A Baseline Survey on the Treatment Workflow and Pediatric IGRT Practice Among European Members of the Project-Based Consortium and the Pediatric Radiation Oncology Society (PROS).

2020 ◽  
Author(s):  
Coen A.A. Windmeijer ◽  
Arjan Bel ◽  
Rianne de Jong ◽  
Brian V. Balgobind ◽  
Marianne C. Aznar ◽  
...  
Keyword(s):  
Radiation Oncology ◽  
Best Practice ◽  
Volumetric Modulated Arc Therapy ◽  
Intensity Modulated Radiotherapy ◽  
Conformal Radiotherapy ◽  
Target Volume ◽  
Baseline Survey ◽  
Image Guided Radiotherapy ◽  
Treatment Techniques ◽  
Pre Treatment

Abstract Background Image-guided radiotherapy (IGRT) enables high precision tumor treatment with potential for sparing healthy tissues. The value of pediatric IGRT is widely acknowledged, but there is no consensus on ‘best practice’. We aimed to assess clinical pediatric IGRT practice among European members of the Pediatric Radiation Oncology Society (PROS) and members of our project-based consortium.Methods A survey addressing radiotherapy preparation, planning and delivery in seven treatment sites was sent to European PROS members and/or our IGRT project-based consortium (70 institutes). Responses were collected from June-September 2018.Results Of the 42 responding institutes (response rate 60%), 33 indicated to treat children. 28/33 are photon-only institutes, 3/33 are dedicated proton (‘proton-only’) institutes and 2/33 use both. Immobilization includes facial masks (in 100% of brain, craniospinal axis (CSA) and head-and-neck (H&N) treatments), and vacuum cushions (all sites, except brain and H&N). Intensity-modulated radiotherapy and volumetric-modulated arc therapy are most frequently applied ranging from 71%-81% in respectively CSA (20/28), and extremities (21/26), followed by 3D conformal radiotherapy ranging from 36%-69% in respectively H&N (10/28), and extremities (18/26). Isotropic planning target volume (PTV) margins varied widely in brain and abdomen (range, 1-10mm). The use of in-room kilovolt cone-beam computed tomography ranges from 57%-86% in respectively CSA (16/28), and thorax (24/28). Daily online imaging is used by the majority of institutes, ranging from 85%-90% in respectively extremities (22/26) and pelvis (27/30). Offline imaging protocols are used by 14%-21% in respectively H&N (4/28) and thorax (6/28).Conclusions Our survey shows comparable practice in pre-treatment imaging, planning and treatment techniques, and IGRT application among the participating European institutes. However, wide ranges in PTV margin sizes exist, supporting the need to define international ‘best practice’ guidelines for pediatric IGRT, and to aim for consensus on optimal margin definitions in view of available IGRT facilities and workflows among institutes.

Monte Carlo (MC)-based volumetric modulated arc therapy (VMAT) in locally advanced esophageal cancer with potential for dose escalation.

2014 ◽  
Vol 32 (3_suppl) ◽  
pp. 77-77
Author(s):  
Shaakir Hasan ◽  
Anil Sethi ◽  
Jennifer Breunig ◽  
Gabriel Axelrud ◽  
William Small ◽  
...  
Keyword(s):  
Dose Escalation ◽  
Organs At Risk ◽  
Locally Advanced ◽  
Volumetric Modulated Arc Therapy ◽  
Intensity Modulated Radiotherapy ◽  
Conformal Radiotherapy ◽  
Target Volume ◽  
Target Dose ◽  
Treatment Techniques ◽  
Prescription Dose

77 Background: Previous attempts at dose escalation in esophagus radiotherapy (RT), mostly based on older planning techniques, have not shown improved outcomes. We aimed to investigate the importance of newer, sophisticated dose algorithms and treatment techniques in escalating target dose and reducing dose to organs at risk (OAR). Methods: Treatment plans for 10 patients were retrospectively evaluated using 3D conformal radiotherapy (3DCRT), MC based intensity modulated radiotherapy (IMRT), and VMAT. Prescription dose was 45 Gy to the planning target volume (PTV) in 25 fractions followed by a 5.4 Gy boost in 3 fractions. PTV (mean±s.d. = 681±236 cc) were planned with BrainLab iPlan 4.1 software as IMRT and VMAT. Dose distributions were calculated with both pencil beam (PB) and MC algorithms. Each PTV was normalized to receive at least 95% of 50.4 Gy or 60 Gy dose. OARs were evaluated as per RTOG1010 dose guidelines. Paired t-tests were used for statistical analysis. Results: IMRT vs. 3DCRT PTV 50.4 Gy: IMRT plans decreased heart and lung average Dmean by 4.7 Gy (p = 0.053) and 1.9 Gy (p = 0.001) respectively when compared to 3DCRT. In addition, average values of lung V5, V10, and V30 also reduced by 7.1%, 5.5%, and 3.6% respectively (p < 0.05). There was a 12.1% decrease in heart V40 (p=0.053) and 3.7% reduction in liver V30 (p=0.08). PTV 60Gy: IMRT plans at 60 Gy led to lower OAR doses compared to 3DCRT at 50.4 Gy. MC based IMRT results did not significantly differ from PB, with the exception of lung V5 which was 4.4% higher (p <0.001). VMAT vs. IMRT PTV 50.4 Gy: VMAT based planning, compared to IMRT, lowered V20 (3.4%, p=0.029), V30 (1.6%, p = 0.013), and spinal cord Dmax (5.4 Gy, p = 0.001). However, lung Dmean, V5, and V10 increased by 1.2 Gy, 11.7%, 16.7% respectively (p < 0.001). PTV 60 Gy: With VMAT planning, all OAR dose parameters were within the RTOG 1010 limits, although lung V5 and V10 exceeded acceptable limits by 1.6% and 2.6% respectively. Conclusions: Compared to 3DCRT, target dose escalation with IMRT and VMAT is possible with improved OAR dose sparing, as evaluated with MC algorithms. Increased dose values for V5 and V10 as seen in MC based VMAT plans call for reassessment of RTOG 1010 guidelines.

Dosimetric comparison of different radiotherapy techniques for the treatment of Retinoblastoma

2020 ◽  
pp. 1-6
Author(s):  
Jyotiman Nath ◽  
Pranjal Goswami ◽  
Partha Pratim Medhi ◽  
Gautam Sarma ◽  
Apurba Kumar Kalita ◽  
...  
Keyword(s):  
Organs At Risk ◽  
External Beam Radiotherapy ◽  
Volumetric Modulated Arc Therapy ◽  
Three Dimensional ◽  
Intensity Modulated Radiotherapy ◽  
Conformal Radiotherapy ◽  
Optic Chiasm ◽  
Target Volume ◽  
Target Coverage ◽  
Radiotherapy Techniques

Abstract Aim: This study aims to compare the dosimetric parameters among four different external beam radiotherapy techniques used for the treatment of retinoblastoma. Materials and methods: Computed tomography (CT) sets of five retinoblastoma patients who required radiotherapy to one globe were included. Four different plans were generated for each patient using three dimensional conformal radiotherapy (3DCRT), intensity modulated radiotherapy (IMRT), volumetric modulated arc therapy (VMAT) and VMAT using flattening filter free (VMAT-FFF) beam techniques. Plans were compared for target coverage and organs at risk (OARs) sparing. Results: The target coverage of planning target volume (PTV) for all the four modalities were clinically acceptable with a V95 of 95 ± 0%, 97·6 ± 1·87%, 99·3 ± 0·5% and 99·17 ± 0·45% for 3DCRT, IMRT, VMAT and VMAT-FFF respectively. The VMAT and IMRT plans had better target coverage than the 3DCRT plans (p = 0·001 and p = 0·07 respectively). IMRT and VMAT plans were also found superior to 3DCRT plans in terms of OAR sparing like brainstem, optic chiasm, brain (p < 0·05). VMAT delivered significantly lower dose to the brainstem and contralateral optic nerve in comparison to IMRT. Use of VMAT-FFF beams did not show any benefit over VMAT in target coverage and OAR sparing. Conclusion: VMAT should be preferred over 3DCRT and IMRT for treatment of retinoblastoma owing to better target coverage and less dose to most of the OARs. However, IMRT and VMAT should be used with caution because of the increased low dose volumes to the OARs like contralateral lens and eyeball.

scholarly journals Technical Advances and Pitfalls in Head and Neck Radiotherapy

2012 ◽  
Vol 2012 ◽  
pp. 1-13 ◽  
Author(s):  
Upendra Parvathaneni ◽  
George E. Laramore ◽  
Jay J. Liao
Keyword(s):  
Head And Neck ◽  
Planning Process ◽  
Treatment Plan ◽  
Intensity Modulated Radiotherapy ◽  
Conformal Radiotherapy ◽  
Standard Of Care ◽  
Target Volume ◽  
Image Guided Radiotherapy ◽  
Technical Advances ◽  
Set Up

Intensity Modulated Radiotherapy (IMRT) is the standard of care in the treatment of head and neck squamous cell carcinomas (HNSCC) based on level 1 evidence. Technical advances in radiotherapy have revolutionized the treatment of HNSCC, with the most tangible gain being a reduction in long term morbidity. However, these benefits come with a serious and sobering price. Today, there is a greater chance of missing the target/tumor due to uncertainties in target volume definition by the clinician that is demanded by the highly conformal planning process involved with IMRT. Unless this is urgently addressed, our patients would be better served with the historically practiced non conformal radiotherapy, than IMRT which promises lesser morbidity. Image guided radiotherapy (IGRT) ensures the level of set up accuracy warranted to deliver a highly conformal treatment plan and should be utilized with IMRT, where feasible. Proton therapy has a theoretical physical advantage over photon therapy due to a lack of “exit dose”. However, clinical data supporting the routine use of this technology for HNSCC are currently sparse. The purpose of this article is to review the literature, discuss the salient issues and make recommendations that address the gaps in knowledge.

A comprehensive evaluation of the quality and complexity of prostate IMRT and VMAT plans generated by an automated inverse planning tool

2021 ◽  
pp. 1-7
Author(s):  
Dean Wilkinson ◽  
Kelly Mackie ◽  
Dean Novy ◽  
Frances Beaven ◽  
Joanne McNamara ◽  
...  
Keyword(s):  
Dose Level ◽  
Comprehensive Evaluation ◽  
Volumetric Modulated Arc Therapy ◽  
Intensity Modulated Radiotherapy ◽  
Target Volume ◽  
Planning Tool ◽  
Inverse Planning ◽  
Dose Planning ◽  
Target Volumes ◽  
Lymph Node Irradiation

Abstract Introduction: The Pinnacle3 Auto-Planning (AP) package is an automated inverse planning tool employing a multi-sequence optimisation algorithm. The nature of the optimisation aims to improve the overall quality of radiotherapy plans but at the same time may produce higher modulation, increasing plan complexity and challenging linear accelerator delivery capability. Methods and materials: Thirty patients previously treated with intensity-modulated radiotherapy (IMRT) to the prostate with or without pelvic lymph node irradiation were replanned with locally developed AP techniques for step-and-shoot IMRT (AP-IMRT) and volumetric-modulated arc therapy (AP-VMAT). Each case was also planned with VMAT using conventional inverse planning. The patient cohort was separated into two groups, those with a single primary target volume (PTV) and those with dual PTVs of differing prescription dose levels. Plan complexity was assessed using the modulation complexity score. Results: Plans produced with AP provided equivalent or better dose coverage to target volumes whilst effectively reducing organ at risk (OAR) doses. For IMRT plans, the use of AP resulted in a mean reduction in bladder V50Gy by 4·2 and 4·7 % (p ≤ 0·01) and V40Gy by 4·8 and 11·3 % (p < 0·01) in the single and dual dose level cohorts, respectively. For the rectum, V70Gy, V60Gy and V40Gy were all reduced in the dual dose level AP-VMAT plans by an average of 2·0, 2·7 and 7·3 % (p < 0·01), respectively. A small increase in plan complexity was observed only in dual dose level AP plans. Findings: The automated nature of AP led to high quality treatment plans with improvement in OAR sparing and minimised the variation in achievable dose planning metrics when compared to the conventional inverse planning approach.

scholarly journals Dosimetric evaluation of the heart and left anterior descending artery dose in radiotherapy for Japanese patients with breast cancer

2019 ◽  
Vol 61 (1) ◽  
pp. 134-139
Author(s):  
Osamu Tanaka ◽  
Kousei Ono ◽  
Takuya Taniguchi ◽  
Chiyoko Makita ◽  
Masayuki Matsuo
Keyword(s):  
Breast Cancer ◽  
Volumetric Modulated Arc Therapy ◽  
Intensity Modulated Radiotherapy ◽  
Japanese Patients ◽  
Target Volume ◽  
The Other ◽  
High Coverage ◽  
Left Anterior Descending Artery ◽  
Treatment Plans ◽  
Field Static

Abstract Intensity-modulated radiotherapy (IMRT) has been used for breast cancer as well as in field-in-field techniques. Few dosimetric comparison studies have been conducted using IMRT and volumetric modulated arc therapy (VMAT) for Japanese patients. We aimed to study such patients. Thirty-two patients with left-sided breast cancer were enrolled. We conducted the following five treatment plans: two field-static IMRT (2F-S-IMRT), four field-static IMRT (4F-S-IMRT), 40° dual partial arc VMAT (40d-VMAT), 80° dual partial arc VMAT (80d-VMAT) and 210° partial VMAT (210p-VMAT). We evaluated the following: level of coverage of planning target volume (PTV) of 95% for irradiation at a dose of 50 Gy (D95) and the percentage of the heart and left anterior descending artery (LAD) volume that received 10 Gy or more (V10). As a result, the coverage of 40d-VMAT for the prescribed PTV dose of D95 was significantly lower than that of the other treatment plans (P &lt; 0.05). Regarding heart V10 and LAD V10, 2F-S-IMRT, 40d-VMAT and 80d-VMAT showed significantly lower dose than the other treatment plans (P &lt; 0.05). In conclusion, among the five plans, 2F-S-IMRT is recommended for Japanese patients because of high coverage of D95 of PTV, low V10 of the heart and LAD and the monitor unit value was the lowest.

Is 5 mm breath-hold window (BHW) sufficient to treat carcinoma left breast patients post-conservative surgery: a comparative study using forward intensity-modulated radiotherapy (FIMRT) and volumetric modulated arc therapy (VMAT)

2020 ◽  
pp. 1-9
Author(s):  
Karthikeyan Kalyanasundaram ◽  
Subramani Vellaiyan
Keyword(s):  
Breathing Pattern ◽  
Volumetric Modulated Arc Therapy ◽  
Intensity Modulated Radiotherapy ◽  
Conservative Surgery ◽  
Target Volume ◽  
Left Breast ◽  
Breath Hold ◽  
Deep Inspiration ◽  
Intensity Modulated ◽  
Arc Therapy

Abstract Purpose: The purpose of the study was to evaluate the impact of changes in breathing pattern inside the breath-hold window (BHW) during deep inspiration breath hold treatment for carcinoma left breast patients post-conservative surgery. Methods: Ten patients of carcinoma left breast post-conservative surgery were prospectively selected. Three sets of CT plain images were acquired, one with 5 mm deep inspiration BHW (DIBHR) and the other one with 1 mm BHW matching the lower threshold (DIBHL) and the third one with 1 mm BHW matching the upper threshold (DIBHH) as DIBHR. For all patients, forward intensity-modulated radiotherapy (FIMRT) and volumetric modulated arc therapy (VMAT) plans were generated in the 5 mm BHW CT series and the same plan being copy and pasted in other series. Target volume doses and critical structure doses were tabulated. Results: Planning target volume coverage was adequate and no significant differences were found in any CT series. Significant differences noted in average left lung V5%, V10% and V18% doses between DIBHR versus DIBHH (p values = 0·0461, 0·0283 and 0·0213, respectively) and DIBHL versus DIBHH (p values = 0·0434, 0·0484 and 0·0334, respectively) for FIMRT plans and V18% doses in DIBHR versus DIBHH (p = 0·0067) in VMAT. No differences in heart and apex of heart doses were found. Left anterior descending artery (LAD) mean doses were significant in DIBHL versus DIBHR, DIBHR versus DIBHH and DIBHL versus DIBHH (p = 0·0012, 0·0444 and 0·0048, respectively) series for FIMRT plans and DIBHR versus DIBHH and DIBHL versus DIBHH (p = 0·0341, 0·0001) for VMAT plans. Finding: The changes in the breathing pattern inside DIBH window level cause some variation in LAD doses and no other significant differences in any parameters noted, so care should be taken while treating patients with preexisting cardiac conditions.

The impact of image-guided radiotherapy (IGRT) for prostate cancer (PC) on radiotherapy (RT)-related acute toxicities and prostate-specific antigen (PSA) kinetics.

2012 ◽  
Vol 30 (15_suppl) ◽  
pp. e15110-e15110 ◽  
Author(s):  
Darren M. C. Poon ◽  
CM Leung ◽  
CM Chu ◽  
WY Lee ◽  
Louis Lee ◽  
...  
Keyword(s):  
Image Guidance ◽  
Prostate Gland ◽  
Specific Antigen ◽  
Three Dimensional ◽  
Intensity Modulated Radiotherapy ◽  
Image Guided Radiotherapy ◽  
Psa Kinetics ◽  
Significant Difference ◽  
Pre Treatment ◽  
The Impact

e15110 Background: IGRT for PC could potentially improve the therapeutic ratio by enhancing accuracy of delivery of radiation to the prostate gland. Our aim is to compare the treatment outcomes in terms of RT-related acute toxicities and PSA kinetics of PC patients (pts) undergoing radical intensity-modulated radiotherapy (IMRT) with or without image-guidance. Methods: A cohort of 21 consecutive pts treated by IGRT (I) from January 2010, when the IGRT system was introduced in our institution, was compared with an immediately precedent cohort of 21 pts receiving IMRT without image-guidance (Non-I). The prescription dose (76Gy in 38 fractions) and the treatment margins were the same between the 2 groups (gps). In the I gp, daily online verification and correction of treatment position was performed with reference to image registration of the daily pre-treatment on-board imaging with the corresponding digitally reconstructed radiographs, based on three-dimensional matching of three intra-prostatic fiducial markers. Androgen deprivation therapy was not used in both gps. Acute toxicities were scored weekly during the course of RT according to the Common Terminology Criteria for Adverse Events Version 4.02. The pre- and the post-RT PSA within 6 months after completion of RT were obtained. The PSA halving time (PSAHT) was calculated by first order kinetics. Results: There was no statistically significant difference regarding the baseline clinical characteristics (age, PSA at diagnosis, Gleason score, T staging) between the gps. No grade 3 or 4 acute genitourinary (GU) or gastrointestinal (GI) toxicities was encountered in either gps. Acute grade 1 or 2 GI toxicities were significantly less frequent in the I gp (23.8% vs 81.0%, p=0.001), and their median duration of such toxicity were also significantly shorter (0.33 week vs 1.38 week, p=0.004).The frequencies of acute grade 1 or 2 GU toxicities were comparable between both gps (66.6% vs 81.0%, p=0.45).The I gp had a shorter median PSAHT than the non-I gp (3.36 week vs 5.49 week, p=0.09). Conclusions: IGRT is effective in reducing acute GI toxicities in treatment of PC, and may have more favorable PSA kinetics.

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