Mevion S250i Proton Therapy System
No abstract available (Source: Biomedical Safety and Standards)
Source: Biomedical Safety and Standards - February 25, 2019 Category: Medical Devices Tags: RECALLS & FIELD CORRECTIONS—CLASS II Source Type: research

Proteus 235 Proton Therapy System
No abstract available (Source: Biomedical Safety and Standards)
Source: Biomedical Safety and Standards - February 25, 2019 Category: Medical Devices Tags: RECALLS & FIELD CORRECTIONS—CLASS II Source Type: research

Impact of TPS calculation algorithms on dose delivered to the patient in proton therapy treatments.
Conclusion: Different TPS dose calculation approaches mainly affected dose delivered in H&N proton treatments, while minor deviations were found for pelvic tumors. RS-MC proved to be the most accurate TPS dose calculation algorithm when compared to an independent MC simulation code. PMID: 30802887 [PubMed - as supplied by publisher] (Source: Physics in Medicine and Biology)
Source: Physics in Medicine and Biology - February 25, 2019 Category: Physics Authors: Molinelli S, Russo S, Magro G, Maestri D, Mairani A, Mastella E, Mirandola A, Vai A, Vischioni B, Valvo F, Ciocca M Tags: Phys Med Biol Source Type: research

Clinical Outcomes of Patients with Recurrent Lung Cancer Reirradiated with Proton Therapy on the Proton Collaborative Group and University of Florida Proton Therapy Institute Prospective Registry Studies
ConclusionThis is the largest series to date of PBT reirradiation for recurrent lung cancer, showing that reirradiation with PBT is well tolerated with acceptable toxicity and encouraging efficacy. ECOG performance status was associated with OS and PFS. (Source: Practical Radiation Oncology)
Source: Practical Radiation Oncology - February 23, 2019 Category: Cancer & Oncology Source Type: research

Proton therapy for thymic malignancies: multi-institutional patterns-of-care and early clinical outcomes from the proton collaborative group and the university of Florida prospective registries.
CONCLUSION: Adjuvant and definitive PT are being used in the treatment of TMs. Early results of the largest such cohort reported to date demonstrates an acceptable rate of recurrence with a favorable toxicity profile. Longer follow-up and a larger patient cohort are needed to confirm these findings. PMID: 30784340 [PubMed - as supplied by publisher] (Source: Acta Oncologica)
Source: Acta Oncologica - February 20, 2019 Category: Cancer & Oncology Authors: Mercado CE, Hartsell WF, Simone CB, Tsai HK, Vargas CE, Zhu HJ, Henderson RH, Zeng J, Larson GL, Hoppe BS Tags: Acta Oncol Source Type: research

The dosimetric effect of residual breath-hold motion in pencil beam scanned proton therapy – An experimental study
Motion management in pencil beam scanned (PBS) proton therapy of mobile lung tumours is a prerequisite for accurate dose delivery [1]. Due to uncertainties caused by the motion (e.g. [2]), only a few PBS proton therapy centres offer lung cancer treatments [3], despite PBS potentially being superior to other techniques [4]. It should be mentioned however, that many lung cancer patients have been treated by ion beam therapy with good results (e.g. [5]). Similarly to conventional treatments with photons, for proton treatments, motion is typically accounted for in the planning step by increasing the margins around the target. ...
Source: Radiotherapy and Oncology - February 14, 2019 Category: Radiology Authors: Jenny Gorgisyan, Antony J. Lomax, Per Munck af Rosenschold, Gitte F. Persson, Miriam Krieger, Emma Colvill, Jonas Scherman, Francis Gagnon-Moisan, Martina Egloff, Giovanni Fattori, Svend Aage Engelholm, Damien C. Weber, Rosalind Perrin Tags: Original Article Source Type: research

Impact of aeration change and beam arrangement on the robustness of proton plans.
This study determines the impact of change in aeration in sinonasal cavities on the robustness of passive-scattering proton therapy plans in patients with sinonasal and nasopharyngeal malignancies. Fourteen patients, each with one planning CT and one CT acquired during radiotherapy were studied. Repeat and planning CTs were rigidly aligned and contours were transferred using deformable registration. The amount of air, tumor, and fluid within the cavity containing the tumor were measured on both CTs. The original plans were recalculated on the repeat CT. Dosimetric changes were measured for the targets and critical structur...
Source: Journal of Applied Clinical Medical Physics - February 12, 2019 Category: Physics Authors: Shusharina N, Fullerton B, Adams JA, Sharp GC, Chan AW Tags: J Appl Clin Med Phys Source Type: research

Three discipline collaborative radiation therapy (3DCRT) special debate: The United States should build additional proton therapy facilities.
PMID: 30735613 [PubMed - as supplied by publisher] (Source: Journal of Applied Clinical Medical Physics)
Source: Journal of Applied Clinical Medical Physics - February 8, 2019 Category: Physics Authors: Braunstein S, Wang L, Newhauser W, Tenenholz T, Rong Y, van der Kogel A, Dominello M, Joiner MC, Burmeister J Tags: J Appl Clin Med Phys Source Type: research

Outcomes after Proton Therapy for Treatment of Pediatric High-Risk Neuroblastoma
We present the largest ever population of patients with neuroblastoma treated with proton therapy, demonstrating minimal toxicity and 97% local disease free survival. This treatment is safe and allows minimization of dose to normal tissues in young patients with neuroblastoma, who require intensive multimodality therapy. (Source: International Journal of Radiation Oncology * Biology * Physics)
Source: International Journal of Radiation Oncology * Biology * Physics - February 7, 2019 Category: Radiology Authors: Christine E. Hill-Kayser, Zelig Tochner, Yimei Li, Goldie Kurtz, Robert A. Lustig, Paul James, Naomi Balamuth, Richard Womer, Peter Mattei, Stephen Grupp, Yael P. Mosse, John M. Maris, Rochelle Bagatell Tags: Clinical Investigation Source Type: research

4DMRI-based investigation on the interplay effect for pencil beam scanning proton therapy of pancreatic cancer patients
Time-resolved volumetric magnetic resonance imaging (4DMRI) offers the potential to analyze 3D motion with high soft-tissue contrast without additional imaging dose. We use 4DMRI to investigate the interplay e... (Source: Radiation Oncology)
Source: Radiation Oncology - February 7, 2019 Category: Cancer & Oncology Authors: Kai Dolde, Ye Zhang, Naved Chaudhri, Christian D ávid, Marc Kachelrieß, Antony John Lomax, Patrick Naumann, Nami Saito, Damien Charles Weber and Asja Pfaffenberger Tags: Research Source Type: research

Second malignant neoplasm risk after craniospinal irradiation in X-ray-based techniques compared to proton therapy
AbstractCranio-spinal irradiation (CSI) is widely used for treating medulloblastoma cases in children. Radiation-induced second malignancy is of grave concern; especially in children due to their long-life expectancy and higher radiosensitivity of tissues at young age. Several techniques can be employed for CSI including 3DCRT, IMRT, VMAT and tomotherapy. However, these techniques are associated with higher risk of second malignancy due to the physical characteristics of photon irradiation which deliver moderately higher doses to normal tissues. On the other hand, proton beam therapy delivers substantially lesser dose to n...
Source: Australasian Physical and Engineering Sciences in Medicine - February 6, 2019 Category: Biomedical Engineering Source Type: research

Effect of setup and inter-fraction anatomical changes on the accumulated dose in CT-guided breath-hold intensity modulated proton therapy of liver malignancies
Liver cancer is one of the most common causes of cancer-related deaths [1,2]. Radiotherapy for liver cancer is difficult because of the low tolerance of the liver to radiation, sparing of adjacent normal structures, respiratory motion, and challenges in localizing the intrahepatic target during radiotherapy [3 –6]. Compared with radiotherapy with photons, e.g., intensity-modulated photon therapy (IMRT), proton therapy is characterized by a sharp dose fall-off around the target volume. Therefore, proton therapy can deliver a higher dose to liver tumor while preserving much more normal liver tissue than I MRT [1]. (Sou...
Source: Radiotherapy and Oncology - February 6, 2019 Category: Radiology Authors: Zhiyong Yang, Yu Chang, Kristy K. Brock, Guillaume Cazoulat, Eugene J. Koay, Albert C. Koong, Joseph M. Herman, Peter C. Park, Falk Poenisch, Qin Li, Kunyu Yang, Gang Wu, Brian Anderson, Andrea N. Ohrt, Yupeng Li, X. Ronald Zhu, Xiaodong Zhang, Heng Li Tags: Original Article Source Type: research

Chemotherapy to Spare Cognition
In this 13-month-old girl with anaplastic ependymoma, biopsy of the suspicious mass is strongly recommended because treatment varies significantly if the disease has metastasized.1 If this mass is benign, we recommend radiation to the primary tumor bed with 5  mm clinical target volume and 3 mm planning target volume margins using proton therapy to a total dose of 54 Gy (relative biological effectiveness) (Fig. 1). If the spinal disease is biopsy-proven metastatic ependymoma, there are several options, though none ideal. (Source: International Journal of Radiation Oncology * Biology * Physics)
Source: International Journal of Radiation Oncology * Biology * Physics - February 1, 2019 Category: Radiology Authors: Benjamin T. Cooper, Julie A. Bradley Tags: Gray Zone Source Type: research

Regularised patient-specific stopping power calibration for proton therapy planning based on proton radiographic images.
Abstract Proton transmission imaging has been proposed and investigated as imaging modality complementary to X-ray based techniques in proton beam therapy. In particular, it addresses the issue of range uncertainties due to the conversion of an X-ray patient computed tomography (CT) image expressed in Hounsfield Units (HU) to relative stopping power (RSP) needed as input to the treatment planning system. One approach to exploit a single proton radiographic projection is to perform a patient-specific calibration of the CT to RSP conversion curve by optimising the match between a measured and a numerically integrate...
Source: Physics in Medicine and Biology - February 1, 2019 Category: Physics Authors: Krah N, Patera V, Rit S, Schiavi A, Rinaldi I Tags: Phys Med Biol Source Type: research

A new facility for proton radiobiology at the Trento proton therapy centre: Design and implementation
In parallel to the growth in number of proton therapy centres [1], an increasing interest is registered concerning experimental facilities where proton radiobiology studies can be performed. This is confirmed by the recent survey published by the European Particle Therapy network radiobiology group [2]. The motivation lies in the extensive research activity on going in the field. While the physical advantages offered by proton therapy are nowadays established (i.e. improved selectivity in the release of dose due to the Bragg peak profile, which reflects into the possibility to spare healthy tissues compared to photon radia...
Source: Physica Medica: European Journal of Medical Physics - February 1, 2019 Category: General Medicine Authors: Francesco Tommasino, Marta Rovituso, Eleonora Bortoli, Chiara La Tessa, Giada Petringa, Stefano Lorentini, Enrico Verroi, Yuri Simeonov, Ulrich Weber, Pablo Cirrone, Marco Schwarz, Marco Durante, Emanuele Scifoni Tags: Original paper Source Type: research

Radiobiological quantities in proton-therapy: Estimation and validation using Geant4-based Monte Carlo simulations
An increasing number of radiotherapy facilities make, use of accelerated charged beams to treat tumours. Since 1954, approximately 174,000 patients were treated with ions: the vast majority with protons, but heavier particles such as 12C ions have also been used [1]. The main reason for this rapid growth lies in the better physical selectivity offered by protons compared to electrons and gamma rays. In addition to the advantages offered by the peculiar depth-dose profile, protons also show an enhanced biological effectiveness in cell killing [2] towards the end of the clinical SOBP (Spread Out Bragg Peak). (Source: Physica...
Source: Physica Medica: European Journal of Medical Physics - February 1, 2019 Category: General Medicine Authors: G. Petringa, F. Romano, L. Manti, L. Pandola, A. Attili, F. Cammarata, G. Cuttone, G. Forte, L. Manganaro, J. Pipek, P. Pisciotta, G. Russo, G.A.P. Cirrone Tags: Original paper Source Type: research

Clinical intensity-modulated proton therapy for Hodgkin lymphoma: which patients benefit the most?
ConclusionsPBS gives good target coverage and local control whilst providing reductions in radiation dose to OAR for individuals receiving RT for HL compared to advanced photon RT. Our findings highlight certain groups of patients who would be expected to gain more dosimetric benefit from PBS. These findings facilitate the selection of patients who should be considered a priority for PT. (Source: Practical Radiation Oncology)
Source: Practical Radiation Oncology - January 30, 2019 Category: Cancer & Oncology Source Type: research

Selection of lymph node target volumes for definitive head and neck radiation therapy: a 2019 Update
Intensity Modulated Radiation Therapy (IMRT), Volumetric Modulated Arctherapy (VMAT) or other highly conformal techniques (e.g. proton therapy) are techniques that allow precise targeting of the volumes to be irradiated while protecting healthy tissue. In 2018, it is the standard method of irradiation of head and neck cancers [1 –5]. Because of their precision, these techniques require that each target volume be strictly and rigorously defined. The delineation and selection of these volumes is complex and requires a solid learning curve. (Source: Radiotherapy and Oncology)
Source: Radiotherapy and Oncology - January 30, 2019 Category: Radiology Authors: Julian Biau, Michel Lapeyre, Idriss Troussier, Wilfried Budach, Jordi Giralt, Cai Grau, Joanna Kazmierska, Johannes A. Langendijk, Mahmut Ozsahin, Brian O'Sullivan, Jean Bourhis, Vincent Gr égoire Tags: Guidelines Source Type: research

Tumor control in RG2 glioma-bearing rats: a comparison between proton minibeam therapy and standard proton therapy
This study is the first in vivo evaluation of the effectiveness of proton minibeam radiation therapy for the treatment of high-grade gliomas. Superior tumour control was obtained in the pMBRT group in comparison with the standard proton therapy group. Tumour eradication was observed in the majority (67%) of the animals treated with pMBRT with reduced side effects. The tumour eradication achieved despite the lack of homogenous target coverage contradicts the classical paradigm of RT. (Source: International Journal of Radiation Oncology * Biology * Physics)
Source: International Journal of Radiation Oncology * Biology * Physics - January 28, 2019 Category: Radiology Authors: Yolanda Prezado, Gregory Jouvion, Consuelo Guardiola, Wilfredo Gonzalez, Marjorie Juchaux, Judith Bergs, Catherine Nauraye, Dalila Labiod, Ludovic De Marzi, Frederic Pouzoulet, Annalisa Patriarca, Remi Dendale Source Type: research

Preliminary result of definitive radiotherapy in patients with non-small cell lung cancer who have underlying idiopathic pulmonary fibrosis: comparison between X-ray and proton therapy
Idiopathic pulmonary fibrosis (IPF) is associated with fatal complications after radiotherapy (RT) for lung cancer patients; however, the role of proton therapy to reduce the incidence of life-threatening comp... (Source: Radiation Oncology)
Source: Radiation Oncology - January 28, 2019 Category: Cancer & Oncology Authors: Hakyoung Kim, Hongryull Pyo, Jae Myoung Noh, Woojin Lee, Byoungsuk Park, Hye Yun Park and Hongseok Yoo Tags: Research Source Type: research

Are further studies needed to justify the use of proton therapy for paediatric cancers of the central nervous system? A review of current evidence
Although progress has been achieved in the treatment of CNS tumours, significant morbidity and mortality are still associated with childhood brain cancers. Current therapeutic strategies include a combination of surgery, chemotherapy and radiotherapy. While all treatment methods impose a certain risk, traditional photon-based treatments carry a high risk of adverse events, especially in very young patients. The more optimal physical and radiobiological properties of protons as compared to photons, have justified their implementation in radiotherapy, with several studies reporting promising results in otherwise difficult-to...
Source: Radiotherapy and Oncology - January 28, 2019 Category: Radiology Authors: Myxuan Huynh, Loredana Gabriela Marcu, Eileen Giles, Michala Short, Donna Matthews, Eva Bezak Tags: Review Article Source Type: research

Long-term Outcomes of Globe-Preserving Surgery Followed With Proton Beam Radiation for Adenoid Cystic Carcinoma of Lacrimal Gland
Wolkow and associates describe their retrospective experience in 18 patients with lacrimal gland adenoid cystic carcinoma (LGACC) who had globe-preserving surgery with high-dose mixed radiation beams of protons and photons.1 The title is slightly misleading, since only 1 patient received proton therapy alone and the remainder received a combination of protons and x-ray therapy. The authors used passive scattering proton beams with x-ray therapy. The “modern” technique of proton therapy uses active scanning proton beam delivery and intensity-modulated proton therapy (IMPT) that eliminates the need for photon the...
Source: American Journal of Ophthalmology - January 24, 2019 Category: Opthalmology Authors: Bita Esmaeli, Steven J. Frank Tags: Correspondence Source Type: research

Antibody-functionalized gold nanoparticles as tumor targeting radiosensitizers for proton therapy
Nanomedicine, Ahead of Print. (Source: Future Medicine: Nanomedicine)
Source: Future Medicine: Nanomedicine - January 24, 2019 Category: Nanotechnology Authors: Sha Li Sandra Bouchy Sebastien Penninckx Riccardo Marega Ornella Fichera Bernard Gallez Olivier Feron Philippe Martinive Anne-Catherine Heuskin Carine Michiels St éphane Lucas Source Type: research

Antibody-functionalized gold nanoparticles as tumor targeting radiosensitizers for proton therapy
Nanomedicine, Ahead of Print. (Source: Nanomedicine)
Source: Nanomedicine - January 24, 2019 Category: Nanotechnology Authors: Sha Li Sandra Bouchy Sebastien Penninckx Riccardo Marega Ornella Fichera Bernard Gallez Olivier Feron Philippe Martinive Anne-Catherine Heuskin Carine Michiels St éphane Lucas Source Type: research

Antibody-functionalized gold nanoparticles as tumor-targeting radiosensitizers for proton therapy
Nanomedicine,Volume 14, Issue 3, Page 317-333, February 2019. (Source: Future Medicine: Nanomedicine)
Source: Future Medicine: Nanomedicine - January 24, 2019 Category: Nanotechnology Authors: Sha Li Sandra Bouchy Sebastien Penninckx Riccardo Marega Ornella Fichera Bernard Gallez Olivier Feron Philippe Martinive Anne-Catherine Heuskin Carine Michiels St éphane Lucas Source Type: research

Antibody-functionalized gold nanoparticles as tumor-targeting radiosensitizers for proton therapy
Nanomedicine,Volume 14, Issue 3, Page 317-333, February 2019. (Source: Nanomedicine)
Source: Nanomedicine - January 24, 2019 Category: Nanotechnology Authors: Sha Li Sandra Bouchy Sebastien Penninckx Riccardo Marega Ornella Fichera Bernard Gallez Olivier Feron Philippe Martinive Anne-Catherine Heuskin Carine Michiels St éphane Lucas Source Type: research

Long-term Outcomes of Globe-Preserving Surgery with Proton Beam Radiation for Adenoid Cystic Carcinoma of the Lacrimal Gland
Wolkow and associates describe their retrospective experience in 18 patients with lacrimal gland adenoid cystic carcinoma (LGACC) who had globe-preserving surgery with high-dose mixed radiation beams of protons and photons.1 The title is slightly misleading, since only 1 patient received proton therapy alone and the remainder received a combination of protons and x-ray therapy. The authors used passive scattering proton beams with x-ray therapy. The “modern” technique of proton therapy uses active scanning proton beam delivery and intensity-modulated proton therapy (IMPT) that eliminates the need for photon the...
Source: American Journal of Ophthalmology - January 24, 2019 Category: Opthalmology Authors: Bita Esmaeli, Steven J. Frank Tags: Correspondence Source Type: research

Mechanically-assisted non-invasive ventilation: A step forward to modulate and to improve the reproducibility of breathing-related motion in radiation therapy
Radiotherapy of mobile tumours entails many challenges due to the uncertainties of the target position caused by breathing. Indeed, the breathing amplitude and frequency may deeply and unexpectedly vary from cycle to cycle, as they are subject to deep conscious and unconscious variations. These changes can occur either within a same treatment fraction (intra-fraction variation), or from one day to another (inter-fraction variation). In proton-therapy, the uncertainties in target position are even worsened by the proton range variations within the crossed tissues and the interplay effect (the interferences between the targe...
Source: Radiotherapy and Oncology - January 24, 2019 Category: Radiology Authors: Genevi ève Van Ooteghem, Damien Dasnoy-Sumell, Maarten Lambrecht, Grégory Reychler, Giuseppe Liistro, Edmond Sterpin, Xavier Geets Tags: Orignal Article Source Type: research

Outcomes Following Proton Therapy for Pediatric Low-Grade Glioma
Our cohort of 174 pediatric patients with low-grade glioma demonstrate progression-free survival and overall survival rates of 84% and 92%, respectively, following proton therapy. These survival rates are similar to contemporary photon cohorts. Data from this prospective study inform radiation technique and overall patient management for the most common pediatric brain tumor. (Source: International Journal of Radiation Oncology * Biology * Physics)
Source: International Journal of Radiation Oncology * Biology * Physics - January 23, 2019 Category: Radiology Authors: Daniel J. Indelicato, Ronny L. Rotondo, Haruka Uezono, Eric S. Sandler, Philipp R. Aldana, Nathan J. Ranalli, Alexandra D. Beier, Christopher G. Morris, Julie A. Bradley Tags: Clinical Investigation Source Type: research

A linear relationship for the LET-dependence of Gafchromic EBT3 film in spot-scanning proton therapy.
Abstract Radiochromic film is a valuable dosimetric tool, primarily due to its sub-millimeter spatial resolution. For accurate proton dosimetry, the dependence of film response on linear energy transfer must be characterized and calibrated. In this work, we characterized film under-response, or "quenching," as a function of dose-weighted linear energy transfer (LETd) in several proton fields and established a simple, linear relationship with LETd. We performed measurements as a function of depth in a PMMA phantom irradiated by a spot-scanning proton beam. The fields had energies of 71.3 MeV, ...
Source: Physics in Medicine and Biology - January 23, 2019 Category: Physics Authors: Anderson SE, Grams MP, Wan Chan Tseung H, Furutani KM, Beltran CJ Tags: Phys Med Biol Source Type: research

Dosimetric verification of IMPT using a commercial heterogeneous phantom.
Abstract The purpose of this study was to propose a verification method and results of intensity-modulated proton therapy (IMPT), using a commercially available heterogeneous phantom. We used a simple simulated head and neck and prostate phantom. An ionization chamber and radiochromic film were used for measurements of absolute dose and relative dose distribution. The measured doses were compared with calculated doses using a treatment planning system. We defined the uncertainty of the measurement point of the ionization chamber due to the effective point of the chamber and mechanical setup error as 2 mm and ...
Source: Journal of Applied Clinical Medical Physics - January 23, 2019 Category: Physics Authors: Yasui K, Toshito T, Omachi C, Hayashi K, Kinou H, Katsurada M, Hayashi N, Ogino H Tags: J Appl Clin Med Phys Source Type: research

Impact of unfavorable factors on outcomes among inoperable stage II-IV Nonsmall cell lung cancer patients treated with proton therapy.
Abstract PURPOSE: To investigate the impact of unfavorable risk factors among patients with locally advanced nonsmall cell lung cancer (LA-NSCLC) treated with proton therapy (PT). MATERIAL AND METHODS: From May 2008 through July 2015, 90 consecutive patients with unresectable stage II-IV (oligometastatic) NSCLC were treated with PT. Unfavorable factors including age ≥80 years, stage IV, weight loss>10% in 3 months, performance status (PS) ≥2, FEV1 
Source: Acta Oncologica - January 18, 2019 Category: Cancer & Oncology Authors: Zhu HJ, Nichols RC, Henderson RH, Morris CG, Flampouri S, Pham DC, Klassen CL, Seeram V, Cury JD, Jones L, McGee L, Hoppe BS Tags: Acta Oncol Source Type: research

Implementation of proton therapy treatments with pencil beam scanning of targets with limited intrafraction motion
Pencil beam scanning (PBS) is the most common delivery technique in proton therapy nowadays because of its high potential to reach good dose homogeneity to the target and organs at risk (OAR) sparing. It is possible to modulate each beam in terms of position, intensity and energy to reach the best plan quality. In case of static lesions, the quality of the dose distribution can be more easily ensured as long as position and range uncertainty are taken into account. For moving targets the intra-fraction anatomy changes can have a great impact on the dose distribution [1]. (Source: Physica Medica: European Journal of Medical Physics)
Source: Physica Medica: European Journal of Medical Physics - January 17, 2019 Category: General Medicine Authors: Francesco Fracchiolla, Francesco Dionisi, Irene Giacomelli, Sebastian Hild, Pier Giorgio Esposito, Stefano Lorentini, Erik Engwall, Maurizio Amichetti, Marco Schwarz Tags: Original paper Source Type: research

A novel methodology to assess linear energy transfer and relative biological effectiveness in proton therapy using pairs of differently doped thermoluminescent detectors.
Abstract A new methodology for assessing linear energy transfer (LET) and relative biological effectiveness (RBE) in proton therapy beams using thermoluminescent detectors is presented. The method is based on the different LET response of two different lithium fluoride thermoluminescent detectors (LiF:Mg,Ti and LiF:Mg,Cu,P) for measuring charged particles. The relative efficiency of the two detector types was predicted using the recently developed Microdosimetric d(z) Model in combination with the Monte Carlo code PHITS. Afterwards, the calculated ratio of the expected response of the two detector types was correl...
Source: Physics in Medicine and Biology - January 16, 2019 Category: Physics Authors: Parisi A, Chiriotti S, De Saint-Hubert M, Van Hoey O, Vandevoorde C, Beukes P, de Kock EA, Symons J, Nieto-Camero J, Slabbert J, Megret P, Debrot E, Bolst D, Rozenfeld AB, Vanhavere F Tags: Phys Med Biol Source Type: research

Is Proton Therapy a “Pro” for Breast Cancer? A Comparison of Proton vs. Non-proton Radiotherapy Using the National Cancer Database
Mudit Chowdhary, Anna Lee, Sarah Gao, Dian Wang, Parul N. Barry, Roberto Diaz, Neeti R. Bagadiya, Henry S. Park, James B. Yu, Lynn D. Wilson, Meena S. Moran, Susan A. Higgins, Christin A. Knowlton, Kirtesh R. Patel (Source: Frontiers in Oncology)
Source: Frontiers in Oncology - January 14, 2019 Category: Cancer & Oncology Source Type: research

Optimal combined proton-photon therapy schemes based on the standard BED model.
te; Z Abstract This paper investigates the potential of combined proton-photon therapy treatments in radiation oncology, with a special emphasis on fractionation. Several combined modality models, with and without fractionation, are discussed, and conditions under which combined modality treatments are of added value are demonstrated analytically and numerically. The combined modality optimal fractionation problem with multiple normal tissues is formulated based on the Biologically Effective Dose (BED) model and tested on real patient data. Results indicate that for several patients a combined modality treatment g...
Source: Physics in Medicine and Biology - January 14, 2019 Category: Physics Authors: Ten Eikelder SCM, den Hertog D, Bortfeld TR, Perkó Z Tags: Phys Med Biol Source Type: research

Evaluation of the ray-casting analytical algorithm for pencil beam scanning proton therapy.
In conclusion, we would recommend using the ray-casting algorithm for fast dose optimization and subsequently combine it with one Monte Carlo calculation to scale the absolute dose and assure the quality of the treatment plan. PMID: 30641496 [PubMed - as supplied by publisher] (Source: Physics in Medicine and Biology)
Source: Physics in Medicine and Biology - January 14, 2019 Category: Physics Authors: Winterhalter C, Zepter S, Shim S, Meier G, Bolsi A, Fredh A, Hrbacek J, Oxley D, Zhang Y, Weber DC, Lomax AJ, Safai S Tags: Phys Med Biol Source Type: research

Improving dosimetric outcome for hippocampus and cochlea sparing whole brain radiotherapy using spot-scanning proton arc therapy.
Abstract This feasibility study shows that Spot-scanning Proton Arc therapy (SPArc) is able to significantly reduce the dose to the hippocampus and cochlea compared to both Volumetric Modulated Arc Photon Therapy (VMAT) and the robust optimized Intensity Modulated Proton Therapy (ro-IMPT) plans in whole brain radiotherapy. Furthermore, SPArc not only improves plan robustness but could potentially deliver a treatment as efficient as ro-IMPT when proton system's energy layer switch time is less than 1 s. PMID: 30632851 [PubMed - as supplied by publisher] (Source: Acta Oncologica)
Source: Acta Oncologica - January 11, 2019 Category: Cancer & Oncology Authors: Ding X, Zhou J, Li X, Blas K, Liu G, Wang Y, Qin A, Chinnaiyan P, Yan D, Stevens C, Grills I, Kabolizadeh P Tags: Acta Oncol Source Type: research

Long-term results of a phase II study of hypofractionated proton therapy for prostate cancer: moderate versus extreme hypofractionation
This study was an exploratory analysis to investigate the secondary end... (Source: Radiation Oncology)
Source: Radiation Oncology - January 10, 2019 Category: Cancer & Oncology Authors: Boram Ha, Kwan Ho Cho, Kang Hyun Lee, Jae Young Joung, Yeon-Joo Kim, Sung Uk Lee, Hyunjung Kim, Yang-Gun Suh, Sung Ho Moon, Young Kyung Lim, Jong Hwi Jeong, Haksoo Kim, Weon Seo Park and Sun Ho Kim Tags: Research Source Type: research

Proton beam therapy in pediatric oncology
Purpose of review The advent of proton beam therapy (PBT) has initiated a paradigm shift in the field of pediatric radiation oncology, with increasing promise to alleviate both short-term and long-term toxicities. Given the dramatic rise in proton therapy centers in the United States, a discussion of the quality of evidence supporting its use in pediatric cancers is warranted. Recent findings Proton radiotherapy appears to decrease the incidence and severity of late effects with the strongest evidence in pediatric brain tumor cohorts that shows benefits in neurocognitive, hearing, and endocrine outcomes. However, emer...
Source: Current Opinion in Pediatrics - January 8, 2019 Category: Pediatrics Tags: HEMATOLOGY AND ONCOLOGY: Edited by Susan M. Blaney Source Type: research

A model-based approach to predict short-term toxicity benefits with proton therapy for oropharyngeal cancer
The aim of this study was to generate normal tissue complication probability (NTCP) models in patients treated with either proton beam therapy (PBT) or intensity-modulated radiotherapy (IMRT) for oropharynx cancer, and to use a model-based approach to investigate the added value of PBT in preventing treatment complications. (Source: International Journal of Radiation Oncology * Biology * Physics)
Source: International Journal of Radiation Oncology * Biology * Physics - January 6, 2019 Category: Radiology Authors: Jean-Claude M. Rwigema, Johannes A. Langendijk, Hans Paul van der Laan, John N. Lukens, Samuel D. Swisher-McClure, Alexander Lin Tags: Clinical Investigation Source Type: research

TOPAS-nBio: An Extension to the TOPAS Simulation Toolkit for Cellular and Sub-cellular Radiobiology.
In conclusion, the TOPAS-nBio extension to the TOPAS MC application offers access to accurate and detailed multiscale simulations, from a macroscopic description of the radiation field to microscopic description of biological outcome for selected cells. TOPAS-nBio offers detailed physics and chemistry simulations of radiobiological experiments on cells simulating the initially induced damage and links to models of DNA repair kinetics. PMID: 30609382 [PubMed - as supplied by publisher] (Source: Radiation Research)
Source: Radiation Research - January 4, 2019 Category: Physics Authors: Schuemann J, McNamara AL, Ramos-Méndez J, Perl J, Held KD, Paganetti H, Incerti S, Faddegon B Tags: Radiat Res Source Type: research

Cancers, Vol. 11, Pages 35: Potential for Improvements in Robustness and Optimality of Intensity-Modulated Proton Therapy for Lung Cancer with 4-Dimensional Robust Optimization
Conclusion: The incorporation of respiratory motion, along with setup and range uncertainties, into robust optimization, has the potential to improve the resilience of target and normal tissue dose distributions in IMPT plans in the face of the uncertainties considered. Moreover, it improves the optimality of plans compared to PTV-based optimization as well as 3DRO. (Source: Cancers)
Source: Cancers - January 1, 2019 Category: Cancer & Oncology Authors: Shuaiping Ge Xiaochun Wang Zhongxing Liao Lifei Zhang Narayan Sahoo Jinzhong Yang Fada Guan Radhe Mohan Tags: Article Source Type: research

Evaluation of deformable image registration accuracy for CT images of the thorax region
External beam radiation therapy may increase survival for patients with lung tumors [1 –3]. However, radiation therapy in the thorax region is associated with uncertainties due to respiratory motions that could alter the effect of the treatment from what was planned. This is especially important for modulated treatment techniques such as volumetric modulated arc therapy (VMAT) or in tensity modulated proton therapy (IMPT) where the absorbed dose to the target volume is successively built up from different small beam segments covering different parts of the total target volume. (Source: Physica Medica: European Journa...
Source: Physica Medica: European Journal of Medical Physics - January 1, 2019 Category: General Medicine Authors: Sebastian Sarudis, Anna Karlsson, Dan Bibac, Jan Nyman, Anna B äck Tags: Original paper Source Type: research

A pre-absorber optimization technique for pencil beam scanning proton therapy treatments
In pencil beam scanning proton therapy treatments is possible to treat almost all tumors without using any passive object on the beamline. The only parameter that forces to use a passive beam modifier is the minimum energy. Usually the minimum energy is either 70 or 100  MeV [1], corresponding to 4.1 cm or 7.5 cm of water equivalent thickness, respectively [1]. This means that, for minimum energies available of 70 MeV, tumors located at a water equivalent depth shallower than 4 cm cannot be treated if a pre-absorber is not used. (Source: Physica Medica: European Journal of Medical Physics)
Source: Physica Medica: European Journal of Medical Physics - January 1, 2019 Category: General Medicine Authors: Francesco Fracchiolla, Francesco Fellin, Marta Innocenzi, Mirko Lipparini, Stefano Lorentini, Lamberto Widesott, Paolo Farace, Marco Schwarz Tags: Original paper Source Type: research

Impact of spot size variations on dose in scanned proton beam therapy
In Intensity Modulated Proton Therapy (IMPT), dose is delivered to the patient by combining the dose from numerous small proton beams (spots) with a certain lateral size, energy, position, and number of protons. To ensure that the planned and delivered dose correspond, the spot characteristics must be stable. The lateral size of the spots is a parameter for which it is challenging to guarantee perfect stability over time [1 –5]. Beam size changes could occur as a result of variations in the proton accelerator (e.g. (Source: Physica Medica: European Journal of Medical Physics)
Source: Physica Medica: European Journal of Medical Physics - January 1, 2019 Category: General Medicine Authors: A.C. Kraan, N. Depauw, B. Clasie, T. Madden, H.M. Kooy Tags: Original paper Source Type: research

Including anatomical variations in robust optimization for head and neck proton therapy can reduce the need of adaptation
Intensity-modulated proton therapy (IMPT) has shown to be promising for the treatment of head and neck squamous cell carcinoma (HNSCC) patients, due to its high-dose conformity and reduced dose to the normal tissue in comparison with photon-based intensity-modulated radiation therapy (IMRT) [1 –4]. However, due to its physical characteristics, protons are more sensitive to deviations from the nominal situation, for instance variations in the patient setup, uncertainties in the proton range and treatment-induced changes in the patient anatomy during the treatment course, which can result in degradation of the delivere...
Source: Radiotherapy and Oncology - December 31, 2018 Category: Radiology Authors: Macarena Cubillos-Mes ías, Esther G.C. Troost, Fabian Lohaus, Linda Agolli, Maximilian Rehm, Christian Richter, Kristin Stützer Tags: Original Article Source Type: research

A quality assurance for respiratory gated proton irradiation with range modulation wheel.
Abstract The purpose of this study was to provide periodic quality assurance (QA) methods for respiratory-gated proton beam with a range modulation wheel (RMW) and to clarify the characteristics and long-term stability of the respiratory-gated proton beam. A two-dimensional detector array and a solid water phantom were used to measure absolute dose, spread-out Bragg peak (SOBP) width and proton range for monthly QA. SOBP width and proton range were measured using an oblique incidence beam to the lateral side of a solid water phantom and compared between with and without a gating proton beam. To measure the delay t...
Source: Journal of Applied Clinical Medical Physics - December 30, 2018 Category: Physics Authors: Yasui K, Shimomura A, Toshito T, Tanaka K, Ueki K, Muramatsu R, Katsurada M, Hayashi N, Ogino H Tags: J Appl Clin Med Phys Source Type: research

Can CT imaging improve targeting accuracy in clip-based proton therapy of ocular melanoma?
Conclusion: Adding CT imaging to the simulation process is beneficial in select cases where discrepancies between the eye model and ophthalmology measurements occur or where a critical structure is located close to the target and improved localization accuracy is wanted. For the majority of patients, addition of CT imaging does not result in quantifiable changes in dosimetry. Nevertheless, CT imaging is a valuable tool in the quality control of the modeling and treatment-planning process of clip-based eye treatments. PMID: 30566923 [PubMed - as supplied by publisher] (Source: Physics in Medicine and Biology)
Source: Physics in Medicine and Biology - December 19, 2018 Category: Physics Authors: Slopsema RL, Mamalui M, Bolling J, Flampouri S, Yeung D, Li Z, Rutenberg MS, Dagan R Tags: Phys Med Biol Source Type: research

A single detector energy-resolved proton radiography system: a proof of principle study by Monte Carlo simulations.
In this study, we followed a newly proposed proton beam radiography technique based on energy resolved dose functions (ERDF) to construct a Monte Carlo model for a single detector energy-resolved proton radiography system (SDPRS). This SDPRS model was constructed in the Monte Carlo software package TOPAS (TOol for PArticle Simulation) and it includes the Mevion HYPERSCANTM pencil beam scanning treatment head and a 2D dose detector positioned downstream as the imager. A calibration phantom containing a number of tissue equivalent materials was simulated to evaluate the accuracy in WEPL measurement by SDPRS. The mean deviati...
Source: Physics in Medicine and Biology - December 18, 2018 Category: Physics Authors: Huo W, Zwart T, Cooley JE, Huang K, Finley C, Jee KW, Sharp GC, Rosenthal S, Xu XG, Lu HM Tags: Phys Med Biol Source Type: research