Journal of Radiation Research最新文献

{"title":"Development and clinical application of biological dosimetry technology: insights from the HICARE/IAEA 2025 international training course.","authors":"Wanwisa Sudprasert, Oleg Belyakov, Satoshi Tashiro","doi":"10.1093/jrr/rrag003","DOIUrl":"10.1093/jrr/rrag003","url":null,"abstract":"<p><p>The HICARE/IAEA 2025 International Training Course on Biological and Internal Dosimetry, held at Hiroshima University from 10 to 14 February 2025, convened 20 participants from nine countries- Brazil, Indonesia, Japan, Korea, the Philippines, Singapore, Thailand, the United States, and Vietnam-and was jointly organized by the Hiroshima International Council for Health Care of the Radiation-Exposed (HICARE) and the International Atomic Energy Agency (IAEA). With guidance from 13 expert lecturers, the course aimed to enhance global capacity in radiation dose assessment and clinical application of biodosimetry. The program, led by Prof. Satoshi Tashiro (HICARE) and Dr. Oleg Belyakov (IAEA), included lectures on cytogenetic assays, molecular biomarkers, and internal dosimetry using biokinetic modeling and bioassay data. Key themes emphasized the integration of biodosimetry into clinical decision-making, emergency preparedness, and occupational health monitoring. Discussions highlighted the expanding role of biodosimetry in complementing internal dose assessments for patients undergoing diagnostic imaging procedures-such as CT scans and nuclear medicine-as well as for individuals affected by radiological accidents. These sessions underscored the need for harmonized protocols, reliable dose reconstruction methods, and cross-institutional networks to support accurate and timely biodosimetric evaluations in both clinical and emergency settings. The workshop not only had advanced technical competencies but also positioned biodosimetry as a critical tool in global radiological protection strategies. Strong participant engagement and interest in future events reflected the course's impact on strengthening international cooperation and translating research into practice.</p>","PeriodicalId":16922,"journal":{"name":"Journal of Radiation Research","volume":" ","pages":"318-326"},"PeriodicalIF":2.1,"publicationDate":"2026-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13019130/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147284069","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of deliverable dose-mimicking automated volumetric arc radiation therapy planning for stage III non-small cell lung cancer patients: comparison with a commercial DVH-predicted automated planning system.","authors":"Takeru Nakajima, Noriyuki Kadoya, Ryota Tozuka, Masaki Kondo, Shohei Tanaka, Kazuhiro Arai, Yoshiyuki Katsuta, Taichi Hoshino, Takaya Yamamoto, Keiichi Jingu","doi":"10.1093/jrr/rrag001","DOIUrl":"10.1093/jrr/rrag001","url":null,"abstract":"<p><p>This study aimed to evaluate the clinical validity of a dose-mimicking automated planning for volumetric-modulated arc therapy (VMAT) in patients with stage III non-small cell lung cancer (NSCLC), through direct comparison with a commercial dose volume histogram (DVH)-predicted system. We retrospectively analyzed volumetric-modulated arc therapy plans from 75 patients with stage III NSCLC treated at our institution (60 for training, 15 for testing). The dose-mimicking method was implemented using RatoGuide, and the DVH-predicted method was implemented using RapidPlan. The RatoGuide 3D dose-prediction model was trained on the 60 training cases. For each test case, a predicted dose distribution was generated and converted to a deliverable plan (RGDose) in Eclipse using vendor-provided objective functions. A RapidPlan model trained and generated deliverable plans (RPDose) for the same dataset. The clinical plan dose distribution (CliDose) was the reference. We compared dose distributions and DVH parameters among RGDose, RPDose and CliDose. Mean absolute errors (MAEs) relative to CliDose were 0.83 ± 0.66% (targets) and 2.06 ± 3.14% (organs at risk [OARs]) for RGDose, and 0.88 ± 0.66% (targets) and 2.49 ± 3.63% (OARs) for RPDose. There were no significant differences in OAR DVH parameters between RGDose and CliDose. In contrast, compared to CliDose, RPDose showed a significant reduction in the Esophagus D1cc and a significant increase in the Lungs V5Gy. The dose-mimicking method more faithfully reproduced the original clinical plans than the conventional DVH-predicted system, suggesting that dose-mimicking method can capture complex inter-OAR trade-offs and consistently reflect planner intent.</p>","PeriodicalId":16922,"journal":{"name":"Journal of Radiation Research","volume":" ","pages":"248-258"},"PeriodicalIF":2.1,"publicationDate":"2026-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13019132/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146125400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Definitive radiotherapy practices for small-cell lung cancer in Japan: a national survey (JROSG 23-3).","authors":"Nobuki Imano, Noriko Kishi, Shigeo Takahashi, Masaki Nakamura, Yasuhito Hagiwara, Nobuteru Kubo, Takafumi Komiyama, Yoshizumi Kitamoto, Kayoko Tsujino, Masaki Kokubo, Tsuyoshi Takanaka, Takeshi Ebara, Yoshiyuki Shioyama, Keiko Shibuya, Hiroshi Onishi, Kazushige Hayakawa, Yasushi Nagata, Yukinori Matsuo, Tomoki Kimura","doi":"10.1093/jrr/rraf089","DOIUrl":"10.1093/jrr/rraf089","url":null,"abstract":"<p><p>This survey examined the real-world practice of radiotherapy for small-cell lung cancer (SCLC) in Japan, focusing on treatment strategies for limited-disease SCLC (LD-SCLC) and extensive-disease SCLC (ED-SCLC). This study aimed to identify inter-institutional differences, optimize treatment strategies and explore opportunities for standardization. A questionnaire was distributed to members of the Japanese Radiation Oncology Study Group, and responses were collected from 15 December 2023 to 14 March 2024. Responses to 11 questions specifically related to SCLC treatment strategies were analyzed. Among the 112 institutions, 38.3% did not set an upper age limit for concurrent chemoradiotherapy in LD-SCLC, whereas 31.3% set the limit at 80 years. The most commonly used chemotherapy regimen was cisplatin plus etoposide (79.5%), and the predominant radiotherapy fractionation schedule was twice-daily 45 Gy in 30 fractions (97.3%). Elective nodal irradiation (ENI) was ommited in 30.4% of institutions, while 17.9% reported performing ENI in all cases. Intensity-modulated radiation therapy (IMRT) was introduced in 71.4% of institutions, with D50% as the most frequently used dose-prescription method (47.5%). After achieving complete response, 16.1% of institutions routinely perform prophylactic cranial irradiation (PCI) in all patients. Hippocampus-sparing PCI was not widely used at the time of the survey (13.3%). In conclusion, this Japanese nationwide survey highlighted the SCLC treatment patterns and differences compared with non-small lung cancer (NSCLC). ENI omissions and IMRT have become increasingly adopted for SCLC, whereas clinical target volume margin definitions show some variation compared with NSCLC. Regular surveys are essential to monitor the evolution of treatment strategies.</p>","PeriodicalId":16922,"journal":{"name":"Journal of Radiation Research","volume":" ","pages":"228-235"},"PeriodicalIF":2.1,"publicationDate":"2026-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13019133/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146125377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of tumor size on motion tracking and dosimetric accuracy using Radixact Synchrony.","authors":"Ryoto Kaido, Akihiro Takemura, Kakeru Sato, Naoki Kinoshita, Kouhei Sasamoto, Tomohiro Kotsuji, Hiroki Shioura, Toshiki Tateishi, Tetsuya Tsujikawa","doi":"10.1093/jrr/rrag002","DOIUrl":"10.1093/jrr/rrag002","url":null,"abstract":"<p><p>This study aimed to evaluate how planning target volume (PTV) size influences treatment-planning parameters and their relationship to tracking and irradiation accuracy. A high-resolution two-dimensional diode array mounted on a motion phantom was irradiated under four respiratory waveforms using Fiducial Tracking with Respiratory Correlation mode. Spherical PTVs with diameters of 1-4 cm were defined. Treatment-planning parameters, including beam-on time, couch speed, gantry period, kilovoltage imaging interval and modulation factor, were analyzed to assess their relationship with tracking and irradiation accuracy. The root-mean-square error (${delta}_{mathrm{RMS}}$) between tracked and reference target positions, γ pass rate and potential difference as the control parameter of the correlation model were compared across PTV sizes. Correlation and partial correlation analyses were performed to evaluate the relationships between the ${delta}_{text{RMS}}$ and treatment-planning parameters. The ${delta}_{text{RMS}}$ was influenced by the inherent interdependence of beam-on time, gantry period and the kV imaging interval. The kV imaging interval for the PTV of φ1 cm was 4.2 s, longer than those for the other PTV sizes, which made the potential difference unstable during the initial tracking period and kept γ pass rates below 92% across all respiratory waveforms. For the PTVs of φ2-3 cm, potential difference stabilized within ~20 s after beam-on and was associated with an improvement in the γ pass rate. In contrast, for the PTV of φ4 cm, degradation of tracking accuracy was reflected in a reduction in the γ pass rate. Optimizing treatment-planning parameters for each PTV size was essential for precise motion-synchronized irradiation.</p>","PeriodicalId":16922,"journal":{"name":"Journal of Radiation Research","volume":" ","pages":"191-200"},"PeriodicalIF":2.1,"publicationDate":"2026-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13019149/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147276523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"NOP58 modulates radiosensitivity in non-small cell lung cancer via DDX18-mediated DNA damage repair.","authors":"Yiqian Jiang, Weijun Zhang, Yanhong Bao, Fang Su, Bo Wang","doi":"10.1093/jrr/rrag009","DOIUrl":"10.1093/jrr/rrag009","url":null,"abstract":"<p><p>Non-small cell lung cancer (NSCLC) constitutes 80-85% of lung cancers, with advanced cases showing a 20-30% 5-year survival rate. Radiation resistance limits radiotherapy efficacy, and the function of NOP58 in this process is unknown. This study investigated the mechanisms of NOP58 in NSCLC radioresistance. A radiation-resistant NSCLC cell line (H1299R) was established. Bioinformatic analysis of the Cancer Genome Atlas Program data revealed that high NOP58 expression correlates with poor patient prognosis. The expression levels of NOP58 and DDX18 expression were quantified via quantitative real-time polymerase chain reaction and Western blot. Radiosensitivity of H1299R cells and parental H1299 cells was assessed under irradiation (0, 2, 4, 6 and 8 Gy). Cell viability was assessed using cell counting kit-8 and colony formation assays. Apoptosis was detected by flow cytometry with Annexin V/PI staining. DNA damage was analyzed via γ-H2AX immunofluorescence and comet assays. NOP58 knockdown and DDX18 overexpression were performed for rescue experiments, and protein interaction was validated by pull-down assays. NOP58 and DDX18 were significantly upregulated in H1299R cells. H1299R cells exhibited higher cell viability, stronger colony-forming capacity, reduced apoptosis and less DNA damage under irradiation treatment. The depletion of NOP58 in H1299 and H1299R cells exacerbated radiation-induced DNA damage, reduced cell viability and promoted apoptosis, reversing radioresistance. Direct interaction between NOP58 and DDX18 was confirmed by pull-down assay. DDX18 overexpression reversed the radiosensitizing effects of NOP58 knockdown, including attenuated DNA damage and restored cell survival. Overexpression NOP58 converted radiosensitive cells to a resistant phenotype. NOP58 promotes NSCLC radioresistance by interacting with DDX18, regulating its expression and thereby suppressing radiation-induced DNA damage. The NOP58-DDX18 axis could be a promising therapeutic target for improving radiotherapy efficacy in NSCLC.</p>","PeriodicalId":16922,"journal":{"name":"Journal of Radiation Research","volume":" ","pages":"276-292"},"PeriodicalIF":2.1,"publicationDate":"2026-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13019138/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147463548","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of Linear Interpolation System for SMK Model Parameters Evaluated from Cellular-Scale Simulation (LISMEC) and its application to BNCT dosimetry.","authors":"Takafumi Shigehira, Tubasa Watanabe, Minoru Suzuki, Yuho Hirata, Tatsuhiko Ogawa, Atsushi Fujimu, Yoshinori Sakurai, Tatsuhiko Sato","doi":"10.1093/jrr/rraf075","DOIUrl":"10.1093/jrr/rraf075","url":null,"abstract":"<p><p>Boron neutron capture therapy (BNCT) utilizes high linear energy transfer (LET) α-particles and 7Li ions generated through the 10B(n, α)7Li reaction. Precise dosimetry is essential for maximizing therapeutic efficacy while minimizing normal tissue adverse events, considering the microscopic distribution of 10B and cellular structures. Recently, the photon isoeffective dose (DisoE) has been proposed as a more appropriate metric for BNCT treatment planning and can be evaluated using the stochastic microdosimetric kinetic (SMK) model. However, clinical implementation of the SMK model remains challenging due to the difficulty of evaluating its input parameters, which requires computationally intensive radiation transport simulations at the cellular scale. To address this issue, we developed LISMEC (Linear Interpolation System for Stochastic Microdosimetric Kinetic model parameters Evaluated from Cellular-scale simulation), a rapid estimation framework based on precomputed cellular-scale PHITS (Particle and Heavy Ion Transport code System) simulations covering various cell geometries and boron distributions. By applying a linear interpolation algorithm, LISMEC enables the retrieval of SMK model parameters without the need for computationally intensive cellular-scale simulations. The utility of LISMEC, in conjunction with PHITS, was demonstrated through simulations of various irradiation scenarios in reactor-based BNCT. The results showed that DisoE values ranged from 7.4 to 32.7 Gy, even under a fixed macroscopic 10B concentration of 60 ppm. These findings emphasize the importance of incorporating a microscopic distribution of 10B and cellular structures into BNCT treatment planning.</p>","PeriodicalId":16922,"journal":{"name":"Journal of Radiation Research","volume":" ","pages":"170-181"},"PeriodicalIF":2.1,"publicationDate":"2026-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13019147/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146125382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Predictors of acute genitourinary toxicity in real-time image-gated spot-scanning proton beam therapy for prostate cancer.","authors":"Sho Seri, Norihiro Aibe, Takuya Kimoto, Toshiyuki Ogata, Kanako Kawabata, Koji Masui, Shinsuke Nagasawa, Yuki Yoshino, Sho Watanabe, Akito Asato, Shoko Hirano, Satoshi Ikeda, Takumi Shiraishi, Atsuko Fujihara, Hideya Yamazaki, Osamu Ukimura, Kei Yamada, Gen Suzuki","doi":"10.1093/jrr/rrag012","DOIUrl":"10.1093/jrr/rrag012","url":null,"abstract":"<p><p>Proton beam therapy (PBT) provides sharper dose gradients than conventional photon radiotherapy, potentially reducing radiation exposure to normal tissues. However, acute genitourinary adverse events (GU AEs) remain a clinical concern. This study aimed to evaluate the incidence and predictors of grade ≥ 2 acute GU AEs in patients with localized prostate cancer treated with real-time image-gated, spot-scanning PBT (RGPT). We analyzed the prospective study data of 326 patients who received RGPT at a dose of 63 Gy (relative biological effectiveness [RBE]) in 21 fractions between 2019 and 2021. Acute GU AEs were graded according to the Common Terminology Criteria for Adverse Events (version 5.0). Multivariable logistic regression was used to analyze potential predictive factors, including baseline International Prostate Symptom Score (IPSS), age, comorbidities, hydrogel spacer placement, use of anticoagulants or urinary symptom medications, clinical stage, National Comprehensive Cancer Network (NCCN) risk classification, prostate volume, and dose-volume histogram parameters. Grade 2 acute GU AEs occurred in 127 patients (39.0%), whereas no grade ≥ 3 events were observed. Moderate (odds ratio [OR] = 1.71; 95% confidence interval [CI]: 1.03-2.82) and severe (OR = 3.75; 95% CI: 1.49-9.46) baseline IPSS, as well as age ≥ 75 years (OR = 1.80; 95% CI: 1.10-2.95), were significant independent predictors of grade ≥ 2 GU AEs. No dose-volume histogram parameters were significantly associated with grade ≥ 2 GU AEs. Baseline urinary symptoms and older age were independent predictors of grade ≥ 2 GU AEs, emphasizing the importance of pretreatment evaluation in optimizing patient selection and management.</p>","PeriodicalId":16922,"journal":{"name":"Journal of Radiation Research","volume":" ","pages":"293-302"},"PeriodicalIF":2.1,"publicationDate":"2026-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13019134/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147463576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dosimetric comparison of scanned proton therapy and volumetric modulated arc therapy in isodose-prescribed stereotactic body radiotherapy for lung cancer.","authors":"Yuki Tominaga, Hiromitsu Endo, Takahiro Kato, Yushi Wakisaka, Tatsuyuki Higashikawa, Masao Murakami, Michinori Yamamoto","doi":"10.1093/jrr/rraf091","DOIUrl":"10.1093/jrr/rraf091","url":null,"abstract":"<p><p>This study evaluated the feasibility of pencil beam scanning (PBS) proton therapy for stereotactic body radiotherapy using an isodose prescription in patients with isolated early-stage lung cancer, comparing dose-volume metrics with those of volumetric modulated arc therapy (VMAT). Treatment plans were generated for 10 patients with tumors located at least 2 cm from the trachea. Each plan prescribed 48 Gy(RBE) in four fractions with a 60% isodose prescription. Both multi-field optimized and single-field optimized PBS plans used four fields, while VMAT plans used two coplanar arcs. Plan robustness was assessed by simulating setup errors of ±5.0 mm and density uncertainties of ±3.5%, with worst-case target coverage also analyzed. Comparisons among the three planning strategies employed Bonferroni-adjusted multiple comparisons for target coverage, robustness, and organ-at-risk doses. PBS achieved target coverage comparable to VMAT, with similar D98% (63.2 ± 1.3 GyRBE vs. 64.0 ± 1.6 Gy; P = 0.12), mean doses (73.2 ± 0.8 GyRBE vs. 73.7 ± 1.2 Gy; P = 0.21), and robustness (D98%: 50.2 ± 0.9 GyRBE vs. 50.3 ± 1.1 Gy; P = 0.77). For the normal lung, PBS significantly reduced low-dose exposure up to V10Gy, whereas VMAT was more effective in reducing doses from V20Gy to the prescription level. All evaluated organ-at-risks received significantly lower mean doses with PBS than with VMAT (P < 0.05). Under a 60% isodose prescription for lung stereotactic body radiotherapy, multi-field optimized-based PBS proton therapy provides target coverage and robustness comparable to VMAT while offering superior normal tissue sparing.</p>","PeriodicalId":16922,"journal":{"name":"Journal of Radiation Research","volume":" ","pages":"236-247"},"PeriodicalIF":2.1,"publicationDate":"2026-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13019148/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146125395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Willingness to engage in nuclear or radiological emergency response among medical personnel at four university hospitals in Kyushu, Japan.","authors":"Arkhat Omarbek, Keita Iyama, Takanobu Otaguro, Goro Tajima, Kazunori Yamashita, Osamu Tasaki","doi":"10.1093/jrr/rraf092","DOIUrl":"10.1093/jrr/rraf092","url":null,"abstract":"<p><p>Following the Fukushima Daiichi Nuclear Power Plant accident, Japan enhanced its nuclear disaster preparedness framework. However, personnel shortages stemming from fear and anxiety persist as a critical issue during such disasters. This study investigated the willingness of medical professionals at four university hospitals in Kyushu to participate in nuclear disaster response activities and explored factors influencing this willingness. A cross-sectional web-based survey was conducted among staff at Nagasaki, Kyushu, Saga and Kagoshima University Hospitals. Participants answered 19 questions assessing their willingness to participate in nuclear or radiological emergency response and associated psychosocial and occupational factors. Multiple regression analysis was used to identify predictors of willingness (Q1). A total of 378 valid responses were analyzed. Demographic variables, including age, sex, occupation and disaster experience, did not significantly influence willingness. However, interest in nuclear or radiological emergencies (β =0.383, P < 0.05), Incentives (β =0.249), Family understanding (β =0.116) and Occupational norms (β =0.114) were positively associated with willingness. Conversely, Anxiety (β = -0.151), Expectation of routine training (β = -0.138) and Perceived frequency of nuclear disasters (β = -0.104) were negatively associated with willingness. Medical staff's willingness to respond to nuclear or radiological emergencies is influenced more by psychological and occupational perceptions than by demographic factors. Interventions such as incentive programs, family support initiatives, targeted training and anxiety-reduction strategies may enhance preparedness for and participation in future nuclear or radiological emergencies.</p>","PeriodicalId":16922,"journal":{"name":"Journal of Radiation Research","volume":" ","pages":"182-190"},"PeriodicalIF":2.1,"publicationDate":"2026-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13019142/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146132193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geographic access to radiotherapy facilities in Japan.","authors":"Yuhei Koike, Satoaki Nakamura, Hodaka Numasaki, Noboru Tanigawa","doi":"10.1093/jrr/rrag004","DOIUrl":"10.1093/jrr/rrag004","url":null,"abstract":"<p><p>Daily attendance requirements for radiotherapy (RT) make geographic accessibility a critical determinant of treatment adherence and completion. Although facility surveys indicate that advanced modalities such as intensity-modulated radiotherapy (IMRT) and brachytherapy are concentrated in urban centers, precise nationwide quantification of the resulting patient travel burden remains lacking. This study provides the first nationwide, modality-stratified assessment of geographic access to RT in Japan. Using the Open Source Routing Machine and a high-resolution dataset of 176 964 household-weighted 1-km mesh centroids, we calculated driving times to the nearest external-beam radiotherapy (EBRT), IMRT and brachytherapy facilities. Beyond standard distribution metrics, we generated high-resolution 'penalty maps' to quantify the incremental time tax imposed by advanced modality requirements. Although EBRT access was uniformly short nationwide, with a median travel time of 6.48 min, this increased to 8.26 min for IMRT and 14.06 min for brachytherapy. Crucially, the proportion of the population facing poor access (≥120 min) doubled from 0.24% for EBRT to 0.48% for brachytherapy. The spatial analysis identified specific 'newly poor-access' areas-regions that are accessible for EBRT but become remote when advanced care is needed-forming coherent geographic clusters in mountainous and island zones. These findings demonstrate that modality requirements introduce meaningful inequities despite strong national EBRT infrastructure. These indicators provide a vital evidence base for spatially optimizing resources to mitigate travel burdens for Japan's aging, mobility-limited population.</p>","PeriodicalId":16922,"journal":{"name":"Journal of Radiation Research","volume":" ","pages":"259-265"},"PeriodicalIF":2.1,"publicationDate":"2026-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13019145/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147290283","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}