Publications by authors named "Shigeki Ito"

Purpose: We have developed a forceps-type coincidence radiation detector for supporting lymph node dissection in esophageal cancer treatment. For precise detecting, this study aims to measure the 2D point-spread function of the detector at three difference tip angles, to devise a method to determine the position of a point source using the 2D point-spread function.

Method: The 2D sensitivity distribution on the surface of the detector was investigated to assess sensitivity variation caused by differences in the relative positions of the detector and radiation source.

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Immune checkpoint inhibitors (ICI) are promising therapeutic agents for relapsed or refractory classical Hodgkin's lymphoma (RRcHL). This retrospective study evaluated patients with RRcHL registered in the clinical research program Tohoku-Hematology-Forum-26, between 2016 and 2020, and treated with ICI in 14 centers in Northeast Japan. We analyzed the usage, efficacy, and safety of ICI therapy (ICIT).

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Objectives: To develop the following three attenuation correction (AC) methods for brain F-fluorodeoxyglucose-positron emission tomography (PET), using deep learning, and to ascertain their precision levels: (i) indirect method; (ii) direct method; and (iii) direct and high-resolution correction (direct+HRC) method.

Methods: We included 53 patients who underwent cranial magnetic resonance imaging (MRI) and computed tomography (CT) and 27 patients who underwent cranial MRI, CT, and PET. After fusion of the magnetic resonance, CT, and PET images, resampling was performed to standardize the field of view and matrix size and prepare the data set.

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Objectives: A simple noninvasive microsphere (SIMS) method using I-IMP and an improved brain uptake ratio (IBUR) method using Tc-ECD for the quantitative measurement of regional cerebral blood flow have been recently reported. The input functions of these methods were determined using the administered dose, which was obtained by analyzing the time activity curve of the pulmonary artery (PA) for SIMS and the ascending aorta (AAo) for the IBUR methods for dynamic chest images. If the PA and AAo regions of interest (ROIs) can be determined using deep convolutional neural networks (DCNN) for segmentation, the accuracy of these ROI-setting methods can be improved through simple analytical operations to ensure repeatability and reproducibility.

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Article Synopsis
  • The study focuses on the efficacy and safety of elranatamab, a bispecific antibody treatment, for Japanese patients with relapsed or refractory multiple myeloma (RRMM).
  • Results showed a 50% objective response rate in one study and 58.3% in another, with no dose-limiting toxicities observed.
  • Although all patients experienced treatment-related adverse events, there were no new safety concerns, suggesting elranatamab is a viable option for RRMM patients in Japan.
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To discharge waste liquid containing radioactive iodine into sewage systems, long-term storage or dilution with a large amount of water may be required until the radioactivity concentration reduces below the standard value. Processing the waste liquid could be easier if radioactive iodine could be separated from the water. This study verified the effectiveness of superabsorbent polymer and α-cyclodextrin as treatment agents to separate radioactive iodine from waste liquids.

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The use of novel agents has improved the outcomes of patients with multiple myeloma. However, almost all patients eventually relapsed, became resistant to available treatments, and, thus, required further therapy. To improve the outcomes of relapsed and/or refractory, the best efficacy in each line of treatment should be achieved.

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A 37-year-old man with refractory classical Hodgkin lymphoma (cHL) underwent PD-1 blockade therapy with nivolumab, which resulted in a partial response. However, treatment was discontinued due to immune-related adverse events (irAEs), including myasthenia gravis and myositis. Retreatment with nivolumab resulted in a complete metabolic response and hepatic irAE.

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This nationwide, multicenter, open-label, single-arm study evaluated the efficacy and safety of the oral proteasome inhibitor (PI), ixazomib plus lenalidomide (LEN) and dexamethasone (DEX) (IRd) following injectable PI-based therapy for relapsed/refractory multiple myeloma (RRMM). Of 45 patients enrolled, 36 patients received IRd after achieving at least a minor response to 3 cycles of bortezomib or carfilzomib plus LEN + DEX (VRd, n=6; KRd, n=30). At median follow-up of 20.

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Alpha-cyclodextrin, a six D-glucose cyclic oligosaccharide, has several applications in food and pharmaceuticals, but has also been reported to retain iodine in a stable manner for 16 months. Radioactive iodine, which may cause thyroid cancer and hypofunction, must be properly managed. If the absorption of radioactive iodine is suppressed, it can be expected to lead to a reduction in thyroid exposure.

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Background/aim: Adult T-cell leukemia (ATL) is a peripheral T-lymphocytic malignancy influenced by human T-cell leukemia virus type 1 (HTLV-1) infection. Aggressive ATL has a poor prognosis, therefore newer agents are desperately needed. We revealed that dimethyl fumarate (DMF) causes ATL cell death via inhibition of nuclear factor-kappa B (NF-B) and signal transducer and activator of transcription 3 signaling.

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We previously showed that cell-surface CD86 expressed on multiple myeloma (MM) cells contributed to not only tumor growth but also antitumor cytotoxic T-lymphocyte responses mediated by induction of IL-10-producing CD4 T cells. The soluble form of CD86 (sCD86) was also detected in serum from patients with MM. Thus, to determine whether sCD86 levels are a useful prognostic factor, we investigated the association of serum sCD86 levels with disease progression and prognosis in 103 newly diagnosed patients with MM.

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Early T-cell precursor (ETP) acute lymphoblastic leukemia/lymphoma (ALL) is generally considered to be a high-risk subtype. We retrospectively analyzed the clinical outcomes of adult patients diagnosed with ETP-ALL or other T-cell ALL (non-ETP T-ALL). The subjects were 82 patients (ETP-ALL: n = 18, non-ETP T-ALL: n = 64) for whom relevant immunophenotype data needed for classification were available.

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Adult T cell leukemia-lymphoma (ATL) is clinically heterogeneous and is classified into four subtypes: acute, lymphoma, chronic, and smoldering. Recently, a new prognostic index based on the value of soluble interleukin-2 receptor, denoted the "iATL-PI," has been proposed for patients with smoldering and chronic ATL. To evaluate the effectiveness of the iATL-PI, we re-analyzed our previously published data on 176 patients with smoldering or chronic ATL (76 smoldering, 100 chronic) diagnosed between 2010 and 2011, as well data from the subsequent follow-up study on prognosis between 2016 and 2017.

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Proton irradiations are highly sensitive to spatial variations, mainly due to their high linear energy transfer (LET) and densely ionizing nature. In realistic clinical applications, the targets of ionizing radiation are inhomogeneous in terms of geometry and chemical composition (i.e.

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Objectives: Somatostatin receptor scintigraphy (SRS) using In-pentetreotide has no established quantification method. The purpose of this study was to develop a new quantitative method to correct the partial volume effect (PVE) for individual energy peaks in In-pentetreotide single-photon emission computed tomography (SPECT).

Methods: Phantom experiments were performed to construct a new quantitative method.

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In the phase 3 IKEMA study (NCT03275285), isatuximab (Isa) plus carfilzomib (K) and dexamethasone (d) significantly improved progression-free survival (PFS) in relapsed multiple myeloma (MM), compared with Kd. This IKEMA subgroup analysis evaluated efficacy and safety of Isa-Kd versus Kd among East Asian patients. Eligible patients had 1-3 prior lines of therapy and were stratified by number of prior lines and revised International Staging System.

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Background/aim: Adult T-cell leukemia (ATL) is a peripheral T lymphocytic malignancy caused by human T-cell leukemia virus type 1 (HTLV-1) infection. Despite treatment that includes novel agents that have been developed, most of ATL patients relapse and acquire multidrug resistance. As a result, the creation of newer agents is critical.

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The Monte Carlo method is employed in this study to simulate the proton irradiation of a water-gel phantom. Positron-emitting radionuclides such as 11C, 15O, and 13N are scored using the Particle and Heavy Ion Transport Code System Monte Carlo code package. Previously, it was reported that as a result of 16O(p,2p2n)13N nuclear reaction, whose threshold energy is relatively low (5.

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We aimed to evaluate the association between the milk consumption and incident stroke in a Japanese population, where milk consumption is lower than that of Western countries. In total, 14,121 participants (4253 men and 9868 women) aged 40-69 years, free from cardiovascular diseases (CVD) were prospectively followed for 10.7 years.

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