1
|
Plaza D, Sroka Ł, Orzechowska K, Ślosarek K. Comparison of the dose distribution of the VMAT radiotherapy technique depending on the beam used: FFF-X10MV and FFF-X15MV. Rep Pract Oncol Radiother 2023; 28:654-660. [PMID: 38179296 PMCID: PMC10764046 DOI: 10.5603/rpor.97508] [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: 03/27/2023] [Accepted: 09/18/2023] [Indexed: 01/06/2024] Open
Abstract
Background The aim of the study was to answer the question of whether flattening filter (FF) and flattening filter-free (FFF) beams can be used alternately in the volumetric modulated arc therapy (VMAT) treatment technique, regardless of the size of the irradiated volume [small (S) or large (L) planning target volume (PTV)]. Materials and methods Two groups of patients were examined: a group with a S-PTV-laryngeal cancer and a group with a L-PTV - gynecological volume. For each patient, two treatment plans were made for beams (energies): FFF-X10MV and FF-X15MV. Then, a statistical analysis, nonparametric test, and independent groups were performed, comparing the beams' impact on the analyzed treatment plans. Results In the case of laryngeal irradiation (S-PTV), there are no statistically significant differences between the energy used and the assessed parameters of the plan. In the case of gynecological volume (L-PTV), only statistically significant differences were noted for the number of monitor units depending on the energy used. For a large irradiated volume (gynecological case), the use of FFF beams increases the number of monitor units by 39,4% in relation to the FF beam. Conclusions In the case of gynecological neoplasms, statistically significant differences were found in the number of monitor units. Therefore, in the case of irradiation of L-PTV, it is recommended that flattening-filtering beams are used due to the smaller number of monitors. In the case of S-PTV, no statistically significant differences were found between the types of beams used (FF or FFF) and the treatment plan parameters analyzed in the study.
Collapse
Affiliation(s)
- Dominika Plaza
- Radiotherapy Planning Department, Maria Skłodowska-Curie National Research Institute of Oncology, Gliwice Branch, Poland
| | - Łukasz Sroka
- Radiotherapy Planning Department, Maria Skłodowska-Curie National Research Institute of Oncology, Gliwice Branch, Poland
| | - Klaudia Orzechowska
- Radiotherapy Planning Department, Maria Skłodowska-Curie National Research Institute of Oncology, Gliwice Branch, Poland
| | - Krzysztof Ślosarek
- Radiotherapy Planning Department, Maria Skłodowska-Curie National Research Institute of Oncology, Gliwice Branch, Poland
| |
Collapse
|
2
|
Ogino I, Seto H, Shigenaga D, Hata M. Dose to contralateral breast from whole breast irradiation by automated tangential IMRT planning: comparison of flattening-filter and flattening-filter-free modes. Rep Pract Oncol Radiother 2022; 27:113-120. [PMID: 35402036 PMCID: PMC8989456 DOI: 10.5603/rpor.a2022.0006] [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: 09/23/2021] [Accepted: 11/20/2021] [Indexed: 11/25/2022] Open
Abstract
Background The most common secondary cancer is contralateral breast (CLB) cancer after whole breast irradiation (WBI). The aim of this study was to quantify the reduction of CLB dose in tangential intensity modulated radiotherapy (t-IMRT) for WBI using flattening-filter-free (FFF) beams. Materials and methods We generated automated planning of 20 young breast cancer patients with limited user interaction. Dose-volume histograms of the planning target volume (PTV), ipsilateral lung, heart, and CLB were calculated. The dose of PTV, the most medial CLB point, and the CLB point below the nipple was measured using an ionization chamber inserted in a slab phantom. We compared the two t-IMRT plans generated by FFF beams and flattening-filter (FF) beams. Results All plans were clinically acceptable. There was no difference in the conformal index, the homogeneity for FFF was significantly worse. For the ipsilateral lung, the maximum dose (Dmax) was significantly higher; however, V20 showed a tendency to be lower in the FFF plan. No differences were found in the Dmax and V30 to the heart of the left breast cancer. FF planning showed significantly lower Dmax and mean dose to the CLB. In contrast to the calculation results, the measured dose of the most medial CLB point and the CLB point below the nipple were significantly lower in FFF mode than in FF mode, with mean reductions of 21.1% and 20%, respectively. Conclusions T-IMRT planning using FFF reduced the measured out-of-field dose of the most medial CLB point and the CLB point below the nipple.
Collapse
Affiliation(s)
- Ichiro Ogino
- Department of Radiation Oncology, Yokohama City University Medical Center, Yokohama, Japan
| | - Hidetaka Seto
- Department of Radiation Oncology, Yokohama City University Medical Center, Yokohama, Japan.,Department of Radiation Oncology, Ishikawa Prefectural Central Hospital, Ishikawa, Japan
| | - Daisuke Shigenaga
- Department of Radiation Oncology, Yokohama City University Medical Center, Yokohama, Japan
| | - Masaharu Hata
- Division of Radiation Oncology, Department of Oncology, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| |
Collapse
|
3
|
Bi S, Zhu R, Dai Z. Dosimetric and radiobiological comparison of simultaneous integrated boost radiotherapy for early stage right side breast cancer between three techniques: IMRT, hybrid IMRT and hybrid VMAT. Radiat Oncol 2022; 17:60. [PMID: 35346264 PMCID: PMC8962055 DOI: 10.1186/s13014-022-02009-2] [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: 06/27/2021] [Accepted: 02/13/2022] [Indexed: 11/25/2022] Open
Abstract
Purpose This study aimed at evaluating the clinical impact of full intensity-modulated radiotherapy (IMRT), hybrid IMRT (H-IMRT) and hybrid volumetric-modulated arc therapy (H-VMAT) for early-stage breast cancer with simultaneous integrated boost (SIB), in terms of plan quality and second cancer risk (SCR). Methods Three different plans were designed in full IMRT, hybrid IMRT, and hybrid VMAT for each of twenty patients with early-stage breast cancer. Target quality, organs at risk (OARs) sparing, and SCR were compared among the three plans for each case. Results In compared with H-IMRT, IMRT plans showed deterioration in terms of D2% of SIB, V10 of ipsilateral lung, and excess absolute risk (EAR) to contralateral lung (C-Lung) and esophagus. D2% and the homogeneity index (HI) of SIB, V5 of ipsilateral lung (I-Lung), the Dmean of the esophagus, the EAR to C-Lung and the esophagus with hybrid VMAT dramatically increased by 0.63%, 10%, 17.99%, 149.27%, 230.41%, and 135.29%, respectively (p = 0.024; 0.025; 0.046; 0.011; 0.000; 0.014). Dmean of the heart, the EAR to contralateral breast (C-Breast) and C-Lung by full IMRT was significantly decreased in comparison to the H-VMAT (4.67%, p = 0.033, 26.76%, p = 0.018; 48.05%, p = 0.036). Conclusion The results confirmed that H-IMRT could achieve better target quality and OARs sparing than IMRT and H-VMAT for SIB radiotherapy of early-stage right breast cancer. H-IMRT was the best treatment option, while H-VMAT performed the worst among the three plans in terms of SCR to peripheral OARs.
Collapse
Affiliation(s)
- Suyan Bi
- National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital & Shenzhen Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Shenzhen, 518116, China
| | - Rui Zhu
- Department of Oncology, Yunyang County People's Hospital, Chongqing, 404500, China
| | - Zhitao Dai
- National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital & Shenzhen Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Shenzhen, 518116, China.
| |
Collapse
|
4
|
Synchronous bilateral breast carcinoma irradiation: A comparative investigation between flattened and unflattened beams. Appl Radiat Isot 2022; 181:110079. [DOI: 10.1016/j.apradiso.2021.110079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 12/18/2021] [Accepted: 12/21/2021] [Indexed: 12/24/2022]
|
5
|
Effects of flattening filter (FF) and flattening filter-free (FFF) beams on small-field and large-field dose distribution using the VMAT treatment plan. POLISH JOURNAL OF MEDICAL PHYSICS AND ENGINEERING 2021. [DOI: 10.2478/pjmpe-2021-0016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Abstract
Introduction: The aim of the study was to evaluate the influence of flattening filter (FF) and flattening filter-free (FFF) beams on small-field and large-field dose distribution using the VMAT treatment plan.
Material and methods: Dose distribution calculations were performed for the VMAT technique in two locations: the larynx (small irradiation field; average 30.1 cm2) and gynecology (large irradiation field; average 173.1 cm2) using X-6MV flattening filter (FF) and flattening filter-free (FFF) beams. The following values were compared: the number of monitor units, minimum doses, average doses in PTV and maximum average doses in OaR (spinal cord – in larynx radiotherapy, bladder and rectum - in gynecological radiotherapy) and RPI (Radiation Planning Index) coefficient.
Results and Discussion: The performed statistical tests indicate that there is a significant difference (p <0.05) between the number of monitor units in the irradiation of large (gynecological) fields between the FF and FFF beams. The dose distributions show no statistically significant differences between the flattening filter and flattening-free filter beams (regardless of the field size).
Conclusions: Due to the smaller number of monitor units, it is recommended to use flattening filter beams (FF) for large-field radiotherapy.
Collapse
|
6
|
Treutwein M, Loeschel R, Hipp M, Koelbl O, Dobler B. Secondary malignancy risk for patients with localized prostate cancer after intensity-modulated radiotherapy with and without flattening filter. J Appl Clin Med Phys 2020; 21:197-205. [PMID: 33147377 PMCID: PMC7769399 DOI: 10.1002/acm2.13088] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 09/16/2020] [Accepted: 07/24/2020] [Indexed: 12/20/2022] Open
Abstract
Men treated for localized prostate cancer by radiotherapy have often a remaining life span of 10 yr or more. Therefore, the risk for secondary malignancies should be taken into account. Plans for ten patients were evaluated which had been performed on an Oncentra® treatment planning system for a treatment with an Elekta Synergy™ linac with Agility™ head. The investigated techniques involved IMRT and VMTA with and without flattening filter. Different dose response models were applied for secondary carcinoma and sarcoma risk in the treated region and also in the periphery. As organs at risk we regarded for carcinoma risk urinary bladder, rectum, colon, esophagus, thyroid, and for sarcoma risk bone and soft tissue. The excess absolute risk (EAR) was found very similar in the treated region for both techniques (IMRT and VMAT) and also for both with and without flattening filter. The secondary sarcoma risk resulted about one magnitude smaller than the secondary carcinoma risk. The EAR to the peripheral organs was statistically significant reduced by application of the flattening filter free mode concerning the flattening filter as main source of scattered dose. Application of flattening filter free mode can thus support to reduce second malignancy risk for patients with localized prostate cancer.
Collapse
Affiliation(s)
- Marius Treutwein
- Department for radiotherapy, Regensburg University Medical Center, Regensburg, Germany
| | - Rainer Loeschel
- Faculty of computer science and mathematics, Ostbayerische Technische Hochschule, Regensburg, Germany
| | - Matthias Hipp
- Department for radiotherapy, Regensburg University Medical Center, Regensburg, Germany.,Strahlentherapie, Klinikum St. Marien, Amberg, Germany
| | - Oliver Koelbl
- Department for radiotherapy, Regensburg University Medical Center, Regensburg, Germany
| | - Barbara Dobler
- Department for radiotherapy, Regensburg University Medical Center, Regensburg, Germany
| |
Collapse
|
7
|
Treutwein M, Steger F, Loeschel R, Koelbl O, Dobler B. The influence of radiotherapy techniques on the plan quality and on the risk of secondary tumors in patients with pituitary adenoma. BMC Cancer 2020; 20:88. [PMID: 32013920 PMCID: PMC6998093 DOI: 10.1186/s12885-020-6535-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Accepted: 01/13/2020] [Indexed: 12/20/2022] Open
Abstract
Background This planning study compares different radiotherapy techniques for patients with pituitary adenoma, including flatness filter free mode (FFF), concerning plan quality and secondary malignancies for potentially young patients. The flatness filter has been described as main source of photon scatter. Material and methods Eleven patients with pituitary adenoma were included. An Elekta Synergy™ linac was used in the treatment planning system Oncentra® and for the measurements. 3D plans, IMRT, and VMAT plans and non-coplanar varieties were considered. The plan quality was evaluated regarding homogeneity, conformity, delivery time and dose to the organs at risk. The secondary malignancy risk was calculated from dose volume data and from measured dose to the periphery using different models for carcinoma and sarcoma risk. Results The homogeneity and conformity were nearly unchanged with and without flattening filter, neither was the delivery time found substantively different. VMAT plans were more homogenous, conformal and faster in delivery than IMRT plans. The secondary cancer risk was reduced with FFF both in the treated region and in the periphery. VMAT plans resulted in a higher secondary brain cancer risk than IMRT plans, but the risk for secondary peripheral cancer was reduced. Secondary sarcoma risk plays a minor role. No advantage was found for non-coplanar techniques. The FFF delivery times were not shortened due to additional monitor units needed and technical limitations. The risk for secondary brain cancer seems to depend on the irradiated volume. Secondary sarcoma risk is much smaller than carcinoma risk in accordance to the results of the atomic bomb survivors. The reduction of the peripheral dose and resulting secondary malignancy risk for FFF is statistically significant. However, it is negligible in comparison to the risk in the treated region. Conclusion Treatments with FFF can reduce secondary malignancy risk while retaining similar quality as with flattening filter and should be preferred. VMAT plans show the best plan quality combined with lowest peripheral secondary malignancy risk, but highest level of second brain cancer risk. Taking this into account VMAT FFF seems the most advantageous technique for the treatment of pituitary adenomas with the given equipment.
Collapse
Affiliation(s)
- Marius Treutwein
- Department for radiotherapy, Regensburg University Medical Center, Regensburg, Germany.
| | - Felix Steger
- Department for radiotherapy, Regensburg University Medical Center, Regensburg, Germany
| | - Rainer Loeschel
- Faculty of computer science and mathematics, Ostbayerische Technische Hochschule, Regensburg, Germany
| | - Oliver Koelbl
- Department for radiotherapy, Regensburg University Medical Center, Regensburg, Germany
| | - Barbara Dobler
- Department for radiotherapy, Regensburg University Medical Center, Regensburg, Germany
| |
Collapse
|
8
|
Hybrid planning techniques for hypofractionated whole-breast irradiation using flattening filter-free beams. Strahlenther Onkol 2019; 196:376-385. [PMID: 31863154 DOI: 10.1007/s00066-019-01555-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 11/21/2019] [Indexed: 12/25/2022]
Abstract
OBJECTIVE The aim of this study was to assess the feasibility of flattening filter-free (FFF) photon beams in hybrid intensity-modulated radiation therapy (H-IMRT) and hybrid volumetric modulated arc therapy (H-VMAT) for left-sided whole-breast radiation therapy with a boost volume (RT) using a hypofractionated dose regimen. PATIENTS AND METHODS RT plans of 25 patients with left-sided early-stage breast cancer were created with H‑IMRT and H‑VMAT techniques under breath-hold conditions using 6‑MV FFF beams. In hybrid techniques, three-dimensional conformal radiotherapy (3DCRT) plans were kept as base-dose plans for the VMAT and IMRT plans. In addition, H‑IMRT in step-and-shoot mode was also calculated to assess its achievability with FFF beams. RESULTS All hybrid plans achieved the expected target coverage. H‑VMAT showed better coverage and homogeneity index results for the boost target (p < 0.002), while H‑IMRT presented better results for the whole-breast target (p < 0.001). Mean doses to normal tissues were comparable between both plans, while H‑IMRT reduced the low-dose levels to heart and ipsilateral lung (p < 0.05). H‑VMAT revealed significantly better results with regard to monitor units (MU) and treatment time (p < 0.001). CONCLUSION The 6‑MV FFF beam technique is feasible for large-field 3DCRT-based hybrid planning in whole-breast and boost planning target volume irradiation. For breath-hold patients, the H‑VMAT plan is superior to H‑IMRT for hypofractionated dose regimens, with reduced MU and treatment delivery time.
Collapse
|
9
|
Takahashi W, Nawa K, Haga A, Yamashita H, Imae T, Ogita M, Okuma K, Abe O, Nakagawa K. Acceptable fetal dose using flattening filter-free volumetric arc therapy (FFF VMAT) in postoperative chemoradiotherapy of tongue cancer during pregnancy. Clin Transl Radiat Oncol 2019; 20:9-12. [PMID: 31709307 PMCID: PMC6833340 DOI: 10.1016/j.ctro.2019.10.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Accepted: 10/10/2019] [Indexed: 11/18/2022] Open
Abstract
Optimizing irradiation protocols for pregnant women is challenging, because there are few cases and a dearth of fetal dosimetry data. We cared for a 36-year-old pregnant woman with tongue cancer. Prior to treatment, we compared three intensity-modulated radiation therapy (IMRT) techniques, including helical tomotherapy, volumetric arc therapy (VMAT), and flattening-filter free VMAT (FFF-VMAT) using treatment planning software. FFF-VMAT achieved the minimum fetal exposure and was selected as the optimal modality. We prescribed 66 Gy to the involved nodes, 60 Gy to the tumor bed and ipsilateral neck, and 54 Gy to the contralateral neck over 33 fractions. To confirm the out-of-field exposure per fraction, surface doses and the rectal dose were measured during FFF-VMAT delivery. Postoperative chemoradiotherapy was delivered using IMRT and a cisplatin regimen. Without any shielding, the total fetal dose was 0.03 Gy, within the limits established by the ICRP. A healthy girl was born vaginally at 37 weeks' gestation.
Collapse
Affiliation(s)
- Wataru Takahashi
- Department of Radiology, The University of Tokyo Hospital, Tokyo, Japan
- Corresponding author at: Department of Radiology, The University of Tokyo Hospital, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan.
| | - Kanabu Nawa
- Department of Radiology, The University of Tokyo Hospital, Tokyo, Japan
| | - Akihiro Haga
- Department of Medical Image Informatics, Tokushima University, Tokushima, Japan
| | - Hideomi Yamashita
- Department of Radiology, The University of Tokyo Hospital, Tokyo, Japan
| | - Toshikazu Imae
- Department of Radiology, The University of Tokyo Hospital, Tokyo, Japan
| | - Mami Ogita
- Department of Radiology, The University of Tokyo Hospital, Tokyo, Japan
| | - Kae Okuma
- Department of Radiology, The University of Tokyo Hospital, Tokyo, Japan
| | - Osamu Abe
- Department of Radiology, The University of Tokyo Hospital, Tokyo, Japan
| | - Keiichi Nakagawa
- Department of Radiology, The University of Tokyo Hospital, Tokyo, Japan
| |
Collapse
|
10
|
Schreuder K, Maduro J, Spronk P, Bijker N, Poortmans P, van Dalen T, Struikmans H, Siesling S. Variation in the Use of Boost Irradiation in Breast-Conserving Therapy in the Netherlands: The Effect of a National Guideline and Cofounding Factors. Clin Oncol (R Coll Radiol) 2019; 31:250-259. [DOI: 10.1016/j.clon.2018.11.033] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 11/05/2018] [Accepted: 11/07/2018] [Indexed: 12/25/2022]
|
11
|
Ben Bouchta Y, Goddard K, Petric MP, Bergman AM. Effects of 10 MV and Flattening-Filter-Free Beams on Peripheral Dose in a Cohort of Pediatric Patients. Int J Radiat Oncol Biol Phys 2018; 102:1560-1568. [DOI: 10.1016/j.ijrobp.2018.07.2002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Revised: 07/18/2018] [Accepted: 07/23/2018] [Indexed: 12/25/2022]
|
12
|
Ghaznavi H. Comment on Long-term risks of secondary cancer for various whole and partial breast irradiation techniques. Radiother Oncol 2018; 141:331. [PMID: 30446317 DOI: 10.1016/j.radonc.2018.10.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 10/22/2018] [Accepted: 10/24/2018] [Indexed: 11/16/2022]
Affiliation(s)
- Hamid Ghaznavi
- Engineering and Medical Physics Department, Isfahan University of Medical Sciences, Isfahan, Iran
| |
Collapse
|
13
|
Alvarez Moret J, Obermeier T, Pohl F, Loeschel R, Koelbl O, Dobler B. Second cancer risk after radiation therapy of ependymoma using the flattening filter free irradiation mode of a linear accelerator. J Appl Clin Med Phys 2018; 19:632-639. [PMID: 30125453 PMCID: PMC6123158 DOI: 10.1002/acm2.12438] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 06/06/2018] [Accepted: 07/16/2018] [Indexed: 12/05/2022] Open
Abstract
Pediatric patients suffering from ependymoma are usually treated with cranial or craniospinal three‐dimensional (3D) conformal radiotherapy (3DCRT). Intensity‐modulated techniques spare dose to the surrounding tissue, but the risk for second malignancies may be increased due to the increase in low‐dose volume. The aim of this study is to investigate if the flattening filter free (FFF) mode allows reducing the risk for second malignancies compared to the mode with flattening filter (FF) for intensity‐modulated techniques and to 3DCRT. A reduction of the risk would be advantageous for treating pediatric ependymoma. 3DCRT was compared to intensity‐modulated radiation therapy (IMRT) and volumetric‐modulated arc therapy (VMAT) with and without flattening filter. Dose–volume histograms (DVHs) were compared to evaluate the plan quality and used to calculate the excess absolute risk (EAR) to develop second cancer in the brain. Dose verification was performed with a two‐dimensional (2D) ionization chamber array and the out‐of‐field dose was measured with an ionization chamber to determine the EAR in peripheral organs. Delivery times were measured. Both VMAT and IMRT achieved similar plan quality in terms of dose sparing in the OAR and higher PTV coverage as compared to 3DCRT. Peripheral dose in low‐dose region, which is proportional to the EAR in organs located in this region, for example, gonads, bladder, or bowel, could be significantly reduced using FFF. The lowest peripheral EAR and lowest delivery times were hereby achieved with VMATFFF. The EAR calculated based on DVH in the brain could not be reduced using FFF mode. VMATFFF improved the target coverage and homogeneity and kept the dose in the OAR similar compared to 3DCRT. In addition, delivery times were significantly reduced using VMATFFF. Therefore, for radiotherapy of ependymoma patients, VMATFFF may be considered advantageous for the combination of Elekta Synergy linac and Oncentra External Beam planning system used in this study.
Collapse
Affiliation(s)
- Judit Alvarez Moret
- Department of Radiotherapy, Regensburg University Medical Center, Regensburg, Germany
| | - Tina Obermeier
- Department of Radiotherapy, Regensburg University Medical Center, Regensburg, Germany
| | - Fabian Pohl
- Department of Radiotherapy, Regensburg University Medical Center, Regensburg, Germany
| | - Rainer Loeschel
- Department of Computer Science and Mathematics, University of Applied Sciences, OTH Regensburg, Regensburg, Germany
| | - Oliver Koelbl
- Department of Radiotherapy, Regensburg University Medical Center, Regensburg, Germany
| | - Barbara Dobler
- Department of Radiotherapy, Regensburg University Medical Center, Regensburg, Germany
| |
Collapse
|
14
|
Cozzi L, Lohr F, Fogliata A, Franceschini D, De Rose F, Filippi AR, Guidi G, Vanoni V, Scorsetti M. Critical appraisal of the role of volumetric modulated arc therapy in the radiation therapy management of breast cancer. Radiat Oncol 2017; 12:200. [PMID: 29258539 PMCID: PMC5735809 DOI: 10.1186/s13014-017-0935-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 12/05/2017] [Indexed: 02/06/2023] Open
Abstract
Background The aim of this review is the critical appraisal of the current use of volumetric modulated arc therapy for the radiation therapy management of breast cancer. Both clinical and treatment planning studies were investigated. Material and methods A Pubmed/MEDLINE search of the National Library of Medicine was performed to identify VMAT and breast related articles. After a first order rejection of the irrelevant findings, the remaining articles were grouped according to two main categories: clinical vs. planning studies and to some sub-categories (pointing to significant technical features). Main areas of application, dosimetric and clinical findings as well as areas of innovations were defined. Results A total of 131 articles were identified and of these, 67 passed a first order selection. Six studies reported clinical results while 61 treatment dealed with treatment planning investigations. Among the innovation lines, the use of high intensity photon beams (flattening filter free), altered fractionation schemes (simultaneous integrated boost, accelerated partial breast irradiation, single fraction), prone positioning and modification of standard VMAT (use of dynamic trajectories or hybrid VMAT methods) resulted among the main relevant fields of interest. Approximately 10% of the publications reported upon respiratory gating in conjunction with VMAT. Conclusions The role of VMAT in the radiation treatment of breast cancer seems to be consolidated in the in-silico arena while still limited evidence and only one phase II trial appeared in literature from the clinical viewpoint. More clinical reports are needed to fully proove the expected dosimetric benefits demonstrated in the planning investigations.
Collapse
Affiliation(s)
- Luca Cozzi
- Radiotherapy and Radiosurgery Department, Humanitas Research Hospital, Via Manzoni 56, 20089, Rozzano-Milan, Italy. .,Department of Biomedical Sciences, Humanitas University, Rozzano, Italy.
| | - Frank Lohr
- Radiation Oncology Department, Ospedaliero-Universitaria, Modena, Italy
| | - Antonella Fogliata
- Radiotherapy and Radiosurgery Department, Humanitas Research Hospital, Via Manzoni 56, 20089, Rozzano-Milan, Italy
| | - Davide Franceschini
- Radiotherapy and Radiosurgery Department, Humanitas Research Hospital, Via Manzoni 56, 20089, Rozzano-Milan, Italy
| | - Fiorenza De Rose
- Radiotherapy and Radiosurgery Department, Humanitas Research Hospital, Via Manzoni 56, 20089, Rozzano-Milan, Italy
| | - A R Filippi
- Department of Radiation Oncology, Osp. S. Luigi Gonzaga University Hospital, Torino, Italy
| | - Gabriele Guidi
- Medical Physics Department, Az. Ospedaliero-Universitaria, Modena, Italy
| | | | - Marta Scorsetti
- Radiotherapy and Radiosurgery Department, Humanitas Research Hospital, Via Manzoni 56, 20089, Rozzano-Milan, Italy.,Department of Biomedical Sciences, Humanitas University, Rozzano, Italy
| |
Collapse
|
15
|
Corradini S, Ballhausen H, Weingandt H, Freislederer P, Schönecker S, Niyazi M, Simonetto C, Eidemüller M, Ganswindt U, Belka C. Left-sided breast cancer and risks of secondary lung cancer and ischemic heart disease : Effects of modern radiotherapy techniques. Strahlenther Onkol 2017; 194:196-205. [PMID: 28916844 DOI: 10.1007/s00066-017-1213-y] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 08/30/2017] [Indexed: 12/25/2022]
Abstract
PURPOSE Modern breast cancer radiotherapy techniques, such as respiratory-gated radiotherapy in deep-inspiration breath-hold (DIBH) or volumetric-modulated arc radiotherapy (VMAT) have been shown to reduce the high dose exposure of the heart in left-sided breast cancer. The aim of the present study was to comparatively estimate the excess relative and absolute risks of radiation-induced secondary lung cancer and ischemic heart disease for different modern radiotherapy techniques. METHODS Four different treatment plans were generated for ten computed tomography data sets of patients with left-sided breast cancer, using either three-dimensional conformal radiotherapy (3D-CRT) or VMAT, in free-breathing (FB) or DIBH. Dose-volume histograms were used for organ equivalent dose (OED) calculations using linear, linear-exponential, and plateau models for the lung. A linear model was applied to estimate the long-term risk of ischemic heart disease as motivated by epidemiologic data. Excess relative risk (ERR) and 10-year excess absolute risk (EAR) for radiation-induced secondary lung cancer and ischemic heart disease were estimated for different representative baseline risks. RESULTS The DIBH maneuver resulted in a significant reduction of the ERR and estimated 10-year excess absolute risk for major coronary events compared to FB in 3D-CRT plans (p = 0.04). In VMAT plans, the mean predicted risk reduction through DIBH was less pronounced and not statistically significant (p = 0.44). The risk of radiation-induced secondary lung cancer was mainly influenced by the radiotherapy technique, with no beneficial effect through DIBH. VMAT plans correlated with an increase in 10-year EAR for radiation-induced lung cancer as compared to 3D-CRT plans (DIBH p = 0.007; FB p = 0.005, respectively). However, the EARs were affected more strongly by nonradiation-associated risk factors, such as smoking, as compared to the choice of treatment technique. CONCLUSION The results indicate that 3D-CRT plans in DIBH pose the lowest risk for both major coronary events and secondary lung cancer.
Collapse
Affiliation(s)
- Stefanie Corradini
- Department of Radiation Oncology, University Hospital, LMU Munich, Marchioninistraße 15, 81377, Munich, Germany.
| | - Hendrik Ballhausen
- Department of Radiation Oncology, University Hospital, LMU Munich, Marchioninistraße 15, 81377, Munich, Germany
| | - Helmut Weingandt
- Department of Radiation Oncology, University Hospital, LMU Munich, Marchioninistraße 15, 81377, Munich, Germany
| | - Philipp Freislederer
- Department of Radiation Oncology, University Hospital, LMU Munich, Marchioninistraße 15, 81377, Munich, Germany
| | - Stephan Schönecker
- Department of Radiation Oncology, University Hospital, LMU Munich, Marchioninistraße 15, 81377, Munich, Germany
| | - Maximilian Niyazi
- Department of Radiation Oncology, University Hospital, LMU Munich, Marchioninistraße 15, 81377, Munich, Germany
| | - Cristoforo Simonetto
- Institute of Radiation Protection, Helmholtz Zentrum München, Neuherberg, Germany
| | - Markus Eidemüller
- Institute of Radiation Protection, Helmholtz Zentrum München, Neuherberg, Germany
| | - Ute Ganswindt
- Department of Radiation Oncology, University Hospital, LMU Munich, Marchioninistraße 15, 81377, Munich, Germany
- Department of Radiation Oncology, Medical University, Innsbruck, Austria
| | - Claus Belka
- Department of Radiation Oncology, University Hospital, LMU Munich, Marchioninistraße 15, 81377, Munich, Germany
| |
Collapse
|
16
|
Treutwein M, Hipp M, Koelbl O, Dobler B. Volumetric-modulated arc therapy and intensity-modulated radiation therapy treatment planning for prostate cancer with flattened beam and flattening filter free linear accelerators. J Appl Clin Med Phys 2017; 18:307-314. [PMID: 28857432 PMCID: PMC5875831 DOI: 10.1002/acm2.12168] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 07/17/2017] [Accepted: 07/20/2017] [Indexed: 12/25/2022] Open
Abstract
This study on patients with localized prostate cancer was set up to investigate valuable differences using flattened beam (FB) and flattening filter free (FFF) mode in the application of intensity-modulated radiotherapy (IMRT) and volumetric-modulated arc therapy (VMAT). For ten patients, four different plans were calculated with Oncentra planning system of Elekta, using Synergy machines: IMRT and VMAT, with and without flattening filter. Homogeneity and conformity indexes, dose to the organs at risk, and measurements of peripheral dose and dosimetric plan verification including record of the delivery times were analyzed and statistically evaluated. The indexes for homogeneity and conformity (CTV and PTV) are either advantageous or not significantly different for FFF compared to FB with one minor exception. Regarding the doses to the organs at risk and the measured peripheral dose, equivalent or lower doses were delivered for FFF than with FB. Furthermore, the delivery times were significantly shorter for FFF. VMAT compared to IMRT reveals benefits or at least equivalent values. VMAT-FFF combines the most advantageous plan quality parameters with the shortest delivery times and reduced peripheral dose and is therefore recommended for the given equipment and cancer localization.
Collapse
Affiliation(s)
- Marius Treutwein
- Department for Radiotherapy, Regensburg University Medical Center, Regensburg, Germany
| | - Matthias Hipp
- Department for Radiotherapy, Regensburg University Medical Center, Regensburg, Germany.,Klinikum St. Marien, Strahlentherapie, Amberg, Germany
| | - Oliver Koelbl
- Department for Radiotherapy, Regensburg University Medical Center, Regensburg, Germany
| | - Barbara Dobler
- Department for Radiotherapy, Regensburg University Medical Center, Regensburg, Germany
| |
Collapse
|
17
|
Dobler B, Obermeier T, Hautmann MG, Khemissi A, Koelbl O. Simultaneous integrated boost therapy of carcinoma of the hypopharynx/larynx with and without flattening filter - a treatment planning and dosimetry study. Radiat Oncol 2017; 12:114. [PMID: 28679448 PMCID: PMC5499025 DOI: 10.1186/s13014-017-0850-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 06/28/2017] [Indexed: 01/26/2023] Open
Abstract
Background The aim of this study was to investigate if the flattening filter free (FFF) irradiation mode of a linear accelerator (linac) is advantageous as compared to the flat beam (FF) irradiation mode in intensity modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT) for carcinoma of the hypopharynx / larynx. Methods Four treatment plans were created for each of 10 patients for an Elekta Synergy linac with Agility collimating device, a dual arc VMAT and a nine field step and shoot IMRT each with and without flattening filter. Plan quality was compared considering target coverage and dose to the organs at risk. All plans were verified by a 2D–ionization-chamber-array and delivery times were compared. Peripheral point doses were determined as a measure of second cancer risk. The Wilcoxon test was used for statistical analysis with a significance level of 0.05. Results Plan quality was similar for all four treatment plans without statistically significant differences of clinical relevance. The clinical goals were met in all plans for the PTV-SIB (V95% > 95%), the spinal cord (D1ccm < 45 Gy) and the brain stem (D1ccm < 48 Gy). For the parotids, the goal of D50% < 30 Gy was met in 70% and 60% of the plans for the left and right parotid respectively, and the V95% of the SIB reached an average of 94%. Delivery times were similar for FF and FFF and significantly decreased by around 70% for VMAT as compared to IMRT. Peripheral doses were significantly reduced by 18% in FFF mode as compared to FF and by 26% for VMAT as compared to IMRT. Lowest peripheral doses were found for VMAT FFF, followed by VMAT FF. Conclusions The FFF mode of a linear accelerator is advantageous for the treatment of hypopharynx/larynx carcinoma only with respect to reduction of second cancer induction in peripheral organs for the combination of Elekta Synergy linacs and Oncentra® External Beam v4.5 treatment planning system. This might be of interest in a therapy with curative intent.
Collapse
Affiliation(s)
- Barbara Dobler
- Department of Radiotherapy, Regensburg University Medical Center, Regensburg, Germany.
| | - Tina Obermeier
- Department of Radiotherapy, Regensburg University Medical Center, Regensburg, Germany
| | - Matthias G Hautmann
- Department of Radiotherapy, Regensburg University Medical Center, Regensburg, Germany
| | - Amine Khemissi
- Department of Radiotherapy, Regensburg University Medical Center, Regensburg, Germany
| | - Oliver Koelbl
- Department of Radiotherapy, Regensburg University Medical Center, Regensburg, Germany
| |
Collapse
|
18
|
Sakka M, Kunzelmann L, Metzger M, Grabenbauer GG. Cardiac dose-sparing effects of deep-inspiration breath-hold in left breast irradiation. Strahlenther Onkol 2017. [DOI: 10.1007/s00066-017-1167-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
|