scholarly journals A Hybrid IMRT/VMAT Technique for the Treatment of Nasopharyngeal Cancer

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Nan Zhao ◽  
Ruijie Yang ◽  
Yuliang Jiang ◽  
Suqing Tian ◽  
Fuxin Guo ◽  
...  
Keyword(s):  
Organs At Risk ◽  
Volumetric Modulated Arc Therapy ◽  
Nasopharyngeal Cancer ◽  
Intensity Modulated Radiotherapy ◽  
Delivery Time ◽  
Target Dose ◽  
Arc Therapy ◽  
Dose Homogeneity ◽  
The Mean ◽  
Delivery Efficiency

Hybrid IMRT/VMAT technique which combined intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) was developed for the treatment of nasopharyngeal cancer (NPC). Two-full-arc VMAT (2ARC-VMAT), 9-field IMRT (9F-IMRT), and Hybrid IMRT/VMAT plans for NPC were compared in terms of the dosimetric quality, sparing of organs at risk (OARs), and delivery efficiency. The Hybrid IMRT/VMAT technique can improve the target dose homogeneity and conformity compared with 9F-IMRT and 2ARC-VMAT. It can reduce the dose delivered to the TMJ, mandible, temporal lobe, and unspecified tissue with fewer MUs compared with 9F-IMRT and dose delivered to parotids, brainstem, and spinal cord compared with 2ARC-VMAT technique. The mean delivery time of Hybrid plans was shorter than that of 9F-IMRT plans (408 s versus 812 s;P=0.00) and longer than that of 2ARC-VMAT plans (408 s versus 179 s;P=0.00). Hybrid IMRT/VMAT technique could be a viable radiotherapy technique with better plan quality.

scholarly journals Dosimetric comparison for volumetric modulated arc therapy and intensitymodulated radiotherapy on the left-sided chest wall and internal mammary nodes irradiation in treating post-mastectomy breast cancer

2015 ◽  
Vol 49 (1) ◽  
pp. 91-98 ◽  
Author(s):  
Qian Zhang ◽  
Xiao Li Yu ◽  
Wei Gang Hu ◽  
Jia Yi Chen ◽  
Jia Zhou Wang ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Volumetric Modulated Arc Therapy ◽  
Target Volume ◽  
Contralateral Breast ◽  
Delivery Time ◽  
Internal Mammary Nodes ◽  
Arc Therapy ◽  
Internal Mammary ◽  
Dose Homogeneity ◽  
The Mean

AbstractBackground. The aim of the study was to evaluate the dosimetric benefit of applying volumetric modulated arc therapy (VMAT) on the post-mastectomy left-sided breast cancer patients, with the involvement of internal mammary nodes (IMN).Patients and methods. The prescription dose was 50 Gy delivered in 25 fractions, and the clinical target volume included the left chest wall (CW) and IMN. VMAT plans were created and compared with intensity-modulated radiotherapy (IMRT) plans on Pinnacle treatment planning system. Comparative endpoints were dose homogeneity within planning target volume (PTV), target dose coverage, doses to the critical structures including heart, lungs and the contralateral breast, number of monitor units and treatment delivery time.Results. VMAT and IMRT plans showed similar PTV dose homogeneity, but, VMAT provided a better dose coverage for IMN than IMRT (p = 0.017). The mean dose (Gy), V30(%) and V10(%) for the heart were 13.5 ± 5.0 Gy, 9.9% ± 5.9% and 50.2% ± 29.0% by VMAT, and 14.0 ± 5.4 Gy, 10.6% ± 5.8% and 55.7% ± 29.6% by IMRT, respectively. The left lung mean dose (Gy), V20(%), V10(%) and the right lung V5(%) were significantly reduced from 14.1 ± 2.3 Gy, 24.2% ± 5.9%, 42.4% ± 11.9% and 41.2% ± 12.3% with IMRT to 12.8 ± 1.9 Gy, 21.0% ± 3.8%, 37.1% ± 8.4% and 32.1% ± 18.2% with VMAT, respectively. The mean dose to the contralateral breast was 1.7 ± 1.2 Gy with VMAT and 2.3 ± 1.6 Gy with IMRT. Finally, VMAT reduced the number of monitor units by 24% and the treatment time by 53%, as compared to IMRT.Conclusions. Compared to 5-be am step-and-shot IMRT, VMAT achieves similar or superior target coverage and a better normal tissue sparing, with fewer monitor units and shorter delivery time.

scholarly journals Treatment planning comparison of volumetric modulated arc therapy with Trilogy and Halcyon for bilateral breast cancer

2021 ◽  
Author(s):  
Tao Sun ◽  
Xiutong Lin ◽  
Guifang Zhang ◽  
Qingtao Qiu ◽  
Chengqiang Li ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Treatment Planning ◽  
Volumetric Modulated Arc Therapy ◽  
Bilateral Breast Cancer ◽  
Planning System ◽  
Skin Dose ◽  
Delivery Time ◽  
Dose Volume ◽  
Arc Therapy ◽  
The Mean

Abstract Background: The Halcyon is a new machine from the Varian company. The purpose of this study was to evaluate the dosimetry of the Halcyon in treatment of bilateral breast cancer with volumetric modulated arc therapy. Methods: On CT images of 10 patients with bilateral breast cancer, four Halcyon plans with different setup fields were generated, and dosimetric comparisons using Bonferroni’s multiple comparisons test were conducted among the four plans. Whole and partial arc plans on the Trilogy and the Halcyon, referred to as T-4arc, T-8arc, H-4arc and H-8arc, were designed. The prescription dose was 50 Gy in 2-Gy fractions. All plans were designed with the Eclipse version 15.5 treatment planning system. The dosimetric differences between whole and partial arc plans in the same accelerator were compared using the Mann-Whitney U test. The better Halcyon plan was selected for the further dosimetric comparison of the plan quality and delivery efficiency between the Trilogy and the Halcyon. Results:Halcyon plans with high‐quality megavoltage cone beam CT setup fields increased the Dmean, D2 and V107 of the planning target volume (PTV) and the V5 and Dmean of the heart, left ventricle (LV) and lungs compared with other Halcyon setup plans. The mean dose and low dose volume of the heart, lungs and liver were significantly decreased in T-8arc plans compared to T-4arc plans. In terms of the V5, V20, V30, V40 and Dmean of the heart, the V20, V30, V40 and Dmean of the LV, the V30, V40, Dmax and Dmean of the left anterior descending artery (LAD), and the V5 and V40 of lungs, H-8arc was significantly higher than H-4arc (p<0.05). Compared with the Trilogy’s plans, the Halcyon’s plans reduced the high-dose volume of the heart and LV but increased the mean dose of the heart. For the dose of the LAD and the V20 and V30 of lungs, there was no significant difference between the two accelerators. Compared with the Trilogy, plans on the Halcyon significantly increased the skin dose but also significantly reduced the delivery time. Conclusion: For the Halcyon, the whole-arc plans have more dosimetric advantages than partial-arc plans in bilateral breast cancer radiotherapy. Although the mean dose of the heart and the skin dose are increased, the doses of the cardiac substructure and other OARs are comparable to the Trilogy, and the delivery time is significantly reduced.

scholarly journals Treatment planning comparison of volumetric modulated arc therapy with the trilogy and the Halcyon for bilateral breast cancer

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Tao Sun ◽  
Xiutong Lin ◽  
Guifang Zhang ◽  
Qingtao Qiu ◽  
Chengqiang Li ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Treatment Planning ◽  
Volumetric Modulated Arc Therapy ◽  
Bilateral Breast Cancer ◽  
Planning System ◽  
Skin Dose ◽  
Delivery Time ◽  
Dose Volume ◽  
Arc Therapy ◽  
The Mean

Abstract Background The Halcyon is a new machine from the Varian company. The purpose of this study was to evaluate the dosimetry of the Halcyon in treatment of bilateral breast cancer with volumetric modulated arc therapy. Methods On CT images of 10 patients with bilateral breast cancer, four Halcyon plans with different setup fields were generated, and dosimetric comparisons using Bonferroni’s multiple comparisons test were conducted among the four plans. Whole and partial arc plans on the Trilogy and the Halcyon, referred to as T-4arc, T-8arc, H-4arc and H-8arc, were designed. The prescription dose was 50 Gy in 2-Gy fractions. All plans were designed with the Eclipse version 15.5 treatment planning system. The dosimetric differences between whole and partial arc plans in the same accelerator were compared using the Mann–Whitney U test. The better Halcyon plan was selected for the further dosimetric comparison of the plan quality and delivery efficiency between the Trilogy and the Halcyon. Results Halcyon plans with high‐quality megavoltage cone beam CT setup fields increased the Dmean, D2 and V107 of the planning target volume (PTV) and the V5 and Dmean of the heart, left ventricle (LV) and lungs compared with other Halcyon setup plans. The mean dose and low dose volume of the heart, lungs and liver were significantly decreased in T-8arc plans compared to T-4arc plans. In terms of the V5, V20, V30, V40 and Dmean of the heart, the V20, V30, V40 and Dmean of the LV, the V30, V40, Dmax and Dmean of the left anterior descending artery (LAD), and the V5 and V40 of lungs, H-8arc was significantly higher than H-4arc (p < 0.05). Compared with the Trilogy’s plans, the Halcyon’s plans reduced the high-dose volume of the heart and LV but increased the mean dose of the heart. For the dose of the LAD and the V20 and V30 of lungs, there was no significant difference between the two accelerators. Compared with the Trilogy, plans on the Halcyon significantly increased the skin dose but also significantly reduced the delivery time. Conclusion For the Halcyon, the whole-arc plans have more dosimetric advantages than partial-arc plans in bilateral breast cancer radiotherapy. Although the mean dose of the heart and the skin dose are increased, the doses of the cardiac substructure and other OARs are comparable to the Trilogy, and the delivery time is significantly reduced.

Volumetric modulated arc therapy: a dosimetric comparison with dynamic IMRT and step-and-shoot IMRT

2019 ◽  
Vol 19 (4) ◽  
pp. 393-398 ◽  
Author(s):  
Payal Raina ◽  
Sudha Singh ◽  
Rajanigandha Tudu ◽  
Rashmi Singh ◽  
Anup Kumar
Keyword(s):  
Organs At Risk ◽  
Volumetric Modulated Arc Therapy ◽  
Intensity Modulated Radiation Therapy ◽  
Target Volume ◽  
Planning System ◽  
Treatment Planning System ◽  
Conformity Index ◽  
Delivery Time ◽  
Arc Therapy ◽  
Step And Shoot

AbstractAim:The aim of this study was to compare volumetric modulated arc therapy (VMAT) with dynamic intensity-modulated radiation therapy (dIMRT) and step-and-shoot IMRT (ssIMRT) for different treatment sites.Materials and methods:Twelve patients were selected for the planning comparison study. This included three head and neck, three brain, three rectal and three cervical cancer patients. Total dose of 50 Gy was given for all the plans. Plans were done for Elekta synergy with Monaco treatment planning system. All plans were generated with 6 MV photons beam. Plan evaluation was based on the ability to meet the dose volume histogram, dose homogeneity index, conformity index and radiation delivery time, and monitor unit needs to deliver the prescribed dose.Results:The VMAT and dIMRT plans achieved the better conformity (CI98% = 0·965 ± 0·023) and (CI98% = 0·939 ± 0·01), respectively, while ssIMRT plans were slightly inferior (CI98% = 0·901 ± 0·038). The inhomogeneity in the planning target volume (PTV) was highest with ssIMRT with HI equal to 0·097 ± 0·015 when compared to VMAT with HI equal to 0·092 ± 0·0369 and 0·095 ± 0·023 with dIMRT. The integral dose is found to be inferior with VMAT 105·31 ± 53·6 (Gy L) when compared with dIMRT 110·75 ± 52·9 (Gy L) and ssIMRT 115 38 ± 55·1(Gy L). All the techniques respected the planning objective for all organs at risk. The delivery time per fraction for VMAT was much lower than dIMRT and ssIMRT.Findings:Our results indicate that dIMRT and VMAT provide better sparing of normal tissue, homogeneity and conformity than ssIMRT with reduced treatment delivery time.

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.

Two-arc volumetric modulated arc therapy to provide dosimetric advantages for pancreas stereotactic body radiotherapy.

2016 ◽  
Vol 34 (4_suppl) ◽  
pp. 445-445
Author(s):  
Jason K Molitoris ◽  
Christopher Brown ◽  
Shifeng Chen ◽  
Kimberly Marter ◽  
Kristin Spaeth ◽  
...  
Keyword(s):  
Normal Tissue ◽  
Locally Advanced ◽  
Volumetric Modulated Arc Therapy ◽  
Advanced Pancreatic Cancer ◽  
Intensity Modulated Radiotherapy ◽  
Target Volume ◽  
Breath Hold ◽  
Target Coverage ◽  
Delivery Time ◽  
Arc Therapy

445 Background: Stereotactic body radiation therapy(SBRT) is increasingly used in locally advanced pancreatic cancer (LAPC). SBRT can be delivered using 3D conformal, static intensity modulated radiotherapy (IMRT), and volumetric modulated arc therapy (VMAT) techniques. Prior data suggest advantages of using VMAT over IMRT for single-fraction pancreas SBRT. We performed the first dosimetric comparison of IMRT with one and two arc VMAT for 5-fraction pancreas SBRT, a more commonly used regimen. Methods: We generated 5-fraction SBRT plans for 12 LAPC patients who were previously treated at our institution with standard fractionation. The prescription dose was 33 Gy delivered in 6.6 Gy fractions. Assuming breath hold, 3 plans were generated for each patient: 9-beam static IMRT, 1-arc VMAT (VMAT1), and 2-arc VMAT (VMAT2) targeting the primary tumor. Target coverage and normal tissue doses were compared between the delivery techniques. Results: Each plan met target coverage planning goals. More VMAT2 plans (100%) were able to meet all normal tissue constraints than VMAT1 (83.3%) or IMRT (75%). Duodenal dose was most lowest for VMAT2 compared to VMAT1 and IMRT for mean dose (8.66 vs. 9.00 vs. 8.99 Gy); D4% (25.9 vs. 26.6 vs. 26.3 Gy); V10Gy (38.02 vs. 39.33 vs. 40.11%), V15Gy (23.98 vs. 25.88 vs. 25.97%), V20Gy (12.73 vs. 13.84 vs. 14.95%), and V25Gy (5.96 vs. 6.85 vs. 6.78%)(all p < 0.05). The tumors closest to the duodenum had statistically significantly improved V30Gy for VMAT2 compared to VMAT1 and IMRT (both p < 0.001). VMAT1 and VMAT2 reduced dose to the stomach, spinal cord, and liver compared to IMRT; kidney dose, however, was lowest using IMRT. VMAT2 plans had the highest conformity, but required the most monitor units to deliver. Delivery time was significantly longer with IMRT, compared to VMAT1 and VMAT2 (8.25 vs. 2.16 vs. 3.33 mins). Conclusions: These data suggest that VMAT2 should be strongly considered for 5-fraction pancreas SBRT because of superior normal tissue sparing, more conformal target volume coverage, and faster treatment delivery time (compared to IMRT). Further evaluation is needed to clarify whether the dosimetric advantages of VMAT2 are clinically significant.

Dosimetric comparison between intensity-modulated radiotherapy and volumetric-modulated arc therapy in hippocampus sparing in brain metastasis treated by whole-brain irradiation and simultaneous integrated boost

2019 ◽  
Vol 19 (1) ◽  
pp. 45-51 ◽  
Author(s):  
Ehab Saad ◽  
Khaled Elshahat ◽  
Hussein Metwally
Keyword(s):  
Brain Metastasis ◽  
Organs At Risk ◽  
Volumetric Modulated Arc Therapy ◽  
Intensity Modulated Radiotherapy ◽  
Simultaneous Integrated Boost ◽  
Conformity Index ◽  
Whole Brain ◽  
Intensity Modulated ◽  
Arc Therapy ◽  
Integrated Boost

AbstractBackground:While treating brain metastasis with whole-brain radiotherapy incorporating a simultaneous integrated boost (WBRT-SIB), the risk of hippocampus injury is high. The aim of this study is to compare dosimetrically between intensity-modulated radiotherapy (IMRT) and volumetric-modulated arc therapy (VMAT) in sparing of hippocampus and organs at risk (OARs) and planning target volume (PTV) coverage.Methods:In total, 16 patients presenting with more than one brain metastases were previously treated and then retrospectively planned using VMAT and IMRT techniques. For each patient, a dual-arc VMAT and another IMRT (five beams) plans were created. For both techniques, 30 Gy in 10 fractions was prescribed to the whole brain (WB) minus the hippocampi and 45 Gy in 10 fractions to the tumour with 0·5 cm margin. Dose–volume histogram (DVH), conformity index (CI) and homogeneity index (HI) of PTV, hippocampus mean and maximum dose and other OARs for both techniques were calculated and compared.Results:A statistically significant advantage was found in WB-PTV CI and HI with VMAT, compared to IMRT. There were lower hippocampus mean and maximum doses in VMAT than IMRT. The maximum hippocampus dose ranged between 15·5 and 19·2 Gy and between 18·4 and 20·6 Gy in VMAT and IMRT, respectively. The mean dose of the hippocampus ranged between 11·5 and 17·7 Gy and between 13·2 and 18·3 Gy in VMAT and IMRT, respectively.Conclusion:Using WBRT-SIB technique, VMAT showed better PTV coverage with less mean and maximum doses to the hippocampus than IMRT. Clinical randomised studies are needed to confirm safety and clinical benefit of WBRT-SIB.

scholarly journals Treatment Planning Comparison of Volumetric Modulated Arc Therapy With Trilogy and Halcyon for Bilateral Breast Cancer 

2020 ◽  
Author(s):  
Tao Sun ◽  
Xiutong Lin ◽  
Guifang Zhang ◽  
Qingtao Qiu ◽  
Chengqiang Li ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Volumetric Modulated Arc Therapy ◽  
Bilateral Breast Cancer ◽  
Skin Dose ◽  
High Dose ◽  
Delivery Time ◽  
Breast Cancer Radiotherapy ◽  
Dose Volume ◽  
Arc Therapy ◽  
The Mean

Abstract Background: To evaluate the dosimetry of Halcyon in treatment of bilateral breast cancer with volumetric modulated arc therapy. Methods: On CT images of 10 patients with bilateral breast cancer, four Halcyon plans with different setup fields were generated and dosimetric comparisons were conducted among the four plans to select an optimal setup field mode. The four setup-field plans were referred to as CBCT-H, CBCT-L, MV-H, MV-L. Whole and partial arc plans on Trilogy and Halcyon referred to as T-4arc, T-8arc, H-4arc and H-8arc were designed. The dosimetric differences between whole and partial arc plans in the same accelerator were compared to understand the most suitable field setting mode. The better Halcyon plan was selected to the further dosimetric comparison of the plan quality and delivery efficiency between Trilogy and Halcyon. Results: CBCT-H plans increased Dmean, D2 and V107 of planning target volume (PTV) and V5 and Dmean of the heart, left ventricle (LV) and lungs compared to other plans. No significantly dosimetric differences were observed in PTV and organs at risk (OARs) among CBCT-L, MV-H and MV-L. The mean dose and low dose volume of heart, lungs and liver were significantly decreased in T-8arc plans. In terms of V5, V20, V30, V40 and Dmean of the heart, V20, V30, V40 and Dmean of the LV, V30, V40, Dmax and Dmean of the left anterior descending artery (LAD), V5 and V40 of lungs, H-8arc was significantly higher than H-4arc (p<0.05). Compared to Trilogy’s plans, Halcyon’s plans reduced the high-dose volume of the heart and LV, but increased the mean dose of the heart. For the dose of the LAD and the V20, V30 of lungs, there was no statistical difference between the two accelerators. Compared with Trilogy, plans on Halcyon significantly increased the skin dose, but also significantly reduced the delivery time. Conclusion: For Halcyon, the whole-arc plans has more dosimetric advantages in bilateral breast cancer radiotherapy. Although the mean dose of the heart and the skin dose are increased, the dose of the cardiac substructure and other OARs are comparable to the Trilogy, and the delivery time is significantly reduced.

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