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Niu Y, Rashid A, Lee JM, Carrasquilla M, Conroy DR, Collins BT, Satinsky A, Unger KR, Pang D. Comparative analysis of plan quality and delivery efficiency: ZAP-X vs. CyberKnife for brain metastases treatment. Front Oncol 2024; 14:1333642. [PMID: 38939330 PMCID: PMC11210190 DOI: 10.3389/fonc.2024.1333642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2023] [Accepted: 05/21/2024] [Indexed: 06/29/2024] Open
Abstract
Purpose/Objectives ZAP-X, a novel and dedicated radiosurgery (SRS) system, has recently emerged, while CyberKnife has solidified its position as a versatile solution for SRS and stereotactic body radiation therapy over the past two decades. This study aims to compare the dosimetric performance and delivery efficiency of ZAP-X and CyberKnife in treating brain metastases of varying target sizes, employing circular collimation. Methods and materials Twenty-three patients, encompassing a total of 47 brain metastases, were included in the creation of comparative plans of ZAP-X and CyberKnife for analysis. The comparative plans were generated to achieve identical prescription doses for the targets, while adhering to the same dose constraints for organs at risk (OAR). The prescription isodose percentage was optimized within the range of 97-100% for each plan to ensure effective target-volume coverage. To assess plan quality, indices such as conformity, homogeneity, and gradient (CI, HI, and GI) were computed, along with the reporting of total brain volumes receiving 12Gy and 10Gy. Estimated treatment time and monitor units (MUs) were compared between the two modalities in evaluating delivery efficiency. Results Overall, CyberKnife achieved better CI and HI, while ZAP-X exhibited better GI and a smaller irradiated volume for the normal brain. The superiority of CyberKnife's plan conformity was more pronounced for target size less than 1 cc and greater than 10 cc. Conversely, the advantage of ZAP-X's plan dose gradient was more notable for target sizes under 10 cc. The homogeneity of ZAP-X plans, employing multiple isocenters, displayed a strong correlation with the target's shape and the planner's experience in placing isocenters. Generally, the estimated treatment time was similar between the two modalities, and the delivery efficiency was significantly impacted by the chosen collimation sizes for both modalities. Conclusion This study demonstrates that, within the range of target sizes within the patient cohort, plans generated by ZAP-X and CyberKnife exhibit comparable plan quality and delivery efficiency. At present, with the current platform of the two modalities, CyberKnife outperforms ZAP-X in terms of conformity and homogeneity, while ZAP-X tends to produce plans with a more rapid dose falloff.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Dalong Pang
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, United States
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Kübler J, Wester-Ebbinghaus M, Wenz F, Stieler F, Bathen B, Mai SK, Wolff R, Hänggi D, Blanck O, Giordano FA. Postoperative stereotactic radiosurgery and hypofractionated radiotherapy for brain metastases using Gamma Knife and CyberKnife: a dual-center analysis. J Neurosurg Sci 2024; 68:22-30. [PMID: 32031357 DOI: 10.23736/s0390-5616.20.04830-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2024]
Abstract
BACKGROUND Postoperative stereotactic radiosurgery (SRS) and hypofractionated stereotactic radiotherapy (hFSRT) to tumor cavities is emerging as a new standard of care after resection of brain metastases. Both Gamma Knife (GK) and CyberKnife (CK) are modalities commonly used for stereotactic radiotherapy, but fractional schemes are not consistent. The objective of this study was to evaluate outcomes in patients receiving postoperative stereotactic radiotherapy of resected brain metastases (BM) using different fractionation schedules and modalities in two large centers. METHODS Patients with newly diagnosed BM who underwent postoperative SRS or hFSRT with either GK or CK at two large cancer centers were retrospectively evaluated. We analyzed local control (LC), regional control (RC) and overall survival (OS). RESULTS From April 14th to May 18th, 2020, 79 patients with 81 resection cavities were treated. Forty-seven patients (59.5%) received GK and 32 patients (40.5%) received CK treatment. Fifty-four cavities (66.7%) were treated with hFSRT and 27 (33.3%) with SRS. The most common hFSRT and SRS scheme was 3x10 Gy and 1x16 Gy, respectively. Median OS was 11.7 months with survival rates of 44.7% at 1 year and 18.5% at 2 years. LC was 83.3% after 1 year. Median time to regional progression was 12.0 months with RC rates of 61.1% at 6 months and 41.0% at 12 months. There was no difference in OS, LC or RC between GK and CK treatments or SRS and hFSRT. CONCLUSIONS Both SRS and hFSRT provide high local control rates in resected BM regardless of the applied modality.
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Affiliation(s)
- Jens Kübler
- Department of Radiation Oncology, University Hospital Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Michael Wester-Ebbinghaus
- Department of Radiation Oncology, University Hospital Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | | | - Florian Stieler
- Department of Radiation Oncology, University Hospital Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Bastian Bathen
- Saphir Radiosurgery Center Frankfurt, Frankfurt am Main, Germany
- Department of Radiation Oncology, University Hospital Frankfurt, Frankfurt am Main, Germany
| | - Sabine K Mai
- Department of Radiation Oncology, University Hospital Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Robert Wolff
- Saphir Radiosurgery Center Frankfurt, Frankfurt am Main, Germany
- Department of Neurosurgery, University Hospital Frankfurt, Frankfurt am Main, Germany
| | - Daniel Hänggi
- Department of Neurosurgery, University Hospital Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Oliver Blanck
- Saphir Radiosurgery Center Frankfurt, Frankfurt am Main, Germany
- Department of Radiation Oncology, University Medical Center Schleswig-Holstein, Kiel, Germany
| | - Frank A Giordano
- Department of Radiation Oncology, University Hospital Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany -
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Etter E, Bosse B, Wang YP, Hiniker S, Oh J. Successful treatment of orbital Langerhans cell histiocytosis with stereotactic radiosurgery: A case report and literature review. Clin Case Rep 2023; 11:e7506. [PMID: 37346879 PMCID: PMC10279942 DOI: 10.1002/ccr3.7506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 05/16/2023] [Accepted: 05/23/2023] [Indexed: 06/23/2023] Open
Abstract
Langerhans cell histiocytosis (LCH) is a rare inflammatory myeloid neoplasm arising from the proliferation of pathologic Langerhans cells. LCH has a spectrum of presentations predominantly affecting male pediatric patients. As LCH is a relatively uncommon diagnosis, there is no standard of care for treatment of the disease and treatment is based largely on clinical judgment, lesion characteristics, and symptoms at presentation. Here we present a case of unifocal, isolated orbital LCH in a 19-year-old young man treated initially with surgical resection. Follow-up imaging 2 months later demonstrated significant regrowth of the mass and no other sites of disease. The recurrent orbital disease was treated with stereotactic radiosurgery (SRS) to 7 Gy in one fraction. Near complete resolution of the mass was achieved with no recurrence after 1.5 years of follow-up. SRS for treatment of orbital LCH is a novel treatment not previously described in the literature which may provide benefit in select cases.
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Affiliation(s)
- Emily Etter
- University of Nevada Reno School of MedicineRenoNevadaUSA
| | - Benjamin Bosse
- University of Nevada Reno School of MedicineRenoNevadaUSA
| | - Yi Peng Wang
- Department of Radiation OncologyStanford University School of MedicineStanfordCaliforniaUSA
| | - Susan Hiniker
- Department of Radiation OncologyStanford University School of MedicineStanfordCaliforniaUSA
| | - Justin Oh
- Department of Radiation OncologyStanford University School of MedicineStanfordCaliforniaUSA
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4
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Ianiro A, Infusino E, D’Andrea M, Marucci L, Farneti A, Sperati F, Cassano B, Ungania S, Soriani A. Multiple Brain Metastases Radiosurgery with CyberKnife Device: Dosimetric Comparison between Fixed/Iris and Multileaf Collimator Plans. J Med Phys 2023; 48:120-128. [PMID: 37576098 PMCID: PMC10419749 DOI: 10.4103/jmp.jmp_82_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 03/20/2023] [Accepted: 03/23/2023] [Indexed: 08/15/2023] Open
Abstract
Purpose In our institution, stereotactic radiosurgery of multiple brain metastases is performed with the CyberKnife® (CK) device, using fixed/Iris collimators. In this study, nineteen fixed/Iris plans were recalculated with the multileaf collimator (MLC), to assess if it is possible to produce plans with comparable dosimetric overall quality. Materials and Methods For consistent comparisons, MLC plans were re-optimized and re-normalized in order to achieve the same minimum dose for the total planning target volume (PTVtot). Conformation number (CN), homogeneity index (HI) and dose gradient index (DGI) metrics were evaluated. The dose to the brain was evaluated as the volume receiving 12 Gy (V12) and as the integral dose (ID). The normal tissue complication probability (NTCP) for brain radionecrosis was calculated as a function of V12. Results The reoptimized plans were reviewed by the radiation oncologist and were found clinically acceptable according to the The American Association of Physicists in Medicine (AAPM) Task Group-101 protocol. However, fixed/Iris plans provided significantly higher CN (+8.6%), HI (+2.2%), and DGI (+44.0%) values, and significantly lower ID values (-35.9%). For PTVtot less than the median value of 2.58cc, fixed/Iris plans provided significantly lower NTCP values. On the other side, MLC plans provided significantly lower treatment times (-18.4%), number of monitor units (-33.3%), beams (-46.0%) and nodes (-21.3%). Conclusions CK-MLC plans for the stereotactic treatment of brain multi metastases could provide an important advantage in terms of treatment duration. However, to contain the increased risk for brain radionecrosis, it could be useful to calculate MLC plans only for patients with large PTVtot.
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Affiliation(s)
- Anna Ianiro
- Department of Medical Physics, IRCCS Regina Elena National Cancer Institute – IFO, Rome, Italy
| | - Erminia Infusino
- Department of Medical Physics, IRCCS Regina Elena National Cancer Institute – IFO, Rome, Italy
| | - Marco D’Andrea
- Department of Medical Physics, IRCCS Regina Elena National Cancer Institute – IFO, Rome, Italy
| | - Laura Marucci
- Department of Radiation Oncology, IRCCS Regina Elena National Cancer Institute – IFO, Rome, Italy
| | - Alessia Farneti
- Department of Radiation Oncology, IRCCS Regina Elena National Cancer Institute – IFO, Rome, Italy
| | - Francesca Sperati
- Department of Biostatistics and Bioinformatics, Clinical Trial Center, IRCCS San Gallicano Dermatological Institute – IFO, Rome, Italy
| | - Bartolomeo Cassano
- Department of Medical Physics, IRCCS Regina Elena National Cancer Institute – IFO, Rome, Italy
| | - Sara Ungania
- Department of Medical Physics, IRCCS Regina Elena National Cancer Institute – IFO, Rome, Italy
| | - Antonella Soriani
- Department of Medical Physics, IRCCS Regina Elena National Cancer Institute – IFO, Rome, Italy
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Takizawa T, Tanabe S, Nakano H, Utsunomiya S, Sakai M, Maruyama K, Takeuchi S, Nakano T, Ohta A, Kaidu M, Ishikawa H, Onda K. The impact of target positioning error and tumor size on radiobiological parameters in robotic stereotactic radiosurgery for metastatic brain tumors. Radiol Phys Technol 2022; 15:135-146. [DOI: 10.1007/s12194-022-00655-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 02/25/2022] [Accepted: 02/26/2022] [Indexed: 12/01/2022]
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Loo M, Clavier JB, Attal Khalifa J, Moyal E, Khalifa J. Dose-Response Effect and Dose-Toxicity in Stereotactic Radiotherapy for Brain Metastases: A Review. Cancers (Basel) 2021; 13:cancers13236086. [PMID: 34885193 PMCID: PMC8657210 DOI: 10.3390/cancers13236086] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 11/26/2021] [Accepted: 11/29/2021] [Indexed: 11/29/2022] Open
Abstract
Simple Summary Brain metastases are one of the most frequent complications for cancer patients. Stereotactic radiosurgery is considered a cornerstone treatment for patients with limited brain metastases and the ideal dose and fractionation schedule still remain unknown. The aim of this literature review is to discuss the dose-effect relation in brain metastases treated by stereotactic radiosurgery, accounting for fractionation and technical considerations. Abstract For more than two decades, stereotactic radiosurgery has been considered a cornerstone treatment for patients with limited brain metastases. Historically, radiosurgery in a single fraction has been the standard of care but recent technical advances have also enabled the delivery of hypofractionated stereotactic radiotherapy for dedicated situations. Only few studies have investigated the efficacy and toxicity profile of different hypofractionated schedules but, to date, the ideal dose and fractionation schedule still remains unknown. Moreover, the linear-quadratic model is being debated regarding high dose per fraction. Recent studies shown the radiation schedule is a critical factor in the immunomodulatory responses. The aim of this literature review was to discuss the dose–effect relation in brain metastases treated by stereotactic radiosurgery accounting for fractionation and technical considerations. Efficacy and toxicity data were analyzed in the light of recent published data. Only retrospective and heterogeneous data were available. We attempted to present the relevant data with caution. A BED10 of 40 to 50 Gy seems associated with a 12-month local control rate >70%. A BED10 of 50 to 60 Gy seems to achieve a 12-month local control rate at least of 80% at 12 months. In the brain metastases radiosurgery series, for single-fraction schedule, a V12 Gy < 5 to 10 cc was associated to 7.1–22.5% radionecrosis rate. For three-fractions schedule, V18 Gy < 26–30 cc, V21 Gy < 21 cc and V23 Gy < 5–7 cc were associated with about 0–14% radionecrosis rate. For five-fractions schedule, V30 Gy < 10–30 cc, V 28.8 Gy < 3–7 cc and V25 Gy < 16 cc were associated with about 2–14% symptomatic radionecrosis rate. There are still no prospective trials comparing radiosurgery to fractionated stereotactic irradiation.
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Affiliation(s)
- Maxime Loo
- Radiotherapy Department, University Cancer Institute of Toulouse—Oncopôle, 31100 Toulouse, France; (J.A.K.); (E.M.); (J.K.)
- Correspondence:
| | - Jean-Baptiste Clavier
- Radiotherapy Department, Strasbourg Europe Cancer Institute (ICANS), 67033 Strasbourg, France;
| | - Justine Attal Khalifa
- Radiotherapy Department, University Cancer Institute of Toulouse—Oncopôle, 31100 Toulouse, France; (J.A.K.); (E.M.); (J.K.)
| | - Elisabeth Moyal
- Radiotherapy Department, University Cancer Institute of Toulouse—Oncopôle, 31100 Toulouse, France; (J.A.K.); (E.M.); (J.K.)
| | - Jonathan Khalifa
- Radiotherapy Department, University Cancer Institute of Toulouse—Oncopôle, 31100 Toulouse, France; (J.A.K.); (E.M.); (J.K.)
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Zhou H, Wu T, Zhu X, Li Y. Re-irradiation of multiple brain metastases using CyberKnife stereotactic radiotherapy: Case report. Medicine (Baltimore) 2021; 100:e27543. [PMID: 34731155 PMCID: PMC8519193 DOI: 10.1097/md.0000000000027543] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Accepted: 10/01/2021] [Indexed: 01/05/2023] Open
Abstract
INTRODUCTION Brain metastasis (BM) is the commonest adult intracranial malignancy and many patients with brain metastases require two course radiotherapy. Re-irradiation is frequently performed in Radiotherapy (RT) departments for multiple brain metastases. PATIENT CONCERNS We present a case of a 55-year-old male patient suffering from brain metastases, who had previously received whole-brain radiotherapy (WBRT) and first CyberKnife Stereotactic Radiotherapy (CKSRT) for metastases, presented with a recurrence of metastasis and new lesions in the brain. DIAGNOSES An enhanced computed tomography (CT) scan of the brain revealed abnormalities with double-dosing of intravenous contrast that identified >10 lesions scattered in the whole brain. INTERVENTIONS Re-irradiation was performed using CKSRT. The patient was treated with 30 Gy in 5 fractions for new lesions and 25 Gy in 5 fractions for lesion that were locally recurrent and close to brainstem lesions. OUTCOME The lesions were well-controlled, and the headache of the patient was significantly relieved one month after radiotherapy. The total survival time of the patients was 17 months from the beginning of the Cyberknife treatment. CONCLUSION The present case report demonstrates that CyberKnife therapy plays a significant role in the repeated radiotherapy for multiple metastatic brain tumors. CKSRT can be used as a salvage method in recurrent multiple brain metastases.
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Affiliation(s)
- Han Zhou
- School of Electronic Science and Engineering, Nanjing University, Nanjing, China
- Department of Radiation Oncology The Fourth Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China
| | - Tiancong Wu
- Department of Radiation Oncology, Jinling hospital, Jiangsu, China
| | - Xixu Zhu
- Department of Radiation Oncology, Jinling hospital, Jiangsu, China
| | - Yikun Li
- Department of Radiation Oncology, Jinling hospital, Jiangsu, China
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8
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Greve T, Ehret F, Hofmann T, Thorsteinsdottir J, Dorn F, Švigelj V, Resman-Gašperšič A, Tonn JC, Schichor C, Muacevic A. Magnetic Resonance Imaging-Based Robotic Radiosurgery of Arteriovenous Malformations. Front Oncol 2021; 10:608750. [PMID: 33767974 PMCID: PMC7986716 DOI: 10.3389/fonc.2020.608750] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 12/21/2020] [Indexed: 11/19/2022] Open
Abstract
Objective CyberKnife offers CT- and MRI-based treatment planning without the need for stereotactically acquired DSA. The literature on CyberKnife treatment of cerebral AVMs is sparse. Here, a large series focusing on cerebral AVMs treated by the frameless CyberKnife stereotactic radiosurgery (SRS) system was analyzed. Methods In this retrospective study, patients with cerebral AVMs treated by CyberKnife SRS between 2005 and 2019 were included. Planning was MRI- and CT-based. Conventional DSA was not coregistered to the MRI and CT scans used for treatment planning and was only used as an adjunct. Obliteration dynamics and clinical outcome were analyzed. Results 215 patients were included. 53.0% received SRS as first treatment; the rest underwent previous surgery, embolization, SRS, or a combination. Most AVMs were classified as Spetzler-Martin grade I to III (54.9%). Hemorrhage before treatment occurred in 46.0%. Patients suffered from headache (28.8%), and seizures (14.0%) in the majority of cases. The median SRS dose was 18 Gy and the median target volume was 2.4 cm³. New neurological deficits occurred in 5.1% after SRS, with all but one patient recovering. The yearly post-SRS hemorrhage incidence was 1.3%. In 152 patients who were followed-up for at least three years, 47.4% showed complete AVM obliteration within this period. Cox regression analysis revealed Spetzler-Martin grade (P = 0.006) to be the only independent predictor of complete obliteration. Conclusions Although data on radiotherapy of AVMs is available, this is one of the largest series, focusing exclusively on CyberKnife treatment. Safety and efficacy compared favorably to frame-based systems. Non-invasive treatment planning, with a frameless SRS robotic system might provide higher patient comfort, a less invasive treatment option, and lower radiation exposure.
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Affiliation(s)
- Tobias Greve
- Department of Neurosurgery, University Hospital, LMU Munich, Munich, Germany
| | - Felix Ehret
- European Cyberknife Center Munich-Grosshadern, Munich, Germany
| | - Theresa Hofmann
- European Cyberknife Center Munich-Grosshadern, Munich, Germany
| | | | - Franziska Dorn
- Institute of Neuroradiology, University Hospital, LMU Munich, Munich, Germany
| | - Viktor Švigelj
- Division of Neurology, University Medical Center Ljubljana, Ljubljana, Slovenia
| | | | | | - Christian Schichor
- Department of Neurosurgery, University Hospital, LMU Munich, Munich, Germany
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Boczkowski A, Kelly P, Meeks SL, Erhart K, Bova FJ, Willoughby TR. Proton vs Hyperarc™ radiosurgery: A planning comparison. J Appl Clin Med Phys 2020; 21:96-108. [PMID: 33151014 PMCID: PMC7769415 DOI: 10.1002/acm2.13075] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 09/24/2020] [Accepted: 09/29/2020] [Indexed: 11/29/2022] Open
Abstract
For many patients, stereotactic radiosurgery (SRS) offers a minimally invasive, curative option when surgical techniques are not possible. To date, the literature supporting the efficacy and safety of SRS treatment techniques uses photon beams. However, with the number of proton therapy facilities exponentially growing and the favorable physical properties of proton beam radiation therapy, there is an opportunity to develop proton therapy techniques for SRS. The goal of this paper is to determine the ability of clinical proton treatment planning systems to model small field dosimetry accurately and to compare various planning metrics used to evaluate photon SRS to determine the optimum beam configurations and settings for proton SRS (PSRS) treatment plans. Once established, these plan settings were used to perform a planning comparison on a variety of different SRS cases and compare SRS metrics between the PSRS plans and HyperArc™ (VMAT) SRS plans.
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Affiliation(s)
- A. Boczkowski
- Department of NeurosurgeryUniversity of FloridaGainesvilleFLUSA
| | - P. Kelly
- UF Health Cancer Center–Orlando HealthOrlandoFLUSA
| | - S. L. Meeks
- UF Health Cancer Center–Orlando HealthOrlandoFLUSA
| | | | - F. J. Bova
- Department of NeurosurgeryUniversity of FloridaGainesvilleFLUSA
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Han EY, Wang H, Luo D, Li J, Wang X. Dosimetric comparison of fractionated radiosurgery plans using frameless Gamma Knife ICON and CyberKnife systems with linear accelerator–based radiosurgery plans for multiple large brain metastases. J Neurosurg 2020; 132:1473-1479. [DOI: 10.3171/2019.1.jns182769] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 01/14/2019] [Indexed: 11/06/2022]
Abstract
OBJECTIVEFor patients with multiple large brain metastases with at least 1 target volume larger than 10 cm3, multifractionated stereotactic radiosurgery (MF-SRS) has commonly been delivered with a linear accelerator (LINAC). Recent advances of Gamma Knife (GK) units with kilovolt cone-beam CT and CyberKnife (CK) units with multileaf collimators also make them attractive choices. The purpose of this study was to compare the dosimetry of MF-SRS plans deliverable on GK, CK, and LINAC and to discuss related clinical issues.METHODSTen patients with 2 or more large brain metastases who had been treated with MF-SRS on LINAC were identified. The median planning target volume was 18.31 cm3 (mean 21.31 cm3, range 3.42–49.97 cm3), and the median prescribed dose was 27.0 Gy (mean 26.7 Gy, range 21–30 Gy), administered in 3 to 5 fractions. Clinical LINAC treatment plans were generated using inverse planning with intensity modulation on a Pinnacle treatment planning system (version 9.10) for the Varian TrueBeam STx system. GK and CK planning were retrospectively performed using Leksell GammaPlan version 10.1 and Accuray Precision version 1.1.0.0 for the CK M6 system. Tumor coverage, Paddick conformity index (CI), gradient index (GI), and normal brain tissue receiving 4, 12, and 20 Gy were used to compare plan quality. Net beam-on time and approximate planning time were also collected for all cases.RESULTSPlans from all 3 modalities satisfied clinical requirements in target coverage and normal tissue sparing. The mean CI was comparable (0.79, 0.78, and 0.76) for the GK, CK, and LINAC plans. The mean GI was 3.1 for both the GK and the CK plans, whereas the mean GI of the LINAC plans was 4.1. The lower GI of the GK and CK plans would have resulted in significantly lower normal brain volumes receiving a medium or high dose. On average, GK and CK plans spared the normal brain volume receiving at least 12 Gy and 20 Gy by approximately 20% in comparison with the LINAC plans. However, the mean beam-on time of GK (∼ 64 minutes assuming a dose rate of 2.5 Gy/minute) plans was significantly longer than that of CK (∼ 31 minutes) or LINAC (∼ 4 minutes) plans.CONCLUSIONSAll 3 modalities are capable of treating multiple large brain lesions with MF-SRS. GK has the most flexible workflow and excellent dosimetry, but could be limited by the treatment time. CK has dosimetry comparable to that of GK with a consistent treatment time of approximately 30 minutes. LINAC has a much shorter treatment time, but residual rotational error could be a concern.
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Affiliation(s)
| | - He Wang
- Departments of 1Radiation Physics and
| | | | - Jing Li
- 2Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Xin Wang
- Departments of 1Radiation Physics and
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11
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Yang J, Liu G, Liu HY, Nie X, Yang ZY, Han J, Zhang S, Liang ZW. Influence of CyberKnife Prescription Isodose Line on the Discrepancy of Dose Results Calculated by the Ray Tracing and Monte Carlo Algorithms for Head and Lung Plans: A Phantom Study. Curr Med Sci 2020; 40:301-306. [PMID: 32337689 DOI: 10.1007/s11596-020-2177-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 03/24/2020] [Indexed: 11/29/2022]
Abstract
Incorporation of the Monte Carlo (MC) algorithm in optimizing CyberKnife (CK) plans is cumbersome, and early models unconfgured MC calculations, therefore, this study investigated algorithm-based dose calculation discrepancies by selecting different prescription isodose lines (PIDLs) in head and lung CK plans. CK plans were based on anthropomorphic phantoms. Four shells were set at 2-60 mm from the target, and the constraint doses were adjusted according to the design strategy. After optimization, 30%-90% PIDL plans were generated by ray tracing (RT). In the evaluation module, CK plans were recalculated using the MC algorithm. Therefore, the dosimetric parameters of different PIDL plans based on the RT and MC algorithms were obtained and analyzed. The discrepancies (mean±SD) were 3.72%±0.31%, 3.40%±0.11%, 3.47%±0.32%, 0.17%±0.11%, 0.64%±3.60%, 7.73%±1.60%, 14.62%±3.21% and 10.10%±1.57% for D1%, D(mean), D98% and coverage of the PTV, DGI, V5, V3 and V1 in the head plans and -6.32%±1.15%, -13.46%±0.98%, -20.63%±2.25%, -34.78%±25.03%, 122.48%±175.60%, -12.92%±5.41%, 3.19%±4.67% and 7.13%±1.56% in the lung plans, respectively. The following parameters were signifcantly correlated with PIDL: dD98% at the 0.05 level and dDGI, dV5 and dV3 at the 0.01 level for the head plans; dD98% at the 0.05 level and dD1%, dD(mean), dCoverage, dDGI, dV5 and dV3 at the 0.01 level for the lung plans. RT may be used to calculate the dose in CK head plans, but when the dose of organs at risk is close to the limit, it is necessary to refer to the MC results or to further optimize the CK plan to reduce the dose. For lung plans, the MC algorithm is recommended. For early models without the MC algorithm, a lower PIDL plan is recommended; otherwise, a large PIDL plan risks serious underdosage in the target area.
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Affiliation(s)
- Jing Yang
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430023, China
| | - Gang Liu
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430023, China
| | - Hong-Yuan Liu
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430023, China
| | - Xin Nie
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430023, China
| | - Zhi-Yong Yang
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430023, China
| | - Jun Han
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430023, China
| | - Sheng Zhang
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430023, China
| | - Zhi-Wen Liang
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430023, China.
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12
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Novel inverse planning optimization algorithm for robotic radiosurgery: First clinical implementation and dosimetric evaluation. Phys Med 2019; 64:230-237. [DOI: 10.1016/j.ejmp.2019.07.020] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 07/23/2019] [Accepted: 07/25/2019] [Indexed: 12/31/2022] Open
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13
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Han EY, Kim GY, Rebueno N, Yeboa DN, Briere TM. End-to-end testing of automatic plan optimization using RayStation scripting for hypofractionated multimetastatic brain stereotactic radiosurgery. Med Dosim 2019; 44:e44-e50. [PMID: 30655170 DOI: 10.1016/j.meddos.2018.12.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 11/16/2018] [Accepted: 12/27/2018] [Indexed: 11/29/2022]
Abstract
For external beam stereotactic radiosurgery of multiple brain metastatic lesions, it is difficult to select optimal treatment isocenters because the orientation and volume of each planning target volume (PTV) and its proximity to critical structures are unique for each patient. The RayStation treatment planning system offers Python-based scripting to optimize the placement of the treatment isocenter by comparing scenario-based plans. This can improve the plan quality by reducing the dose to the normal brain and increasing planning efficiency. The purpose of the current study was to compare the isocenter-optimized plans generated by RayStation with clinical plans created by the Pinnacle treatment planning system and to validate the RayStation treatment planning and delivery with end-to-end testing. Ten patient plans were automatically regenerated using the script in RayStation. For each patient, 4 plans with 4 different types of isocenters were generated: (1) 2 separate isocenters at the PTV centroids, (2) a single isocenter at the mid-point of 2 centroids, (3) a single isocenter at PTV1, and (4) a single isocenter at PTV2. The best plans were compared with paired Pinnacle plans using plan quality parameters, including normal brain volume excluding PTVs receiving 4 Gy (V4Gy), normal brain volume excluding PTVs receiving 12 Gy (V12Gy), maximum dose to the brainstem, homogeneity index, conformity indices, gradient index of each PTV, and monitor units per fraction. All plans were verified with a cylindrical quality assurance phantom, and end-to-end testing was performed with an anthropomorphic head phantom with a radiochromic film. The script was executed within 5-6 minutes to generate 4 scenario-based automatic plans. The homogeneity index and conformity indices showed small but statistically significant improvement with the RayStation plans. The gradient index (3.9 ± 0.9 for Pinnacle and 3.5 ± 0.6 for RayStation, p = 0.04) was also more favorable in the RayStation plans. V12Gy was significantly reduced by 13% and V4Gy was reduced by 5%. The total monitor units per fraction was significantly reduced by 20% for the RayStation plans. Plan optimization time using RayStation was reduced by 64%. The measured doses at each PTV centroid agreed within 3%, and all RayStation plans passed quality assurance verification tests. Scenario-based automatic plan generation using Python scripting helps identify an optimal treatment isocenter to reduce the dose to the normal brain and improve planning efficiency. RayStation plans provided better plan quality, especially lower doses to the normal brain, than Pinnacle plans. Thus, RayStation is a suitable planning modality for hypofractionated stereotactic radiosurgery for multiple brain metastases.
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Affiliation(s)
- Eun Young Han
- Department of Radiation Physics, Unit 94, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| | - Gwe-Ya Kim
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, CA 92093, USA
| | - Neal Rebueno
- Department of Radiation Physics, Unit 94, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Debra N Yeboa
- Department of Radiation Oncology, Unit 97, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Tina M Briere
- Department of Radiation Physics, Unit 94, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
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14
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Clinical Evaluation of Shot-Within-Shot Optimization for Gamma Knife Radiosurgery Planning and Delivery. World Neurosurg 2018; 123:e218-e227. [PMID: 30481630 DOI: 10.1016/j.wneu.2018.11.140] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 11/14/2018] [Accepted: 11/16/2018] [Indexed: 11/22/2022]
Abstract
OBJECTIVE Shot-within-shot (SWS) optimization is a new planning technique that relies on various combinations of shot weighting and prescription isodose line (IDL) to reduce beam-on time. The method differs from other planning techniques that incorporate mixed collimation, multiple stereotactic coordinates, and traditionally low prescription IDLs (<60%). In this work, we evaluate the percentage of brain metastasis for which the method can be applied, the magnitude of the resultant time savings, and the possible tradeoffs in plan quality. METHODS A retrospective analysis was performed on 75 patients treated for 241 metastatic lesions in the brain. For each lesion, the original planning metrics related to target coverage, conformity, gradient, and beam-on time were recorded. A subset of lesions were selected for replanning using the SWS technique based on size, shape, and proximity to critical structures. Two replans were done, a reference plan was prescribed at the 50% IDL, and an optimized plan was prescribed at an IDL typically >50%. Planning metrics were then compared among the original plan and the 2 replans. RESULTS More than a third (39%) of the brain metastases were eligible for the SWS technique. For these lesions, the differences between the original plan and reference SWS plan were as follows: ΔV12Gy < 0.5 cc in 93% of cases, ΔV12Gy < 0.5 cc in 100% of cases, Δselectivity < 0.1 in 79% of cases. Negligible differences were seen between the 2 replans in terms of Δselectivity and ΔV12Gy; ΔGI < 5% in 99% of cases. After optimization, beam-on time was reduced by 25%-30% in approximately 40%-50% of eligible lesions when compared with the reference SWS plan (ΔTmax = 42%). In comparison with the original plan, beam-on time was reduced even further, ΔT > 50% in 20% of cases (ΔTmax = 70%). CONCLUSIONS This work demonstrates clinically that optimization using the shot-within-shot technique can reduce beam-on time without degrading treatment plan quality.
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15
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Dahan O, Guichard F, Galland-Girodet S, Monteil P, Guichard P, Mollier O. [Interest of robotic stereotactic radiosurgery in the management of brain metastases: Results of a retrospective, single center analysis]. Neurochirurgie 2018; 64:415-421. [PMID: 30424956 DOI: 10.1016/j.neuchi.2018.05.180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 04/26/2018] [Accepted: 05/20/2018] [Indexed: 10/27/2022]
Abstract
PURPOSE The management of malignant brain metastases becomes a main issue for the treatment of patients, because of the survival extension related to the improvement in systemic treatments. Robotic stereotactic radiosurgery (RSR) is a new approach in this indication. The purpose of this analysis was to define the efficacy of RSR, in order to determine prognostic factors of survival and factors of response. PATIENTS AND METHODS It was a retrospective, single center (polyclinique de Bordeaux Nord Aquitaine) analysis performed from 2012 to 2015, involving patients with malignant brain metastases treated by RSR using the Cyberknife® technique. We analyzed the following parameters: response to RSR, prognostic and predictive factors of response, and survival. RESULTS A total of 72 RSRs were performed among 55 analyzed patients; 62 treatments were assessable with a median follow-up of 9.4 months. The main delivered dose on the 80%-isodose was 20Gy. A complete response was achieved in 40.3% of patients (stability or regression=83.9%). The overall survival was 13 months. The risk of failure was significantly correlated with the increase in metastasis size and non-adenocarcinoma histology. A performance status<2 was the main prognostic factor of survival. CONCLUSIONS The RSR allowed treating 3 to 5 brain metastases, avoiding an entire brain irradiation, and maintaining survival and quality of life.
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Affiliation(s)
- O Dahan
- Service d'oncoradiothérapie, polyclinique de Bordeaux Nord, 15, rue Claude-Boucher, 33000 Bordeaux, France.
| | - F Guichard
- Service d'oncoradiothérapie, polyclinique de Bordeaux Nord, 15, rue Claude-Boucher, 33000 Bordeaux, France
| | - S Galland-Girodet
- Service d'oncoradiothérapie, polyclinique de Bordeaux Nord, 15, rue Claude-Boucher, 33000 Bordeaux, France
| | - P Monteil
- Service de Neurochirurgie, centre hospitalier universitaire de Bordeaux, place Amélie-Raba-Léon, 33000 Bordeaux, France
| | - P Guichard
- Service d'oncoradiothérapie, polyclinique de Bordeaux Nord, 15, rue Claude-Boucher, 33000 Bordeaux, France
| | - O Mollier
- Service de Neurochirurgie, centre hospitalier universitaire de Bordeaux, place Amélie-Raba-Léon, 33000 Bordeaux, France
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16
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Yoon KJ, Cho B, Kwak JW, Lee D, Kwon DH, Ahn SD, Lee SW, Kim CJ, Roh SW, Cho YH. Cyberknife Dosimetric Planning Using a Dose-Limiting Shell Method for Brain Metastases. J Korean Neurosurg Soc 2018; 61:753-760. [PMID: 30396248 PMCID: PMC6280060 DOI: 10.3340/jkns.2018.0075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 08/04/2018] [Indexed: 11/30/2022] Open
Abstract
Objective We investigated the effect of optimization in dose-limiting shell method on the dosimetric quality of CyberKnife (CK) plans in treating brain metastases (BMs).
Methods We selected 19 BMs previously treated using CK between 2014 and 2015. The original CK plans (CKoriginal) had been produced using 1 to 3 dose-limiting shells : one at the prescription isodose level (PIDL) for dose conformity and the others at lowisodose levels (10–30% of prescription dose) for dose spillage. In each case, a modified CK plan (CKmodified) was generated using 5 dose-limiting shells : one at the PIDL, another at intermediate isodose level (50% of prescription dose) for steeper dose fall-off, and the others at low-isodose levels, with an optimized shell-dilation size based on our experience. A Gamma Knife (GK) plan was also produced using the original contour set. Thus, three data sets of dosimetric parameters were generated and compared.
Results There were no differences in the conformity indices among the CKoriginal, CKmodified, and GK plans (mean 1.22, 1.18, and 1.24, respectively; p=0.079) and tumor coverage (mean 99.5%, 99.5%, and 99.4%, respectively; p=0.177), whereas the CKmodified plans produced significantly smaller normal tissue volumes receiving 50% of prescription dose than those produced by the CKoriginal plans (p<0.001), with no statistical differences in those volumes compared with GK plans (p=0.345).
Conclusion These results indicate that significantly steeper dose fall-off is able to be achieved in the CK system by optimizing the shell function while maintaining high conformity of dose to tumor.
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Affiliation(s)
- Kyoung Jun Yoon
- Radiosurgery Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Byungchul Cho
- Department of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Jung Won Kwak
- Department of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Doheui Lee
- Radiosurgery Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Do Hoon Kwon
- Department of Neurosurgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Seung Do Ahn
- Department of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Sang-Wook Lee
- Department of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Chang Jin Kim
- Department of Neurosurgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Sung Woo Roh
- Department of Neurosurgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Young Hyun Cho
- Department of Neurosurgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
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17
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Dosimetric analysis of Tomotherapy-based intracranial stereotactic radiosurgery of brain metastasis. Phys Med 2018; 52:48-55. [DOI: 10.1016/j.ejmp.2018.06.632] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 05/18/2018] [Accepted: 06/15/2018] [Indexed: 11/17/2022] Open
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18
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Johnson PB, Monterroso MI, Yang F, Mellon E. Optimization of the prescription isodose line for Gamma Knife radiosurgery using the shot within shot technique. Radiat Oncol 2017; 12:187. [PMID: 29178912 PMCID: PMC5702131 DOI: 10.1186/s13014-017-0919-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 10/02/2017] [Indexed: 11/18/2022] Open
Abstract
Background This work explores how the choice of prescription isodose line (IDL) affects the dose gradient, target coverage, and treatment time for Gamma Knife radiosurgery when a smaller shot is encompassed within a larger shot at the same stereotactic coordinates (shot within shot technique). Methods Beam profiles for the 4, 8, and 16 mm collimator settings were extracted from the treatment planning system and characterized using Gaussian fits. The characterized data were used to create over 10,000 shot within shot configurations by systematically changing collimator weighting and choice of prescription IDL. Each configuration was quantified in terms of the dose gradient, target coverage, and beam-on time. By analyzing these configurations, it was found that there are regions of overlap in target size where a higher prescription IDL provides equivalent dose fall-off to a plan prescribed at the 50% IDL. Furthermore, the data indicate that treatment times within these regions can be reduced by up to 40%. An optimization strategy was devised to realize these gains. The strategy was tested for seven patients treated for 1–4 brain metastases (20 lesions total). Results For a single collimator setting, the gradient in the axial plane was steepest when prescribed to the 56–63% (4 mm), 62–70% (8 mm), and 77–84% (16 mm) IDL, respectively. Through utilization of the optimization technique, beam-on time was reduced by more than 15% in 16/20 lesions. The volume of normal brain receiving 12 Gy or above also decreased in many cases, and in only one instance increased by more than 0.5 cm3. Conclusions This work demonstrates that IDL optimization using the shot within shot technique can reduce treatment times without degrading treatment plan quality. Electronic supplementary material The online version of this article (10.1186/s13014-017-0919-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Perry B Johnson
- Radiation Oncology / Biomedical Engineering, University of Miami, 1475 NW 12th Ave, Miami, FL, 33136, USA.
| | - Maria I Monterroso
- Radiation Oncology, University of Miami, 1475 NW 12th Ave, Miami, FL, 33136, USA
| | - Fei Yang
- Radiation Oncology, University of Miami, 1475 NW 12th Ave, Miami, FL, 33136, USA
| | - Eric Mellon
- Radiation Oncology, University of Miami, 1475 NW 12th Ave, Miami, FL, 33136, USA
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Xu Q, Fan J, Grimm J, LaCouture T, Asbell S, Park JH, Kubicek G. The dosimetric impact of the prescription isodose line (IDL) on the quality of robotic stereotactic radiosurgery (SRS) plans. Med Phys 2017; 44:6159-6165. [DOI: 10.1002/mp.12630] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 09/13/2017] [Accepted: 10/09/2017] [Indexed: 01/11/2023] Open
Affiliation(s)
- Qianyi Xu
- Department of Radiation Oncology; MD Anderson Cancer Center at Cooper; Camden NJ 08103 USA
| | - Jiajin Fan
- Department of Radiation Oncology; Fox Chase Cancer Center; Philadelphia PA 19111 USA
| | - Jimm Grimm
- Department of Radiation Oncology; Johns Hopkins University; Baltimore MD 21231 USA
| | - Tamara LaCouture
- Department of Radiation Oncology; Kennedy Health System; Sewell NJ 08080 USA
| | - Sucha Asbell
- Department of Radiation Oncology; MD Anderson Cancer Center at Cooper; Camden NJ 08103 USA
| | - Joo Han Park
- Department of Radiation Oncology; MD Anderson Cancer Center at Cooper; Camden NJ 08103 USA
| | - Gregory Kubicek
- Department of Radiation Oncology; MD Anderson Cancer Center at Cooper; Camden NJ 08103 USA
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20
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Adler JR, Schweikard A, Achkire Y, Blanck O, Bodduluri M, Ma L, Zhang H. Treatment Planning for Self-Shielded Radiosurgery. Cureus 2017; 9:e1663. [PMID: 29152420 PMCID: PMC5677342 DOI: 10.7759/cureus.1663] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A five degree of freedom, robotic, radiosurgical system dedicated to the brain is currently under development. In the proposed design, the machine is entirely self-shielded. The main advantage of a self-shielded system is the simplification of the system's installation, which can reduce the cost of radiosurgery. In this way, more patients can benefit from this minimally invasive and highly effective type of procedure. For technical reasons, space inside the shielded region is limited, which leads to constraints on the design. Here, two axes of rotation move a 3-megavolt linear accelerator around the patient’s head at a source axis distance of 400 millimeters (mm), while the integrated patient table is characterized by two additional rotational, and one translational, degrees of freedom. Eight cone collimators of different diameters are available. The system can change the collimator automatically during treatment, using a collimator wheel. Since the linear accelerator can only move with two rotational axes, it is not possible to reposition the beam translationally (as it is in six degrees of freedom robotic radiosurgery). To achieve translational repositioning, it is necessary to move the patient couch. Thus, translational repositioning must be kept to a minimum during treatment. Our goal in this contribution is a preliminary investigation of dose distributions attainable with this type of design. Thus, we do not intend to design and evaluate the treatment planning system itself, but rather to establish that appropriate dose distributions can be achieved with this design under realistic clinical circumstances. Our simulation suggests that dose gradients and conformity for complex target shapes, corresponding to state-of-the-art systems, can be achieved with this construction, although a detailed evaluation of the system itself would be needed in the future.
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Affiliation(s)
- John R Adler
- Department of Neurosurgery, Stanford University School of Medicine
| | - Achim Schweikard
- Institute for Robotics and Cognitive Systems, University of Luebeck, Institute for Robotics and Cognitive Systems, University of Lubeck
| | | | - Oliver Blanck
- Department for Radiation Oncology, University Medical Center Schleswig-Holstein, Campus Kiel, Germany
| | | | - Lijun Ma
- Department of Radiation Oncology, University of California, San Francisco
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21
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Hellerbach A, Luyken K, Hoevels M, Gierich A, Rueß D, Baus WW, Kocher M, Ruge MI, Treuer H. Radiotoxicity in robotic radiosurgery: proposing a new quality index for optimizing the treatment planning of brain metastases. Radiat Oncol 2017; 12:136. [PMID: 28818094 PMCID: PMC5561581 DOI: 10.1186/s13014-017-0867-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Accepted: 08/09/2017] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND As irradiated brain volume at 12 Gy (V12) is a predictor for radionecrosis, the purpose of the study was to develop a model for Cyberknife (CK) plans that is able to predict the lowest achievable V12 at a given tumor size and prescription dose (PD), and to suggest a new quality index regarding V12 for optimizing the treatment planning of brain metastases. METHOD In our model V12 was approximated as a spherical shell around the tumor volume. The radial distance between tumor surface and the 12 Gy isodose line was calculated using an approximation of the mean dose gradient in that area. Assuming a radially symmetrical irradiation from the upper half space, the dose distribution is given by the superposition of single fields. The dose profiles of a single field were derived by the measured off-center ratios (OCR) of the CK system. Using the calculated gradients of the sum dose profiles, minimal-V12 was estimated for different tumor sizes. The model calculation was tested using a phantom dataset and retrospectively applied on clinical cases. RESULTS Our model allows the prediction of a best-case scenario for V12 at a given tumor size and PD which was confirmed by the results of the isocentric phantom plans. The results of the non-isocentric phantom plans showed that an optimization of coverage caused an increase in V12. This was in accordance with the results of the retrospective analysis. V12 s of the clinical cases were on average twice that of the predicted model calculation. A good agreement was achieved for plans with an optimal conformity index (nCI). Re-planning of cases with high V12 showed that lower values could be reached by selecting smaller collimators and by allowing a larger number of total MU and more MU per beam. CONCLUSIONS V12 is a main parameter for assessing plan quality in terms of radiotoxicity. The index f12 defined as the ratio of V12 from the actual plan with the evaluated V12 from our model describes the conformity of an optimally possible V12 and thus can be used as a new quality index for optimizing treatment plans.
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Affiliation(s)
- Alexandra Hellerbach
- Department of Stereotaxy and Functional Neurosurgery, University Hospital Cologne, Cologne, Germany
| | - Klaus Luyken
- Department of Stereotaxy and Functional Neurosurgery, University Hospital Cologne, Cologne, Germany
| | - Mauritius Hoevels
- Department of Stereotaxy and Functional Neurosurgery, University Hospital Cologne, Cologne, Germany
| | - Andreas Gierich
- Department of Stereotaxy and Functional Neurosurgery, University Hospital Cologne, Cologne, Germany
| | - Daniel Rueß
- Department of Stereotaxy and Functional Neurosurgery, University Hospital Cologne, Cologne, Germany
| | - Wolfgang W. Baus
- Department of Radiotherapy, University Hospital Cologne, Cologne, Germany
| | - Martin Kocher
- Department of Radiotherapy, University Hospital Cologne, Cologne, Germany
| | - Maximilian I. Ruge
- Department of Stereotaxy and Functional Neurosurgery, University Hospital Cologne, Cologne, Germany
| | - Harald Treuer
- Department of Stereotaxy and Functional Neurosurgery, University Hospital Cologne, Cologne, Germany
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22
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Kurosu K, Sumida I, Shiomi H, Mizuno H, Yamaguchi H, Okubo H, Tamari K, Seo Y, Suzuki O, Ota S, Inoue S, Ogawa K. A robust measurement point for dose verification in delivery quality assurance for a robotic radiosurgery system. JOURNAL OF RADIATION RESEARCH 2017; 58:378-385. [PMID: 27811201 PMCID: PMC5440860 DOI: 10.1093/jrr/rrw103] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 09/28/2016] [Indexed: 05/17/2023]
Abstract
In this CyberKnife® dose verification study, we investigated the effectiveness of the novel potential error (PE) concept when applied to the determination of a robust measurement point for targeting errors. PE was calculated by dividing the differences between the maximum increases and decreases in dose distributions by the original distribution after obtaining the former by shifting the source-to-axis and off-axis distances of each beam by ±1.0 mm. Thus, PE values and measurement point dose heterogeneity were analyzed in 48 patients who underwent CyberKnife radiotherapy. Sixteen patients who received isocentric dose delivery were set as the control group, whereas 32 who received non-isocentric dose delivery were divided into two groups of smaller PE (SPE) and larger PE (LPE) by using their median PE value. The mean dose differences (± standard deviations) were 1.0 ± 0.9%, 0.5 ± 1.4% and 4.1 ± 2.8% in the control, SPE and LPE groups, respectively. We observed significant correlations of the dose difference with the PE value (r = 0.582, P < 0.001) and dose heterogeneity (r = 0.471, P < 0.001). We concluded that when determining a robust measurement point for CyberKnife point dose verification, PE evaluation was more effective than the conventional dose heterogeneity-based method that introduced optimal measurement point dose heterogeneity of <10% across the detector.
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Affiliation(s)
- Keita Kurosu
- Department of Radiation Oncology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
- Department of Radiology, Osaka University Hospital, 2-15 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Iori Sumida
- Department of Radiation Oncology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
- Corresponding author. Department of Radiation Oncology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan. Tel: +81-6-6879-3482; Fax: +81-6-6879-3489;
| | - Hiroya Shiomi
- Department of Radiation Oncology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Hirokazu Mizuno
- Department of Radiation Oncology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Hiroko Yamaguchi
- Department of Radiation Oncology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Hirofumi Okubo
- Department of Radiation Oncology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Keisuke Tamari
- Department of Radiation Oncology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Yuji Seo
- Department of Radiation Oncology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Osamu Suzuki
- Department of Radiation Oncology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Seiichi Ota
- Department of Radiology, Osaka University Hospital, 2-15 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Shinichi Inoue
- Department of Radiology, Osaka University Hospital, 2-15 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Kazuhiko Ogawa
- Department of Radiation Oncology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
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23
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Wang S, Wang A, Lin J, Xie Y, Wu L, Huang H, Bian J, Yang X, Wan X, Zhao H, Huang J. Brain metastases from hepatocellular carcinoma: recent advances and future avenues. Oncotarget 2017; 8:25814-25829. [PMID: 28445959 PMCID: PMC5421971 DOI: 10.18632/oncotarget.15730] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 02/07/2017] [Indexed: 12/25/2022] Open
Abstract
The incidence of brain metastases from hepatocellular carcinoma (BMHCC) is becoming more frequent than that of the past as a result of prolonged survival of patients with HCC. Compared with brain metastases from other types of cancer, BMHCC tends to exhibit a high incidence of intracerebral hemorrhage (ICH) and poor liver function. Unfortunately, the prognosis is extremely poor for patients with BMHCC owing to the limited treatment selection. Currently, optimal treatment requires multidisciplinary approaches including surgery, whole-brain radiation therapy and stereotactic radiosurgery. Besides these traditional approaches, novel treatments such as target therapy and immunotherapy provide an opportunity to improve the survival of these patients. This review provides an overview of the incidence, characteristics, prognosis, and current and potential future management strategies for BMHCC.
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Affiliation(s)
- Shanshan Wang
- Department of Liver Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Anqiang Wang
- Department of Liver Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Jianzhen Lin
- Department of Liver Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Yuan Xie
- Department of Liver Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Liangcai Wu
- Department of Liver Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Hanchun Huang
- Department of Liver Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Jin Bian
- Department of Liver Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Xiaobo Yang
- Department of Liver Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Xueshuai Wan
- Department of Liver Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Haitao Zhao
- Department of Liver Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
- Center of Translational Medicine, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Jiefu Huang
- Department of Liver Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
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Zhuang H, Zheng Y, Wang J, Chang JY, Wang X, Yuan Z, Wang P. Analysis of risk and predictors of brain radiation necrosis after radiosurgery. Oncotarget 2016; 7:7773-9. [PMID: 26675376 PMCID: PMC4884953 DOI: 10.18632/oncotarget.6532] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 11/25/2015] [Indexed: 11/25/2022] Open
Abstract
In this study, we examined the factors contributing to brain radiation necrosis and its predictors of patients treated with Cyberknife radiosurgery. A total of 94 patients with primary or metastatic brain tumours having been treated with Cyberknife radiotherapy from Sep. 2006 to Oct. 2011 were collected and retrospectively analyzed. Skull based tracking was used to deliver radiation to 104 target sites. and the prescribed radiation doses ranged from 1200 to 4500 cGy in 1 to 8 fractions with a 60% to 87% isodose line. Radiation necrosis was confirmed by imaging or pathological examination. Associations between cerebral radiation necrosis and factors including diabetes, cardio-cerebrovascular disease, target volume, isodose line, prescribed dosage, number of fractions, combination with whole brain radiation and biologically equivalent dose (BED) were determined by logistic regression. ROC curves were created to measure the predictive accuracy of influence factors and identify the threshold for brain radiation necrosis. Our results showed that radiation necrosis occurred in 12 targets (11.54%). Brain radiation necrosis was associated by BED, combination with whole brain radiotherapy, and fractions (areas under the ROC curves = 0.892±0.0335, 0.650±0.0717, and 0.712±0.0637 respectively). Among these factors, only BED had the capability to predict brain radiation necrosis, and the threshold dose was 7410 cGy. In conclusion, BED is the most effective predictor of brain radiation necrosis, with a dose of 7410 cGy being identified as the threshold.
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Affiliation(s)
- Hongqing Zhuang
- Department of Radiotherapy, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Tianjin Key Laboratory of Cancer Prevention and Therapy and Tianjin Lung Cancer Center, Tianjin, China
| | - Yi Zheng
- Daqing Oilfield General Hospital, Heilongjiang, China
| | - Junjie Wang
- Department of Radiotherapy, Peking University 3rd Hospital, Beijing, China
| | - Joe Y Chang
- Department of Radiation Oncology, Division of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Xiaoguang Wang
- Department of Radiotherapy, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Tianjin Key Laboratory of Cancer Prevention and Therapy and Tianjin Lung Cancer Center, Tianjin, China
| | - Zhiyong Yuan
- Department of Radiotherapy, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Tianjin Key Laboratory of Cancer Prevention and Therapy and Tianjin Lung Cancer Center, Tianjin, China
| | - Ping Wang
- Department of Radiotherapy, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Tianjin Key Laboratory of Cancer Prevention and Therapy and Tianjin Lung Cancer Center, Tianjin, China
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Keeling V, Algan O, Ahmad S, Hossain S. Dosimetric comparison of intracranial metastasis treatment using two radiosurgery systems: TrueBeam STx with VMAT and Gamma Knife Model 4C. JOURNAL OF RADIOSURGERY AND SBRT 2016; 4:235-243. [PMID: 29296448 PMCID: PMC5658806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Accepted: 08/08/2016] [Indexed: 06/07/2023]
Abstract
We compared treatment plan quality based on target coverage and normal brain tissue sparing for two intracranial stereotactic radiosurgery systems: TrueBeam STx using VMAT and Gamma Knife (GK). Ten patients with 24 tumors (seven with 1-2 and three with 4-6 ranging from 0.1 to 20.2 cc), previously treated with GK Model 4C (prescription doses ranging from 14-23 Gy), were re-planned for VMAT using Eclipse treatment planning system. Various photon beam energies and MLC leaf widths with and without jaw tracking were studied to achieve optimal plans. Plan qualities were assessed by target coverages using Paddick Conformity Index (PCI), normal-brain-tissue integral dose (Gy-cc) and sparing. In all cases critical structure dose criteria were met. The average PCI was 0.76±0.21 for VMAT and 0.46±0.20 for GK plans (p≤0.001), respectively. On average 81% reduction of 12 Gy normal-brain-tissue volumes was achieved by VMAT. The average integral dose ratio of GK to VMAT plans was 1.50±0.61 (p=0.006). VMAT was capable of producing higher quality treatment plans in terms of target coverage and normal brain tissue sparing than GK while using optimal beam geometries and optimization techniques.
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Affiliation(s)
- Vance Keeling
- Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73013, USA
| | - Ozer Algan
- Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73013, USA
| | - Salahuddin Ahmad
- Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73013, USA
| | - Sabbir Hossain
- Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73013, USA
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Shiraishi S, Tan J, Olsen LA, Moore KL. Knowledge-based prediction of plan quality metrics in intracranial stereotactic radiosurgery. Med Phys 2015; 42:908. [PMID: 25652503 DOI: 10.1118/1.4906183] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
PURPOSE The objective of this work was to develop a comprehensive knowledge-based methodology for predicting achievable dose-volume histograms (DVHs) and highly precise DVH-based quality metrics (QMs) in stereotactic radiosurgery/radiotherapy (SRS/SRT) plans. Accurate QM estimation can identify suboptimal treatment plans and provide target optimization objectives to standardize and improve treatment planning. METHODS Correlating observed dose as it relates to the geometric relationship of organs-at-risk (OARs) to planning target volumes (PTVs) yields mathematical models to predict achievable DVHs. In SRS, DVH-based QMs such as brain V10Gy (volume receiving 10 Gy or more), gradient measure (GM), and conformity index (CI) are used to evaluate plan quality. This study encompasses 223 linear accelerator-based SRS/SRT treatment plans (SRS plans) using volumetric-modulated arc therapy (VMAT), representing 95% of the institution's VMAT radiosurgery load from the past four and a half years. Unfiltered models that use all available plans for the model training were built for each category with a stratification scheme based on target and OAR characteristics determined emergently through initial modeling process. Model predictive accuracy is measured by the mean and standard deviation of the difference between clinical and predicted QMs, δQM = QMclin - QMpred, and a coefficient of determination, R(2). For categories with a large number of plans, refined models are constructed by automatic elimination of suspected suboptimal plans from the training set. Using the refined model as a presumed achievable standard, potentially suboptimal plans are identified. Predictions of QM improvement are validated via standardized replanning of 20 suspected suboptimal plans based on dosimetric predictions. The significance of the QM improvement is evaluated using the Wilcoxon signed rank test. RESULTS The most accurate predictions are obtained when plans are stratified based on proximity to OARs and their PTV volume sizes. Volumes are categorized into small (VPTV < 2 cm(3)), medium (2 cm(3) < VPTV < 25 cm(3)), and large (25 cm(3) < VPTV). The unfiltered models demonstrate the ability to predict GMs to ∼1 mm and fractional brain V10Gy to ∼25% for plans with large VPTV and critical OAR involvements. Increased accuracy and precision of QM predictions are obtained when high quality plans are selected for the model training. For the small and medium VPTV plans without critical OAR involvement, predictive ability was evaluated using the refined model. For training plans, the model predicted GM to an accuracy of 0.2 ± 0.3 mm and fractional brain V10Gy to 0.04 ± 0.12, suggesting highly accurate predictive ability. For excluded plans, the average δGM was 1.1 mm and fractional brain V10Gy was 0.20. These δQM are significantly greater than those of the model training plans (p < 0.001). For CI, predictions are close to clinical values and no significant difference was observed between the training and excluded plans (p = 0.19). Twenty outliers with δGM > 1.35 mm were identified as potentially suboptimal, and replanning these cases using predicted target objectives demonstrates significant improvements on QMs: on average, 1.1 mm reduction in GM (p < 0.001) and 23% reduction in brain V10Gy (p < 0.001). After replanning, the difference of δGM distribution between the 20 replans and the refined model training plans was marginal. CONCLUSIONS The results demonstrate the ability to predict SRS QMs precisely and to identify suboptimal plans. Furthermore, the knowledge-based DVH predictions were directly used as target optimization objectives and allowed a standardized planning process that bettered the clinically approved plans. Full clinical application of this methodology can improve consistency of SRS plan quality in a wide range of PTV volume and proximity to OARs and facilitate automated treatment planning for this critical treatment site.
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Affiliation(s)
- Satomi Shiraishi
- Department of Radiation Medicine and Applied Sciences, University of California, San Diego, La Jolla, California 92093
| | - Jun Tan
- Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, Texas 75490
| | - Lindsey A Olsen
- Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Kevin L Moore
- Department of Radiation Medicine and Applied Sciences, University of California, San Diego, La Jolla, California 92093
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Lee SW, Jang S, Pyakuryal AP, Chang K, Sio TT. The impact of CyberKnife's prescription isodose percentage on intracranial target planning. J Appl Clin Med Phys 2014; 15:5081. [PMID: 25207584 PMCID: PMC5711081 DOI: 10.1120/jacmp.v15i5.5081] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Accepted: 05/15/2014] [Indexed: 11/23/2022] Open
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