Proton therapy for the treatment of pediatric head and neck cancers: a review
Pediatric malignancies are the leading cause of disease-related death in children and the second overall cause of death after accidents. In 2014 there were 15,780 new pediatric cancer cases and nearly 2,000 deaths [1]. Fortunately, survival rates among children diagnosed with cancer are improving, with 5 year survival rates approaching 80% [2,3]. While combining surgery, chemotherapy and/or radiation therapy are effective curative methods, children are especially vulnerable to late side effects that might not be applicable to adults receiving similar treatment. (Source: International Journal of Pediatric Otorhinolaryngology)
Source: International Journal of Pediatric Otorhinolaryngology - November 3, 2015 Category: ENT & OMF Authors: Rafi Kabarriti, Daniel Mark, Jana Fox, Shalom Kalnicki, Madhur Garg Tags: Review Article Source Type: research

Evaluation of the local dose enhancement in the combination of proton therapy and nanoparticles.
CONCLUSIONS: The authors' results indicate that physical effects play a minor role in the amplification of damage, as a very low dose enhancement or increase of dissociative electron attachment processes is observed when the authors get closer to more realistic simulations. Thus, other effects, such as biological or chemical processes, may be mainly responsible for the enhanced radiosensibilization observed in biological studies. However, more biological studies are needed to verify this hypothesis. PMID: 26520760 [PubMed - in process] (Source: Physica Medica)
Source: Physica Medica - November 1, 2015 Category: Physics Authors: Martínez-Rovira I, Prezado Y Tags: Med Phys Source Type: research

Comparison of organ-at-risk sparing and plan robustness for spot-scanning proton therapy and volumetric modulated arc photon therapy in head-and-neck cancer.
CONCLUSIONS: MFO plans had improved OAR sparing but were less robust than SFO and VMAT plans, while SFO plans were more robust than MFO plans but resulted in less OAR sparing. Robustness of the MFO plans did not increase with more fields. PMID: 26520750 [PubMed - in process] (Source: Physica Medica)
Source: Physica Medica - November 1, 2015 Category: Physics Authors: Barten DL, Tol JP, Dahele M, Slotman BJ, Verbakel WF Tags: Med Phys Source Type: research

Luminescence imaging of water during proton-beam irradiation for range estimation.
CONCLUSIONS: Luminescence imaging during proton-beam irradiation is promising as an effective method for range estimation in proton therapy. PMID: 26520739 [PubMed - in process] (Source: Physica Medica)
Source: Physica Medica - November 1, 2015 Category: Physics Authors: Yamamoto S, Toshito T, Okumura S, Komori M Tags: Med Phys Source Type: research

Analysis of the track- and dose-averaged LET and LET spectra in proton therapy using the geant4 Monte Carlo code.
CONCLUSIONS: When the geant 4 particle tracking method is used to calculate the average LET values within targets with a small step limit, such as smaller than 500 μm, the authors recommend the use of LETt in the dose plateau region and LETd around the Bragg peak. For a large step limit, i.e., 500 μm, LETd is recommended along the whole Bragg curve. The transition point depends on beam parameters and can be found by determining the location where the gradient of the ratio of LETd and LETt becomes positive. PMID: 26520716 [PubMed - in process] (Source: Physica Medica)
Source: Physica Medica - November 1, 2015 Category: Physics Authors: Guan F, Peeler C, Bronk L, Geng C, Taleei R, Randeniya S, Ge S, Mirkovic D, Grosshans D, Mohan R, Titt U Tags: Med Phys Source Type: research

Characterization and validation of a Monte Carlo code for independent dose calculation in proton therapy treatments with pencil beam scanning.
Abstract We propose a method of creating and validating a Monte Carlo (MC) model of a proton Pencil Beam Scanning (PBS) machine using only commissioning measurements and avoiding the nozzle modeling. Measurements with a scintillating screen coupled with a CCD camera, ionization chamber and a Faraday Cup were used to model the beam in TOPAS without using any machine parameter information but the virtual source distance from the isocenter. Then the model was validated on simple Spread Out Bragg Peaks (SOBP) delivered in water phantom and with six realistic clinical plans (many involving 3 or more fields) on an anthr...
Source: Medical Physics - October 26, 2015 Category: Physics Authors: Fracchiolla F, Lorentini S, Widesott L, Schwarz M Tags: Phys Med Biol Source Type: research

Passive proton therapy vs. IMRT planning study with focal boost for prostate cancer
Conclusions: Protons delivered comparable doses to targets in dose homogeneity and conformity and spared normal tissues from intermediate-to-low doses better than IMRT did. Further improvement of dose sparing and changes in homogeneity and conformity may be achieved by reducing proton range uncertainties and from implementing intensity modulation. (Source: Radiation Oncology)
Source: Radiation Oncology - October 24, 2015 Category: Cancer & Oncology Authors: Inhwan YeoPrashanth NookalaIan GordonReinhard SchulteStanley BarnesAbiel GhebremedhinNing WangGary YangTed LingDavid BushJerry SlaterBaldev Patyal Source Type: research

Proton Therapy in Children – A Systematic Review of Clinical Effectiveness in 15 Pediatric Cancers
Because it spares many normal tissues and reduces the integral dose, proton therapy (PT) is the preferred tumor irradiation technique for treating childhood cancer. However, to the best of our knowledge, no systematic review of the clinical effectiveness of PT in children has been reported in the scientific literature. A systematic search for clinical outcome studies on PT published between 2007 and 2015 was performed in Medline (through OVID), EMBASE, and the Cochrane Library. Twenty-three primary studies were identified, including around 650 patients overall. (Source: International Journal of Radiation Oncology * Biology * Physics)
Source: International Journal of Radiation Oncology * Biology * Physics - October 18, 2015 Category: Radiology Authors: Roos Leroy, Nadia Benahmed, Frank Hulstaert, Nancy Van Damme, Dirk De Ruysscher Tags: Critical Review Source Type: research

Proton Therapy in Children: A Systematic Review of Clinical Effectiveness in 15 Pediatric Cancers
Because it spares many normal tissues and reduces the integral dose, proton therapy (PT) is the preferred tumor irradiation technique for treating childhood cancer. However, to the best of our knowledge, no systematic review of the clinical effectiveness of PT in children has been reported in the scientific literature. A systematic search for clinical outcome studies on PT published between 2007 and 2015 was performed in Medline (through OVID), EMBASE, and the Cochrane Library. Twenty-three primary studies were identified, including approximately 650 patients overall. (Source: International Journal of Radiation Oncology * Biology * Physics)
Source: International Journal of Radiation Oncology * Biology * Physics - October 18, 2015 Category: Radiology Authors: Roos Leroy, Nadia Benahmed, Frank Hulstaert, Nancy Van Damme, Dirk De Ruysscher Tags: Pediatrics Source Type: research

A phenomenological relative biological effectiveness (RBE) model for proton therapy based on all published in vitro cell survival data.
Abstract Proton therapy treatments are currently planned and delivered using the assumption that the proton relative biological effectiveness (RBE) relative to photons is 1.1. This assumption ignores strong experimental evidence that suggests the RBE varies along the treatment field, i.e. with linear energy transfer (LET) and with tissue type. A recent review study collected over 70 experimental reports on proton RBE, providing a comprehensive dataset for predicting RBE for cell survival. Using this dataset we developed a model to predict proton RBE based on dose, dose average LET (LETd) and the ratio of the linea...
Source: Physics in Medicine and Biology - October 13, 2015 Category: Physics Authors: McNamara AL, Schuemann J, Paganetti H Tags: Phys Med Biol Source Type: research

New frontiers in proton therapy: applications in breast cancer
Purpose of review: The aim of this article is to review published data on proton therapy in the multimodality treatment of breast cancer so as to provide an overview of the advantages and critical issues relating to this irradiation modality. Recent findings: In-silico studies show a clear advantage in terms of dose homogeneity to the target and dose reduction to the non-target structures including heart, lungs, and healthy breast tissues. Clinical studies have shown the feasibility of proton therapy in breast cancer and allowed optimizing the technique by using multiple beams and intensity modulation. Summary: Proton ther...
Source: Current Opinion in Oncology - October 12, 2015 Category: Cancer & Oncology Tags: BREAST CANCER: Edited by Giuseppe Curigliano Source Type: research

Positive perspectives from proton therapy
Emma Louise WaltonBiomedical Journal 2015 38(5):361-364In this issue of the Biomedical Journal, we take a look at some of the benefits of proton therapy, which is an emerging technique in cancer treatment and highlight an animal study, showing that a common fruit ripening agent is toxic when used in excessive doses. Finally, this issue includes reports that shed light on the genetics of stroke and childhood leukemia. (Source: Biomedical Journal)
Source: Biomedical Journal - October 9, 2015 Category: Biomedical Science Authors: Emma Louise Walton Source Type: research

Proton therapy
Chuan-Jong TungBiomedical Journal 2015 38(5):389-390 (Source: Biomedical Journal)
Source: Biomedical Journal - October 9, 2015 Category: Biomedical Science Authors: Chuan-Jong Tung Source Type: research

What are the potential benefits of using proton therapy in Taiwanese cancer patients?
Wei-Heng Kao, Yi-Liang Shen, Ji-Hong HongBiomedical Journal 2015 38(5):391-398The potential benefits of proton therapy have been established in pediatric cancer, skull base tumor, uveal melanoma, and other types of cancers. Western and Asian countries, however, have differences in the pattern of cancer incidence; this leads to the difference in patient demographics for proton therapy. Furthermore, the advancement of the scanning beam technique in proton therapy greatly expands the capability of proton therapy in disease sites with great complexity. In this review, we focus on the cancers with high incidence in Taiwan, base...
Source: Biomedical Journal - October 9, 2015 Category: Biomedical Science Authors: Wei-Heng KaoYi-Liang ShenJi-Hong Hong Source Type: research

MCNPX simulation of proton dose distributions in a water phantom
Conclusions: Careful modelling of MCS is necessary when proton disequilibrium exists. (Source: Biomedical Journal)
Source: Biomedical Journal - October 9, 2015 Category: Biomedical Science Authors: Chung-Chi LeeYun-Jing LeeShih-Kuan ChenBing-Hao ChiangChuan-Jong TungTsi-Chian Chao Source Type: research

Advances in Radiotherapy for Head and Neck Cancer [REVIEW ARTICLES]
Over the last few decades, significant improvements have been made in the radiotherapy (RT) treatment of head and neck malignancies. The progressive introduction of intensity-modulated RT and the use of multimodality imaging for target volume and organs at risk delineation, together with the use of altered fractionation regimens and concomitant administration of chemotherapy or targeted agents, have accompanied efficacy improvements in RT. Altogether, such improvements have translated into improvement in locoregional control and overall survival probability, with a decrease in the long-term adverse effects of RT and an imp...
Source: Journal of Clinical Oncology - October 8, 2015 Category: Cancer & Oncology Authors: Gregoire, Langendijk, Nuyts Tags: Radiation REVIEW ARTICLES Source Type: research

The quest for evidence for proton therapy: the model-based approach and precision medicine
Proton therapy can reduce normal tissue dose, but clinical benefit is still insufficiently demonstrated. Patients for whom there is no dosimetric difference in normal tissues of protons compared with photons will not benefit from proton therapy and should therefore neither undergo this therapy nor be included in clinical proton trials. Patient selection for prospective cohort studies as well as for randomized trials should be based on predictable benefit using multivariable NTCP models. (Source: International Journal of Radiation Oncology * Biology * Physics)
Source: International Journal of Radiation Oncology * Biology * Physics - October 8, 2015 Category: Radiology Authors: Joachim Widder, Arjen van der Schaaf, Philippe Lambin, Corrie A.M. Marijnen, Jean-Philippe Pignol, Coen R. Rasch, Ben J. Slotman, Marcel Verheij, Johannes A. Langendijk Tags: Clinical Investigation Source Type: research

The Quest for Evidence for Proton Therapy: Model-Based Approach and Precision Medicine
Reducing dose to normal tissues is the advantage of protons versus photons. We aimed to describe a method for translating this reduction into a clinically relevant benefit. (Source: International Journal of Radiation Oncology * Biology * Physics)
Source: International Journal of Radiation Oncology * Biology * Physics - October 8, 2015 Category: Radiology Authors: Joachim Widder, Arjen van der Schaaf, Philippe Lambin, Corrie A.M. Marijnen, Jean-Philippe Pignol, Coen R. Rasch, Ben J. Slotman, Marcel Verheij, Johannes A. Langendijk Tags: Clinical Investigation Source Type: research

Effect of elemental compositions on Monte Carlo dose calculations in proton therapy of eye tumors
Publication date: December 2015 Source:Radiation Physics and Chemistry, Volume 117 Author(s): Fatemeh S. Rasouli, S. Farhad Masoudi, Shiva Keshazare, David Jette Recent studies in eye plaque brachytherapy have found considerable differences between the dosimetric results by using a water phantom, and a complete human eye model. Since the eye continues to be simulated as water-equivalent tissue in the proton therapy literature, a similar study for investigating such a difference in treating eye tumors by protons is indispensable. The present study inquires into this effect in proton therapy utilizing Monte Carlo simul...
Source: Radiation Physics and Chemistry - October 6, 2015 Category: Physics Source Type: research

Improving 4D plan quality for PBS-based liver tumour treatments by combining online image guided beam gating with rescanning.
In conclusion, our results suggest image guided beam gating, combined with rescanning, is a feasible, effective and efficient motion mitigation approach for PBS-based liver tumour treatments. PMID: 26439493 [PubMed - as supplied by publisher] (Source: Physics in Medicine and Biology)
Source: Physics in Medicine and Biology - October 6, 2015 Category: Physics Authors: Zhang Y, Knopf AC, Weber DC, Lomax AJ Tags: Phys Med Biol Source Type: research

“Theoretical benefits of dynamic collimation in pencil beam scanning proton therapy for brain tumor”
Pencil beam scanning proton therapy for brain treatments may suffer from poor dose distribution conformity due to the relatively large spot sizes of the low energy beams necessary for these treatments. Collimation is expected to improve the normal tissue sparing by reducing the effective spot size near the target periphery for each energy layer. Comparisons of collimated and un-collimated plans yielded a systematic improvement of the dose distribution conformity. (Source: International Journal of Radiation Oncology * Biology * Physics)
Source: International Journal of Radiation Oncology * Biology * Physics - October 6, 2015 Category: Radiology Authors: Alexandra Moignier, Edgar Gelover, Dongxu Wang, Ryan Flynn, Maura Kirk, Liyong Lin, Timothy Solberg, Alexander Lin, Daniel Hyer Tags: Physics Contribution Source Type: research

Theoretical Benefits of Dynamic Collimation in Pencil Beam Scanning Proton Therapy for Brain Tumors: Dosimetric and Radiobiological Metrics
To quantify the dosimetric benefit of using a dynamic collimation system (DCS) for penumbra reduction during the treatment of brain tumors by pencil beam scanning proton therapy (PBS PT). (Source: International Journal of Radiation Oncology * Biology * Physics)
Source: International Journal of Radiation Oncology * Biology * Physics - October 6, 2015 Category: Radiology Authors: Alexandra Moignier, Edgar Gelover, Dongxu Wang, Blake Smith, Ryan Flynn, Maura Kirk, Liyong Lin, Timothy Solberg, Alexander Lin, Daniel Hyer Tags: Physics Contribution Source Type: research

Impediments to Comparative Clinical Trials with Proton Therapy
This editorial review characterizes aspects of clinical trials that represent impediments to conducting such trials of proton therapy. (Source: International Journal of Radiation Oncology * Biology * Physics)
Source: International Journal of Radiation Oncology * Biology * Physics - October 2, 2015 Category: Radiology Authors: James D. Cox Tags: Clinical Investigation Source Type: research

Monte Carlo simulation of prompt γ-ray emission in proton therapy using a specific track length estimator.
Monte Carlo simulation of prompt γ-ray emission in proton therapy using a specific track length estimator. Phys Med Biol. 2015 Oct 1;60(20):8067-8086 Authors: El Kanawati W, Létang JM, Dauvergne D, Pinto M, Sarrut D, Testa É, Freud N Abstract A Monte Carlo (MC) variance reduction technique is developed for prompt-γ emitters calculations in proton therapy. Prompt-γ emitted through nuclear fragmentation reactions and exiting the patient during proton therapy could play an important role to help monitoring the treatment. However, the estimation of the number and the energy...
Source: Physics in Medicine and Biology - October 1, 2015 Category: Physics Authors: El Kanawati W, Létang JM, Dauvergne D, Pinto M, Sarrut D, Testa É, Freud N Tags: Phys Med Biol Source Type: research

A virtual simulator designed for collision prevention in proton therapy.
CONCLUSIONS: The developed software will be useful in improving patient safety and clinical efficiency of proton therapy. PMID: 26429277 [PubMed - in process] (Source: Physica Medica)
Source: Physica Medica - October 1, 2015 Category: Physics Authors: Jung H, Kum O, Han Y, Park HC, Kim JS, Choi DH Tags: Med Phys Source Type: research

Gold nanoparticle induced vasculature damage in radiotherapy: Comparing protons, megavoltage photons, and kilovoltage photons.
CONCLUSIONS: GNPs can potentially be used to enhance radiation therapy by causing vasculature damage through high dose spikes caused by the addition of GNPs especially for hypofractionated treatment. If GNPs are designed to actively accumulate at the tumor vasculature walls, vasculature damage can be increased significantly. The largest enhancement is seen using kilovoltage photons due to the photoelectric effect. Although no significant average dose enhancement was observed for the whole vasculature structure for both MV photons and protons, they can cause high local dose escalation (>15 Gy) to areas of the blood vesse...
Source: Physica Medica - October 1, 2015 Category: Physics Authors: Lin Y, Paganetti H, McMahon SJ, Schuemann J Tags: Med Phys Source Type: research

Projections onto the Pareto surface in multicriteria radiation therapy optimization.
CONCLUSIONS: There are situations when Pareto navigation leaves room for improvement in OAR sparing and dose conformity, for example, if the approximation of the Pareto surface is coarse or the problem formulation has too permissive constraints. A projection onto the Pareto surface can identify an inaccurate Pareto surface representation and, if necessary, improve the quality of the navigated plan. PMID: 26429260 [PubMed - in process] (Source: Physica Medica)
Source: Physica Medica - October 1, 2015 Category: Physics Authors: Bokrantz R, Miettinen K Tags: Med Phys Source Type: research

Theoretical detection threshold of the proton-acoustic range verification technique.
CONCLUSIONS: The proton-acoustic process was simulated using a realistic model and the minimal detection limit was established for proton-acoustic range validation. These limits correspond to a best case scenario with a single large detector with no losses and detector thermal noise as the sensitivity limiting factor. Our study indicated practical proton-acoustic range verification may be feasible with approximately 5 × 10(6) protons/pulse and beam current. PMID: 26429247 [PubMed - in process] (Source: Physica Medica)
Source: Physica Medica - October 1, 2015 Category: Physics Authors: Ahmad M, Xiang L, Yousefi S, Xing L Tags: Med Phys Source Type: research

Mobile Spine Chordoma: Results of 166 Patients
Chordomas are primary spinal tumors that grow via an indolent course, but have devastating effects on patients’ lives. These lesions are chemoresistant, moderately radiosensitive to conventional radiotherapy and emerging evidence suggests that proton therapy may be effective. However, en bloc surgical resection remains the preferred treatment to maximize patient outcomes. While multiple studies have investigated the outcomes following en bloc resection of chordomas in the sacrum, there have been few large-scale studies of patients with chordoma of the mobile spine. (Source: The Spine Journal)
Source: The Spine Journal - September 23, 2015 Category: Orthopaedics Authors: Daniel M. Sciubba, Ziya L. Gokaslan, Patricia L. Zadnik, Niccole M. Germscheid, C. Rory Goodwin, Jean-Paul Wolinsky, Chetan Bettegowda, Mari L. Groves, Alessandro Luzzati, Charles G. Fisher, Peter P. Varga, Mark B. Dekutoski, Michelle J. Clarke, Michael G Source Type: research

A retrospective evaluation of the benefit of referring pediatric cancer patients to an external proton therapy center
BackgroundPediatric cancer patients requiring radiation therapy (RT) have been routinely assessed and referred to proton therapy (PT) at an external institution. The benefit of the delivered PT compared to the state‐of‐the‐art intensity modulated x‐ray RT (XT) at the home institution was evaluated. ProcedureTwenty‐four consecutive children referred for PT during 2010–2013 for craniospinal (CSI, n = 10), localized intracranial (IC, n = 7), head/neck (HN, n = 4) or parameningeal (PM, n = 3) lesions were included. The median age was 8 years (2–16 ye...
Source: Pediatric Blood and Cancer - September 23, 2015 Category: Cancer & Oncology Authors: Per Munck af Rosenschold, Svend A. Engelholm, Patrik N. Brodin, Morten Jørgensen, David R. Grosshans, Ronald X. Zhu, Matthew Palmer, Cody N. Crawford, Anita Mahajan Tags: Research Article Source Type: research

Modern clinical research: How rapid learning health care and cohort multiple randomised clinical trials complement traditional evidence based medicine.
DISCUSSION: Truly personalised cancer treatment is the goal in modern radiotherapy. However, personalised cancer treatment is also an immense challenge. The vast variety of both cancer patients and treatment options makes it extremely difficult to determine which decisions are optimal for the individual patient. Nevertheless, rapid learning health care and cohort multiple randomised controlled trial design are two approaches (among others) that can help meet this challenge. PMID: 26395528 [PubMed - as supplied by publisher] (Source: Acta Oncologica)
Source: Acta Oncologica - September 23, 2015 Category: Cancer & Oncology Authors: Lambin P, Zindler J, Vanneste B, van de Voorde L, Jacobs M, Eekers D, Peerlings J, Reymen B, Larue RT, Deist TM, de Jong EE, Even AJ, Berlanga AJ, Roelofs E, Cheng Q, Carvalho S, Leijenaar RT, Zegers CM, van Limbergen E, Berbee M, van Elmpt W, Oberije C, Tags: Acta Oncol Source Type: research

Paediatric Chordomas
Paediatric chordomas are rare malignant tumours arising from primitive notochordal remnants with a high rate of recurrence. Only 5 % of them occur in the first two decades such less than 300 paediatric cases have been reported so far in the literature. In children, the average age at diagnosis is 10 years with a male-to-female ratio closed to 1. On the opposite to adults, the majority of paediatric chordomas are intracranial, characteristically centered on the sphenooccipital synchondrosis. Metastatic spread seems to be the prerogative of the under 5-year-old children with more frequent sacro-coccygeal locations ...
Source: Orphanet Journal of Rare Diseases - September 22, 2015 Category: Internal Medicine Authors: Kévin BeccariaChristian Sainte-RoseMichel ZerahStéphanie Puget Source Type: research

Proton irradiation impacts age-driven modulations of cancer progression influenced by immune system transcriptome modifications from splenic tissue
Age plays a crucial role in the interplay between tumor and host, with additional impact due to irradiation. Proton irradiation of tumors induces biological modulations including inhibition of angiogenic and immune factors critical to ‘hallmark’ processes impacting tumor development. Proton irradiation has also provided promising results for proton therapy in cancer due to targeting advantages. Additionally, protons may contribute to the carcinogenesis risk from space travel (due to the high proportion of high-energy protons in space radiation). Through a systems biology approach, we investigated how host tissu...
Source: Journal of Radiation Research - September 21, 2015 Category: Physics Authors: Wage, J., Ma, L., Peluso, M., Lamont, C., Evens, A. M., Hahnfeldt, P., Hlatky, L., Beheshti, A. Tags: Biology Source Type: research

Initial Report of a Prospective Dosimetric and Clinical Feasibility Trial Demonstrates Potential of Protons to Increase the Therapeutic Ratio in Breast Cancer Compared with Photons
In this prospective study of radiation therapy for intact and post-mastectomy breast cancer requiring regional nodal irradiation, proton therapy improved heart and lung dose in all patients (right and left sided). For left-sided patients, median mean cardiac dose decreased from 5.9 Gy with conventional therapy to 0.6 Gy with proton therapy. For all patients, ipsilateral lung V5 and V20 were significantly reduced with proton therapy and better IMN and level II axillary coverage was achieved. (Source: International Journal of Radiation Oncology * Biology * Physics)
Source: International Journal of Radiation Oncology * Biology * Physics - September 21, 2015 Category: Radiology Authors: Julie A. Bradley, Roi Dagan, Meng Wei Ho, Michael Rutenberg, Christopher G. Morris, Zuofeng Li, Nancy P. Mendenhall Tags: Clinical Investigation Source Type: research

Initial Report of a Prospective Dosimetric and Clinical Feasibility Trial Demonstrates the Potential of Protons to Increase the Therapeutic Ratio in Breast Cancer Compared With Photons
To compare dosimetric endpoints between proton therapy (PT) and conventional radiation and determine the feasibility of PT for regional nodal irradiation (RNI) in women with breast cancer. (Source: International Journal of Radiation Oncology * Biology * Physics)
Source: International Journal of Radiation Oncology * Biology * Physics - September 21, 2015 Category: Radiology Authors: Julie A. Bradley, Roi Dagan, Meng Wei Ho, Michael Rutenberg, Christopher G. Morris, Zuofeng Li, Nancy P. Mendenhall Tags: Clinical Investigation Source Type: research

Incidence of CNS Injury for a Cohort of 111 Patients Treated with Proton Therapy for Medulloblastoma; LET and RBE Associations for Areas of Injury
This report investigates the incidence of CNS injury in a large cohort of medulloblastoma patients treated with craniospinal irradiation by proton radiotherapy. An overall incidence of 3.6% was found. No clear correlation was found between the sites of toxicity and elevated RBE due to higher linear energy transfer values. (Source: International Journal of Radiation Oncology * Biology * Physics)
Source: International Journal of Radiation Oncology * Biology * Physics - September 17, 2015 Category: Radiology Authors: Drosoula Giantsoudi, Roshan V. Sethi, Beow Y. Yeap, Bree R. Eaton, David H. Ebb, Paul A. Caruso, Otto Rapalino, Yen-Lin E. Chen, Judith Adams, Torunn I. Yock, Nancy J. Tarbell, Harald Paganetti, Shannon M. MacDonald Tags: Clinical Investigation Source Type: research

Tumour Response in Uveal Melanomas Treated with Proton Beam Therapy
Post-proton therapy surveillance of uveal melanomas relies on decreased thickness on repeat ultrasound B every 6 months for 2 years and yearly thereafter. Earlier pseudoprogression, a phenomenon described in other tumour types within the first months of irradiation, can also be observed in uveal melanomas and may lead to inappropriate enucleation. The Collaborative Ocular Melanoma Study (COMS) has defined ultrasound criteria to identify tumour progression after brachytherapy. We aimed to determine the reliability of ultrasound as a means to measure tumour height after proton therapy and predict local relapse. (Source: Clinical Oncology)
Source: Clinical Oncology - September 15, 2015 Category: Radiology Authors: C. Maschi, J. Thariat, J. Herault, J.-P. Caujolle Tags: Original Article Source Type: research

The ANDANTE project: a multidisciplinary approach to neutron RBE
The usual method for estimating the risk from exposure to neutrons uses the concept of relative biological effectiveness (RBE) compared with the risk from photons, which is better known. RBE has been evaluated using cellular and animal models. But this causes difficulties in applying the concept to humans. The ANDANTE project takes a new approach using three different disciplines in parallel: Physics: a track structure model is used to contrast the patterns of damage to cellular macro-molecules from neutrons compared with photons. The simulations reproduce the same energy spectra as are used in the other two approaches. St...
Source: Radiation Protection Dosimetry - September 14, 2015 Category: Radiology Authors: Ottolenghi, A., Baiocco, G., Smyth, V., Trott, K., on behalf of the ANDANTE Consortium Tags: Radiation risk assessment on earth and in space Source Type: research

Single-energy intensity modulated proton therapy.
Abstract In this note, an intensity modulated proton therapy (IMPT) technique, based on the use of high single-energy (SE-IMPT) pencil beams, is described.The method uses only the highest system energy (226 MeV) and only lateral penumbra to produce dose gradient, as in photon therapy. In the study, after a preliminary analysis of the width of proton pencil beam penumbras at different depths, SE-IMPT was compared with conventional IMPT in a phantom containing titanium inserts and in a patient, affected by a spinal chordoma with fixation rods.It was shown that SE-IMPT has the potential to produce a sharp dose gradie...
Source: Physica Medica - September 9, 2015 Category: Physics Authors: Farace P, Righetto R, Cianchetti M Tags: Phys Med Biol Source Type: research

Late radiation toxicity in Hodgkin lymphoma patients: proton therapy’s potential
In 2010, all young patients treated for intrathoracic Hodgkin lymphoma (HL) at one of 10 radiotherapy centers in the province of Quebec received 3D conformal photon therapy. These patients may now be at risk for late effects of their treatment, notably secondary malignancies and cardiac toxicity. We hypothesized that more complex radiotherapy, including intensity-modulated proton therapy (IMPT) and possibly IMRT (in the form of helical tomotherapy (HT)), could benefit these patients. With institutional review board approval at 10 institutions, all treatment plans for patients under the age of 30 treated for HL during a six...
Source: Journal of Applied Clinical Medical Physics - September 8, 2015 Category: Physics Source Type: research

Utilization of optical tracking to assess efficacy of intracranial immobilization techniques in proton therapy
We present a quantitative methodology to measure head interfraction movements within intracranial masks of commercial immobilization devices used for proton radiotherapy. A three-points tracking (3PtTrack) method was developed to measure the mask location for each treatment field over an average of 10 fractions for seven patients. Five patients were treated in supine with the Qfix Base-of-Skull (BoS) headframe, and two patients were treated in prone with the CIVCO Uni-frame baseplate. Patients were first localized by an in-room, image-guidance (IG) system, and then the mask location was measured using the 3PtTrack method. ...
Source: Journal of Applied Clinical Medical Physics - September 8, 2015 Category: Physics Source Type: research

Dose perturbation effect of metallic spinal implants in proton beam therapy
The purpose of this study was to investigate the effect of dose perturbations for two metallic spinal screw implants in proton beam therapy in the perpendicular and parallel beam geometry. A 5.5 mm (diameter) by 45 mm (length) stainless steel (SS) screw and a 5.5 mm by 35 mm titanium (Ti) screw commonly used for spinal fixation were CT-scanned in a hybrid phantom of water and solid water. The CT data were processed with an orthopedic metal artifact reduction (O-MAR) algorithm. Treatment plans were generated for each metal screw with a proton beam oriented, first parallel and then perpendicular, to the longitudinal axis of ...
Source: Journal of Applied Clinical Medical Physics - September 8, 2015 Category: Physics Source Type: research

Use of diverging apertures to minimize the edge scatter in passive scattering proton therapy
The purpose of this study was to evaluate the use of diverging-cut aperture to minimize collimator contamination in proton therapy. Two sets of apertures with nondivergent and divergent edge were fabricated to produce a 10 cm × 10 cm field at the radiation isocenter of a single-room proton therapy unit. Transverse profiles were acquired in a scanning water tank with both aperture sets. Up to 9.5% extra dose was observed from aperture scattering near the field edges with the nondivergent aperture set at 2 cm above the water surface and remained 3.0% at depth of 10 cm. For the divergent set, the contamination was reduc...
Source: Journal of Applied Clinical Medical Physics - September 8, 2015 Category: Physics Source Type: research

Impact of grid size on uniform scanning and IMPT plans in XiO treatment planning system for brain cancer
In conclusion, the difference in the calculated point dose between the smallest grid size (1 mm) and the largest grid size (3 mm) in phantom for USPT was typically less than 0.1%. Patient study results showedthat the decrease in grid size slightly increased the PTV maximum dose in both the USPT and IMPT plans. However, no distinct trend was obtained between the absolute difference in dosimetric parameter and dose calculation grid size for the OARs. Grid size has a large effect on dose calculation efficiency, and use of 2 mm or less grid size can increase the dose calculation time significantly. It is recommended to use gri...
Source: Journal of Applied Clinical Medical Physics - September 8, 2015 Category: Physics Source Type: research

Feasibility of dominant intraprostatic lesion boosting using advanced photon-, proton- or brachytherapy
This study aimed to assess the feasibility of DIL boosting for volumetric modulated arc therapy (VMAT), intensity modulated proton therapy (IMPT) and high dose rate brachytherapy (HDR-BT). (Source: Radiotherapy and Oncology)
Source: Radiotherapy and Oncology - September 6, 2015 Category: Radiology Authors: Piotr Andrzejewski, Peter Kuess, Barbara Knäusl, Katja Pinker, Petra Georg, Johannes Knoth, Daniel Berger, Christian Kirisits, Gregor Goldner, Thomas Helbich, Richard Pötter, Dietmar Georg Tags: Original article Source Type: research

Feasibility of dominant intraprostatic lesion boosting using advanced photon-, proton- or brachytherapy.
CONCLUSIONS: DIL boosting was found to be feasible with all investigated techniques. Although OAR doses were higher than for standard treatment approach, the risk levels were reasonably low. HDR-BT was superior to VMAT and IMPT, both in terms of OAR sparing and DIL boosting. PMID: 26349588 [PubMed - as supplied by publisher] (Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology)
Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology - September 6, 2015 Category: Radiology Authors: Andrzejewski P, Kuess P, Knäusl B, Pinker K, Georg P, Knoth J, Berger D, Kirisits C, Goldner G, Helbich T, Pötter R, Georg D Tags: Radiother Oncol Source Type: research

Investigation of ectopic recurrent skull base and cervical chordomas: The Institut Curie's proton therapy center experience
ConclusionOur study emphasizes an urgent need for prediction and early diagnosis of ectopic relapses in patients with cervical and skull base chordoma to improve accuracy of their aggressive treatments. © 2015 Wiley Periodicals, Inc. Head Neck, 2015 (Source: Head and Neck)
Source: Head and Neck - September 4, 2015 Category: ENT & OMF Authors: Guillaume Vogin, Valentin Calugaru, Stéphanie Bolle, Bernard George, Guillaume Oldrini, Jean‐Louis Habrand, Hamid Mammar, Rémi Dendale, Julia Salleron, Georges Noël, Loïc Feuvret Tags: Original Article Source Type: research

NTCP reduction for advanced head and neck cancer patients using proton therapy for complete or sequential boost treatment versus photon therapy.
CONCLUSIONS: The use of IMPT generally reduces the expected toxicity risk while maintaining good tumor coverage in the examined HNSCC patients. A mixed modality treatment using IMPT solely for a sequential boost reduces the risk by 10% only in rare cases. In contrast, pure IMPT treatment may be reasonable for about half of the examined patient cohort considering the toxicities xerostomia and dysphagia, if a feasible strategy for patient anatomy changes is implemented. PMID: 26340301 [PubMed - as supplied by publisher] (Source: Acta Oncologica)
Source: Acta Oncologica - September 4, 2015 Category: Cancer & Oncology Authors: Jakobi A, Stützer K, Bandurska-Luque A, Löck S, Haase R, Wack LJ, Mönnich D, Thorwarth D, Perez D, Lühr A, Zips D, Krause M, Baumann M, Perrin R, Richter C Tags: Acta Oncol Source Type: research

Radiotherapy dosimetry audit: three decades of improving standards and accuracy in UK clinical practice and trials.
Abstract Dosimetry audit plays an important role in the development and safety of radiotherapy. National and large scale audits are able to set, maintain and improve standards, as well as having the potential to identify issues which may cause harm to patients. They can support implementation of complex techniques and can facilitate awareness and understanding of any issues which may exist by benchmarking centres with similar equipment. This review examines the development of dosimetry audit in the UK over the last 30 years, including the involvement of the UK in international audits. A summary of audit results is...
Source: The British Journal of Radiology - September 2, 2015 Category: Radiology Authors: Clark CH, Aird EG, Bolton S, Miles EA, Nisbet A, Snaith JA, Thomas RA, Venables K, Thwaites DI Tags: Br J Radiol Source Type: research

Impact of IV Contrast Enhancement Phase on Target Definition for Hepatocellular Carcinoma(HCC) and Intrahepatic Cholangiocarcinoma(IHC): Observations from Patients Enrolled on a Prospective Phase II Trial
Conclusions Variability between GTVs on multiphasic CT scans could not be overcome with a 5-mm expansion of either the smallest GTV or the best-visualized GTV. Assessment of all available IV contrast phases is essential to accurately define the GTV. (Source: Practical Radiation Oncology)
Source: Practical Radiation Oncology - August 29, 2015 Category: Cancer & Oncology Source Type: research