Toshiyuki Shirai

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We try to elucidate whether a carbon ion beam alone or in combination with gemcitabine has advantages over X-ray in targeting putative pancreatic cancer stem-like cells (CSCs) in vitro and in vivo. Colony, spheroid formation and tumorigenicity assays confirmed that CD44+/ESA+ cells sorted from PANC1 and PK45 cells have more CSC properties than CD44-/ESA-(More)
Our institute has constructed a new treatment facility for carbon ion scanning beam therapy. The first clinical trials were successfully completed at the end of November 2011. To evaluate patient setup accuracy, positional errors between the reference Computed Tomography (CT) scan and final patient setup images were calculated using 2D-3D registration(More)
Amplitude-based gating aids treatment planning in scanned particle therapy because it gives better control of uncertainty with the gate window. We have installed an X-ray fluoroscopic imaging system in our treatment room for clinical use with an amplitude-based gating strategy. We evaluated the effects of this gating under realistic organ motion conditions(More)
To increase the accuracy of carbon ion beam scanning therapy, we have developed a graphical user interface-based digitally-reconstructed radiograph (DRR) software system for use in routine clinical practice at our center. The DRR software is used in particular scenarios in the new treatment facility to achieve the same level of geometrical accuracy at the(More)
BACKGROUND To moving lung tumors, we applied a respiratory-gated strategy to carbon-ion pencil beam scanning with multiple phase-controlled rescanning (PCR). In this simulation study, we quantitatively evaluated dose distributions based on 4-dimensional CT (4DCT) treatment planning. METHODS Volumetric 4DCTs were acquired for 14 patients with lung tumors.(More)
Purpose: The aim of this study was to clarify the cell survival in human salivary gland (HSG) cells under oxic condition after 290 MeV/nucleon carbon-ion beams and 200 kV X-rays. Moreover, we examined OH radical-mediated indirect actions from either SOBP carbon beams or photon beams on cellular lethality. Materials and methods: Cell culture: The HSG cells(More)
Executive Directors 1. Cell-permeable intrinsic cellular inhibitors of apoptosis protect and rescue intestinal epithelial cells from radiation-induced cell death. Research on Cancer Therapy with Carbon Beams 1. Carbon ion radiotherapy in Japan: an assessment of 20 years of clinical experience. 2. Usefulness of J-CAPRA score for high-risk prostate cancer(More)
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