scholarly journals High-dose hypofractionated pencil beam scanning carbon ion radiotherapy for lung tumors: Dosimetric impact of different spot sizes and robustness to interfractional uncertainties

2021 ◽  
Vol 85 ◽  
pp. 79-86
Author(s):  
Edoardo Mastella ◽  
Alfredo Mirandola ◽  
Stefania Russo ◽  
Alessandro Vai ◽  
Giuseppe Magro ◽  
...  
Keyword(s):  
Lung Tumors ◽  
Carbon Ion Radiotherapy ◽  
High Dose ◽  
Pencil Beam ◽  
Beam Scanning ◽  
Carbon Ion ◽  
Pencil Beam Scanning

scholarly journals Commissioning of a clinical pencil beam scanning proton therapy unit for ultra‐high dose rates (FLASH)

2021 ◽  
Author(s):  
Konrad P. Nesteruk ◽  
Michele Togno ◽  
Martin Grossmann ◽  
Anthony J. Lomax ◽  
Damien C. Weber ◽  
...  
Keyword(s):  
Proton Therapy ◽  
High Dose ◽  
Pencil Beam ◽  
Beam Scanning ◽  
Dose Rates ◽  
Pencil Beam Scanning

Commissioning of a fluoroscopic‐based real‐time markerless tumor tracking system in a superconducting rotating gantry for carbon‐ion pencil beam scanning treatment

2019 ◽  
Vol 46 (4) ◽  
pp. 1561-1574 ◽  
Author(s):  
Shinichiro Mori ◽  
Yukinobu Sakata ◽  
Ryusuke Hirai ◽  
Wataru Furuichi ◽  
Kazuki Shimabukuro ◽  
...  
Keyword(s):  
Real Time ◽  
Tracking System ◽  
Pencil Beam ◽  
Beam Scanning ◽  
Carbon Ion ◽  
Pencil Beam Scanning ◽  
Tumor Tracking

scholarly journals FLASH Proton Pencil Beam Scanning Irradiation Minimizes Radiation-Induced Leg Contracture and Skin Toxicity in Mice

Cancers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 1012
Author(s):  
Shannon Cunningham ◽  
Shelby McCauley ◽  
Kanimozhi Vairamani ◽  
Joseph Speth ◽  
Swati Girdhani ◽  
...  
Keyword(s):  
Soft Tissue ◽  
Proton Beam ◽  
Skin Toxicity ◽  
Tumor Control ◽  
High Dose ◽  
Pencil Beam ◽  
Beam Scanning ◽  
Dose Rates ◽  
Pencil Beam Scanning ◽  
Tgf Β1

Ultra-high dose rate radiation has been reported to produce a more favorable toxicity and tumor control profile compared to conventional dose rates that are used for patient treatment. So far, the so-called FLASH effect has been validated for electron, photon and scattered proton beam, but not yet for proton pencil beam scanning (PBS). Because PBS is the state-of-the-art delivery modality for proton therapy and constitutes a wide and growing installation base, we determined the benefit of FLASH PBS on skin and soft tissue toxicity. Using a pencil beam scanning nozzle and the plateau region of a 250 MeV proton beam, a uniform physical dose of 35 Gy (toxicity study) or 15 Gy (tumor control study) was delivered to the right hind leg of mice at various dose rates: Sham, Conventional (Conv, 1 Gy/s), Flash60 (57 Gy/s) and Flash115 (115 Gy/s). Acute radiation effects were quantified by measurements of plasma and skin levels of TGF-β1 and skin toxicity scoring. Delayed irradiation response was defined by hind leg contracture as a surrogate of irradiation-induced skin and soft tissue toxicity and by plasma levels of 13 different cytokines (CXCL1, CXCL10, Eotaxin, IL1-beta, IL-6, MCP-1, Mip1alpha, TNF-alpha, TNF-beta, VEGF, G-CSF, GM-CSF and TGF- β1). Plasma and skin levels of TGF-β1, skin toxicity and leg contracture were all significantly decreased in FLASH compared to Conv groups of mice. FLASH and Conv PBS had similar efficacy with regards to growth control of MOC1 and MOC2 head and neck cancer cells transplanted into syngeneic, immunocompetent mice. These results demonstrate consistent delivery of FLASH PBS radiation from 1 to 115 Gy/s in a clinical gantry. Radiation response following delivery of 35 Gy indicates potential benefits of FLASH versus conventional PBS that are related to skin and soft tissue toxicity.

Conformity and robustness of gated rescanned carbon ion pencil beam scanning of liver tumors at NIRS

2014 ◽  
Vol 111 (3) ◽  
pp. 431-436 ◽  
Author(s):  
Shinichiro Mori ◽  
Silvan Zenklusen ◽  
Taku Inaniwa ◽  
Takuji Furukawa ◽  
Hiroshi Imada ◽  
...  
Keyword(s):  
Liver Tumors ◽  
Pencil Beam ◽  
Beam Scanning ◽  
Carbon Ion ◽  
Pencil Beam Scanning

scholarly journals Dosimetric comparison of protons vs photons in re-irradiation of intracranial meningioma

2019 ◽  
Vol 92 (1100) ◽  
pp. 20190113
Author(s):  
Robert Poel ◽  
Anja Stuessi Lobmaier ◽  
Nicolaus Andratschke ◽  
Jan Unkelbach ◽  
Stephanie Tanadini-Lang ◽  
...  
Keyword(s):  
Treatment Modality ◽  
Volumetric Modulated Arc Therapy ◽  
Optimal Treatment ◽  
Intracranial Meningioma ◽  
High Dose ◽  
Pencil Beam ◽  
Beam Scanning ◽  
Pencil Beam Scanning ◽  
Arc Therapy ◽  
Dose Volumes

Objectives: Re-irradiation of recurrent intracranial meningiomas represents a major challenge due to dose limits of critical structures and the necessity of sufficient dose coverage of the recurrent tumor for local control. The aim of this study was to investigate dosimetric differences between pencil beam scanning protons (PBS) and volumetric modulated arc therapy (VMAT) photons for intracranial re-irradiation of meningiomas. Methods: Nine patients who received an initial dose >50 Gy for intracranial meningioma and who were re-irradiated for recurrence were selected for plan comparison. A volumetric modulated arc therapy photon and a pencil beam scanning proton plan were generated (prescription dose: 15 × 3 Gy) based on the targets used in the re-irradiation treatment. Results: In all cases, where the cumulative dose exceeded 100 or 90 Gy, these high dose volumes were larger for the proton plans. The integral doses were significantly higher in all photon plans (reduction with protons: 48.6%, p < 0.01). In two cases (22.2%), organ at risk (OAR) sparing was superior with the proton plan. In one case (11.1%), the photon plan showed a dosimetric advantage. In the remaining six cases (66.7%), we found no clinically relevant differences in dose to the OARs. Conclusions: The dosimetric results of the accumulated dose for a re-irradiation with protons and with photons were very similar. The photon plans had a steeper dose falloff directly outside the target and were superior in minimizing the high dose volumes. The proton plans achieved a lower integral dose. Clinically relevant OAR sparing was extremely case specific. The optimal treatment modality should be assessed individually. Advances in knowledge: Dose sparing in re-irradiation of intracranial meningiomas with protons or photons is highly case specific and the optimal treatment modality needs to be assessed on an individual basis.

Robustness of the Voluntary Breath-Hold Approach for the Treatment of Peripheral Lung Tumors Using Hypofractionated Pencil Beam Scanning Proton Therapy

2016 ◽  
Vol 95 (1) ◽  
pp. 534-541 ◽  
Author(s):  
Jenny Dueck ◽  
Antje-Christin Knopf ◽  
Antony Lomax ◽  
Francesca Albertini ◽  
Gitte F. Persson ◽  
...  
Keyword(s):  
Proton Therapy ◽  
Lung Tumors ◽  
Breath Hold ◽  
Pencil Beam ◽  
Beam Scanning ◽  
Pencil Beam Scanning ◽  
Peripheral Lung

scholarly journals Prognostic factors for spinal chordomas and chondrosarcomas treated with postoperative pencil-beam scanning proton therapy: a large, single-institution experience

2020 ◽  
Vol 32 (6) ◽  
pp. 921-930
Author(s):  
Fritz R. Murray ◽  
James W. Snider ◽  
Ralf A. Schneider ◽  
Marc Walser ◽  
Alessandra Bolsi ◽  
...  
Keyword(s):  
Prognostic Factors ◽  
Proton Therapy ◽  
Tumor Control ◽  
High Dose ◽  
Low Grade ◽  
Pencil Beam ◽  
Beam Scanning ◽  
En Bloc ◽  
Pencil Beam Scanning

OBJECTIVEThe aim of this paper was to evaluate the prognostic factors in surgical and adjuvant care for spinal chordomas and chondrosarcomas after surgery followed by high-dose pencil-beam scanning proton therapy (PBS-PT).METHODSFrom 1997 to 2016, 155 patients (61 female patients; median age 55 years) with spinal (cervical, n = 61; thoracic, n = 29; lumbar, n = 13; sacral, n = 46; pelvic, n = 6) classic chordomas (n = 116) and chondrosarcomas (n = 39; most were low grade) were treated with maximal safe resection followed by PBS-PT (median dose prescribed: 74 Gy [relative biological effectiveness], range 48.6–77 Gy). The majority of patients (n = 153, 98.7%) had undergone at least 1 resection prior to PBS-PT (median 1, range 0–5; biopsy only, n = 2). Fewer than half (45.1%) of the surgeries were rated as gross-total resections (GTRs) prior to PBS-PT. Surgical stabilization (SS) was present in 39% of all patients (n = 60). Ninety-one patients (59%) presented with macroscopic tumor at the start of PBS-PT. The median follow-up duration was 64.7 months (range 12.2–204.8 months).RESULTSThe 5-year local tumor control, disease-free survival (DFS), and overall survival were 64.9% (95% CI 56.3%–73.5%), 59.4% (95% CI 50.6%–68.2%), and 77.9% (95% CI 70.6%–85.2%), respectively. In total, 63 patients (40.6%) experienced failure during the follow-up period: local only in 32 (20.6%), distal only in 7 (4.5%), local + distal in 19 (12.3%), surgical pathway failure (SPF) only in 2 (1.3%), local + SPF in 2 (1.3%), and distal + SPF in 1 (< 1%). Univariate analysis identified gross residual disease, the presence of SS, and treatment era prior to 2008 as highly significant for worse outcome, with all 3 remaining significant on multivariate analysis. The type of surgery (GTR or subtotal resection/biopsy) and whether GTR was achieved by en bloc or curettage did not show a significant prognostic effect. Surgical complications prior to PBS-PT were present in 42.5% of all surgically treated patients and were seen more commonly in patients with multiple surgical interventions (p = 0.005) and those operated on with the intent of en bloc resection (p = 0.006).CONCLUSIONSThe extent of resection and metallic stabilization substantially influenced clinical outcomes for patients with spinal chordoma or chondrosarcoma despite high-dose adjuvant PBS-PT. Optimal upfront surgical management of these tumors continues to include GTR, as possible, with prompt adjuvant proton therapy.

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