67 research outputs found

    Proton and carbon ion radiotherapy for primary brain tumors delivered with active raster scanning at the Heidelberg Ion Therapy Center (HIT): early treatment results and study concepts

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    <p>Abstract</p> <p>Background</p> <p>Particle irradiation was established at the University of Heidelberg 2 years ago. To date, more than 400 patients have been treated including patients with primary brain tumors. In malignant glioma (WHO IV) patients, two clinical trials have been set up-one investigating the benefit of a carbon ion (18 GyE) vs. a proton boost (10 GyE) in addition to photon radiotherapy (50 Gy), the other one investigating reirradiation with escalating total dose schedules starting at 30 GyE. In atypical meningioma patients (WHO °II), a carbon ion boost of 18 GyE is applied to macroscopic tumor residues following previous photon irradiation with 50 Gy.</p> <p>This study was set up in order to investigate toxicity and response after proton and carbon ion therapy for gliomas and meningiomas.</p> <p>Methods</p> <p>33 patients with gliomas (n = 26) and meningiomas (n = 7) were treated with carbon ion (n = 26) and proton (n = 7) radiotherapy. In 22 patients, particle irradiation was combined with photon therapy. Temozolomide-based chemotherapy was combined with particle therapy in 17 patients with gliomas. Particle therapy as reirradiation was conducted in 7 patients. Target volume definition was based upon CT, MRI and PET imaging. Response was assessed by MRI examinations, and progression was diagnosed according to the Macdonald criteria. Toxicity was classified according to CTCAE v4.0.</p> <p>Results</p> <p>Treatment was completed and tolerated well in all patients. Toxicity was moderate and included fatigue (24.2%), intermittent cranial nerve symptoms (6%) and single episodes of seizures (6%). At first and second follow-up examinations, mean maximum tumor diameters had slightly decreased from 29.7 mm to 27.1 mm and 24.9 mm respectively. Nine glioma patients suffered from tumor relapse, among these 5 with infield relapses, causing death in 8 patients. There was no progression in any meningioma patient.</p> <p>Conclusions</p> <p>Particle radiotherapy is safe and feasible in patients with primary brain tumors. It is associated with little toxicity. A positive response of both gliomas and meningiomas, which is suggested in these preliminary data, must be evaluated in further clinical trials.</p

    Quantitative assessment of inter-observer variability in target volume delineation on stereotactic radiotherapy treatment for pituitary adenoma and meningioma near optic tract

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    <p>Abstract</p> <p>Background</p> <p>To assess inter-observer variability in delineating target volume and organs at risk in benign tumor adjacent to optic tract as a quality assurance exercise.</p> <p>Methods</p> <p>We quantitatively analyzed 21 plans made by 11 clinicians in seven CyberKnife centers. The clinicians were provided with a raw data set (pituitary adenoma and meningioma) including clinical information, and were asked to delineate the lesions and create a treatment plan. Their contouring and plans (10 adenoma and 11 meningioma plans), were then compared. In addition, we estimated the influence of differences in contouring by superimposing the respective contours onto a default plan.</p> <p>Results</p> <p>The median planning target volume (PTV) and the ratio of the largest to the smallest contoured volume were 9.22 cm<sup>3 </sup>(range, 7.17 - 14.3 cm<sup>3</sup>) and 1.99 for pituitary adenoma, and 6.86 cm<sup>3 </sup>(range 6.05 - 14.6 cm<sup>3</sup>) and 2.41 for meningioma. PTV volume was 10.1 ± 1.74 cm<sup>3 </sup>for group 1 with a margin of 1 -2 mm around the CTV (n = 3) and 9.28 ± 1.8 cm<sup>3</sup>(p = 0.51) for group 2 with no margin (n = 7) in pituitary adenoma. In meningioma, group 1 showed larger PTV volume (10.1 ± 3.26 cm<sup>3</sup>) than group 2 (6.91 ± 0.7 cm<sup>3</sup>, p = 0.03). All submitted plan keep the irradiated dose to optic tract within the range of 50 Gy (equivalent total doses in 2 Gy fractionation). However, contours superimposed onto the dose distribution of the default plan indicated that an excessive dose 23.64 Gy (up to 268% of the default plan) in pituitary adenoma and 24.84 Gy (131% of the default plan) in meningioma to the optic nerve in the contours from different contouring.</p> <p>Conclusion</p> <p>Quality assurance revealed inter-observer variability in contour delineation and their influences on planning for pituitary adenoma and meningioma near optic tract.</p

    Treatment of patients with atypical meningiomas Simpson grade 4 and 5 with a carbon ion boost in combination with postoperative photon radiotherapy: The MARCIE Trial

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    <p>Abstract</p> <p>Background</p> <p>Treatment standard for patients with atypical or anaplastic meningioma is neurosurgical resection. With this approach, local control ranges between 50% and 70%, depending on resection status. A series or smaller studies has shown that postoperative radiotherapy in this patient population can increase progression-free survival, which translates into increased overall survival. However, meningiomas are known to be radioresistant tumors, and radiation doses of 60 Gy or higher have been shown to be necessary for tumor control.</p> <p>Carbon ions offer physical and biological characteristics. Due to their inverted dose profile and the high local dose deposition within the Bragg peak precise dose application and sparing of normal tissue is possible. Moreover, in comparison to photons, carbon ions offer an increased relative biological effectiveness (RBE), which can be calculated between 2 and 5 depending on the cell line as well as the endpoint analyzed.</p> <p>First data obtained within the Phase I/II trial performed at GSI in Darmstadt on carbon ion radiotherapy for patients with high-risk meningiomas has shown safety, and treatment results are promising.</p> <p>Methods/design</p> <p>The Phase II-MARCIE-Study will evaluate a carbon ion boost applied to the macroscopic tumor in conjunction with photon radiotherapy in patients with atypical menigiomas after incomplete resection or biopsy.</p> <p>Primary endpoint is progression-free survival, secondary endpoints are overall survival, safety and toxicity.</p> <p>Discussion</p> <p>Based on published data on the treatment of atypical meningiomas with carbon ions at GSI, the present study will evaluate this treatment concept in a larger patient population and will compare outcome to current standard photon treatment.</p> <p>Trial registration</p> <p>NCT01166321</p

    Magnetic resonance imaging, computed tomography, and 68Ga-DOTATOC positron emission tomography for imaging skull base meningiomas with infracranial extension treated with stereotactic radiotherapy - a case series

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    <p>Abstract</p> <p>Introduction</p> <p>Magnetic resonance imaging (MRI) and computed tomography (CT) with <sup>68</sup>Ga-DOTATOC positron emission tomography (<sup>68</sup>Ga-DOTATOC-PET) were compared retrospectively for their ability to delineate infracranial extension of skull base (SB) meningiomas treated with fractionated stereotactic radiotherapy.</p> <p>Methods</p> <p>Fifty patients with 56 meningiomas of the SB underwent MRI, CT, and <sup>68</sup>Ga-DOTATOC PET/CT prior to fractionated stereotactic radiotherapy. The study group consisted of 16 patients who had infracranial meningioma extension, visible on MRI ± CT (MRI/CT) <it>or </it>PET, and were evaluated further. The respective findings were reviewed independently, analyzed with respect to correlations, and compared with each other.</p> <p>Results</p> <p>Within the study group, SB transgression was associated with bony changes visible by CT in 14 patients (81%). Tumorous changes of the foramen ovale and rotundum were evident in 13 and 8 cases, respectively, which were accompanied by skeletal muscular invasion in 8 lesions. We analysed six designated anatomical sites of the SB in each of the 16 patients. Of the 96 sites, 42 had infiltration that was delineable by MRI/CT and PET in 35 cases and by PET only in 7 cases. The mean infracranial volume that was delineable in PET was 10.1 ± 10.6 cm<sup>3</sup>, which was somewhat larger than the volume detectable in MRI/CT (8.4 ± 7.9 cm<sup>3</sup>).</p> <p>Conclusions</p> <p><sup>68</sup>Ga-DOTATOC-PET allows detection and assessment of the extent of infracranial meningioma invasion. This method seems to be useful for planning fractionated stereotactic radiation when used in addition to conventional imaging modalities that are often inconclusive in the SB region.</p

    Adjuvant or radical fractionated stereotactic radiotherapy for patients with pituitary functional and nonfunctional macroadenoma

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    Purpose: To evaluate the efficacy and toxicity of stereotactic fractionated radiotherapy (SFRT) for patients with pituitary macroadenoma (PMA).Methods and Materials: Between March 2000 and March 2009, 27 patients (male to female ratio, 1.25) with PMA underwent SFRT (median dose, 50.4 Gy). Mean age of the patients was 56.5 years (range, 20.3 - 77.4). In all but one patient, SFRT was administered for salvage treatment after surgical resection (transphenoidal resection in 23, transphenoidal resection followed by craniotomy in 2 and multiple transphenoidal resections in another patient). In 10 (37%) patients, the PMAs were functional (3 ACTH-secreting, 3 prolactinomas, 2 growth hormone-secreting and 2 multiple hormone-secretion). Three (11.1%) and 9 (33.3%) patients had PMA abutting and compressing the optic chiasm, respectively. Mean tumor volume was 2.9 +/- 4.6 cm(3). Eighteen (66.7%) patients had hypopituitarism prior to SFRT. The mean follow-up period after SFRT was 72.4 +/- 37.2 months.Results: Tumor size decreased for 6 (22.2%) patients and remained unchanged for 19 (70.4%) other patients. Two (7.4%) patients had tumor growth inside the prescribed treatment volume. The estimated 5-year tumor growth control was 95.5% after SFRT. Biochemical remission occurred in 3 (30%) patients with functional PMA. Two patients with normal anterior pituitary function before SFRT developed new deficits 25 and 65 months after treatment. The 5-year survival without new anterior pituitary deficit was thus 95.8%. Five patients with visual field defect had improved visual function and 1 patient with no visual defect prior to SFRT, but an optic chiasm abutting tumor, had a decline in visual function. The estimated 5-year vision and pituitary function preservation rates were 93.2% and 95.8%, respectively.Conclusions: SFRT is a safe and effective treatment for patients with PMA, although longer follow-up is needed to evaluate long-term outcomes. In this study, approximately 1 patient with visual field defect out of two had an improved visual
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