scholarly journals A dummy-run evaluation of postoperative hypofractionated intensity-modulated radiation therapy (POHIM-RT) trials for cervical cancer

2020 ◽  
Vol 62 (1) ◽  
pp. 149-154
Author(s):  
Won Kyung Cho ◽  
Heejung Kim ◽  
Won Park ◽  
Sang-Won Kim ◽  
Jongwon Kim ◽  
...  
Keyword(s):  
Cervical Cancer ◽  
Quality Assurance ◽  
Radiation Therapy ◽  
Organs At Risk ◽  
Treatment Plan ◽  
Intensity Modulated Radiation Therapy ◽  
Target Volume ◽  
Similarity Coefficients ◽  
Intensity Modulated ◽  
And Performance

Abstract The postoperative hypofractionated intensity-modulated radiation therapy (POHIM-RT) trial is a phase II study to evaluate toxicity following hypofractionated intensity modulated radiation therapy (IMRT) for cervical cancer. This study describes the results of a benchmark procedure for RT quality assurance of the POHIM-RT trial. Six participating institutions were provided computed tomography for RT planning and an IMRT plan for a sample and were instructed to delineate volumes, create a treatment plan and quality assurance (QA) plan, and submit the results of all procedures. The inter-institutional agreements on RT volume and plan results were evaluated using the kappa value and dice similarity coefficients. The simultaneous truth and performance level estimation (STAPLE) method was employed to generate a consensus target volume. The treatment volumes, organs-at-risk volumes, and results of the RT plan and QA reported by the institutions were acceptable and adhered well to the protocol. In terms of clinical target volume (CTV) delineation, there were differences between the institutions, particularly in vaginal cuff and paracolpium subsites. Consensus CTV was generated from the collected CTVs with the STAPLE method. The participating institutions showed considerable agreement regarding volume, dose and QA results. To improve CTV agreement in CTV, we provided feedback with images of the consensus target volume and detailed written guidelines for specific subsites that were the most heterogeneous.

scholarly journals Dosimetric comparison between 3D conformal and intensity-modulated radiation therapy for prostate cancer

2010 ◽  
Vol 9 (2) ◽  
pp. 77-85 ◽  
Author(s):  
Courtney Buckey ◽  
Gregory Swanson ◽  
Sotirios Stathakis ◽  
Nikos Papanikolaou
Keyword(s):  
Radiation Therapy ◽  
Organs At Risk ◽  
External Beam Radiotherapy ◽  
Radiation Therapy Oncology Group ◽  
Intensity Modulated Radiation Therapy ◽  
Standard Of Care ◽  
Target Volume ◽  
Conformal Radiation Therapy ◽  
Intensity Modulated ◽  
3D Crt

AbstractBackground and Purpose: Intensity-modulated radiation therapy (IMRT) is considered by many to be the standard of care in the delivery of external-beam radiotherapy treatments to the prostate. The purpose of this study is to assess the validity of the purported benefits of IMRT.Materials and Methods: Treatment plans were produced for 10 patients using both 3D conformal radiation therapy (3D-CRT) and IMRT, utilising the dose constraints recommended by the Radiation Therapy Oncology Group (RTOG) 0415 protocol. Three IMRT modalities used in this study were linear accelerator based IMRT, helical tomotherapy, and serial tomotherapy. The prescription to the target, 76 Gy, was the same for all plans.Results: In general the 3D-CRT plans satisfied the RTOG criteria for planning target volume (PTV) coverage, and met or bettered the dose criteria for the organs at risk. PTV coverage was more homogeneous for the IMRT plans than the 3D-CRT plans but not significantly improved.Conclusions: Technically, because the IMRT plans required greater effort for the optimisation, longer treatment times and higher monitor units, the use of IMRT for the fulfilment of the protocol’s dosimetric goals was not justified using these constraints.

scholarly journals Proton Versus Intensity-Modulated Radiation Therapy: First Dosimetric Comparison for Total Scalp Irradiation

2019 ◽  
Vol 6 (3) ◽  
pp. 19-26
Author(s):  
Ankur Markand Sharma ◽  
Emily Kowalski ◽  
Nathan McGovern ◽  
Mingyao Zhu ◽  
Mark Vikas Mishra
Keyword(s):  
Radiation Therapy ◽  
Organs At Risk ◽  
Treatment Plan ◽  
Intensity Modulated Radiation Therapy ◽  
High Dose ◽  
Proton Radiation ◽  
Dosimetric Comparison ◽  
Intensity Modulated ◽  
Volumetric Arc Therapy ◽  
Cutaneous Lymphomas

Abstract Purpose: Total scalp irradiation (TSI) is used to treat malignancies of the scalp and face, including angiosarcomas, nonmelanoma skin cancers, and cutaneous lymphomas. Owing to the irregularity of the scalp contour and the presence of underlying critical organs at risk (OARs), radiation planning is challenging and technically difficult. To address these complexities, several different radiation therapy techniques have been used. These include the combined lateral photon-electron technique (3DRT), intensity-modulated radiation therapy (IMRT)/volumetric arc therapy (VMAT), helical tomotherapy (HT), and mold-based high-dose-rate brachytherapy (HDR BT). However, the use of proton radiation therapy (PRT) has never been documented. Materials and Methods: A 71-year-old, immunosuppressed man presented with recurrent nonmelanoma skin cancer of the scalp. He was successfully treated at our center with PRT to deliver TSI. A comparative VMAT treatment plan was generated and dose to critical OARs was compared. Results: We present the first clinical case report of PRT for TSI and dosimetric comparison to a VMAT plan. The PRT and VMAT plans provided equivalent target volume coverage; however, the PRT plan significantly reduced dose to the brain, hippocampi, and optical apparatus. Conclusion: TSI planned with PRT is relatively straightforward from a planning perspective and does not require a bolus. It also has the potential to decrease radiation therapy–related toxicity. However, PRT is relatively expensive and not universally available. The uncertainty surrounding the end-range of the proton beam is a consideration. Although there are potential disadvantages to using PRT for TSI, its use should be considered by treating radiation oncologists and referring physicians.

A planning study to optimise a simultaneously integrated boost treatment of larynx cancer with seven intensity-modulated radiation therapy (IMRT) beams

2018 ◽  
Vol 17 (4) ◽  
pp. 447-454 ◽  
Author(s):  
M. Erraoudi ◽  
M. A. Youssoufi ◽  
F. Bentayeb ◽  
M. R. Malisan
Keyword(s):  
Radiation Therapy ◽  
Organs At Risk ◽  
Intensity Modulated Radiation Therapy ◽  
Conformal Radiotherapy ◽  
Target Volume ◽  
The Body ◽  
Larynx Cancer ◽  
Body Volume ◽  
Intensity Modulated ◽  
Integrated Boost

AbstractBackgroundIntensity-modulated radiation therapy (IMRT) is one of the most reported techniques for head and neck cancer treatment, as it allows a good coverage of the planning target volume (PTV) while sparing the surrounding organs at risk (OAR) better than conventional conformal radiotherapy. The objective of this work is to optimise an IMRT technique for the simultaneously integrated boost (SIB) treatment of larynx cancer delivering a total dose of 69·96 Gy to the boost volume and 54·45 Gy to the elective volume in 33 fractions.MethodsThree IMRT techniques, each using seven equally spaced beams, were planned for a sample of 10 patients. The first two techniques (IMRT-0 and IMRT-26) differ only for the starting angle of the seven beams, whereas the third (IMRT-CT) combines both these techniques by delivering IMRT-0 in the first half of treatment, and IMRT-26 in the second half, thus taking advantage of using 14 beams in total while using seven at a time only. The planning results were compared according to the dose coverage, homogeneity and conformity of the two PTVs, as well as to the dose to OARs, that is, spinal cord, parotids, mandible, brainstem and healthy tissue (defined as the body volume minus the sum of PTVs).ResultsBasically the PTV coverage resulted acceptable and comparable with all the three techniques. Concerning OARs, statistically better results are obtained in IMRT-CT when compared with IMRT-26 and IMRT-0.ConclusionThe IMRT-CT technique, combining two different seven-beam setups, delivered in two treatment phases, improves dose distribution without increasing delivery time.

scholarly journals Automated Intensity Modulated Radiation Therapy Treatment Planning for Cervical Cancer Based on Convolution Neural Network

2020 ◽  
Vol 19 ◽  
pp. 153303382095700
Author(s):  
Chen Jihong ◽  
Bai Penggang ◽  
Zhang Xiuchun ◽  
Chen Kaiqiang ◽  
Chen Wenjuan ◽  
...  
Keyword(s):  
Neural Network ◽  
Cervical Cancer ◽  
Radiation Therapy ◽  
Organs At Risk ◽  
Intensity Modulated Radiation Therapy ◽  
Convolution Neural Network ◽  
Average Dose ◽  
Planning Time ◽  
Intensity Modulated ◽  
Testing Set

Purpose: To develop and evaluate an automatic intensity-modulated radiation therapy (IMRT) program for cervical cancer, including a Convolution Neural Network (CNN)-based prediction model and an automated optimization strategy. Methods: A CNN deep learning model was trained to predict a patient-specify set of IMRT objectives based on overlap volume histograms (OVH) and high-quality plan of previous patients. A total of 140 cervical cancer patients were enrolled in this study, including 100 patients in the training set, 20 patients in the validation set and 20 patients in the testing set. The input of this model was OVH data and the output were values of IMRT plan objectives. For patients in the testing set, the set of planning objectives were predicted by the CNN model and used to automatically generate IMRT plans. Meanwhile, manual plans of these patients were generated by 1 beginner planner and 1 senior planner respectively. Finally, dose distribution, dosimetric parameters and planning time were analyzed. In addition, the 3 types of plans were blinded compared and ranked by an experienced oncologist. Results: There were almost no statistically differences among these 3 types of plans in target coverage and dose conformity. Dose homogeneity were slightly decreased while the average dose and parameters for most organs-at-risk (OARs) were decreased in automatic plans. Especially in comparison with manual plans by the beginner planner, V40 of bladder and rectum decreased 6.3% and 12.3%, while mean dose of rectum and marrow were 1.1 Gy and 1.8 Gy lower with automatic plans (either P < 0.017). In the blinded comparison, automatic plans were chosen as best plan in 14 cases. Conclusions: For cervical cancer, automatic IMRT plans optimized from the CNN generated objectives have superior dose sparing without compromising of target dose. It significantly reduced the planning time.

Quality assurance of intensity modulated radiation therapy treatment planning using head and neck phantom

2019 ◽  
Vol 18 (03) ◽  
pp. 239-245
Author(s):  
Zahra ◽  
Jalil ur Rehman ◽  
H M Noor ul Huda Khan Asghar ◽  
Nisar Ahmad ◽  
Zaheer Abbas Gilani ◽  
...  
Keyword(s):  
Quality Assurance ◽  
Radiation Therapy ◽  
Treatment Planning ◽  
Treatment Plan ◽  
Intensity Modulated Radiation Therapy ◽  
Planning System ◽  
Treatment Planning System ◽  
Intensity Modulated ◽  
Radiation Therapy Treatment Planning ◽  
Convolution Algorithm

AbstractPurposeThe purpose of this study is the verification of intensity modulated radiation therapy (IMRT) head neck treatment planning with one-dimensional and two-dimensional (2D) dosimeters using imaging and radiation oncology core (IROC) Houston head &amp; neck (H&amp;N) phantom.MethodThe image of the H&amp;N phantom was obtained by computed tomography scan which was then transferred to Pinnacle@3 treatment planning system (TPS) for treatment planning. The contouring of the target volumes and critical organ were done manually and dose constraints were set for each organ according to IROC prescription. The plan was optimised by adoptive convolution algorithm to meet the IROC criteria and collapse cone convolution algorithm calculated the delivered doses for treatment. Varian Clinac 2110 was used to deliver the treatment plan to the phantom, the process of irradiation and measurement were repeated three times for reproducibility and reliability. The treatment plan was verified by measuring the doses from thermoluminescent dosimeters (TLDs) and GafChromic external beam therapy 2 films. The agreement between the planned and delivered doses were checked by calculating the percentage dose differences, analysing their isodose line profiles and 2D gamma maps.ResultsThe average percent dose difference of 1·8% was obtained between computed doses by TPS and measured doses from TLDs, however these differences were found to be higher for organ at risk. The film dose profile was well in agreement with the planned dose distribution with distance to agreement of 1·5 mm. The gamma analysis of the computed and recorded doses passed the criteria of 3%/3 mm with passing percentages of &gt;96%, which shows successful authentication of delivered doses for IMRT.ConclusionIMRT pre-treatment validation can be done with IROC anthropomorphic phantoms, which is essential for the delivery of modulated radiotherapies. It was concluded that films and TLDs can be used as quality assurance tools for IMRT.

scholarly journals Systematic Quantitative Evaluation of Plan-IQ for Intensity-Modulated Radiation Therapy After Modified Radical Mastectomy

2021 ◽  
Author(s):  
Kunzhi Chen ◽  
Zhuangzhuang Zheng ◽  
Lijuan Ding ◽  
Na Tao ◽  
Libo Wang ◽  
...  
Keyword(s):  
Radiation Therapy ◽  
Quantitative Evaluation ◽  
Organs At Risk ◽  
Intensity Modulated Radiation Therapy ◽  
Radical Mastectomy ◽  
Target Volume ◽  
Modified Radical Mastectomy ◽  
Planning Strategy ◽  
Intensity Modulated ◽  
The Individual

Abstract Background and purpose: A systematic quantitative evaluation of the quality change of intensity-modulated radiation therapy (IMRT) using the Plan-IQ feasibility tool was performed for modified radical mastectomy.Materials and methods: We selected 50 patients with breast cancer treated with IMRT. All patients received the same dose in the planning target volume (PTV). Two plans were designed for each patient: the clinically accepted normal plan group (NP group) and the repeat plan group (RP group). An automated planning strategy was generated using a Plan-IQ feasibility dose volume histogram (FDVH) in RP group. These plans were assessed according to the dosimetry parameters. A detailed scoring strategy was based on the RTOG9804 report and 2018 National Comprehensive Cancer Network guidelines, combined with clinical experience.Results: PTV coverage in both groups was achieved at 100% of the prescribed dose. Except for the thyroid coverage, the dose limit of organs at risk (OAR) in RP group was significantly better than that in NP group. In the scoring analysis, the total score of RP group decreased compared to that of NP group (P < 0.05), and the individual scores of PTV and OAR significantly changed. PTV score in RP group decreased (P < 0.01); however, OAR score improved (P < 0.01).Conclusions: The Plan-IQ FDVH was useful for evaluating a class solution for IMRT planning. Plan-IQ can automatically help physicians design the best OAR protection plan, which sacrifices part of PTV, while still meeting clinical requirements.

Sign in / Sign up

Export Citation Format

Share Document