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  • 1
    Call number: YY Diss Hoes/Mag
    Keywords: DKFZ-publications / academic dissertations
    Pages: 41, 12 p. : ill.
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  • 2
  • 3
    Keywords: THERAPIES ; RADIATION-THERAPY ; THERAPY ; radiotherapy ; radiation ; INFORMATION
    Type of Publication: Book chapter
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  • 4
    Keywords: measurement ; radiotherapy ; Germany ; CT ; IMAGES ; ACCURACY ; RESOLUTION ; validation ; MRI ; SEQUENCE ; treatment ; MAGNETIC-RESONANCE ; TARGET ; stereotactic radiotherapy ; REQUIRES ; REGISTRATION ; LOCALIZATION ; positron emission tomography ; HEAD ; NECK ; SPECT ; treatment planning ; PET ; head and neck ; BRAIN IMAGES ; SPATIAL DISTORTION
    Abstract: CT, MRI, PET and SPECT provide complementary information for treatment planning in stereotactic radiotherapy. Stereotactic correlation of these images requires commissioning tests to confirm the localization accuracy of each modality. A phantom was developed to measure the accuracy of stereotactic localization for CT, MRI, PET and SPECT in the head and neck region. To this end, the stereotactically measured coordinates of structures within the phantom were compared with their mechanically defined coordinates. For MRI, PET and SPECT, measurements were performed using two different devices. For MRI, T1- and T2-weighted imaging sequences were applied. For each measurement, the mean radial deviation in space between the stereotactically measured and mechanically defined position of target points was determined. For CT, the mean radial deviation was 0.4 +/- 0.2 mm. For MRI, the mean deviations ranged between 0.7 +/- 0.2 mm and 1.4 +/- 0.5 rum, depending on the MRI device and the imaging sequence. For PET, mean deviations of 1.1 +/- 0.5 mm and 2.4 +/- 0.3. mm were obtained. The mean deviations for SPECT were 1.6 +/- 0.5 mm and 2.0 +/- 0.6 mm. The phantom is well suited to determine the accuracy of stereotactic localization with CT, MRI, PET and SPECT in the head and neck region. The obtained accuracy is well below the physical resolution for CT, PET and SPECT, and of comparable magnitude for MRI. Since the localization accuracy may be device dependent, results obtained at one device cannot be generalized to others
    Type of Publication: Journal article published
    PubMed ID: 12587905
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  • 5
    Keywords: CANCER ; IRRADIATION ; radiotherapy ; tumor ; Germany ; LUNG ; VOLUME ; MORTALITY ; TISSUE ; TUMORS ; SURGERY ; radiation ; PATIENT ; QUALITY ; treatment ; BREAST ; breast cancer ; BREAST-CANCER ; TARGET ; CANCER PATIENTS ; ADJUVANT ; IMRT ; COMPENSATION ; NODES ; BOOST ; SURVIVORS ; CONSERVING SURGERY ; IRRADIATION TECHNIQUE
    Abstract: The aim of this paper is to evaluate the benefit of inversely planned intensity modulated radiotherapy (IMRT) in the adjuvant irradiation of breast cancer when internal mammary lymph nodes are included in the treatment volume. 20 patients treated with 3D-planned conventional radiotherapy (CRT) following breast conserving surgery were included in the study. We chose 10 patients with left-sided and 10 patients with right-sided tumors. All treatment volumes included the internal mammary chain. For plan comparison to the applied CRT plan an inverse IMRT-plan in 'step-and-shoot'-technique was calculated.For all patients IMRT resulted in an improved conformity of dose distribution to the target volume compared to CRT (mean COIN95: 0.798 vs. 0.514) with COIN95 = C1 * C2 (C1= fraction of CTV that is covered by 〉 95% of the prescribed dose and C2 = volume of CTV that is covered by 〉 95% of the prescribed dose/total volume that is covered by 〉 95% of the prescribed dose). In all Gases with matching adjacent beams, the homogeneity in the target volume was improved. The volume of the ipsilateral lung irradiated with a dose higher than 20 Gy was reduced with IMRT from 24.6% to 13.1% compared to CRT For left-sided target volume the heart volume with a dose higher than 30 Gy was reduced from 6.2% to 0.2%.The presented plan comparison study for irradiation of the breast and the parasternal lymph nodes showed a substantial improvement of the dose distribution by inversely planned IMRT compared to CRT. This is visible for the target volume, the ipsilateral lung and, in case of left-sided target volume, the heart. Despite an increase in integral dose to the entire normal tissue, the application of IMRT might be clinically advantageous in cases where no satisfying dose distribution ran be obtained by CRT
    Type of Publication: Journal article published
    PubMed ID: 14750895
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  • 6
    Keywords: CANCER ; radiotherapy ; SURVIVAL ; tumor ; Germany ; TOXICITY ; FOLLOW-UP ; imaging ; DISEASE ; LONG-TERM ; SURGERY ; PATIENT ; RESPONSES ; MAGNETIC-RESONANCE ; magnetic resonance imaging ; TARGET ; NO ; stereotactic radiotherapy ; PROGRESSION ; MALIGNANCIES ; EXPERIENCE ; RADIATION-THERAPY ; TUMOR PROGRESSION ; EFFICACY ; RATES ; local control ; CHILDREN ; GLIOMAS ; MANAGEMENT ; MALIGNANCY ; ONCOLOGY ; CHILDHOOD ; RE ; CRANIOPHARYNGIOMAS ; development ; IMPAIRMENT ; methods ; fractionated stereotactic radiotherapy ; USA ; survival rate ; RESONANCE ; PRECISION ; COMBINED SURGERY ; Rathke pouch
    Abstract: BACKGROUND. The long-term outcome in patients with craniopharyngiomas treated with fractionated stereotactic radiotherapy (FSRT) was evaluated. METHODS. A total of 40 patients with craniopharyngiomas were treated between May 1989 and July 2006 with FSRT. Most patients were treated for tumor progression after surgery. A median target dose of 52.2 grays (Gy) (range, 50.4-56 Gy) was applied in a median conventional fractionation of 5 x 1.8 Gy per week. Follow-up examinations included thorough clinical assessment as well as contrast-enhanced magnetic resonance imaging scans. RESULTS. After a median follow-up of 98 months (range, 3-326 months), local control was 100% at both 5 years and 10 years. Overall survival rates at 5 years and 10 years were 97% and 139%, respectively. A complete response was observed in 4 patients and partial responses were noted in 25 patients. Eleven patients presented with stable disease during follow-up. Acute toxicity was mild in all patients. Long-term toxicity included enlargement of cysts requiring drainage 3 months after FSRT. No visual impairment, radionecrosis, or development of secondary malignancies were observed. CONCLUSIONS. The long-term outcome of FSRT for craniopharyngiomas is excellent with regard to local control as well as treatment-related side effects
    Type of Publication: Journal article published
    PubMed ID: 17469176
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  • 7
    Keywords: IRRADIATION ; radiotherapy ; tumor ; Germany ; THERAPY ; CT ; FOLLOW-UP ; VOLUME ; DISEASE ; liver ; NEW-YORK ; TUMORS ; radiation ; TIME ; PATIENT ; CONTRAST ; INJECTION ; treatment ; TYPE-1 ; stereotactic ; stereotactic radiotherapy ; MALIGNANCIES ; radiosurgery ; DECREASE ; RECURRENT ; TYPE-2 ; APPEARANCE ; INDUCED HEPATIC-INJURY ; normal tissue reaction ; RADIATION HEPATITIS ; veno-occlusive disease (VOD).
    Abstract: Purpose: To characterize and quantitatively assess focal radiation reactions in the liver after stereotactic single-dose radiotherapy for liver malignancies. Methods and Materials: A total of 131 multiphasic CT scans were performed in 36 patients before and after stereotactic radiotherapy for liver tumors. The examination protocol included a nonenhanced scan and contrast-enhanced scans at different times after contrast injection. The volume of the reaction was determined in each scan and the threshold dose calculated using the dose-volume histogram of the treatment plan. Results: Every patient showed a focal radiation reaction on at least one follow-up examination. In 74% of the posttherapeutic scans, a sharply demarcated hypodense area surrounded the treated tumor in the nonenhanced scans. The reaction occurred at a median of 1.8 months (range 1.2-4.6) after radiotherapy. The median threshold dose was 13.7 Gy (range 8.9=19.2). The threshold dose strongly correlated with the time of detection after therapy (r = 0.7). Radiologically, three reaction types were found on the enhanced scans: type 1, portal-venous phase: hypodense and late phase: isodense; type 2, portal-venous phase: hypodense and late phase: hyperdense; and type 3, portal-venous phase: isodense/hyperdense and late phase: hyperdense. Type 1 or 2 reactions were observed significantly earlier than type 3 (p 〈0.05). The median threshold dose for type 1 or 2 reactions was significantly lower than for type 3 (p 〈0.05). The reaction volume decreased with longer follow-up (2-4 months: median 40% of initial volume). The reaction types shifted with follow-up: 58% were of type 1 at the initial manifestation and 58% were of type 3 at the next examination thereafter. Conclusion: A focal radiation reaction occurs after stereotactic single-dose therapy in the liver. The volume of the reaction decreases and changes its radiologic appearance during follow-up. This reaction has to be differentiated from recurrent tumor. (C) 2003 Elsevier Inc
    Type of Publication: Journal article published
    PubMed ID: 12957256
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  • 8
    Keywords: CANCER ; IRRADIATION ; radiotherapy ; tumor ; COMBINATION ; evaluation ; Germany ; PROSTATE ; THERAPY ; CT ; VOLUME ; NEW-YORK ; RISK ; PATIENT ; primary ; QUALITY ; IONS ; treatment ; TARGET ; CONFORMAL RADIOTHERAPY ; EXPERIENCE ; DIFFERENCE ; PROSTATE-CANCER ; BLADDER ; ESCALATION ; INTENSITY-MODULATED RADIOTHERAPY ; treatment planning ; MOTION ; ORGAN MOTION ; TARGET COVERAGE ; CONFORMAL RADIATION-THERAPY ; DOSE-VOLUME HISTOGRAMS ; EXTERNAL-BEAM RADIOTHERAPY ; prostate cancer,carbon ion therapy,internal organ motion ; RECTAL BALLOON ; TECHNICAL ASPECTS
    Abstract: Purpose: To investigate the feasibility of raster scanned heavy charged particle therapy in the treatment of prostate cancer (PCa,) with special regard to the influence of internal organ motion on the dose distribution.Methods and Materials: The CT data of 8 patients with PCa who underwent three-dimensional conformal radiotherapy (RT) were chosen. In addition to the routine treatment planning scan, three to five additional positioning control CT scans were performed. The organs at risk and the target volumes were defined on all CT scans. Primary and boost carbon ion plans were calculated to deliver 66 Gy to the clinical target volume/planning target volume, with an additional 10 Gy to the gross tumor volume (GTV). To estimate the influence of internal organ motion on plan quality, the dose was recalculated on the basis of the control CT scans. The comparative analysis was based on the dose-volume histogram-derived physical parameters.Results: The average 90% target coverage was 99.1% for the GTV. The maximal dose to the rectum was 71.8 Gy. The average rectal mean dose was 19 Gy. The volume of the rectum receiving 70 and 68 Gy was 0.1 and 0.3 cm(3). The average difference in the 90% coverage for the GTV on control CT cubes was 3.6%. The maximal rectal dose increased to 76.2 Gy. The deviation in the mean rectal dose was 〈1 Gy on average. The rectal volume receiving 70 and 68 Gy increased to 2.5 and 3.3 cm(3).Conclusion: The investigation demonstrated the feasibility of raster scanned carbon ions for PCa RT. Excellent coverage of the target volume and optimal sparing of the rectum were acquired. The combination of photon intensity-modulated RT and a carbon ion boost to the GTV is the most rational solution for the gain of clinical experience in heavy ion RT for PCa patients. (C) 2004 Elsevier Inc
    Type of Publication: Journal article published
    PubMed ID: 14697425
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  • 9
    Keywords: CANCER ; IRRADIATION ; radiotherapy ; SURVIVAL ; Germany ; LUNG ; THERAPY ; TOXICITY ; lung cancer ; LUNG-CANCER ; SURGERY ; radiation ; PATIENT ; CYCLE ; treatment ; antibodies ; antibody ; STAGE ; TRIAL ; RADIATION-THERAPY ; RATES ; metastases ; chemotherapy ; RESECTION ; CARCINOMAS ; OVEREXPRESSION ; IMRT ; FEASIBILITY ; PHASE-II ; NECK-CANCER ; SUBSET ; CONCURRENT ; ADVANCED HEAD ; INFUSION ; PHASE ; REMISSION ; prospective ; NSCLC ; C225 ; FACTOR RECEPTOR BLOCKADE ; stage III ; surgical resection
    Abstract: Background: Even today, treatment of Stage III NSCLC still poses a serious challenge. So far, surgical resection is the treatment of choice. Patients whose tumour is not resectable or who are unfit to undergo surgery are usually referred to a combined radio-chemotherapy. However, combined radio-chemotherapeutic treatment is also associated with sometimes marked side effects but has been shown to be more efficient than radiation therapy alone. Nevertheless, there is a significant subset of patients whose overall condition does not permit administration of chemotherapy in a combined-modality treatment. It could be demonstrated though, that NSCLCs often exhibit over-expression of EGF-receptors hence providing an excellent target for the monoclonal EGFR-antagonist cetuximab (Erbitux(R)) which has already been shown to be effective in colorectal as well as head-and-neck tumours with comparatively mild side-effects. Methods/design: The NEAR trial is a prospective phase II feasibility study combining a monoclonal EGF-receptor antibody with loco-regional irradiation in patients with stage III NSCLC. This trial aims at testing the combination's efficacy and rate of development of distant metastases with an accrual of 30 patients. Patients receive weekly infusions of cetuximab (Erbitux(R)) plus loco-regional radiation therapy as intensity-modulated radiation therapy. After conclusion of radiation treatment patients continue to receive weekly cetuximab for 13 more cycles. Discussion: The primary objective of the NEAR trial is to evaluate toxicities and feasibility of the combined treatment with cetuximab (Erbitux(R)) and IMRT loco-regional irradiation. Secondary objectives are remission rates, 3-year-survival and local/systemic progression-free survival
    Type of Publication: Journal article published
    PubMed ID: 16681848
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  • 10
    Keywords: RECEPTOR ; ANGIOGENESIS ; EXPRESSION ; radiotherapy ; tumor ; Germany ; CT ; IMAGES ; imaging ; VOLUME ; DISEASE ; meningioma ; TUMORS ; radiation ; PATIENT ; MRI ; treatment ; MAGNETIC-RESONANCE ; magnetic resonance imaging ; RADIATION-THERAPY ; RESECTION ; positron emission tomography ; POSITRON-EMISSION-TOMOGRAPHY ; GLUCOSE ; COMPUTED-TOMOGRAPHY ; PET ; SOMATOSTATIN ; CONTRAST-ENHANCED MRI ; ORGANIZATION ; MANAGEMENT ; METHIONINE ; GRADE ; SOMATOSTATIN ANALOG ; SOMATOSTATIN RECEPTORS ; ANALOG ; SIZE ; HISTOLOGY ; intracranial meningioma ; SCANS ; ADJACENT ; fractionated stereotactic radiotherapy (FSRT) ; target volume definition ; [Ga-68]-DOTATOC
    Abstract: Purpose: To evaluate the influence of (68)-Ga-labeled DOTA ((0))-D-Phe ((1))-Tyr ((3))-Octreotide positron emission tomography ([Ga-68]-DOTATOC-PET) for target definition for fractionated stereotactic radiotherapy (FSRT) as a complementary modality to computed tomography (CT) and magnetic resonance imaging (MRI). Because meningiomas show a high expression of somatostatin receptor subtype 2, somatostatin analogs such as DOTATOC offer the possibility of receptor-targeted imaging. Patients and Methods: Twenty-six patients received stereotactic CT, MRI, and [Ga-68]-DOTATOC-PET as part of their treatment planning. Histology was: World Health Organization (WHO) Grade 161.5%, WHO Grade 2 7.7%, WHO Grade 3 3.9%, and undetermined 26.9%. Six patients received radiotherapy as primary treatment, 2 after subtotal resection; 17 patients were treated for recurrent disease. Dynamic PET scans were acquired before radiotherapy over 60 min after intravenous injection of 156 +/- 29 MBq [Ga-68]-DOTATOC. These PET images were imported in the planning software for FSRT. Planning target volume (PTV)-I outlined on CT and contrast-enhanced MRI was compared with PTV-II outlined on PET. PTV-III was defined with CT, MRI, and PET and was actually used for radiotherapy treatment. Results: PTV-III was smaller than PTV-I in 9 patients, the same size in 7 patients, and larger in 10 patients. Median PTV-I was 49.6 cc, median PTV-III was 57.2 cc. In all patients [Ga-68]-DOTATOC-PET delivered additional information concerning tumor extension. PTV-III was significantly modified based on DOTATOC-PET data in 19 patients. In 1 patient no tumor was exactly identified on CT/MRI but was visible on PET. Conclusion: These data demonstrate that [Ga-68]-DOTATOC-PET improves target definition for FSRT in patients with intracranial meningiomas. Radiation targeting with fused DOTATOC-PET, CT, and MRI resulted in significant alterations in target definition in 73%. (c) 2006 Elsevier Inc
    Type of Publication: Journal article published
    PubMed ID: 16488553
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