{"title":"Comparison of single- and multi-isocenter planning with Dynamic WaveArc for multiple brain metastases.","authors":"Mitsuaki Terabe, Takeshi Kamomae, Yuki Taniguchi, Hajime Ichikawa, Takehiro Yamada, Takayuki Miyachi, Risei Miyauchi, Junji Ito, Shunichi Ishihara","doi":"10.1093/jrr/rrae098","DOIUrl":"https://doi.org/10.1093/jrr/rrae098","url":null,"abstract":"<p><p>Dynamic WaveArc (DWA) is a technique used for continuous, non-coplanar volumetric-modulated arc therapy on the Vero4DRT platform. This study aimed to evaluate the application of single-isocenter DWA (SI-DWA) for treating multiple brain metastases by comparing dose distribution and irradiation time with multi-isocenter DWA (MI-DWA) through retrospective treatment planning. Treatment plans were developed for SI-DWA and MI-DWA in 14 cases with 3-5 brain metastases. Parameters assessed included target dose indices, such as conformity index (CI) of the planning target volume (PTV), volumes of normal brain excluding gross tumor volumes (GTVs) receiving a single dose equivalent of 14 Gy (V14), V30%, V20%, V10%, volumes of normal brain, including GTVs receiving a single dose equivalent of 12 Gy (V12), D2% for other organs at risk, and beam-on time. SI-DWA showed inferior CI, V14, and V12 values for lesions with PTV volumes <1 cc, whereas it performed equivalently to MI-DWA for lesions with PTV volumes ≥1 cc. SI-DWA resulted in higher volumes of normal brain receiving low doses compared to MI-DWA. SI-DWA exhibited significantly shorter beam-on times than MI-DWA. In conclusion, SI-DWA is an effective method for treating multiple brain metastases with PTV volumes ≥1 cc, offering an index of radiation-induced brain necrosis comparable with MI-DWA while allowing for shorter irradiation times.</p>","PeriodicalId":16922,"journal":{"name":"Journal of Radiation Research","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142895561","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Quantification of beam size impact on intensity-modulated proton therapy with robust optimization in head and neck cancer-comparison with intensity-modulated radiation therapy.","authors":"Hiromi Baba, Kenji Hotta, Ryo Takahashi, Kana Motegi, Yuya Sugama, Takeji Sakae, Hidenobu Tachibana","doi":"10.1093/jrr/rrae097","DOIUrl":"https://doi.org/10.1093/jrr/rrae097","url":null,"abstract":"<p><p>We assessed the effect of beam size on plan robustness for intensity-modulated proton therapy (IMPT) of head and neck cancer (HNC) and compared the plan quality including robustness with that of intensity-modulated radiation therapy (IMRT). IMPT plans were generated for six HNC patients using six beam sizes (air-sigma 3-17 mm at isocenter for a 70-230 MeV) and two optimization methods for planning target volume-based non-robust optimization (NRO) and clinical target volume (CTV)-based robust optimization (RO). Worst-case dosimetric parameters and plan robustness for CTV and organs-at-risk (OARs) were assessed under different scenarios, assuming a ± 1-5 mm setup error and a ± 3% range error. Statistical comparisons of NRO-IMPT, RO-IMPT and IMRT plans were performed. In regard to CTV-D99%, RO-IMPT with smaller beam size was more robust than RO-IMPT with larger beam sizes, whereas NRO-IMPT showed the opposite (P < 0.05). There was no significant difference in the robustness of the CTV-D99% and CTV-D95% between RO-IMPT and IMRT. The worst-case CTV coverage of IMRT (±5 mm/3%) for all patients was 96.0% ± 1.4% (D99%) and 97.9% ± 0.3% (D95%). For four out of six patients, the worst-case CTV-D95% for RO-IMPT (±1-5 mm/3%) were higher than those for IMRT. Compared with IMRT, RO-IMPT with smaller beam sizes achieved lower worst-case doses to OARs. In HNC treatment, utilizing smaller beam sizes in RO-IMPT improves plan robustness compared to larger beam sizes, achieving comparable target robustness and lower worst-case OARs doses compared to IMRT.</p>","PeriodicalId":16922,"journal":{"name":"Journal of Radiation Research","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142895562","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Utilization and regional disparities of radiotherapy in cancer treatment in Japan: a longitudinal study using NDB open data.","authors":"Kazuya Takeda, Rei Umezawa, Takaya Yamamoto, Noriyoshi Takahashi, Hiroshi Onishi, Keiichi Jingu","doi":"10.1093/jrr/rrae100","DOIUrl":"https://doi.org/10.1093/jrr/rrae100","url":null,"abstract":"<p><p>The National Database of Health Insurance Claims and Specific Health Checkups of Japan (NDB) is a database that stores anonymized information on medical receipts and health checkups in Japan. The NDB Open Data is a publicly accessible summary table of the NDB database. To reveal annual trends and regional disparities in radiotherapy utilization in Japan, we analyzed the NDB Open Data tables for a 9-year period from 2014 to 2022. We extracted medical cost codes for radiotherapy management fees and specific types of radiotherapy, such as stereotactic irradiation (STI) and intensity-modulated radiotherapy (IMRT), to analyze nationwide changes over time. To investigate regional disparities, we counted the three subitems representing 3-dimensional conformal radiotherapy (3D-CRT), IMRT, and STI for each prefecture per year. The utilization of advanced radiotherapy techniques, such as IMRT (199% increase), increased, while the use of simpler forms of irradiation, such as 1 or 2-opposite fields irradiation (40% decrease), decreased in the period from 2014 to 2022. Regarding regional disparities, the coefficients of variation in 47 prefectures for 3D-CRT remained relatively stable at 0.17 in 2014 and 0.18 in 2022, while the coefficients of variation for IMRT and STI decreased from 0.64 and 0.39 in 2014 to 0.31 and 0.36 in 2022, respectively. The popularization of IMRT was correlated with the number of certified radiation oncologists in the prefecture. In conclusion, although the utilization of high-precision radiotherapy in Japan has been increasing and regional differences have been diminishing, there are still persistent disparities.</p>","PeriodicalId":16922,"journal":{"name":"Journal of Radiation Research","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142895564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Ultra-high dose rate (FLASH) carbon ion irradiation inhibited immune suppressive protein expression on Pan02 cell line.","authors":"Shohei Katsuki, Kazumasa Minami, Karin Oniwa, Masashi Yagi, Shinichi Shimizu, Noriaki Hamatani, Masaaki Takashina, Tatsuaki Kanai, Kazuhiko Ogawa","doi":"10.1093/jrr/rrae091","DOIUrl":"https://doi.org/10.1093/jrr/rrae091","url":null,"abstract":"<p><p>Recently, ultra-high dose rate (> 40 Gy/s, uHDR; FLASH) radiation therapy (RT) has attracted interest, because the FLASH effect that is, while a cell-killing effect on cancer cells remains, the damage to normal tissue could be spared has been reported. This study aimed to compare the immune-related protein expression on cancer cells after γ-ray, conventionally used dose rate (Conv) carbon ion (C-ion), and uHDR C-ion. B16F10 murine melanoma and Pan02 murine pancreas cancer were irradiated with γ-ray at Osaka University and with C-ion at Osaka HIMAK. The dose rates at 1.16 Gy/s for Conv and 380 Gy/s for uHDR irradiation. The expressed calreticulin (CRT), major histocompatibility complex class (MHC)-I, and programmed cell death 1 ligand (PD-L1) were evaluated by flow cytometry. Western blotting and PCR were utilized to evaluate endoplasmic reticulum (ER) stress, DNA damage, and its repair pathway. CRT, MHC-I on B16F10 was also increased by irradiation, while only C-ion increased MHC-I on Pan02. Notably, PD-L1 on B16F10 was increased after irradiation with both γ-ray and C-ion, while uHDR C-ion suppressed the expression of PD-L1 on Pan02. The present study indicated that uHDR C-ion has a different impact on the repair pathway of DNA damage and ER than the Conv C-ion. This is the first study to show the immune-related protein expressions on cancer cells after uHDR C-ion irradiation.</p>","PeriodicalId":16922,"journal":{"name":"Journal of Radiation Research","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142895563","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Features of internal absorbed dose microdistribution in biological tissue irradiated by 31SiO2 microparticles compared with dose microdistribution from exposure to 56MnO2 particles.","authors":"Valeriy Stepanenko, Andrey Kaprin, Sergey Ivanov, Peter Shegay, Viktoria Bogacheva, Sergey Shinkarev, Hitoshi Sato, Noriyuki Kawano, Megu Ohtaki, Nariaki Fujimoto, Satoru Endo, Aya Sakaguchi, Evgenia Ostroumova, Kassym Zhumadilov, Almagul Kushugulova, Masaharu Hoshi","doi":"10.1093/jrr/rrae096","DOIUrl":"https://doi.org/10.1093/jrr/rrae096","url":null,"abstract":"<p><p>Radiobiological studies are ongoing to understand the consequences of internal exposure to neutron-activated radioactive microparticles, which were sprayed over experimental rats and mice. Special attention in these experiments is given to internal irradiation with radioactive microparticles with short-lived neutron-activated radionuclides 31Si (T1/2 = 2.62 h) and 56Mn (T1/2 = 2.58 h), which are among the main dose-forming factors from residual radioactivity activated in soils by neutrons in the first hours after atmospheric nuclear explosions. The presented work is devoted to microdosimetry peculiarities of 31SiO2 and 56MnO2 microparticles. The radiation from 31Si consists of intensive short-range beta particles and gamma rays with very low intensity. It differs from the radiation of 56Mn, which includes intensive beta particles, low energy Auger electrons and very intensive gamma rays. Differences in the energies and intensities of short-range beta particles and penetrating gamma rays emitted by 31SiO2 and 56MnO2 microparticles can lead to differences in the spatial microdistribution of absorbed dose around the corresponding radioactive microparticles embedded in biological tissue. It was found in the presented work that the absorbed doses of beta radiation emitted by 56MnO2 and 31SiO2 microparticles has significant but different spatial gradients with distances in biological tissue that correspond to the typical thickness of epithelial cells of lungs' alveoli and bronchioles. The results obtained are necessary for a better understanding of radiobiological effects of internal exposure by radioactive microparticles with 56Mn and 31Si observed in framework of performed and ongoing radiobiological studies with experimental animals-rats and mice.</p>","PeriodicalId":16922,"journal":{"name":"Journal of Radiation Research","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142854555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"DNA double-strand break repair capacity and normal tissue toxicity induced by radiotherapy.","authors":"Ikuno Nishibuchi, Satoshi Tashiro","doi":"10.1093/jrr/rrae081","DOIUrl":"10.1093/jrr/rrae081","url":null,"abstract":"<p><p>Radiation therapy is used in the treatment of various cancers, and advancements in irradiation techniques have further expanded its applicability. For radiation oncologists, predicting adverse events remains a critical challenge, even with these technological advancements. Although numerous studies have been conducted to predict individual radiosensitivity, no biomarkers have been clinically applied thus far. This review focuses on γ-H2AX foci and chromosomal aberrations, providing an overview of their association with normal tissue toxicities.</p>","PeriodicalId":16922,"journal":{"name":"Journal of Radiation Research","volume":"65 Supplement_1","pages":"i52-i56"},"PeriodicalIF":1.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11647926/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142829112","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":"Segmentation of the general public according to differences in knowledge and beliefs about radiation-cluster analysis by attitude, knowledge, belief and anxiety.","authors":"Kei Hirai, Asayo Yamamura, Yuko Matsumura, Asako Miura, Ekou Yagi, Ryohei Fujino, Masaharu Tsubokura, Fumio Ohtaka","doi":"10.1093/jrr/rrae030","DOIUrl":"10.1093/jrr/rrae030","url":null,"abstract":"<p><p>Following the 2011 Fukushima Daiichi Nuclear Power Plant accident, public behaviors have been marked by excessive avoidance and stigma, driven by fear and uncertainty regarding radiation exposure and its health implications. Despite extensive media dissemination of information on radiation, the precise nature of the public's knowledge, beliefs and the resultant behavioral responses remain unclear. This study aimed to segment the population based on their attitudes, knowledge, beliefs and anxiety levels about radiation, correlating these factors with their cognitive and behavioral responses to radiation exposure. Surveying 2400 individuals, we identified seven distinct segments that illustrated a spectrum of health concerns, even among those well-informed about radiation. Notably, individuals with higher health anxiety were found to reject discriminatory prejudices linked to radiation, yet they tended to distrust official information, potentially as a psychological mechanism to justify their avoidance behaviors. These findings underscore the need for tailored communication strategies that address the complex landscape of radiation-related perceptions and misinformation.</p>","PeriodicalId":16922,"journal":{"name":"Journal of Radiation Research","volume":"65 Supplement_1","pages":"i42-i51"},"PeriodicalIF":1.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11647920/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142829141","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":"Use of optical techniques to evaluate the ionizing radiation effects on biological specimens.","authors":"Hideaki Fujita, Tomonobu M Watanabe","doi":"10.1093/jrr/rrae016","DOIUrl":"10.1093/jrr/rrae016","url":null,"abstract":"<p><p>Radiation induces various changes in biological specimens; however, the evaluation of these changes is usually complicated and can be achieved only through investment in time and labor. Optical methods reduce the cost of such evaluations as they require less pretreatment of the sample, are adaptable to high-throughput screening and are easy to automate. Optical methods are also advantageous, owing to their real-time and onsite evaluation capabilities. Here, we discuss three optical technologies to evaluate the effects of radiation on biological samples: single-molecule tracking microscopy to evaluate the changes in the physical properties of DNA, Raman spectral microscopy for dosimetry using human hair and second-harmonic generation microscopy to evaluate the effect of radiation on the differentiation of stem cells. These technologies can also be combined for more detailed information and are applicable to other biological samples. Although optical methods are not commonly used to evaluate the effects of radiation, advances in this technology may facilitate the easy and rapid assessment of radiation effects on biological samples.</p>","PeriodicalId":16922,"journal":{"name":"Journal of Radiation Research","volume":"65 Supplement_1","pages":"i117-i125"},"PeriodicalIF":1.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11647921/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142829145","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":"Population shifts during the reconstruction period in areas marked as evacuation zones after the Fukushima Daiichi nuclear power plant accident: a mobile spatial statistics data-based time-series clustering analysis.","authors":"Toshiki Abe, Hiroki Yoshimura, Hiroaki Saito, Michio Murakami, Asaka Higuchi, Nobuaki Moriyama, Isamu Amir, Naomi Ito, Akihiko Ozaki, Toyoaki Sawano, Chika Yamamoto, Tianchen Zhao, Masaharu Tsubokura","doi":"10.1093/jrr/rrae024","DOIUrl":"10.1093/jrr/rrae024","url":null,"abstract":"<p><p>An accurate understanding of the population is essential for the development of medical care and social resources. However, the development of transportation networks has increased temporal and spatial fluctuations in the population, making it difficult to accurately forecast medical care demand, especially during disaster recovery. This study examined the population movement in areas affected by the Fukushima Daiichi nuclear power plant accident using demographic data. The target area includes two cities, seven towns, and three villages that are in the evacuation zone. Using a population estimation that reflects changes in population by time of day, which was obtained from a mobile phone company (NTT DOCOMO), we applied clustering analysis to examine the population dynamics over a 4-year period. From 2019 to 2022, the population increased in eight areas and decreased in four areas. The population was further classified into five groups, identifying the unique characteristics and fluctuations of each group. Different regions had different percentages of groups reflecting the characteristics of their populations. The differences among the regions and demographic transition showed the potential to understand the challenges of recovery and to use the data to inform healthcare planning and social policies. This method, which utilizes estimated population data, is also applicable to the study of medical resources and social policies in the event of future disasters and may be useful in analyzing regional characteristics in detail.</p>","PeriodicalId":16922,"journal":{"name":"Journal of Radiation Research","volume":"65 Supplement_1","pages":"i106-i116"},"PeriodicalIF":1.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11647923/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142829124","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":"Role of radiation emergency medicine: historical view-a perspective on the past, present, and future.","authors":"Makoto Akashi","doi":"10.1093/jrr/rrae037","DOIUrl":"10.1093/jrr/rrae037","url":null,"abstract":"<p><p>The more science progresses, the more life and society change. Medicine also changes with the times and the culture. This is also true for radiation emergency medicine, which includes dose-assessment leading to diagnosis, treatment, medical follow-up and prognosis of persons who have developed acute injury or illness due to radioactive contamination or radiation exposure. Before the report of X-rays by Roentgen, there was evidence that X-rays had been emitted from the electrically excited Crookes tube and that skin injury had been caused by the X-rays. Thus, the history of radiation and its exposure started before Roentgen. During the early stage of radiation use, people were simply exposed to radiation but were unaware of any danger. Radioactive materials were found soon after Roentgen's report, and contamination with these materials occurred. Together with the development of science and technology, sophisticated radiation devices were produced, and the use and application of radiation became much enhanced. New radionuclides were found one after another, leading to identification of different qualities of radiation. Development of nuclear physics allowed people to artificially produce radionuclides and to construct a nuclear reactor. After World War II, nuclear power plants were constructed, and related facilities such as nuclear fuel processing, reprocessing and spent fuel storage facilities were built. If radiation accidents or events occur at such facilities, radiation exposure with thermal or chemical burns could occur. Together with the expansion of globalism in the world and division in the society, there are now increasing concerns regarding the malicious usage of radiation by radiological dispersal devices (RDDs) including a dirty bomb. Upon detonation of RDDs, blast and thermal injuries with radiation exposure could be caused. In the present society, the natures of exposure to radiation and contamination with radioactive materials have become much more complicated. Not even mentioning the atomic bomb, the detonation of RDDs also necessitates scenarios of medical responses to complicated injuries and the involvement of numbers of people. This article looks back at the history of radiation and addresses the medical responses to radiation injuries that change with the times.</p>","PeriodicalId":16922,"journal":{"name":"Journal of Radiation Research","volume":"65 Supplement_1","pages":"i24-i31"},"PeriodicalIF":1.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11647935/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142829128","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}