Publications by authors named "Sayuri Bou"

We report here the long-term results of marker-less respiratory-gated proton therapy (PT), without fiducial markers for hepatocellular carcinoma (HCC), which was planned using a four-dimensional computed tomography technique. Local tumor control (LTC) and overall survival (OS) were estimated using the Kaplan-Meier method. Toxicity was graded per CTCAE v5.

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This study aims to investigate the effects of the position correction of size-specific dose estimates (SSDE) on patient dose estimation in cone beam computed tomography (CBCT). The relationship between the phantom position and absorbed dose in the right breast was studied using optically stimulated luminescence dosimeters and a simulated human body phantom. The effect of position correction for CT dose index (CTDI) on SSDE was investigated in 51 patients who underwent right breast irradiation by comparing the SSDE with position correction and SSDE without position correction.

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This study aims to investigate the influence of the phantom position on weighted computed tomography dose index (CTDI ) in cone beam computed tomography (CBCT) when assuming breast irradiation. Computed tomography dose index (CTDI) was measured by the x-ray volume imaging of CBCT using parameters for image-guided radiation therapy (IGRT) in right breast irradiation. The measurement points of CTDI ranged from 0 (center) to 16 cm in the right-left (RL) direction, and from 0 (center) to 7.

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A 67-year-old man visited our hospital due to progressing appetite loss and fever. He presented with a fist-sized palpable mass in his right hypochondrium. Abdominal CT showed a 10 cm diameter tumor that originated from the gall bladder infiltrating the abdominal wall, liver, duodenum, and colon.

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Purpose: The purpose of this study was to analyze the respiratory motion of each segment of the liver in patients with or without a history of abdominal surgery using four-dimensional computed tomography.

Materials And Methods: In total, 57 patients treated for abdominal tumors using proton beam therapy were enrolled. Eighteen patients had a history of abdominal surgery and 39 did not.

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Purpose: We quantified interfractional movements of the prostate, seminal vesicles (SVs), and rectum during computed tomography (CT) image-guided proton therapy for prostate cancer and studied the range variation in opposed lateral proton beams.

Materials/methods: We analyzed 375 sets of daily CT images acquired throughout the proton therapy treatment of ten patients. We analyzed daily movements of the prostate, SVs, and rectum by simulating three image-matching strategies: bone matching, prostate center (PC) matching, and prostate-rectum boundary (PRB) matching.

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We evaluated the effectiveness and toxicity of proton beam therapy (PBT) for hepatocellular carcinomas (HCC) >5 cm without fiducial markers using four-dimensional CT (4D-CT) planning. The subjects were 29 patients treated at our hospital between March 2011 and March 2015. The median total dose was 76 Cobalt Gray Equivalents (CGE) in 20 fractions (range; 66-80.

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Purpose: To evaluate the effectiveness of CT image-guided proton radiotherapy for prostate cancer by analyzing the positioning uncertainty and assessing daily dose change due to anatomical variations.

Materials And Methods: Patients with prostate cancer were treated by opposed lateral proton beams based on a passive scattering method using an in-room CT image-guided system. The system employs a single couch for both CT scanning and beam delivery.

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The efficacy of proton beam therapy (PBT) for hepatocellular carcinoma (HCC) has been reported, but insertion of fiducial markers in the liver is usually required. We evaluated the efficacy and toxicity of respiratory-gated PBT without fiducial markers for HCC located within 2 cm of the gastrointestinal tract. From March 2011 to December 2015 at our institution, 40 patients were evaluated (median age, 72 years; range, 38-87 years).

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The patient was a 47-year-old man who had been found to have an intrathoracic lipoma arising from the left chest wall during a routine physical examination 4 years previously, and had been followed-up. He visited our hospital because of left chest pain. Since the tumor had enlarged, he was scheduled for surgery.

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