Pub Date : 2020-07-10DOI: 10.18869/ACADPUB.IJRR.18.3.599
Y. Mori, Toshie Mori, K. Adachi, S. Abe, Y. Oshima, A. Takeuchi, Makoto Ito
The treatment results of intensity-modulated stereotactic radiotherapy (IMSRT) by volumetric-modulated arc therapy (VMAT) for intramedullary cervical spinal cord metastases (IMCSCM) in two cases were presented. Case 1: A 76year-old woman showed left-sided motor weakness and left arm pain and dysesthesia due to IMCSCM at C [cervical] 6-7 (located a little to the left laterally) with multiple small brain metastases from thyroid carcinoma. Multiple brain metastases were successfully treated by stereotactic radiosurgery (SRS). In addition, IMCSCM was treated by IM-SRT. Case 2: A 48year-old man presented with asymptomatic IMCSCM at C2 (located a little to the right laterally) after conventional whole brain radiotherapy (WBRT) and multiple sessions of SRS/SRT for multiple brain metastases from lung adenocarcinoma. IMCSCM was treated by IM-SRT. In both cases 39 Gy in 13 fractions (without PTV [planning target volume] margin, D95%=95% dose) was delivered to the IMCSCM (0.3 ml and 0.5 ml in volume respectively) by coplanar 2-full circular arc VMAT. The maximum dose to the tumor was 46.3 Gy in case 1 and 47.1 Gy in case 2. IMCSCM in both cases shrank markedly without adverse effects during the follow-up period of 32 months and 8 months respectively. The symptoms of the extremities in case 1 were subsided completely until the patient’s death at 34 months after SRT from lung metastasis. In case 1 IMCSCM had been thought to be a relatively radioresistant thyroid carcinoma metastasis. In case 2 IMCSCM was near the field of the prior WBRT. However, both tumors were successfully treated without adverse effects by VMAT IM-SRT.
{"title":"Volumetric-modulated arc stereotactic radiotherapy for intramedullary cervical spinal cord metastases: Report of two cases","authors":"Y. Mori, Toshie Mori, K. Adachi, S. Abe, Y. Oshima, A. Takeuchi, Makoto Ito","doi":"10.18869/ACADPUB.IJRR.18.3.599","DOIUrl":"https://doi.org/10.18869/ACADPUB.IJRR.18.3.599","url":null,"abstract":"The treatment results of intensity-modulated stereotactic radiotherapy (IMSRT) by volumetric-modulated arc therapy (VMAT) for intramedullary cervical spinal cord metastases (IMCSCM) in two cases were presented. Case 1: A 76year-old woman showed left-sided motor weakness and left arm pain and dysesthesia due to IMCSCM at C [cervical] 6-7 (located a little to the left laterally) with multiple small brain metastases from thyroid carcinoma. Multiple brain metastases were successfully treated by stereotactic radiosurgery (SRS). In addition, IMCSCM was treated by IM-SRT. Case 2: A 48year-old man presented with asymptomatic IMCSCM at C2 (located a little to the right laterally) after conventional whole brain radiotherapy (WBRT) and multiple sessions of SRS/SRT for multiple brain metastases from lung adenocarcinoma. IMCSCM was treated by IM-SRT. In both cases 39 Gy in 13 fractions (without PTV [planning target volume] margin, D95%=95% dose) was delivered to the IMCSCM (0.3 ml and 0.5 ml in volume respectively) by coplanar 2-full circular arc VMAT. The maximum dose to the tumor was 46.3 Gy in case 1 and 47.1 Gy in case 2. IMCSCM in both cases shrank markedly without adverse effects during the follow-up period of 32 months and 8 months respectively. The symptoms of the extremities in case 1 were subsided completely until the patient’s death at 34 months after SRT from lung metastasis. In case 1 IMCSCM had been thought to be a relatively radioresistant thyroid carcinoma metastasis. In case 2 IMCSCM was near the field of the prior WBRT. However, both tumors were successfully treated without adverse effects by VMAT IM-SRT.","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46611600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-10DOI: 10.18869/ACADPUB.IJRR.18.3.461
Ammar S. Hameed, A. Hashim, E. J. Mohammed
Background: Many people in Iraq and indeed the world choose to drink coffee on a daily basis; accordingly, we planned to find the radium and uranium concentrations in addition to the Radon emission rate to determine if coffee shows the levels of radioactivity that may affect people’s lives. Material and Methods: A nuclear track detector (CR-39) was used to study the natural radioactivity of ten samples of coffee collected from local Iraqi markets. Results: The effective radium content varied from 0.13 to 0.66 Bq/kg with a mean 0.32 Bq/kg. The mass exhalation rates of radon vary from 0.024 – 0.121/kg .h, with a mean 0.059 Bq/kg .h, while the surface exhalation rates of radon vary from 0.47 – 2.39/ .h, with a mean 1.16 Bq/m. h. Uranium content varied from 0.10 to 0.54 ppm with a mean value of 0.26 ppm. Conclusion: Insofar as health effects are concerned, the results have shown that all the samples were entirely safe.
{"title":"The effective radium content and radon concentrations in coffee samples","authors":"Ammar S. Hameed, A. Hashim, E. J. Mohammed","doi":"10.18869/ACADPUB.IJRR.18.3.461","DOIUrl":"https://doi.org/10.18869/ACADPUB.IJRR.18.3.461","url":null,"abstract":"Background: Many people in Iraq and indeed the world choose to drink coffee on a daily basis; accordingly, we planned to find the radium and uranium concentrations in addition to the Radon emission rate to determine if coffee shows the levels of radioactivity that may affect people’s lives. Material and Methods: A nuclear track detector (CR-39) was used to study the natural radioactivity of ten samples of coffee collected from local Iraqi markets. Results: The effective radium content varied from 0.13 to 0.66 Bq/kg with a mean 0.32 Bq/kg. The mass exhalation rates of radon vary from 0.024 – 0.121/kg .h, with a mean 0.059 Bq/kg .h, while the surface exhalation rates of radon vary from 0.47 – 2.39/ .h, with a mean 1.16 Bq/m. h. Uranium content varied from 0.10 to 0.54 ppm with a mean value of 0.26 ppm. Conclusion: Insofar as health effects are concerned, the results have shown that all the samples were entirely safe.","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41793013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-10DOI: 10.18869/ACADPUB.IJRR.18.3.593
S. Kim, E. Han
{"title":"Changes in the radiochemical purity of [18-F]FDG radiopharmaceutical according to the amount of ethanol added","authors":"S. Kim, E. Han","doi":"10.18869/ACADPUB.IJRR.18.3.593","DOIUrl":"https://doi.org/10.18869/ACADPUB.IJRR.18.3.593","url":null,"abstract":"","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42475654","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-10DOI: 10.18869/ACADPUB.IJRR.18.3.531
H. Kaizu, M. Hata, K. Mitsudo, Y. Hayashi, E. Ito, M. Sugiura, S. Takano, Y. Mukai, I. Koike, T. Koizumi
Background: The optimal radiation dose for oral cavity cancers treated with retrograde superselective intra-arterial chemoradiotherapy (SIACRT) is unclear. The aim of the present study was to evaluate the treatment outcome and toxicity in patients treated with <60 Gy compared with those treated with ≥60 Gy to provide evidence for determining the optimal dose. Materials and Methods: Between January 2009 and December 2013, 159 oral cavity cancer patients were treated with SIACRT with curative intent at a single institution. One hundred and twenty-nine patients received ≥60 Gy and 30 received <60 Gy. Local control (LC), disease-free survival (DFS), overall survival (OS), and toxicity were compared. Propensity score matching was performed to reduce bias. Results: The median follow-up period was 48 months (range, 2–88 months). LC (<60 Gy vs. ≥60 Gy, 81.5% vs. 86.1% at 3 years, p = 0.534), DFS (68.8% vs. 72.4% at 3 years, p = 0.816), and OS (85.9% vs. 72.3% at 3 years, p = 0.132) were comparable between the two groups. There was also no difference in toxicity. However, the median overall treatment period was significantly shorter in the <60 Gy cohort (39 days vs. 49 days, p < 0.0001). Conclusion: The radiation dose may be reduced to <60 Gy when treating oral cavity cancers with SIACRT.
{"title":"Oral cavity cancers treated with superselective intra-arterial chemoradiotherapy with radiation doses less than 60 Gy: implications for dose reduction from a propensity score-matched analysis","authors":"H. Kaizu, M. Hata, K. Mitsudo, Y. Hayashi, E. Ito, M. Sugiura, S. Takano, Y. Mukai, I. Koike, T. Koizumi","doi":"10.18869/ACADPUB.IJRR.18.3.531","DOIUrl":"https://doi.org/10.18869/ACADPUB.IJRR.18.3.531","url":null,"abstract":"Background: The optimal radiation dose for oral cavity cancers treated with retrograde superselective intra-arterial chemoradiotherapy (SIACRT) is unclear. The aim of the present study was to evaluate the treatment outcome and toxicity in patients treated with <60 Gy compared with those treated with ≥60 Gy to provide evidence for determining the optimal dose. Materials and Methods: Between January 2009 and December 2013, 159 oral cavity cancer patients were treated with SIACRT with curative intent at a single institution. One hundred and twenty-nine patients received ≥60 Gy and 30 received <60 Gy. Local control (LC), disease-free survival (DFS), overall survival (OS), and toxicity were compared. Propensity score matching was performed to reduce bias. Results: The median follow-up period was 48 months (range, 2–88 months). LC (<60 Gy vs. ≥60 Gy, 81.5% vs. 86.1% at 3 years, p = 0.534), DFS (68.8% vs. 72.4% at 3 years, p = 0.816), and OS (85.9% vs. 72.3% at 3 years, p = 0.132) were comparable between the two groups. There was also no difference in toxicity. However, the median overall treatment period was significantly shorter in the <60 Gy cohort (39 days vs. 49 days, p < 0.0001). Conclusion: The radiation dose may be reduced to <60 Gy when treating oral cavity cancers with SIACRT.","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42566450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-10DOI: 10.18869/ACADPUB.IJRR.18.3.521
M. Chun, Jung In Kim, Dong-Jin Oh, Hong-Gyun Wu, Jung-Bin Park
Background: This study aims to investigate the effect of reference dose calculation grid size (RDCGS) on gamma passing rate (GPR) for patient-specific quality assurance of intensity-modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT). Materials and Methods: A total of 20 patients were retrospectively selected. Both IMRT and VMAT plans were generated for each patient. Reference dose distributions for gamma analysis were calculated with RDCGS of 1–5 mm at intervals of 1 mm. Dose distributions were measured using MapCHECK2 and ArcCHECK dosimeters. Both global and local gamma analyses with gamma criteria of 3%/3 mm, 2%/3 mm, 2%/2 mm, and 2%/1 mm were performed with various RDCGS. Results: As the RDCGS increased from 1 mm to 5 mm, the average global GPRs with 2%/2 mm for VMAT with MapCHECK2 and ArcCHECK decreased by 9.3% and 5.9%, respectively. The average local GPRs decreased by 14% and 11.7%, respectively. For IMRT, the global GPRs decreased by 4.8% and 6%, respectively, whereas the local GPRs decreased by 10.5% and 8.6%, respectively. The effect of the RDCGS on the GPRs became larger when performing local gamma analysis as well as when applying small distance-toagreement (DTA). As the RDCGS increased, the average changes in the GPR per mm of DTA change increased regardless of the type of radiotherapy, detector, or gamma analysis. Conclusion: For an accurate verification of the IMRT and VMAT plans, it is recommended that the reference dose distribution must be calculated with the smallest possible RDCGS.
{"title":"Effect of dose grid resolution on the results of patient-specific quality assurance for intensity-modulated radiation therapy and volumetric modulated arc therapy","authors":"M. Chun, Jung In Kim, Dong-Jin Oh, Hong-Gyun Wu, Jung-Bin Park","doi":"10.18869/ACADPUB.IJRR.18.3.521","DOIUrl":"https://doi.org/10.18869/ACADPUB.IJRR.18.3.521","url":null,"abstract":"Background: This study aims to investigate the effect of reference dose calculation grid size (RDCGS) on gamma passing rate (GPR) for patient-specific quality assurance of intensity-modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT). Materials and Methods: A total of 20 patients were retrospectively selected. Both IMRT and VMAT plans were generated for each patient. Reference dose distributions for gamma analysis were calculated with RDCGS of 1–5 mm at intervals of 1 mm. Dose distributions were measured using MapCHECK2 and ArcCHECK dosimeters. Both global and local gamma analyses with gamma criteria of 3%/3 mm, 2%/3 mm, 2%/2 mm, and 2%/1 mm were performed with various RDCGS. Results: As the RDCGS increased from 1 mm to 5 mm, the average global GPRs with 2%/2 mm for VMAT with MapCHECK2 and ArcCHECK decreased by 9.3% and 5.9%, respectively. The average local GPRs decreased by 14% and 11.7%, respectively. For IMRT, the global GPRs decreased by 4.8% and 6%, respectively, whereas the local GPRs decreased by 10.5% and 8.6%, respectively. The effect of the RDCGS on the GPRs became larger when performing local gamma analysis as well as when applying small distance-toagreement (DTA). As the RDCGS increased, the average changes in the GPR per mm of DTA change increased regardless of the type of radiotherapy, detector, or gamma analysis. Conclusion: For an accurate verification of the IMRT and VMAT plans, it is recommended that the reference dose distribution must be calculated with the smallest possible RDCGS.","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41644343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-10DOI: 10.18869/ACADPUB.IJRR.18.3.505
K. Masood, A. Ullah, A. Hussain, Kh. Mahmood, Gregory R. Hart, W. Muhammad
Background: Dosimetry audits have an important role to safely deliver the prescribed radiation dose to the cancerous area. It not only maintains and improve the treatment standards but also identify issues that are potentially harmful to the patients. This article presents the results of a comparative study of beam output measurements of a high-energy photon beam emitted from a medical linear accelerator. Materials and Methods: The measurements were performed by an International Atomic Energy Commission (IAEA) Quality Assurance/Quality Control survey mission (level-I dosimetry), a national Secondary Standard Dosimetry Laboratory (SSDL) experts (level-II dosimetry) and hospital physicists (level-III dosimetry). Glass dosimeters and cylindrical ionization chambers for level I and cylindrical ionization chambers for level-II and -III dosimetry were used in water by following IAEA TRS-398 protocol. Results: The level-I dosimetry results of glass dosimeters and ionization chambers were compared and percent deviations of -0.4 % and 0.3 % were found for 6 and 15 MV-photon beams, respectively. Similarly, level-II and -III dosimetry results with respect to level-I are in good agreement and within the optimum uncertainty level of ±5%. The annual level-II dosimetry quality audits (i.e., from 2010 to 2015) showed that only one dosimetry audit is out of the optimum level set for this study. However, it is within the tolerance level set for level-II quality audit programs (i.e., < ±5%). Conclusion: In conclusion, this article has demonstrated consistent radiotherapy radiation dosimetry results for MV-photons beams. It also showed quantitative information in-line with the currently achieved accuracy and precision of external megavoltage photon beam dosimetry. Furthermore, this study also established a baseline for current routine audits of radiotherapy dosimetry. Studies of this type are essential to appropriately follow the recommendations and procedures of the pertinent dosimetry protocols.
{"title":"Comparison of level-I, -II and -III dosimetry quality audits for MV-photon beams emitted from medical linear accelerators","authors":"K. Masood, A. Ullah, A. Hussain, Kh. Mahmood, Gregory R. Hart, W. Muhammad","doi":"10.18869/ACADPUB.IJRR.18.3.505","DOIUrl":"https://doi.org/10.18869/ACADPUB.IJRR.18.3.505","url":null,"abstract":"Background: Dosimetry audits have an important role to safely deliver the prescribed radiation dose to the cancerous area. It not only maintains and improve the treatment standards but also identify issues that are potentially harmful to the patients. This article presents the results of a comparative study of beam output measurements of a high-energy photon beam emitted from a medical linear accelerator. Materials and Methods: The measurements were performed by an International Atomic Energy Commission (IAEA) Quality Assurance/Quality Control survey mission (level-I dosimetry), a national Secondary Standard Dosimetry Laboratory (SSDL) experts (level-II dosimetry) and hospital physicists (level-III dosimetry). Glass dosimeters and cylindrical ionization chambers for level I and cylindrical ionization chambers for level-II and -III dosimetry were used in water by following IAEA TRS-398 protocol. Results: The level-I dosimetry results of glass dosimeters and ionization chambers were compared and percent deviations of -0.4 % and 0.3 % were found for 6 and 15 MV-photon beams, respectively. Similarly, level-II and -III dosimetry results with respect to level-I are in good agreement and within the optimum uncertainty level of ±5%. The annual level-II dosimetry quality audits (i.e., from 2010 to 2015) showed that only one dosimetry audit is out of the optimum level set for this study. However, it is within the tolerance level set for level-II quality audit programs (i.e., < ±5%). Conclusion: In conclusion, this article has demonstrated consistent radiotherapy radiation dosimetry results for MV-photons beams. It also showed quantitative information in-line with the currently achieved accuracy and precision of external megavoltage photon beam dosimetry. Furthermore, this study also established a baseline for current routine audits of radiotherapy dosimetry. Studies of this type are essential to appropriately follow the recommendations and procedures of the pertinent dosimetry protocols.","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41676503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-10DOI: 10.18869/ACADPUB.IJRR.18.3.437
M. Manavalan, M. Duraisamy, V. Subramani, H. Godson, G. Krishnan, M. Venkataraman, T. Ganesh
{"title":"Analysis of various dosimetric parameters using multiple detectors in the cyberknife® robotic radiosurgery system","authors":"M. Manavalan, M. Duraisamy, V. Subramani, H. Godson, G. Krishnan, M. Venkataraman, T. Ganesh","doi":"10.18869/ACADPUB.IJRR.18.3.437","DOIUrl":"https://doi.org/10.18869/ACADPUB.IJRR.18.3.437","url":null,"abstract":"","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49018587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-10DOI: 10.18869/ACADPUB.IJRR.18.3.467
Hui Wang, Hongzhuan Chen, Y. Shao, J. Wang, J. Guo, X. Cai, X. Fu, Zhiyong Xu
{"title":"Tumor shrinkage evaluation based interfractional cone beam computed tomography for limited disease small-cell lung cancer and relevant impact on dosimetry","authors":"Hui Wang, Hongzhuan Chen, Y. Shao, J. Wang, J. Guo, X. Cai, X. Fu, Zhiyong Xu","doi":"10.18869/ACADPUB.IJRR.18.3.467","DOIUrl":"https://doi.org/10.18869/ACADPUB.IJRR.18.3.467","url":null,"abstract":"","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48694871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-10DOI: 10.18869/ACADPUB.IJRR.18.3.495
F. Pakniyat, S. Gholami, H. Nedaie, H. Mozdarani, A. Mahmoudzadeh, M. Salimi
Background: The Linear Quadratic (LQ) equation as the most common formula in radiotherapy has a debatable accuracy in modeling high-dose effects. The purpose of this study was to demonstrate bystander response of the Grid treatment in SCC cell line, based on both theoretical calculations and experimental investigations. Materials and methods: The linear quadratic model was used to calculate the equivalent uniform dose (EUD) of a Grid-field with the 10 Gy maximum doses. According to the EUD definition, the identical tumor survival fraction (SF) was expected to obtain from both Grid and openfield single fraction. After observing the difference, the clonogenic and apoptosis assays were exerted to investigate bystander response via medium transfer strategy which was performed from 10Gy-irradiated donors to 1.5Gyirradiated recipients. Results: The EUD was equal to 4 Gy and the SF of 4 Gy EUD and 10 Gy Grid-field were 0.1 ± 0.02 and 0.051 ± 0.008, respectively. These findings contradicted the theoretical expectations of their survivals equality. Moreover, the bystander clonogenic cells death enhanced approximately by 2.91 times (statistically significant); highlighting the bystander response role. The apoptotic findings illustrated that the bystander cells experienced an approximately 10% increase and the apoptotic rate confirmed the clonogenic survival result which was less in the EUD than the Grid-field. Conclusion: Since the SF of the Grid-field was less than the EUD, it revealed the Grid therapeutic advantages plus bystander response manifestation; that was ignored in the LQ equation and may not be demonstrated by sheer theoretical calculations of the modulated-field.
{"title":"Demonstration of bystander response in high dose technique of grid using theoretical calculation by linear quadratic model along with experimental investigations","authors":"F. Pakniyat, S. Gholami, H. Nedaie, H. Mozdarani, A. Mahmoudzadeh, M. Salimi","doi":"10.18869/ACADPUB.IJRR.18.3.495","DOIUrl":"https://doi.org/10.18869/ACADPUB.IJRR.18.3.495","url":null,"abstract":"Background: The Linear Quadratic (LQ) equation as the most common formula in radiotherapy has a debatable accuracy in modeling high-dose effects. The purpose of this study was to demonstrate bystander response of the Grid treatment in SCC cell line, based on both theoretical calculations and experimental investigations. Materials and methods: The linear quadratic model was used to calculate the equivalent uniform dose (EUD) of a Grid-field with the 10 Gy maximum doses. According to the EUD definition, the identical tumor survival fraction (SF) was expected to obtain from both Grid and openfield single fraction. After observing the difference, the clonogenic and apoptosis assays were exerted to investigate bystander response via medium transfer strategy which was performed from 10Gy-irradiated donors to 1.5Gyirradiated recipients. Results: The EUD was equal to 4 Gy and the SF of 4 Gy EUD and 10 Gy Grid-field were 0.1 ± 0.02 and 0.051 ± 0.008, respectively. These findings contradicted the theoretical expectations of their survivals equality. Moreover, the bystander clonogenic cells death enhanced approximately by 2.91 times (statistically significant); highlighting the bystander response role. The apoptotic findings illustrated that the bystander cells experienced an approximately 10% increase and the apoptotic rate confirmed the clonogenic survival result which was less in the EUD than the Grid-field. Conclusion: Since the SF of the Grid-field was less than the EUD, it revealed the Grid therapeutic advantages plus bystander response manifestation; that was ignored in the LQ equation and may not be demonstrated by sheer theoretical calculations of the modulated-field.","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43073525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-10DOI: 10.18869/ACADPUB.IJRR.18.3.539
S. M. Anijdan, Amir Gholami, A. Lahooti
Background: The main aim of this study is to radiolabel dextran coated iron oxide nanoparticles (NPs) (with 80 nm hydrodynamic size) with the Indium-111 and evaluation their biodistribution after intravenous injection normal mice. Materials and Method: The chelator Diethylenetriamine Pentaacetic Acid (DTPA) dianhydride was conjugated to SPION using a small modification of the well-known cyclic anhydride method at a ratio of 1:5 (NPs:DTPA) molar ratio. The reaction was purified with magnetic assorting columns (MACs) using high gradient magnetic field following incubation. Then the radiochemical purity of the radiolabeled NPs were determined using RTLC method. The magnetic properties of nanoparticles were measured by a 1.5 tesla clinical human MRI. Results: The NPs showed high super paramagnetic properties whereas their r2/r1 was 17.6. The RTLC showed that the purity of compound was above 99% after purification and the compound has shown a good in-vitro stability until 6 hours in the presence of human serum. The biodistribution of In-DTPA-NPs in mice demonstrated high uptake in the reticuloendothelial system (RES) and the blood clearance was so fast. Conclusion: Due to magnificent uptakes of this radiotracer in the liver and spleen, its stability and their fast clearance from other tissues, especially in blood, it is suggested that this radiotracer would be suitable for RES theranostics purposes.
{"title":"Development of radiolabeled dextran coated iron oxide nanoparticles with 111-In and its biodistribution studies","authors":"S. M. Anijdan, Amir Gholami, A. Lahooti","doi":"10.18869/ACADPUB.IJRR.18.3.539","DOIUrl":"https://doi.org/10.18869/ACADPUB.IJRR.18.3.539","url":null,"abstract":"Background: The main aim of this study is to radiolabel dextran coated iron oxide nanoparticles (NPs) (with 80 nm hydrodynamic size) with the Indium-111 and evaluation their biodistribution after intravenous injection normal mice. Materials and Method: The chelator Diethylenetriamine Pentaacetic Acid (DTPA) dianhydride was conjugated to SPION using a small modification of the well-known cyclic anhydride method at a ratio of 1:5 (NPs:DTPA) molar ratio. The reaction was purified with magnetic assorting columns (MACs) using high gradient magnetic field following incubation. Then the radiochemical purity of the radiolabeled NPs were determined using RTLC method. The magnetic properties of nanoparticles were measured by a 1.5 tesla clinical human MRI. Results: The NPs showed high super paramagnetic properties whereas their r2/r1 was 17.6. The RTLC showed that the purity of compound was above 99% after purification and the compound has shown a good in-vitro stability until 6 hours in the presence of human serum. The biodistribution of In-DTPA-NPs in mice demonstrated high uptake in the reticuloendothelial system (RES) and the blood clearance was so fast. Conclusion: Due to magnificent uptakes of this radiotracer in the liver and spleen, its stability and their fast clearance from other tissues, especially in blood, it is suggested that this radiotracer would be suitable for RES theranostics purposes.","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45869343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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