publication: Journal article published
    PubMed ID: 19604653
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  • 5
    Keywords: IRRADIATION ; radiotherapy ; SYSTEM ; TUMORS ; TRIAL ; RADIATION-THERAPY ; SKULL-BASE ; temozolomide ; GLIOBLASTOMA ; ADENOID CYSTIC CARCINOMAS
    Abstract: PUROPOSE: To asses early toxicity and response in 118 patients treated with scanned ion beams to validate the safety of intensity-controlled raster scanning at the Heidelberg Ion Therapy Center. PATIENTS AND METHODS: Between November 2009 and June 2010, we treated 118 patients with proton and carbon ion radiotherapy (RT) using active beam delivery. The main indications included skull base chordomas and chondrosarcomas, salivary gland tumors, and gliomas. We evaluated early toxicity within 6 weeks after RT and the initial clinical and radiologic response for quality assurance in our new facility. RESULTS: In all 118 patients, few side effects were observed, in particular, no high numbers of severe acute toxicity were found. In general, the patients treated with particle therapy alone showed only a few single side effects, mainly Radiation Therapy Oncology Group/Common Terminology Criteria grade 1. The most frequent side effects and cumulative incidence of single side effects were observed in the head-and-neck patients treated with particle therapy as a boost and photon intensity-modulated RT. The toxicities included common radiation-attributed reactions known from photon RT, including mucositis, dysphagia, and skin erythema. The most predominant imaging responses were observed in patients with high-grade gliomas and those with salivary gland tumors. For skull base tumors, imaging showed a stable tumor outline in most patients. Thirteen patients showed improvement of pre-existing clinical symptoms. CONCLUSIONS: Side effects related to particle treatment were rare, and the overall tolerability of the treatment was shown. The initial response was promising. The data have confirmed the safe delivery of carbon ions and protons at the newly opened Heidelberg facility.
    Type of Publication: Journal article published
    PubMed ID: 21300464
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  • 6
    Keywords: EXPERIENCE ; RADIATION-THERAPY ; OUTCOMES ; CHILDREN ; MANAGEMENT ; ADULTS ; MORBIDITY ; COMBINED SURGERY ; CHILDHOOD CRANIOPHARYNGIOMA ; PEDIATRIC CRANIOPHARYNGIOMAS
    Abstract: PURPOSE: There are already numerous reports about high local control rates in patients with craniopharyngioma but there are only few studies with follow up times of more than 10 years. This study is an analysis of long term control, tumor response and side effects after fractionated stereotactic radiotherapy (FSRT) for patients with craniopharyngioma. PATIENTS AND METHODS: 55 patients who were treated with FSRT for craniopharyngioma were analyzed. Median age was 37 years (range 6-70 years), among them eight children 〈 18 years. Radiotherapy (RT) was indicated for progressive disease after neurosurgical resection or postoperatively after repeated resection or partial resection. A median dose of 52.2 Gy (50 - 57.6 Gy) was applied with typical dose per fraction of 1.8 Gy five times per week. The regular follow up examinations comprised in addition to contrast enhanced MRI scans thorough physical examinations and clinical evaluation. RESULTS: During median follow up of 128 months (2 - 276 months) local control rate was 95.3% after 5 years, 92.1% after 10 years and 88.1% after 20 years. Overall survival after 10 years was 83.3% and after 20 years 67.8% whereby none of the deaths were directly attributed to craniopharyngioma. Overall treatment was tolerated well with almost no severe acute or chronic side effects. One patient developed complete anosmia, another one's initially impaired vision deteriorated further. In 83.6% of the cases with radiological follow up a regression of irradiated tumor residues was monitored, in 7 cases complete response was achieved. 44 patients presented themselves initially with endocrinologic dysfunction none of them showed signs of further deterioration during follow up. No secondary malignancies were observed. CONCLUSION: Long term results for patients with craniopharyngioma after stereotactic radiotherapy are with respect to low treatment related side effects as well as to local control and overall survival excellent.
    Type of Publication: Journal article published
    PubMed ID: 25227427
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  • 7
    Keywords: radiotherapy ; TUMORS ; IMPACT ; MALIGNANCIES ; PROGNOSTIC-FACTORS ; CHILDREN ; CERVICAL-SPINE ; MANAGEMENT ; CHONDROSARCOMA ; PROTON RADIATION-THERAPY
    Abstract: BACKGROUNDThe current study was conducted to evaluate the long-term results of irradiation with carbon ions in a raster scanning technique in patients with skull base chordomas. METHODSBetween 1998 and 2008, a total of 155 patients (76 men and 79 women) with a median age of 48 years (range, 15 years-85 years) were irradiated with carbon ions using a raster scan technique. The irradiation was performed at the Society for Heavy Ion Research in Darmstadt, Germany. The median total dose was 60 gray (relative biological effectiveness) at 3 gray (relative biological effectiveness) per fraction. The median boost planning target volume was 70 mL (range, 2 mL-294 mL). Local control (LC) and overall survival (OS) were evaluated using the Kaplan-Meier method, whereas long-term toxicity was evaluated via questionnaires. RESULTSThe median follow-up was 72 months (range, 12 months-165 months). All patients had residual macroscopic tumors at the initiation of radiotherapy. The authors observed 55 local recurrences during follow-up, as well as systemic disease progression in 4 patients. The resulting 3-year, 5-year, and 10-year LC rates were 82%, 72%, and 54%, respectively, whereas the 3-year, 5-year, and 10-year OS rates were 95%, 85%, and 75%, respectively. Age 〈48 years and a boost volume 〉75 mL were associated with a significantly improved LC and OS. Primary treatment resulted in a significantly better OS probability. No higher late toxicity could be detected after carbon ion treatment. CONCLUSIONSCarbon ion therapy appears to be a safe and effective treatment for patients with skull base chordoma, resulting in high LC and OS rates.
    Type of Publication: Journal article published
    PubMed ID: 24948519
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  • 8
    Keywords: TRIAL ; VERIFICATION ; RADIATION-THERAPY ; MONTE-CARLO SIMULATIONS ; POSITRON-EMISSION-TOMOGRAPHY ; proton therapy ; ADJUVANT TEMOZOLOMIDE ; carbon ion radiotherapy ; GLIOBLASTOMA ; BEAM PET
    Abstract: PURPOSE: The physical and biological properties of ion-beams offer various advantages in comparison to conventional radiotherapy, though uncertainties concerning quality assurance are still left. Due to the inverted depth dose profile, range accuracy is of paramount importance. We investigated the range deviations between planning simulation and post-fractional PET/CT measurement from particle therapy in primary glioblastoma. METHODS AND MATERIALS: 20 patients with glioblastoma undergoing particle therapy at our institution were selected. 10 received a proton-boost, 10 a carbon-ion-boost in addition to standard treatment. After two fractions, we performed a PET/CT-scan of the brain. We compared the resulting range deviation based on the Most-likely-shift method between the two measurements, and the measurements with corresponding expectations, calculated with the Monte-Carlo code FLUKA. RESULTS: A patient's two measurements deviated by 0.7mm (+/-0.7mm). Overall comparison between measurements and simulation resulted in a mean range deviation of 3.3mm (+/-2.2mm) with significant lower deviations in the (12)C-arm. CONCLUSION: The used planning concepts display the actual dose distributions adequately. The carbon ion group's results are below the used PTV safety margins (3mm). Further adjustments to the simulation are required for proton irradiations. Some anatomical situations require particular attention to ensure highest accuracy and safety.
    Type of Publication: Journal article published
    PubMed ID: 25842968
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  • 9
    Keywords: radiotherapy ; SURVIVAL ; BREAST-CANCER ; RADIATION-THERAPY ; WAITING TIME ; CLINICAL-OUTCOMES ; CONCOMITANT ; GRADE III/IV GLIOMAS
    Abstract: BACKGROUND: The benefits of new innovations in glioblastoma therapies should not be curtailed as a result of delays in commencement of radiation therapy, caused by clinical circumstances as well as diagnostic procedures. This study evaluates whether delays in chemo-radiotherapy after surgery, while determining O6-methylguanine-DNA-methyltransferase (MGMT) promoter status, affect the survival rates of patients with glioblastoma (GBM). METHODS: Our sample comprised 50 GBM patients in a retrospective analysis of three prospective studies that focused on combined radiotherapy and required MGMT promoter-status testing as inclusion criteria. Results were compared with a reference group of 127 favourable GBM cases (Karnofsky performance-status scale 〉/= 70), in which the patients underwent standard postoperative chemo-radiotherapy with temozolomide. Survival time was calculated using the Kaplan-Meier method, and a multivariate analysis of the delays between surgical and radiotherapy procedures was performed using the Cox regression model. RESULTS: The study group's median overall survival time was 16.2 months (with a range of 2 to 56 months), versus the reference group's survival time of 18.2 months (with a range of 1 to 92 months) (p = 0.64). The delay between surgery and radiotherapy was increased by 8 days in the study patients (p 〈 0.001), with a median delay of 35 days (range: 18-49 days) corresponding to the typical 27-day delay (range: 5-98 days) for those in the reference group. Univariate and multivariate analyses did not show any negative association between survival time and delaying radiation therapy to determine MGMT-promoter status; commencement of radiation therapy sooner than 24 days after surgery was the threshold for significantly decreased overall survival (p = 0.01) and progression-free (p = 0.03) survival. CONCLUSION: Delaying postoperative chemoradiation for GBM patients-carried out in order to determine MGMT-promoter status-did not have a negative impact on survival time. Indeed, the data of the present study shows that initiating radiation therapy sooner than 24 days after surgery has a negative impact on progression and survival.
    Type of Publication: Journal article published
    PubMed ID: 26223282
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  • 10
    Abstract: PURPOSE: Locoregional control (LC) in malignant salivary gland tumors is dose-dependent, initial results with particle therapy were promising. We report our experience with raster-scanned, intensity-controlled carbon ion therapy (C12) and IMRT in 309 patients with pathologically confirmed adenoid cystic carcinoma (ACC) of the head and neck. PATIENTS AND METHODS: Treatment records of patients treated with C12 between 08/1998 and 05/2013 were evaluated regarding tumor stage, treatment, toxicity (CTCAE v3), LC, progression-free survival (PFS) and overall survival (OS). Response assessment was carried out according to RECIST1.1. RESULTS: Tumor stages were mostly advanced (T4a/b: 60%, macroscopic disease: 71%), most common sites of origin were the paranasal sinus (37%). At a median follow-up at 33.9months, LC, PFS, and OS at 3 and 5year estimates are 83.7%/58.5%, 67.8%/56.1%, and 88.9%/74.6%. LC correlates with T-stage but neither nodal stage, age, relapse state, nor margin status. RECIST did not correlate with LC or survival rates. CONCLUSION: IMRT plus C12 boost results in good control and survival rates at moderate toxicity. Margin status did not correlate with LC in T4 tumors, extensive and potentially mutilating surgical procedures may have to be re-evaluated. RECIST assessment did not correlate with either LC or survival rates; potentially more meaningful radiological parameters need to be developed.
    Type of Publication: Journal article published
    PubMed ID: 26164774
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