Dosimetric data

2018 ◽  
pp. 33-45
Author(s):  
Issam El Naqa ◽  
Randall K. Ten Haken
Keyword(s):  
Dosimetric Data

scholarly journals 455 Proton Beam Therapy in Rectal Cancer: A Systematic Review and Meta-Analysis

2021 ◽  
Vol 108 (Supplement_2) ◽  
Author(s):  
M Fok ◽  
S Toh ◽  
J E Maducolil ◽  
H Fowler ◽  
R Clifford ◽  
...  
Keyword(s):  
Rectal Cancer ◽  
Proton Beam ◽  
Organs At Risk ◽  
Meta Analysis ◽  
Locally Advanced ◽  
Significant Risk ◽  
Proton Beam Therapy ◽  
Recurrent Rectal Cancer ◽  
Pelvic Bone ◽  
Dosimetric Data

Abstract Introduction Radiotherapy for locally advanced rectal cancer is conventionally performed using photon-based radiotherapy (PBR), carrying significant risk of toxicity to organs at risk (OAR). Proton beam therapy (PBT) potentially delivers equivalent dosimetric radiation to the targeted tissue with improved sparing of OAR. We aimed to compare dosimetric irradiation of OAR for PBT versus PBR in patients with rectal cancer and assess any oncological outcomes. Method An extensive electronic literature search was performed from inception till April 2020 and subsequent meta-analysis performed. Results Six articles met the inclusion criteria. Dosimetric data of irradiation delivered to OAR for PBT and PBR were calculated for the same patients. PBT had significantly less irradiated small bowel compared to 3DCRT and IMRT, (MD -16.95, 95% CI [-24.03, -9.88], p < 0.00001) and (MD -6.96, 95% CI [-12.99, -0.94], p = 0.02) respectively. Similar results were observed for bladder and pelvic bone marrow. Two studies reported clinical and oncological results for PBT in recurrent rectal cancer with overall survival reported as 43% and 68%. Conclusions Dosimetric treatment plans have less irradiation of OAR for rectal cancer with PBT compared to PBR. There is a need for further research in PBT and rectal cancer, as promising results have been shown in recurrent rectal cancer.

scholarly journals Hybrid volumetric-modulated arc therapy for postoperative breast cancer including regional lymph nodes: the advantage of dosimetric data and safety of toxicities

2020 ◽  
Vol 61 (5) ◽  
pp. 747-754
Author(s):  
Yoshiko Doi ◽  
Minoru Nakao ◽  
Hideharu Miura ◽  
Shuichi Ozawa ◽  
Masahiro Kenjo ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Lymph Nodes ◽  
Irradiation Dose ◽  
Organs At Risk ◽  
Volumetric Modulated Arc Therapy ◽  
Conformity Index ◽  
Regional Lymph Nodes ◽  
Dosimetric Data ◽  
Arc Therapy

ABSTRACT To improve the homogeneity and conformity of the irradiation dose for postoperative breast cancer including regional lymph nodes, we planned Hybrid volumetric-modulated arc therapy (VMAT), which combines conventional tangential field mainly for the chest area and VMAT mainly for the supraclavicular area and marginal zone. In this study, we compared the dosimetric impact between traditional 3D conformal radiotherapy (3DCRT) and Hybrid VMAT and observed toxicities following Hybrid VMAT. A total of 70 patients indicated between October 2016 and December 2017 were included. The prescribed dose was 50 Gy/25 fractions. For the dosimetric impact, 3DCRT and Hybrid VMAT plans were compared in each patient with respect to the dosimetric parameters. Toxicities were followed using the Common Terminology Criteria for Adverse Events version 4.0. The median follow-up duration was 319 days. For the dosimetric impact, the homogeneity index (HI) and conformity index (CI) of PTV were significantly improved in the Hybrid VMAT plan compared with that in the 3DCRT plan (HI, 0.15 ± 0.07 in Hybrid VMAT vs 0.41 ± 0.19 in 3DCRT, P < 0.001; CI, 1.61 ± 0.44 in Hybrid VMAT vs 2.10 ± 0.56 in 3DCRT, P < 0.001). The mean irradiated ipsilateral lung dose was not significantly different in both plans (12.0 ± 2.4 Gy in Hybrid VMAT vs 11.8 ± 2.8 Gy in 3DCRT, P < 0.533). Regarding toxicity, there were no patients who developed ≥grade 3 acute toxicity and ≥grade 2 pneumonitis during the follow-up. Hybrid VMAT for postoperative breast cancer including regional lymph nodes was a reasonable technique that improved the homogeneity and conformity of the irradiation dose to the planning target volume while keeping the irradiation dose to organs at risk to a minimum.

scholarly journals Dosimetric Characterization of Small Radiotherapy Electron Beams Collimated by Circular Applicators with the New Microsilicon Detector

2022 ◽  
Vol 12 (2) ◽  
pp. 600
Author(s):  
Serenella Russo ◽  
Silvia Bettarini ◽  
Barbara Grilli Leonulli ◽  
Marco Esposito ◽  
Paolo Alpi ◽  
...  
Keyword(s):  
Radiation Therapy ◽  
Electron Beams ◽  
High Energy ◽  
Field Size ◽  
The Novel ◽  
Linear Accelerators ◽  
Depth Dose ◽  
Dosimetric Data ◽  
Output Factors ◽  
Dose Measurements

High-energy small electron beams, generated by linear accelerators, are used for radiotherapy of localized superficial tumours. The aim of the present study is to assess the dosimetric performance under small radiation therapy electron beams of the novel PTW microSilicon detector compared to other available dosimeters. Relative dose measurements of circular fields with 20, 30, 40, and 50 mm aperture diameters were performed for electron beams generated by an Elekta Synergy linac, with energy between 4 and 12 MeV. Percentage depth dose, transverse profiles, and output factors, normalized to the 10 × 10 cm2 reference field, were measured. All dosimetric data were collected in a PTW MP3 motorized water phantom, at SSD of 100 cm, by using the novel PTW microSilicon detector. The PTW diode E and the PTW microDiamond were also used in all beam apertures for benchmarking. Data for the biggest field size were also measured by the PTW Advanced Markus ionization chamber. Measurements performed by the microSilicon are in good agreement with the reference values for all the tubular applicators and beam energies within the stated uncertainties. This confirms the reliability of the microSilicon detector for relative dosimetry of small radiation therapy electron beams collimated by circular applicators.

scholarly journals Cancer Morbidity as Radiation Protection Efficiency Indicator in Urainium Mining Facilities

2017 ◽  
pp. 56-59 ◽  
Author(s):  
T. Pavlenko ◽  
A. Operchuk
Keyword(s):  
Radiation Protection ◽  
Mining Industry ◽  
Surface Mining ◽  
Lung Cancer Mortality ◽  
Radiological Protection ◽  
Protection Efficiency ◽  
The Past ◽  
Dosimetric Data ◽  
The Individual ◽  
Total Effective Dose

The paper reviews the efficience of radiation protection in uranium mining industry. The officially provided data on individual doses for underground and surface mining professionals is analysed and cancer morbity risk is assessed. The researchers defined the individual components of the total effective dose and separately assessed their contributions. The total of 114 cancer cases have been registered during the past 15 years. Accumulated equivalent doses for lungs are estimated from 20 to 430 mSv. The total working time in 56% of individual cancer cases diagnosed made over 20 years. The actual lung cancer mortality rate for miners is established 3 cases per 1000 individuals, which permits to question the authenticity of the dosimetric data and the efficiency of radiological protection applied.

scholarly journals Is it necessary to reduce the radioiodine dose in patients with thyroid cancer and renal failure?

2010 ◽  
Vol 54 (4) ◽  
pp. 413-418 ◽  
Author(s):  
José Willegaignon ◽  
Verena Pinto Brito Ribeiro ◽  
Marcelo Sapienza ◽  
Carla Ono ◽  
Tomoco Watanabe ◽  
...  
Keyword(s):  
Thyroid Cancer ◽  
Dose Adjustment ◽  
Absorbed Dose ◽  
Whole Body ◽  
Half Time ◽  
Dialysis Therapy ◽  
Absorbed Doses ◽  
131I Activity ◽  
Dosimetric Data ◽  
Higher Doses

The objective of this study were to obtain dosimetric data from a patient with thyroid cancer simultaneously undergoing peritoneal dialysis therapy, so as to determine the appropriate amount of 131I activity to be applied therapeutically. Percentages of radioiodine in the blood and the whole-body were evaluated, and radiation absorbed doses were calculated according to OLINDA/EXM software. Whole-body 131I effective half-time was 45.5 hours, being four times longer than for patients without any renal dysfunction. Bone-marrow absorbed dose was 0.074 mGy/MBq, with ablative procedure maintenance at 3.7 GBq, as the reported absorbed dose was insufficiently restrictive to change the usual amount of radioiodine activity administered for ablation. It was concluded that radioiodine therapeutic-dose adjustment, based on individual patient dosimetry, is an important way of controlling therapy. It also permits the safe and potential delivery of higher doses of radiation to tumors and undesirable tissues, with a minimum of malignant effects on healthy tissues.

Sign in / Sign up

Export Citation Format

Share Document