This feasibility study confirmed the initial safety and efficacy of a novel carbon-ion radiotherapy (CIRT) using linear energy transfer (LET) painting for head neck cancer. is first step toward establishing CIRT with LET in clinical practice making it standard future.

A method to establish the relationship between CT number and effective density for therapeutic radiations is proposed. We approximated body tissues mixtures of muscle, air, fat bone. Consequently, can be calibrated only with a scan their substitutes, which we chose water, ethanol potassium phosphate solution, respectively. With simple specific corrections non-equivalencies calibration accuracy 1% will achieved. tested some biological materials verify that proposed would offer accuracy,...

Secondary neutron ambient dose equivalents per the treatment absorbed in passive carbon-ion and proton radiotherapies were measured using a rem meter, WENDI-II at two radiotherapy facilities four Japan. Our results showed that (1) equivalent is lower than radiotherapy, (2) difference to among within factor of 3 depending on operational beam setting used facility arrangement line, regardless method for making laterally uniform irradiation field: double scattering or single-ring wobbling...

The local control rate of chondrosarcomas treated with carbon-ion radiotherapy (CIRT) worsens as tumour size increases, possibly because the intra-tumoural linear energy transfer (LET) distribution. This study aimed to evaluate relationship between recurrence and LET distribution in CIRT.Thirty patients CIRT for grade 2 chondrosarcoma were included. Dose-averaged (LETd) was calculated by treatment planning system, LETd volume (PTV) evaluated.The mean value PTV similar cases without...

Dose-averaged linear energy transfer (LETd) is one of the important factors in determining clinical outcomes for carbon-ion radiation therapy. Innovative LET painting (LP) has been developed as an advanced form conventional intensity modulated therapy (IMIT) at QST Hospital. The study had 2 motivations: to increase minimum LETd (LETdmin) and improve uniformity distribution within gross tumor volume (GTV) by using LP treatment plans patients with head neck cancer while maintaining relative...

We implemented the simplified Monte Carlo (SMC) method on graphics processing unit (GPU) architecture under computer-unified device platform developed by NVIDIA. The GPU-based SMC was clinically applied for four patients with head and neck, lung, or prostate cancer. results were compared to those obtained a traditional CPU-based respect computation time discrepancy. In CPU- calculations, estimated mean statistical errors of calculated doses in planning target volume region within 0.5% rms....

Purpose: Respiration‐gated irradiation for a moving target requires longer time to deliver single fraction in proton radiotherapy (PRT). Ultrahigh dose rate (UDR) beam, which is 10–100 times higher than that used current clinical practice, has been investigated daily breath hold duration. The purpose of this study investigate the survival curve and relative biological effectiveness (RBE) such an ultrahigh beam their linear energy transfer (LET) dependence. Methods: HSG cells were irradiated...

Cellular responses to proton beam irradiation are not yet clearly understood, especially differences in the relative biological effectiveness (RBE) of high-energy beams depending on position Spread-Out Bragg Peak (SOBP). Towards this end, we investigated effect a target cells placed at different positions SOBP, using two human esophageal cancer cell lines with differing radiosensitivities. Two (OE21, KYSE450) radiosensitivities were irradiated 235-MeV 4 SOBP (position #1: At entry; #2:...

It is important for proton therapy to calculate dose distributions accurately in treatment planning. Dose calculations the body planning are converted water, and then generally evaluated by measurements water. In this paper, were realized a phantom simulating clinical heterogeneity. Both calculated two calculation methods, range-modulated pencil beam algorithm (RMPBA) simplified Monte Carlo (SMC) method, water same methods verified experimentally through comparison with measured...

The metal oxide semiconductor field-effect transistor (MOSFET) dosimeter has been widely studied for use as a patient dose verification. major advantage of this detector is its size, which acts point dosimeter, and also ease use. commercially available TN502RD MOSFET manufactured by Thomson Nielsen never used proton dosimetry. Therefore we the first time in measurements. In study, was irradiated with 190 MeV therapeutic beams. We experimentally evaluated reproducibility, linearity, fading...

Treatment planning for proton tumor therapy requires a fast and accurate dose-calculation method. We have implemented simplified Monte Carlo (SMC) method in the treatment system of National Cancer Center Hospital East double-scattering beam delivery scheme. The SMC takes into account scattering effect materials more accurately than pencil algorithm by tracking individual paths. confirmed that reproduced measured dose distributions heterogeneous slab phantom better When applied to complex...

In proton beam therapy, changes in the range due to lateral heterogeneity may cause serious errors dose distribution. present study, pencilbeam redefinition algorithm (PBRA) was applied therapy address problem of density heterogeneity. calculation, phase-space parameters were characterized for multiple (i.e. energy) bins given pencil beams. The particles that included each transported and redefined periodically until they had stopped. beams formed a detouring path different from...

To assess the feasibility of proton beam therapy for patients with locally advanced non-small lung cancer. The dosimetry was analyzed retrospectively to calculate doses organs at risk, such as lung, heart, esophagus and spinal cord. A dosimetric comparison between dummy photon radiotherapy (three-dimensional conformal radiotherapy) plans performed. Dummy intensity-modulated were also generated whom curative three-dimensional could not be generated. Overall, 33 stage III cell cancer treated...

In this study, the survival fraction (SF) and relative biological effectiveness (RBE) of pancreatic cancer cells exposed to spread-out Bragg peak helium, carbon, oxygen, neon ion beams are estimated from measured microdosimetric spectra using a microdosimeter application kinetic (MK) model. To measure spectra, 3D mushroom silicon-on-insulator connected low noise readout electronics (MicroPlus probe) was used. The parameters MK model were determined for such that calculated SFs reproduced...

When in vivo proton dosimetry is performed with a metal‐oxide semiconductor field‐effect transistor (MOSFET) detector, the response of detector depends strongly on linear energy transfer. The present study reports practical method to correct MOSFET for transfer dependence by using simplified Monte Carlo dose calculation (SMC). A depth‐output curve mono‐energetic beam polyethylene was measured detector. This used calculate output distributions SMC . value at an arbitrary point compared...

Taking advantage of the continuous, high-intensity beam cyclotron at National Cancer Center Hospital East, we developed a continuous line scanning system (CLSS) prototype for prostate cancer in collaboration with Sumitomo Heavy Industries, Ltd (Tokyo, Japan).The CLSS modulates dose distribution each energy level by varying speed while keeping intensity constant through beam-intensity control and rapid on/off beam-switching system. In addition, alignment to improve precision position. The is...

Proton therapy has the physical advantage of a Bragg peak that can provide better dose distribution than conventional x-ray therapy. However, radiation exposure normal tissues cannot be ignored because it is likely to increase risk secondary cancer. Evaluating neutrons generated by interaction proton beam with treatment beam-line structure necessary; thus, performing optimization protection in required. In this research, organ and energy spectrum were calculated from using Monte Carlo...

To perform the final quality assurance of our fluoroscopic-based markerless tumor tracking for gated carbon-ion pencil beam scanning (C-PBS) radiotherapy using a rotating gantry system, we evaluated geometrical accuracy and moving chest phantom with simulated respiration.The positions dynamic flat panel detector (DFPD) x-ray tube are subject to changes due sag. compensate this, generated calibration table (gantry flex map) in 15° angle steps by bundle adjustment method. We five metrics: (a)...

Abstract Purpose To evaluate the outcomes of particle therapy in cancer patients with cardiac implantable electronic devices (CIEDs). Materials and methods From April 2001 to March 2013, 19,585 were treated proton beam (PBT) or carbon ion (CIT) at 8 institutions. Of these, 69 (0.4%, PBT 46, CIT 22, + 1) CIEDs (64 pacemakers, 4 cardioverter defibrillators, 1 a resynchronization defibrillator) retrospectively reviewed. All this study passive scattering type therapy. Results Six (13%) 47...