scholarly journals CyberKnife and EDGE in stereotactic body radiotherapy for pancreas cancer: a comparison of plan quality

2020 ◽  
Author(s):  
Zhitao Dai ◽  
Li Ma ◽  
Tingting Cao ◽  
Lian Zhu ◽  
Man Zhao ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Stereotactic Body Radiotherapy ◽  
Normal Tissue ◽  
Pancreas Cancer ◽  
Target Volume ◽  
Conformity Index ◽  
Equivalent Uniform Dose ◽  
Dose Distributions ◽  
Dose Volume ◽  
Comprehensive Comparison

Abstract Purpose: To perform a comprehensive comparison of the different stereotactic body radiotherapy (SBRT) plans between the Varian EDGE and CyberKnife (CK) systems for pancreas cancer.Materials and methods: Fifteen patients with pancreas cancer were selected in this study. The median planning target volume (PTV) was 28.688cm 3 (5.736 to 49.246 cm 3 ). The SBRT plans for the EDGE and CK were generated in the Eclipse and Multiplan systems respectively with the same contouring and dose constrains for PTV and organ at risk (OAR). Dose distributions in PTV were evaluated in terms of coverage, conformity index (CI), new conformity index (nCI), homogeneity index (HI), and gradient index (GI). OARs, including spinal cord, bowel, stomach, duodenum and kidneys were statistically evaluated by different dose-volume metrics and equivalent uniform dose (EUD) . The volume covered by the different isodose lines (ISDL) ranging from 10% to 100% for normal tissue were also analyzed.Results: All SBRT plans for EDGE and CK met the clinical requirement for PTV and OARs. . For the PTV, the dosimetric metrics in EDGE plans were lower than that in CK, except that D 99 and GI were slightly higher. The EDGE plans with lower CI , nCI and HI were superior to offer the better conformity and homogeneity for PTV. For the normal tissue, the CK plans were better at OARs sparing. The radiobiological indices EUD of spinal cord, duodenum, stomach, and kidneys were lower for CK plans, except that liver were higher. The volumes of normal tissue covered by medium ISDLs (with range of 20%~70%) were lower for CK plans while that covered by high and low ISDLs were lower for EDGE plans.Conclusions: This study indicated that both EDGE and CK generated equivalent plan quality, and both systems can be considered as beneficial techniques for SBRT of pancreas cancer. EDGE plans offered the better conformity and homogeneity of dose distributions for PTV, while the CK plans could minimize the exposure of OARs.

scholarly journals Dosimetric and radiobiological comparison of treatment plan between CyberKnife and EDGE in stereotactic body radiotherapy for pancreatic cancer

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Zhi-tao Dai ◽  
Li Ma ◽  
Ting-ting Cao ◽  
Lian Zhu ◽  
Man Zhao ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Spinal Cord ◽  
Stereotactic Body Radiotherapy ◽  
Dose Distribution ◽  
Normal Tissue ◽  
Organs At Risk ◽  
Treatment Plan ◽  
Locally Advanced ◽  
Conformity Index ◽  
Homogeneous Dose

AbstractTo perform a comparison of the different stereotactic body radiotherapy (SBRT) plans between the Varian EDGE and CyberKnife (CK) systems for locally advanced unresectable pancreatic cancer. Fifteen patients with pancreatic cancer were selected in this study. The median planning target volume (PTV) was 28.688 cm3 (5.736–49.246 cm3). The SBRT plans for the EDGE and CK were generated in the Eclipse and Multiplan systems respectively with the same contouring and dose constrains for PTV and organs at risk (OARs). Dose distributions in PTV were evaluated in terms of coverage, conformity index (CI), new conformity index (nCI), homogeneity index (HI), and gradient index (GI). OARs, including spinal cord, bowel, stomach, duodenum and kidneys were statistically evaluated by different dose-volume metrics and equivalent uniform dose (EUD). The volume covered by the different isodose lines (ISDL) ranging from 10 to 100% for normal tissue were also analyzed. All SBRT plans for EDGE and CK met the dose constraints for PTV and OARs. For the PTV, the dosimetric metrics in EDGE plans were lower than that in CK, except that D99 and GI were slightly higher. The EDGE plans with lower CI, nCI and HI were superior to generate more conformal and homogeneous dose distribution for PTV. For the normal tissue, the CK plans were better at OARs sparing. The radiobiological indices EUD of spinal cord, duodenum, stomach, and kidneys were lower for CK plans, except that liver were higher. The volumes of normal tissue covered by medium ISDLs (with range of 20–70%) were lower for CK plans while that covered by high and low ISDLs were lower for EDGE plans. This study indicated that both EDGE and CK generated equivalent plan quality, and both systems can be considered as beneficial techniques for SBRT of pancreatic cancer. EDGE plans offered more conformal and homogeneous dose distribution for PTV, while the CK plans could minimize the exposure of OARs.

scholarly journals Stereotactic body radiotherapy with a single isocentre for multiple pulmonary metastases

2020 ◽  
Vol 6 (4) ◽  
pp. 20190121
Author(s):  
Ryuji Nakamura ◽  
Jun Sugawara ◽  
Satoshi Yamaguchi ◽  
Hisao Kakuhara ◽  
Koyo Kikuchi ◽  
...  
Keyword(s):  
Stereotactic Body Radiotherapy ◽  
Pulmonary Metastases ◽  
Target Volume ◽  
Conformity Index ◽  
Left Shoulder ◽  
Dose Volume ◽  
Lower Lung ◽  
The Mean ◽  
The Individual ◽  
Individual Tumour

A 45-year-old male developed a second set of pulmonary metastases 5 years after surgery for extraskeletal mucinous chondrosarcoma of the left shoulder. He already underwent a lobectomy and two segmentectomies for a first set of pulmonary metastases 2 years ago. The closely grouped three nodules within the left lower lung formed a planning target volume (PTV) for stereotactic body radiotherapy (SBRT) with a single isocentre, which was focused on the centre of the largest nodule (the simultaneous plan). Dose-volume histogram analysis confirmed that the plan was superior to an alternative plan, in which SBRT plans would have been produced for each individual tumour (the individual plan). The mean, maximum and minimum PTV doses were 54.0, 57.5 and 47.3 Gy, respectively, in the simultaneous plan, and 65.6, 87.2 and 52.3 Gy, respectively, in the individual plan. The homogeneity index, conformity index, and the maximum dose delivered to the surrounding healthy lung were 1.21, 0.71, and 37.7 Gy, respectively, in the simultaneous plan and 1.66, 4.44, and 46.2 Gy, respectively, in the individual plan. The patient developed Grade two pneumonitis, but remained healthy until 4 years after the SBRT. When multiple closely grouped metastases are treated using SBRT, the use of a single isocentre should be considered.

scholarly journals Dosimetric and biological comparison of treatment plans between EDGE and CyberKnife systems in stereotactic body radiation therapy for localized prostate cancer

2020 ◽  
Author(s):  
Zhitao Dai ◽  
Lian Zhu ◽  
Tingting Cao ◽  
Aihua Wang ◽  
Xueling Guo ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Radiation Therapy ◽  
Normal Tissue ◽  
Stereotactic Body Radiation Therapy ◽  
Localized Prostate Cancer ◽  
Conformity Index ◽  
Delivery Time ◽  
Plan Quality ◽  
Dose Volume ◽  
Treatment Plans

Abstract Aims: The aim of this study was to make a quantitative comparison of plan quality between MLC-based EDGE system and the cone-based CyberKnife system in stereotactic body radiation therapy (SBRT) for patients with localized prostate cancer.Materials and methods: Ten patients with prostate volumes ranging from 34.65 to 82.16 cc were used for prostate SBRT. Treatment plans were created for both EDGE and CyberKnife G4 systems using the same dose-volume constraints. Dosimetric indices including Planning Tumor Volume (PTV) coverage, conformity index (CI), new conformity index (nCI), homogeneity index (HI), gradient index (GI) were applied for target, while the sparing of critical organs, including bladder, rectum, femoral heads, urethra, penile bulk and normal tissue outside PTV), were evaluated interms of various dose-volume metrics and integral dose (ID). Meanwhile, the required delivery time and number of monitor units (MUs) during irradiation were measured to estimate the treatment efficiency. The radiobiological indices such as equivalent uniform dose (EUD), tumor control probability (TCP) and the normal tissue complication probability (NTCP) were also analyzed. Results: All dose constraints were achieved by both systems. It showed that the DEGE plans results were closest to the CK plans results in terms of PTV coverage, HI and GI. For EDGE, more conformal dose distribution in the target as well as reduced exposure of critical organs were obtained together with reduction of 91% delivery time and 72% monitor units. EDGE plans also got lower EUD for bladder, rectum, urethra and penile bulk, which associated with reduction of NTCPs. However, higher values of EUD and TCP for tumor were obtained with CK plans. Conclusions: Our study indicated that both systems were capable of producing almost equivalent plan quality and can meet clinical requirements. CyberKnife G4 system has higher target dose while EDGE system has more advantages based on the considerations of normal tissue sparing and delivery efficiency. With abundant clinical experience, CK provides accurate SBRT treatment with high quality. EDGE system also can be considered to be an option for SBRT treatment for localized prostate cancer treatment.

scholarly journals Considerations for the verification of volumetric modulated arc therapy-planned dose distributions

2019 ◽  
Vol 3 ◽  
Author(s):  
Lourens Strauss ◽  
William Shaw
Keyword(s):  
Error Detection ◽  
Volumetric Modulated Arc Therapy ◽  
Standard Of Care ◽  
Target Volume ◽  
Pass Rates ◽  
Dose Distributions ◽  
Dose Volume ◽  
Multi Leaf Collimator ◽  
Arc Therapy ◽  
Verification Systems

Background: Volumetric modulated arc therapy (VMAT) is the standard of care for many clinical indications, but should only be considered with proper technical support and quality assurance (QA) in place. Despite the high accuracy of VMAT systems, errors can be present and adequate verification is required. Dosimetric VMAT verification systems have a broadly similar analysis philosophy. However, many factors influence the analyses and the subsequent QA outcome, based on which the plan will pass or fail.Aim: This study investigated various factors that influence the dosimetric impact and detectability of known linac component deviations on VMAT QA, including geometries, tissue densities, gamma criteria and dose–volume differences.Setting: Universitas Hospital (Annex), Bloemfontein, South Africa.Methods: Deliberate multi-leaf collimator (MLC)-bank offsets were introduced on four different VMAT plans of the prostate, nasopharynx and brain. Measured reference dose sets were compared to measured QA results, using the IBA Dolphin© detector and Compass© software for three dosimetric scenarios. Gamma pass rates over a range of criteria from 1%/2-mm to 4%/4-mm in the total volumes and per structure, as well as dose–volume differences were studied.Results: Gamma tests in the total patient/phantom did not sufficiently detect errors. The calculation media did not influence the QA outcome greatly. However, the detection geometry affected the results. Per structure gamma analyses provided superior error detection, although still missed some clinically relevant differences. The addition of dose–volume analyses highlighted several important errors.Conclusion: Volumetric modulated arc therapy using only total volume gamma analyses can easily overlook clinically relevant errors. The choice of gamma criterion is crucial. Verification with at least a per structure gamma test in combination with dose–volume checks is recommended, especially in small target volume cases.

Dosimetry Analysis of Three Kinds of Radiation Technique for Postoperative Gastric Cancer

2013 ◽  
Vol 641-642 ◽  
pp. 725-731
Author(s):  
Hua Tang ◽  
Ju Dong Luo ◽  
Xu Jing Lu ◽  
Ling Chen ◽  
Yan Ma ◽  
...  
Keyword(s):  
Gastric Cancer ◽  
Spinal Cord ◽  
Treatment Planning ◽  
Statistical Difference ◽  
Intensity Modulated Radiotherapy ◽  
Conformal Radiotherapy ◽  
Target Volume ◽  
Dose Volume Histograms ◽  
Dose Volume ◽  
Better Than

Objective: To compare dose-volume histograms (DVHs) and the dose distribution of three-dimensional conformal radiotherapy(3DCRT),7 fields radiotherapy(7FRT) and intensity-modulated radiotherapy (IMRT) of treatment planning in gastric cancer. Methods: We selected 5 patients with gastric cancer, they were pathologically confirmed stage T3,T4 or N+ gastric cancer. All patients underwent radical gastrectomy. A dosimetry study was carried out on these five patients. For each patient, three kinds of treatment planning were designed with a prescribed dose of 45Gy to 95％of PTV.Many kinds of parameters of these plans in each patient were compared: isodose distributions line、dose-volume histogram(DVH)、V95%、V110%、CI、HI、EI of target volume and the dose of related critical organs. Results: IMRT was superior to 3DCRT and 7F-RT in dose uniformity（p＜0.05）, there was no statistical difference between 3DCRT and 7FRT in CI（p>0.05）.IMRT had better dose conformity than 3DCRT and 7FRT（p＜0.05）, and 3DCRT was better than 7FRT in CI（p＜0.05）.IMRT showed better EI than 3DCRT and 7FRT（p＜0.05）,there was no statistical difference between 3DCRT and 7FRT in EI（p>0.05）.IMRT had advantage at sparing liver compared with 3DCRT and 7FRT（p＜0.05）,7FRT showed better D1/3 of liver than 3DCRT（p＜0.05）,but there was no statistical difference between 3DCRT and 7FRT in Dmean of liver（p>0.05）.IMRT expressed better Dmax of spinal cord than 3DCRT and 7F-RT（p＜0.05）, and 7FRT was better than IMRT in Dmax of spinal cord（p＜0.05）.But the dose received by the both kidneys were not significantly different. Conclusion: IMRT is superior to 3DCRT and 7FRT,and 3DCRT plans showed better CI and Dmax of spinal cord composed to 7FRT,and 7FRT was superior to 3DCRT in D1/3 of liver. IMRT for gastric cancer had physics advantage for clinical application.

scholarly journals Standardization of terminology in stereotactic radiosurgery: Report from the Standardization Committee of the International Leksell Gamma Knife Society

2014 ◽  
Vol 121 (Suppl_2) ◽  
pp. 2-15 ◽  
Author(s):  
Michael Torrens ◽  
Caroline Chung ◽  
Hyun-Tai Chung ◽  
Patrick Hanssens ◽  
David Jaffray ◽  
...  
Keyword(s):  
Stereotactic Radiosurgery ◽  
Gamma Knife ◽  
Organs At Risk ◽  
Gamma Knife Radiosurgery ◽  
Target Volume ◽  
Conformity Index ◽  
Society Meeting ◽  
Coverage Ratio ◽  
Dose Volume ◽  
Volume Limit

ObjectThis report has been prepared to ensure more uniform reporting of Gamma Knife radiosurgery treatment parameters by identifying areas of controversy, confusion, or imprecision in terminology and recommending standards.MethodsSeveral working group discussions supplemented by clarification via email allowed the elaboration of a series of provisional recommendations. These were also discussed in open session at the 16th International Leksell Gamma Knife Society Meeting in Sydney, Australia, in March 2012 and approved subject to certain revisions and the performance of an Internet vote for approval from the whole Society. This ballot was undertaken in September 2012.ResultsThe recommendations in relation to volumes are that Gross Target Volume (GTV) should replace Target Volume (TV); Prescription Isodose Volume (PIV) should generally be used; the term Treated Target Volume (TTV) should replace TVPIV, GTV in PIV, and so forth; and the Volume of Accepted Tolerance Dose (VATD) should be used in place of irradiated volume. For dose prescription and measurement, the prescription dose should be supplemented by the Absorbed Dose, or DV% (for example, D95%), the maximum and minimum dose should be related to a specific tissue volume (for example, D2% or preferably D1 mm3), and the median dose (D50%) should be recorded routinely. The Integral Dose becomes the Total Absorbed Energy (TAE). In the assessment of planning quality, the use of the Target Coverage Ratio (TTV/ GTV), Paddick Conformity Index (PCI = TTV2/[GTV · PIV]), New Conformity Index (NCI = [GTV · PIV]/TTV2), Selectivity Index (TTV/PIV), Homogeneity Index (HI = [D2% –D98%]/D50%), and Gradient Index (GI = PIV0.5/PIV) are reemphasized. In relation to the dose to Organs at Risk (OARs), the emphasis is on dose volume recording of the VATD or the dose/volume limit (for example, V10) in most cases, with the additional use of a Maximum Dose to a small volume (such as 1 mm3) and/or a Point Dose and Mean Point Dose in certain circumstances, particularly when referring to serial organs. The recommendations were accepted by the International Leksell Gamma Knife Society by a vote of 92% to 8%.ConclusionsAn agreed-upon and uniform terminology and subsequent standardization of certain methods and procedures will advance the clinical science of stereotactic radiosurgery.

scholarly journals Stereotactic body radiotherapy (SBRT) reirradiation for recurrent pancreas cancer.

2015 ◽  
Vol 33 (3_suppl) ◽  
pp. 451-451
Author(s):  
Rabia N Dagoglu ◽  
Mark Callery ◽  
James Moser ◽  
Jennifer F. Tseng ◽  
Tara Kent ◽  
...  
Keyword(s):  
Local Control ◽  
Systemic Therapy ◽  
Stereotactic Body Radiotherapy ◽  
Pancreas Cancer ◽  
Target Volume ◽  
Maximum Point ◽  
Prescription Dose ◽  
Locally Recurrent ◽  
Grade Iii

451 Background: After adjuvant or definitive radiation for pancreas cancer, there are limited conventional treatment options for recurrent pancreas cancer. We explored the role of (Stereotactic Body Radiotherapy) SBRT for reirradiation of recurrent pancreas cancer. Methods: Our institutional IRB approved database was retrospectively reviewed. All patients were deemed unresectable and treated with systemic therapy. Fiducial gold markers were used. CT simulation was performed with oral and IV contrast and patients were treated with respiratory motion tracking.The choice of fractionation was based on tumor volume, location of the tumor and prior radiation dose, interval between prior RT, adjacent normal tissue, patients’ performance status and co morbidities. The irradiation dose was prescribed to the isodose line covering at least 95% of the target volume. Maximum point dose to the gastric and duodenal walls was kept at or below prescription dose. Results: This study included 30 patients reirradiated for recurrent pancreas cancer at our center between September 2005 and September 2013. 17 males and 13 females were treated. The median age at the time of reirradiation was 67 years (range 44 to 88 years). Median follow-up was 11 months (4 to 24 months).The median target volume was 41.29cc. The median prescription dose was 25Gy (24-36 Gy) in a median of 5 fractions prescribed to a mean 78% isodose line. The median overall survival was 14 months. The 1 and 2 year local control was 78%. The worst toxicity included 3/30(10%) grade III acute toxicity for pain, bleeding and vomiting. There was 2/30 (7%) Grade III long-term bowel obstructions. Conclusions: Management of locally recurrent pancreatic cancer, particularly after prior radiation therapy, is challenging. We report the utility of SBRT for reirradiation of locally recurrent pancreas cancer after prior radiation, with reasonable local control, modest survival and acceptable toxicity. Future prospective studies are needed to define the role of SBRT reirradiation for local recurrences in the setting of systemic therapy.

Dosimetric and biological comparison of treatment plans between LINAC and robot  systems in stereotactic body radiation therapy for localized prostate cancer

2021 ◽  
Author(s):  
Zhitao Dai ◽  
Lian Zhu ◽  
Tingting Cao ◽  
Aihua Wang ◽  
Xueling Guo ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Radiation Therapy ◽  
Normal Tissue ◽  
Stereotactic Body Radiation Therapy ◽  
Localized Prostate Cancer ◽  
Conformity Index ◽  
Delivery Time ◽  
Plan Quality ◽  
Dose Volume ◽  
Treatment Plans

Abstract Aims The aim of this study was to make a quantitative comparison of plan quality between MLC-based EDGE system and the cone-based CyberKnife system in stereotactic body radiation therapy (SBRT) for patients with localized prostate cancer. Materials and methods Ten patients with prostate volumes ranging from 34.65 to 82.16 cc were used for prostate SBRT. Treatment plans were created for both EDGE and CyberKnife G4 systems using the same dose-volume constraints. Dosimetric indices including Planning Tumor Volume (PTV) coverage, conformity index (CI), new conformity index (nCI), homogeneity index (HI), gradient index (GI) were applied for target, while the sparing of critical organs, including bladder, rectum, femoral heads, urethra, penile bulk and normal tissue outside PTV), were evaluated interms of various dose-volume metrics and integral dose (ID). Meanwhile, the required delivery time and number of monitor units (MUs) during irradiation were measured to estimate the treatment efficiency. The radiobiological indices such as equivalent uniform dose (EUD), tumor control probability (TCP) and the normal tissue complication probability (NTCP) were also analyzed. Results All dose constraints were achieved by both systems. It showed that the DEGE plans results were closest to the CK plans results in terms of PTV coverage, HI and GI. For EDGE, more conformal dose distribution in the target as well as reduced exposure of critical organs were obtained together with reduction of 91% delivery time and 72% monitor units. EDGE plans also got lower EUD for bladder, rectum, urethra and penile bulk, which associated with reduction of NTCPs. However, higher values of EUD and TCP for tumor were obtained with CK plans. Conclusions Our study indicated that both systems were capable of producing almost equivalent plan quality and can meet clinical requirements. CyberKnife G4 system has higher target dose while EDGE system has more advantages based on the considerations of normal tissue sparing and delivery efficiency. With abundant clinical experience, CK provides accurate SBRT treatment with high quality. EDGE system also can be considered to be an option for SBRT treatment for localized prostate cancer treatment.

Sign in / Sign up

Export Citation Format

Share Document