Background: Intrahepatic cholangiocarcinoma (ICC) is a challenging primary liver cancer with a poor prognosis, especially in unresectable cases. Traditional palliative irradiation is limited in reducing liver doses. This study aimed to evaluate the efficacy and toxicity of respiratory-gated proton beam therapy without fiducial markers for intrahepatic cholangiocarcinoma.
View Article and Find Full Text PDFPurpose: In concurrent chemoradiotherapy for advanced esophageal cancer, a 2-phase method consisting of initial irradiation of a wide elective nodal region and boost irradiation of the primary lesion is commonly employed. Although dose escalation to the primary lesion may be required to achieve higher local control rates, the radiation dose to critical organs must not exceed dose constraints. To achieve an optimum balance of dose prescription and dose reduction to surrounding organs, such as the lungs and heart, we compared hybrid dose distributions and investigated the best combination of the following recent irradiation techniques: volumetric modulation arc therapy (VMAT), proton broad-beam irradiation, and intensity-modulated proton beam therapy (IMPT).
View Article and Find Full Text PDFAnti-vascular endothelial growth factor (VEGF) therapy is the first-line treatment for diabetic macular edema (DME), but is less effective in some patients. We conducted a prospective study to determine whether laser combination therapy with anti-VEGF was more effective than Ranibizumab monotherapy in anti-VEGF-resistant DME patients. There was no significant difference in the improvement of the best-corrected visual acuity (BCVA) between the laser combination therapy and Ranibizumab monotherapy groups (3.
View Article and Find Full Text PDFBackground: It is important to have precise image guidance throughout proton therapy in order to take advantage of the therapy's physical selectivity.
Purpose: We evaluated the effectiveness of computed tomography (CT)-image guidance in proton therapy for patients with hepatocellular carcinoma (HCC) by assessing daily proton dose distributions. The importance of daily CT image-guided registration and daily proton dose monitoring for tumors and organs at risk (OARs) was investigated.
We evaluated elective nodal irradiation (ENI) doses during radical chemoradiotherapy (CRT) for esophageal cancer (EC). A total of 79 patients (65 men and 14 women) aged 52-80 years with T1-3, N0-3, and M0 (including M1ly) who underwent CRT for EC during November 2012-September 2019 were eligible for this retrospective analysis. Patients were divided into two groups: the high-dose group (HG), including 38 patients who received ≥40 Gy as ENI; and the low-dose group (LG), including 41 patients who received <40 Gy.
View Article and Find Full Text PDFWe 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.
View Article and Find Full Text PDFPurpose: To evaluate the dosimetric advantages of daily adaptive radiotherapy (DART) in intensity-modulated proton therapy (IMPT) for high-risk prostate cancer by comparing estimated doses of the conventional non-adaptive radiotherapy (NART) that irradiates according to an original treatment plan through the entire treatment and the DART that uses an adaptive treatment plan generated by using daily CT images acquired before each treatment.
Methods: Twenty-three patients with prostate cancer were included. A treatment plan with 63 Gy (relative biological effectiveness (RBE)) in 21 fractions was generated using treatment planning computed tomography (CT) images assuming that all patients had high-risk prostate cancer for which the clinical target volume (CTV) needs to include prostate and the seminal vesicle (SV) in our treatment protocol.
Purpose: To evaluate the optimal period of replanning to spare the rectal dose by investigating daily rectal movements during computed tomography (CT) image-guided proton therapy for prostate cancer.
Materials And Methods: To evaluate the optimum reference period for replanning, we analyzed 1483 sets of daily CT (dCT) images acquired from 40 prostate cancer patients and measured the daily rectal movement along the anterior-posterior direction based on the simulator CT (sCT) images and dCT images. We calculated daily dose distributions based on initial plans on the sCT images and replans on the dCT images for 13 representative patients, and evaluated daily dose volume histograms (DVHs) for the prostate, seminal vesicles, and rectum.
The layer-stacking method can provide three-dimensional conformal dose distributions to the target based on a passive scattering method using mini-spread-out Bragg peak (SOBP). The purpose of this work is to demonstrate the effectiveness of a new weight optimization algorithm that can enhance the robustness of dose distributions against layer depth variation in layer-stacking proton beam therapy. In the robustness algorithm, the upper limit of the layer's weight was adapted to the conventional algorithm and varied for 620 weight set evaluations.
View Article and Find Full Text PDFEscherichia coli cells were suspended in phosphate-buffered saline solutions (pH 7.4) at physiological (0.9 %) and hyperosmotic (3.
View Article and Find Full Text PDFVegetative cells of can recover from injury after high-hydrostatic-pressure (HHP) treatment at 250 MPa. DNA microarray analysis revealed that substantial numbers of ribosomal genes and translation-related genes (e.g.
View Article and Find Full Text PDFBackground/aim: To evaluate the utility of endoscopy for assessing radiation esophagitis during chemoradiotherapy (CRT) with proton beam therapy (PBT) boost for esophageal cancer.
Methods: Between December 2012 and December 2016, 38 patients with esophageal cancer were treated with CRT with PBT boost. To evaluate radiation esophagitis, endoscopy was performed after administration of CRT with standard PBT boost (total dose 50-60 Gy relative biological effectiveness [RBE]).
Background: Radiation therapy is an important alternative treatment for advanced cancer. The aim of the current study was to disclose distinct alterations of the biological characteristics of gene expression features in pancreatic cancer cells, MIAPaCa-2, following proton and X-ray irradiation.
Materials And Methods: Using cDNA microarray, we examined the gene expression alterations of MIAPaCa-2 cells following proton or X-ray irradiation.
The authors wish to make the following corrections to this paper [...
View Article and Find Full Text PDFPurpose: 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.
Escherichia coli cells were treated with high hydrostatic pressure (HHP) at 400 and 600 MPa. Metabolites (70-1027 m/z) extracted from HHP-treated cells were analyzed using capillary electrophoresis-time-of-flight mass spectrometry and were compared with those extracted from control cells (not treated with HHP). A total of 133 metabolites were identified and mapped to metabolic pathways, and many of these (42.
View Article and Find Full Text PDFPurpose: 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.
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.
View Article and Find Full Text PDFPurpose: 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.
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).
View Article and Find Full Text PDFPurpose/objective(s): Accurate and reproducible positioning of the breast is difficult due to its deformability and softness; thus, targeting a breast tumor or tumor bed with fractionated radiotherapy using external beam radiation is difficult. The aim of this study was to develop a novel bra to aid in breast immobilization in the prone position.
Materials & Methods: To assess the accuracy of prone position fixation of breast tumors, 33 breast cancer patients with 34 lesions were recruited.
Biosci Biotechnol Biochem
June 2017
High hydrostatic pressure (HHP) affects various cellular processes. Using a sporulation-deficient Bacillus subtilis strain, we characterized the properties of vegetative cells subjected to HHP. When stationary-phase cells were exposed to 250 MPa of HHP for 10 min at 25 °C, approximately 50% of cells were viable, although they exhibited a prolonged growth lag.
View Article and Find Full Text PDFHigh hydrostatic pressure (HHP) process, as a nonthermal process, can be used to inactivate microbes while minimizing chemical reactions in food. In this regard, a HHP level of 100 MPa (986.9 atm/1019.
View Article and Find Full Text PDFEscherichia coli cells were inactivated by high hydrostatic pressure (HHP) at 400-600 MPa and their recovery under various conditions was evaluated by colony counting and flow cytometer (FCM) analyses. The lag time in colony formation and an improved recovery of cells under less oxidative conditions (pyruvate addition to the medium and incubation in anaerobic conditions) were observed for HHP treated cells, which indicated that a significant portion of cells were injured and recovered during incubation after HHP treatment. The lag time for colony formation varied, which suggested a wave of resuscitation and recovered cells may multiply before other injured cells complete resuscitation.
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