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Konradsson E, Ericsson Szecsenyi R, Wahlqvist P, Thoft A, Blad B, Bäck SÅ, Ceberg C, Petersson K. Reconfiguring a Plane-Parallel Transmission Ionization Chamber to Extend the Operating Range into the Ultra-High Dose-per-pulse Regime. Radiat Res 2024; 201:252-260. [PMID: 38308528 DOI: 10.1667/rade-23-00177.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Accepted: 01/24/2024] [Indexed: 02/04/2024]
Abstract
This study aims to investigate the feasibility of enhancing the charge collection efficiency (CCE) of a transmission chamber by reconfiguring its design and operation. The goal was to extend the range of dose-per-pulse (DPP) values with no or minimal recombination effects up to the ultra-high dose rate (UHDR) regime. The response of two transmission chambers, with electrode distance of 1 mm and 0.6 mm, respectively, was investigated as a function of applied voltage. The chambers were mounted one-by-one in the electron applicator of a 10 MeV FLASH-modified clinical linear accelerator. The chamber signals were measured as a function of nominal DPP, which was determined at the depth of dose maximum using EBT-XD film in solid water and ranged from 0.6 mGy per pulse to 0.9 Gy per pulse, for both the standard voltage of 320 V and the highest possible safe voltage of 1,200 V. The CCE was calculated and fitted with an empirical logistic function that incorporated the electrode distance and the chamber voltage. The CCE decreased with increased DPP. The CCE at the highest achievable DPP was 24% (36%) at 320 V and 51% (82%) at 1,200 V, for chambers with 1 mm (0.6 mm) electrode distance. For the combination of 1,200 V- and 0.6-mm electrode distance, the CCE was ∼100% for average dose rate up to 70 Gy/s at the depth of dose maximum in the phantom at a source-to-surface distance of 100 cm. Our findings indicate that minor modifications to a plane-parallel transmission chamber can substantially enhance the CCE and extending the chamber's operating range to the UHDR regime. This supports the potential of using transmission chamber-based monitoring solutions for UHDR beams, which could facilitate the delivery of UHDR treatments using an approach similar to conventional clinical delivery.
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Affiliation(s)
- Elise Konradsson
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
| | | | - Pontus Wahlqvist
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Andreas Thoft
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Börje Blad
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Sven Åj Bäck
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Crister Ceberg
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Kristoffer Petersson
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
- Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, United Kingdom
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Konradsson E, Wahlqvist P, Thoft A, Blad B, Bäck S, Ceberg C, Petersson K. Beam control system and output fine-tuning for safe and precise delivery of FLASH radiotherapy at a clinical linear accelerator. Front Oncol 2024; 14:1342488. [PMID: 38304871 PMCID: PMC10830783 DOI: 10.3389/fonc.2024.1342488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Accepted: 01/03/2024] [Indexed: 02/03/2024] Open
Abstract
Introduction We have previously adapted a clinical linear accelerator (Elekta Precise, Elekta AB) for ultra-high dose rate (UHDR) electron delivery. To enhance reliability in future clinical FLASH radiotherapy trials, the aim of this study was to introduce and evaluate an upgraded beam control system and beam tuning process for safe and precise UHDR delivery. Materials and Methods The beam control system is designed to interrupt the beam based on 1) a preset number of monitor units (MUs) measured by a monitor detector, 2) a preset number of pulses measured by a pulse-counting diode, or 3) a preset delivery time. For UHDR delivery, an optocoupler facilitates external control of the accelerator's thyratron trigger pulses. A beam tuning process was established to maximize the output. We assessed the stability of the delivery, and the independent interruption capabilities of the three systems (monitor detector, pulse counter, and timer). Additionally, we explored a novel approach to enhance dosimetric precision in the delivery by synchronizing the trigger pulse with the charging cycle of the pulse forming network (PFN). Results Improved beam tuning of gun current and magnetron frequency resulted in average dose rates at the dose maximum at isocenter distance of >160 Gy/s or >200 Gy/s, with or without an external monitor chamber in the beam path, respectively. The delivery showed a good repeatability (standard deviation (SD) in total film dose of 2.2%) and reproducibility (SD in film dose of 2.6%). The estimated variation in DPP resulted in an SD of 1.7%. The output in the initial pulse depended on the PFN delay time. Over the course of 50 measurements employing PFN synchronization, the absolute percentage error between the delivered number of MUs calculated by the monitor detector and the preset MUs was 0.8 ± 0.6% (mean ± SD). Conclusion We present an upgraded beam control system and beam tuning process for safe and stable UHDR electron delivery of hundreds of Gy/s at isocenter distance at a clinical linac. The system can interrupt the beam based on monitor units and utilize PFN synchronization for improved dosimetric precision in the dose delivery, representing an important advancement toward reliable clinical FLASH trials.
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Affiliation(s)
- Elise Konradsson
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Pontus Wahlqvist
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Andreas Thoft
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Börje Blad
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Sven Bäck
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Crister Ceberg
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Kristoffer Petersson
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
- Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, United Kingdom
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Liljedahl E, Konradsson E, Linderfalk K, Gustafsson E, Petersson K, Ceberg C, Redebrandt HN. Comparable survival in rats with intracranial glioblastoma irradiated with single-fraction conventional radiotherapy or FLASH radiotherapy. Front Oncol 2024; 13:1309174. [PMID: 38322292 PMCID: PMC10845047 DOI: 10.3389/fonc.2023.1309174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Accepted: 12/22/2023] [Indexed: 02/08/2024] Open
Abstract
Background Radiotherapy increases survival in patients with glioblastoma. However, the prescribed dose is limited by unwanted side effects on normal tissue. Previous experimental studies have shown that FLASH radiotherapy (FLASH-RT) can reduce these side effects. Still, it is important to establish an equal anti-tumor efficacy comparing FLASH-RT to conventional radiotherapy (CONV-RT). Methods Fully immunocompetent Fischer 344 rats with the GFP-positive NS1 intracranial glioblastoma model were irradiated with CONV-RT or FLASH-RT in one fraction of 20 Gy, 25 Gy or 30 Gy. Animals were monitored for survival and acute dermal side effects. The brains were harvested upon euthanasia and tumors were examined post mortem. Results Survival was significantly increased in animals irradiated with CONV-RT and FLASH-RT at 20 Gy and 25 Gy compared to control animals. The longest survival was reached in animals irradiated with FLASH-RT and CONV-RT at 25 Gy. Irradiation at 30 Gy did not lead to increased survival, despite smaller tumors. Tumor size correlated inversely with irradiation dose, both in animals treated with CONV-RT and FLASH-RT. Acute dermal side effects were mild, but only a small proportion of the animals were alive for evaluation of those side effects. Conclusion The dose response was similar for CONV-RT and FLASH-RT in the present model. Tumor size upon the time of euthanasia correlated inversely with the irradiation dose.
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Affiliation(s)
- Emma Liljedahl
- The Rausing Laboratory, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Elise Konradsson
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Karin Linderfalk
- The Rausing Laboratory, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Emma Gustafsson
- The Rausing Laboratory, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Kristoffer Petersson
- Department of Oncology, Medical Research Council Oxford Institute for Radiation Oncology, University of Oxford, Oxford, United Kingdom
- Radiation Physics, Department of Haematology, Oncology and Radiation Physics, Skåne University Hospital, Lund University, Lund, Sweden
| | - Crister Ceberg
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Henrietta Nittby Redebrandt
- The Rausing Laboratory, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden
- Department of Neurosurgery, Skåne University Hospital, Lund, Sweden
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Konradsson E, Szecsenyi RE, Adrian G, Coskun M, Børresen B, Arendt ML, Erhart K, Bäck SÅ, Petersson K, Ceberg C. Evaluation of intensity-modulated electron FLASH radiotherapy in a clinical setting using veterinary cases. Med Phys 2023; 50:6569-6579. [PMID: 37696040 DOI: 10.1002/mp.16737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 08/08/2023] [Accepted: 08/29/2023] [Indexed: 09/13/2023] Open
Abstract
PURPOSE The increased normal tissue tolerance for FLASH radiotherapy (FLASH-RT), as compared to conventional radiotherapy, was first observed in ultra-high dose rate electron beams. Initial clinical trials in companion animals have revealed a high risk of developing osteoradionecrosis following high-dose single-fraction electron FLASH-RT, which may be related to inhomogeneities in the dose distribution. In the current study, we aim to evaluate the possibilities of intensity-modulated electron FLASH-RT in a clinical setting to ensure a homogeneous dose distribution in future veterinary and human clinical trials. METHODS Our beam model in the treatment planning system electronRT (.decimal, LLC, Sanford, FL, USA) was based on a 10-MeV electron beam from a clinical linear accelerator used to treat veterinary patients with FLASH-RT in a clinical setting. In electronRT, the beam can be intensity-modulated using tungsten island blocks in the electron block cutout, and range-modulated using a customized bolus with variable thickness. Modulations were first validated in a heterogeneous phantom by comparing measured and calculated dose distributions. To evaluate the impact of intensity modulation in superficial single-fraction FLASH-RT, a treatment planning study was conducted, including eight canine cancer patient cases with simulated tumors in the head-and-neck region. For each case, treatment plans with and without intensity modulation were created for a uniform bolus and a range-modulating bolus. Treatment plans were evaluated using a target dose homogeneity index (HI), a conformity index (CI), the near-maximum dose outside the target (D 2 % , Body - PTV ${D_{2{\mathrm{\% }},{\mathrm{\ Body}} - {\mathrm{PTV}}}}$ ), and the near-minimum dose to the target (D 98 % ${D_{98\% }}$ ). RESULTS By adding intensity modulation to plans with a uniform bolus, the HI could be improved (p = 0.017). The combination of a range-modulating bolus and intensity modulation provided a further significant improvement of the HI as compared to using intensity modulation in combination with a uniform bolus (p = 0.036). The range-modulating bolus also improved the CI compared to using a uniform bolus, both with an open beam (p = 0.046) and with intensity modulation (p = 0.018), as well as increased theD 98 % ${D_{98\% }}$ (p = 0.036 with open beam and p = 0.05 with intensity modulation) and reduced the medianD 2 % , Body - PTV ${D_{2\% ,{\mathrm{\ Body}} - {\mathrm{PTV}}}}$ (not significant). CONCLUSIONS By using intensity-modulated electron FLASH-RT in combination with range-modulating bolus, the target dose homogeneity and conformity in canine patients with simulated tumors in complex areas in the head-and-neck region could be improved. By utilizing this technique, we hope to decrease the dose outside the target volume and avoid hot spots in future clinical electron FLASH-RT studies, thereby reducing the risk of radiation-induced toxicity.
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Affiliation(s)
- Elise Konradsson
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Rebecka Ericsson Szecsenyi
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
- Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Gabriel Adrian
- Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
- Division of Oncology and Pathology, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Mizgin Coskun
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
- Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Betina Børresen
- Department of Veterinary Clinical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Maja Louise Arendt
- Department of Veterinary Clinical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | | | - Sven Åj Bäck
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
- Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Kristoffer Petersson
- Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
- Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, UK
| | - Crister Ceberg
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
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Børresen B, Arendt ML, Konradsson E, Bastholm Jensen K, Bäck SÅJ, Munck af Rosenschöld P, Ceberg C, Petersson K. Evaluation of single-fraction high dose FLASH radiotherapy in a cohort of canine oral cancer patients. Front Oncol 2023; 13:1256760. [PMID: 37766866 PMCID: PMC10520273 DOI: 10.3389/fonc.2023.1256760] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 08/24/2023] [Indexed: 09/29/2023] Open
Abstract
Background FLASH radiotherapy (RT) is a novel method for delivering ionizing radiation, which has been shown in preclinical studies to have a normal tissue sparing effect and to maintain anticancer efficacy as compared to conventional RT. Treatment of head and neck tumors with conventional RT is commonly associated with severe toxicity, hence the normal tissue sparing effect of FLASH RT potentially makes it especially advantageous for treating oral tumors. In this work, the objective was to study the adverse effects of dogs with spontaneous oral tumors treated with FLASH RT. Methods Privately-owned dogs with macroscopic malignant tumors of the oral cavity were treated with a single fraction of ≥30Gy electron FLASH RT and subsequently followed for 12 months. A modified conventional linear accelerator was used to deliver the FLASH RT. Results Eleven dogs were enrolled in this prospective study. High grade adverse effects were common, especially if bone was included in the treatment field. Four out of six dogs, who had bone in their treatment field and lived at least 5 months after RT, developed osteoradionecrosis at 3-12 months post treatment. The treatment was overall effective with 8/11 complete clinical responses and 3/11 partial responses. Conclusion This study shows that single-fraction high dose FLASH RT was generally effective in this mixed group of malignant oral tumors, but the risk of osteoradionecrosis is a serious clinical concern. It is possible that the risk of osteonecrosis can be mitigated through fractionation and improved dose conformity, which needs to be addressed before moving forward with clinical trials in human cancer patients.
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Affiliation(s)
- Betina Børresen
- Department of Veterinary Clinical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Maja L. Arendt
- Department of Veterinary Clinical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Elise Konradsson
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
| | | | - Sven ÅJ. Bäck
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Per Munck af Rosenschöld
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Crister Ceberg
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Kristoffer Petersson
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
- Department of Oncology, Oxford Institute for Radiation Oncology, University of Oxford, Oxford, United Kingdom
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Mannerberg A, Konradsson E, Kügele M, Edvardsson A, Kadhim M, Ceberg C, Peterson K, Thomasson HM, Arendt ML, Børresen B, Jensen KB, Ceberg S. Surface guided electron FLASH radiotherapy for canine cancer patients. Med Phys 2023. [PMID: 37190907 DOI: 10.1002/mp.16453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 04/05/2023] [Accepted: 04/24/2023] [Indexed: 05/17/2023] Open
Abstract
BACKGROUND During recent years FLASH radiotherapy (FLASH-RT) has shown promising results in radiation oncology, with the potential to spare normal tissue while maintaining the antitumor effects. The high speed of the FLASH-RT delivery increases the need for fast and precise motion monitoring to avoid underdosing the target. Surface guided radiotherapy (SGRT) uses surface imaging (SI) to render a 3D surface of the patient. SI provides real-time motion monitoring and has a large scanning field of view, covering off-isocentric positions. However, SI has so far only been used for human patients with conventional setup and treatment. PURPOSE The aim of this study was to investigate the performance of SI as a motion management tool during electron FLASH-RT of canine cancer patients. METHODS To evaluate the SI system's ability to render surfaces of fur, three fur-like blankets in white, grey, and black were used to imitate the surface of canine patients and the camera settings were optimized for each blanket. Phantom measurements using the fur blankets were carried out, simulating respiratory motion and sudden shift. Respiratory motion was simulated using the QUASAR Respiratory Motion Phantom with the fur blankets placed on the phantom platform, which moved 10 mm vertically with a simulated respiratory period of 4 s. Sudden motion was simulated with an in-house developed phantom, consisting of a platform which was moved vertically in a stepwise motion at a chosen frequency. For sudden measurements, 1, 2, 3, 4, 5, 6, 7, and 10 Hz were measured. All measurements were both carried out at the conventional source-to-surface distance (SSD) of 100 cm, and in the locally used FLASH-RT setup at SSD = 70 cm. The capability of the SI system to reproduce the simulated motion and the sampling time were evaluated. As an initial step towards clinical implementation, the feasibility of SI for surface guided FLASH-RT was evaluated for 11 canine cancer patients. RESULTS The SI camera was capable of rendering surfaces for all blankets. The deviation between simulated and measured mean peak-to-peak breathing amplitude was within 0.6 mm for all blankets. The sampling time was generally higher for the black fur than for the white and grey fur, for the measurement of both respiratory and sudden motion. The SI system could measure sudden motion within 62.5 ms and detect motion with a frequency of 10 Hz. The feasibility study of the canine patients showed that the SI system could be an important tool to ensure patient safety. By using this system we could ensure and document that 10 out of 11 canine patients had a total vector offset from the reference setup position <2 mm immediately before and after irradiation. CONCLUSIONS We have shown that SI can be used for surface guided FLASH-RT of canine patients. The SI system is currently not fast enough to interrupt a FLASH-RT beam while irradiating but with the short sampling time sudden motion can be detected. The beam can therefore be held just prior to irradiation, preventing treatment errors such as underdosing the target.
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Affiliation(s)
| | | | - Malin Kügele
- Medical Radiation Physics, Lund University, Lund, Sweden
- Department of Hematology- Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Anneli Edvardsson
- Medical Radiation Physics, Lund University, Lund, Sweden
- Department of Hematology- Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Mustafa Kadhim
- Department of Hematology- Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Crister Ceberg
- Medical Radiation Physics, Lund University, Lund, Sweden
| | - Kristoffer Peterson
- Department of Hematology- Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
- Department of Oncology, MRC Oxford Institute for Radiation Oncology, University of Oxford, Oxford, UK
| | - Hanna-Maria Thomasson
- Department of Hematology- Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Maja L Arendt
- Department of Veterinary Clinical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Betina Børresen
- Department of Veterinary Clinical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | | | - Sofie Ceberg
- Medical Radiation Physics, Lund University, Lund, Sweden
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Liljedahl E, Konradsson E, Gustafsson E, Jonsson KF, Olofsson JK, Osther K, Ceberg C, Redebrandt HN. Combined anti-C1-INH and radiotherapy against glioblastoma. BMC Cancer 2023; 23:106. [PMID: 36717781 PMCID: PMC9887755 DOI: 10.1186/s12885-023-10583-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Accepted: 01/25/2023] [Indexed: 02/01/2023] Open
Abstract
BACKGROUND A more effective immune response against glioblastoma is needed in order to achieve better tumor control. Radiotherapy can induce anti-tumor mediated immune reactions, in addition to its dose response effects. The complement system can function as a bridge between innate and adaptive immune responses. Combining radiotherapy and complement activating therapy is theoretically interesting. METHODS Radiotherapy at 8 Gy × 2 was combined with treatment against C1-inhibitor (C1-INH), a potent inhibitor of activation of the classical pathway of the complement system. Anti-C1-INH was delivered as intratumoral injections. Fully immunocompetent Fischer 344 rats with NS1 glioblastoma tumors were treated. Survival was monitored as primary outcome. Models with either intracranial or subcutaneous tumors were evaluated separately. RESULTS In the intracranial setting, irradiation could prolong survival, but there was no additional survival gain as a result of anti-C1-INH treatment. In animals with subcutaneous tumors, combined radio-immunotherapy with anti-C1-INH and irradiation at 8 Gy × 2 significantly prolonged survival compared to control animals, whereas irradiation or anti-C1-INH treatment as single therapies did not lead to significantly increased survival compared to control animals. CONCLUSIONS Anti-C1-INH treatment could improve the efficacy of irradiation delivered at sub-therapeutic doses and delay tumor growth in the subcutaneous tumor microenvironment. In the intracranial setting, the doses of anti-C1-INH were not enough to achieve any survival effect in the present setting.
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Affiliation(s)
- Emma Liljedahl
- grid.4514.40000 0001 0930 2361The Rausing Laboratory, Division of Neurosurgery, Department of Clinical Sciences, Lund University, BMC D10, 221 84 Lund, Sweden
| | - Elise Konradsson
- grid.4514.40000 0001 0930 2361Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Emma Gustafsson
- grid.4514.40000 0001 0930 2361The Rausing Laboratory, Division of Neurosurgery, Department of Clinical Sciences, Lund University, BMC D10, 221 84 Lund, Sweden
| | - Karolina Förnvik Jonsson
- grid.4514.40000 0001 0930 2361The Rausing Laboratory, Division of Neurosurgery, Department of Clinical Sciences, Lund University, BMC D10, 221 84 Lund, Sweden
| | - Jill K. Olofsson
- grid.5254.60000 0001 0674 042XDepartment for Geosciences and Natural Resource Management, University of Copenhagen, Copenhagen, Denmark
| | - Kurt Osther
- grid.4514.40000 0001 0930 2361The Rausing Laboratory, Division of Neurosurgery, Department of Clinical Sciences, Lund University, BMC D10, 221 84 Lund, Sweden
| | - Crister Ceberg
- grid.4514.40000 0001 0930 2361Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Henrietta Nittby Redebrandt
- grid.4514.40000 0001 0930 2361The Rausing Laboratory, Division of Neurosurgery, Department of Clinical Sciences, Lund University, BMC D10, 221 84 Lund, Sweden ,grid.411843.b0000 0004 0623 9987Department of Neurosurgery, Skåne University Hospital, Lund, Sweden
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Konradsson E, Liljedahl E, Gustafsson E, Adrian G, Beyer S, Ilaahi SE, Petersson K, Ceberg C, Nittby Redebrandt H. Comparable Long-Term Tumor Control for Hypofractionated FLASH Versus Conventional Radiation Therapy in an Immunocompetent Rat Glioma Model. Adv Radiat Oncol 2022; 7:101011. [PMID: 36092986 PMCID: PMC9449779 DOI: 10.1016/j.adro.2022.101011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 06/20/2022] [Indexed: 11/29/2022] Open
Abstract
Purpose To ensure a clinical translation of FLASH radiation therapy (FLASH-RT) for a specific tumor type, studies on tumor control and toxicity within the same biological system are needed. In this study, our objective was to evaluate tumor control and toxicity for hypofractionated FLASH-RT and conventional radiation therapy (CONV-RT) in an immunocompetent rat glioma model. Methods and Materials Fisher 344 rats (N = 68) were inoculated subcutaneously with NS1 glioma cells and randomized into groups (n = 9-10 per group). CONV-RT (∼8 Gy/min) or FLASH-RT (70-90 Gy/s) was administered in 3 fractions of either 8 Gy, 12.5 Gy, or 15 Gy using a 10-MeV electron beam. The maximum tumor diameter was measured weekly, and overall survival was determined until day 100. Long-term tumor control was defined as no evident tumor on day 100. Animals were evaluated for acute dermal side effects at 2 to 5 weeks after completed RT and for late dermal side effects at 3 months after initiation of treatment. Results Survival was significantly increased in all irradiated groups compared with control animals (P < .001). In general, irradiated tumors started to shrink at 1 week post-completed RT. In 40% (23 of 58) of the irradiated animals, long-term tumor control was achieved. Radiation-induced skin toxic effects were mild and consisted of hair loss, erythema, and dry desquamation. No severe toxic effect was observed. There was no significant difference between FLASH-RT and CONV-RT in overall survival, acute side effects, or late side effects for any of the dose levels. Conclusions This study shows that hypofractionated FLASH-RT results in long-term tumor control rates similar to those of CONV-RT for the treatment of large subcutaneous glioblastomas in immunocompetent rats. Neither treatment technique induced severe skin toxic effects. Consequently, no significant difference in toxicity could be resolved, suggesting that higher doses may be required to detect a FLASH sparing of skin.
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Affiliation(s)
- Elise Konradsson
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Emma Liljedahl
- Rausing Laboratory, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Emma Gustafsson
- Rausing Laboratory, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Gabriel Adrian
- Division of Oncology and Pathology, Department of Clinical Sciences, Skåne University Hospital, Lund University, Lund, Sweden
- Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Sarah Beyer
- Division of Oncology and Pathology, Department of Clinical Sciences, Skåne University Hospital, Lund University, Lund, Sweden
| | - Suhayb Ehsaan Ilaahi
- Rausing Laboratory, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Kristoffer Petersson
- Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
- MRC Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, United Kingdom
| | - Crister Ceberg
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Henrietta Nittby Redebrandt
- Rausing Laboratory, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden
- Department of Neurosurgery, Skåne University Hospital, Lund, Sweden
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Liljedahl E, Konradsson E, Gustafsson E, Jonsson KF, Olofsson JK, Ceberg C, Redebrandt HN. Long-term anti-tumor effects following both conventional radiotherapy and FLASH in fully immunocompetent animals with glioblastoma. Sci Rep 2022; 12:12285. [PMID: 35853933 PMCID: PMC9296533 DOI: 10.1038/s41598-022-16612-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 07/12/2022] [Indexed: 12/13/2022] Open
Abstract
Radiotherapy can induce an immunological response. One limiting factor is side effects on normal tissue. Using FLASH radiotherapy, side effects could possibly be reduced. The efficacy of FLASH in relation to conventional radiotherapy (CONV-RT) has not been extensively explored in fully immunocompetent animals. Fully immunocompetent Fischer 344 rats were inoculated with NS1 glioblastoma cells subcutaneously or intracranially. Radiotherapy was delivered with FLASH or CONV-RT at 8 Gy × 2 (subcutaneous tumors) and 12.5 Gy × 2 (intracranial tumors). Cured animals were re-challenged in order to explore long-term anti-tumor immunity. Serum analytes and gene expression were explored. The majority of animals with subcutaneous tumors were cured when treated with FLASH or CONV-RT at 8 Gy × 2. Cured animals could reject tumor re-challenge. TIMP-1 in serum was reduced in animals treated with FLASH 8 Gy × 2 compared to control animals. Animals with intracranial tumors survived longer when treated with FLASH or CONV-RT at 12.5 Gy × 2, but cure was not reached. CONV-RT and FLASH were equally effective in fully immunocompetent animals with glioblastoma. Radiotherapy was highly efficient in the subcutaneous setting, leading to cure and long-term immunity in the majority of the animals.
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Affiliation(s)
- Emma Liljedahl
- The Rausing Laboratory, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Elise Konradsson
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Emma Gustafsson
- The Rausing Laboratory, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Karolina Förnvik Jonsson
- The Rausing Laboratory, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Jill K Olofsson
- Department for Geosciences and Natural Resource Management, University of Copenhagen, Copenhagen, Denmark
| | - Crister Ceberg
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Henrietta Nittby Redebrandt
- The Rausing Laboratory, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden. .,Department of Neurosurgery, Skåne University Hospital, Rausing Laboratory, Lund University, BMC D10, 221 84, Lund, Sweden.
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10
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Mannerberg A, Konradsson E, Edvardsson A, Kügele M, Kadhim M, Ceberg C, Petersson K, Thomasson H, Arendt M, Børresen B, Bastholm Jensen K. PO-1711 Accurate FLASH delivery requires motion monitoring – SGRT is a feasible option for canine patients. Radiother Oncol 2022. [DOI: 10.1016/s0167-8140(22)03675-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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11
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Khazaei S, Nilsson L, Adrian G, Tryggvadottir H, Konradsson E, Borgquist S, Isaksson K, Ceberg C, Jernström H. Impact of combining vitamin C with radiation therapy in human breast cancer: does it matter? Oncotarget 2022; 13:439-453. [PMID: 35222809 PMCID: PMC8863110 DOI: 10.18632/oncotarget.28204] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Accepted: 02/14/2022] [Indexed: 11/25/2022] Open
Affiliation(s)
- Somayeh Khazaei
- Division of Oncology, Clinical Sciences in Lund, Lund University and Skåne University Hospital, Lund, Sweden
- Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Linn Nilsson
- Division of Oncology, Clinical Sciences in Lund, Lund University and Skåne University Hospital, Lund, Sweden
- Department of Medical Physics and Engineering, Växjö Central Hospital and Department of Research and Development, Region Kronoberg, Växjö, Sweden
| | - Gabriel Adrian
- Division of Oncology, Clinical Sciences in Lund, Lund University and Skåne University Hospital, Lund, Sweden
- Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Helga Tryggvadottir
- Division of Oncology, Clinical Sciences in Lund, Lund University and Skåne University Hospital, Lund, Sweden
- Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Elise Konradsson
- Department of Clinical Sciences in Lund, Medical Radiation Physics, Lund University, Lund, Sweden
| | - Signe Borgquist
- Division of Oncology, Clinical Sciences in Lund, Lund University and Skåne University Hospital, Lund, Sweden
- Department of Oncology, Aarhus University and Aarhus University Hospital, Aarhus, Denmark
| | - Karolin Isaksson
- Division of Surgery, Department of Clinical Sciences in Lund, Lund University, Lund, Sweden
- Department of Surgery, Kristianstad Hospital, Kristianstad, Sweden
| | - Crister Ceberg
- Department of Clinical Sciences in Lund, Medical Radiation Physics, Lund University, Lund, Sweden
| | - Helena Jernström
- Division of Oncology, Clinical Sciences in Lund, Lund University and Skåne University Hospital, Lund, Sweden
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12
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Petersson K, Konradsson E, Arendt M, Jensen KB, Børresen B, Kristensen A, Hansen A, Af Rosenschöld PM, Bäck S, Ceberg C. FLASH in the Clinic Track FLASH RADIOTHERAPY TREATMENT OF CANINE PATIENTS. Phys Med 2022. [DOI: 10.1016/s1120-1797(22)01446-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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13
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Adrian G, Brus A, Konradsson E, Eriksson S, Andresen T, Petersson K, Carneiro A, Hansen A, Ceberg C. FLASH Mechanisms Track (Oral Presentations) FLASH SPARING OF MELANOMA CELLS IN VITRO AND IN VIVO. Phys Med 2022. [DOI: 10.1016/s1120-1797(22)01461-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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14
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Konradsson E, Lempart M, Blad B, Petersson K, Ceberg C. ION COLLECTION EFFICIENCY IN A PLANE-PARALLEL TRANSMISSION CHAMBER OPERATED AT HIGH POLARIZING VOLTAGES IN A PULSED ELECTRON BEAM. Phys Med 2022. [DOI: 10.1016/s1120-1797(22)01665-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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15
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Ericsson-Szecsenyi R, Zhang G, Redler G, Feygelman V, Rosenberg S, Latifi K, Ceberg C, Moros EG. Robustness Assessment of Images From a 0.35T Scanner of an Integrated MRI-Linac: Characterization of Radiomics Features in Phantom and Patient Data. Technol Cancer Res Treat 2022; 21:15330338221099113. [PMID: 35521966 PMCID: PMC9083059 DOI: 10.1177/15330338221099113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Purpose: Radiomics entails the extraction of quantitative imaging biomarkers (or radiomics features) hypothesized to provide additional pathophysiological and/or clinical information compared to qualitative visual observation and interpretation. This retrospective study explores the variability of radiomics features extracted from images acquired with the 0.35 T scanner of an integrated MRI-Linac. We hypothesized we would be able to identify features with high repeatability and reproducibility over various imaging conditions using phantom and patient imaging studies. We also compared findings from the literature relevant to our results. Methods: Eleven scans of a Magphan® RT phantom over 13 months and 11 scans of a ViewRay Daily QA phantom over 11 days constituted the phantom data. Patient datasets included 50 images from ten anonymized stereotactic body radiation therapy (SBRT) pancreatic cancer patients (50 Gy in 5 fractions). A True Fast Imaging with Steady-State Free Precession (TRUFI) pulse sequence was selected, using a voxel resolution of 1.5 mm × 1.5 mm × 1.5 mm and 1.5 mm × 1.5 mm × 3.0 mm for phantom and patient data, respectively. A total of 1087 shape-based, first, second, and higher order features were extracted followed by robustness analysis. Robustness was assessed with the Coefficient of Variation (CoV < 5%). Results: We identified 130 robust features across the datasets. Robust features were found within each category, except for 2 second-order sub-groups, namely, Gray Level Size Zone Matrix (GLSZM) and Neighborhood Gray Tone Difference Matrix (NGTDM). Additionally, several robust features agreed with findings from other stability assessments or predictive performance studies in the literature. Conclusion: We verified the stability of the 0.35 T scanner of an integrated MRI-Linac for longitudinal radiomics phantom studies and identified robust features over various imaging conditions. We conclude that phantom measurements can be used to identify robust radiomics features. More stability assessment research is warranted.
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Affiliation(s)
| | - Geoffrey Zhang
- Radiation Oncology Department, 25301H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA
| | - Gage Redler
- Radiation Oncology Department, 25301H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA
| | - Vladimir Feygelman
- Radiation Oncology Department, 25301H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA
| | - Stephen Rosenberg
- Radiation Oncology Department, 25301H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA
| | - Kujtim Latifi
- Radiation Oncology Department, 25301H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA
| | - Crister Ceberg
- Department of Medical Radiation Physics, Clinical Sciences, 5193Lund University, Lund, Sweden
| | - Eduardo G Moros
- Radiation Oncology Department, 25301H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA
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16
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Konradsson E, Arendt M, Jensen K, Thomasson H, Børresen B, Petersson K, Ceberg C. Intracavitary Electron FLASH Radiotherapy in a Canine Cancer Patient With Oral Malignant Melanoma. Int J Radiat Oncol Biol Phys 2021. [DOI: 10.1016/j.ijrobp.2021.07.097] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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17
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Mannerberg A, Konradsson E, Kügele M, Edvardsson A, Ceberg C, Thomasson H, Arendt M, Bastholm Jensen K, Ceberg S. PO-1767 Surface guided FLASH radiotherapy. Radiother Oncol 2021. [DOI: 10.1016/s0167-8140(21)08218-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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18
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Adrian G, Konradsson E, Beyer S, Wittrup A, Butterworth KT, McMahon SJ, Ghita M, Petersson K, Ceberg C. Cancer Cells Can Exhibit a Sparing FLASH Effect at Low Doses Under Normoxic In Vitro-Conditions. Front Oncol 2021; 11:686142. [PMID: 34395253 PMCID: PMC8358772 DOI: 10.3389/fonc.2021.686142] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 07/07/2021] [Indexed: 01/15/2023] Open
Abstract
Background Irradiation with ultra-high dose rate (FLASH) has been shown to spare normal tissue without hampering tumor control in several in vivo studies. Few cell lines have been investigated in vitro, and previous results are inconsistent. Assuming that oxygen depletion accounts for the FLASH sparing effect, no sparing should appear for cells irradiated with low doses in normoxia. Methods Seven cancer cell lines (MDA-MB-231, MCF7, WiDr, LU-HNSCC4, HeLa [early passage and subclone]) and normal lung fibroblasts (MRC-5) were irradiated with doses ranging from 0 to 12 Gy using FLASH (≥800 Gy/s) or conventional dose rates (CONV, 14 Gy/min), with a 10 MeV electron beam from a clinical linear accelerator. Surviving fraction (SF) was determined with clonogenic assays. Three cell lines were further studied for radiation-induced DNA-damage foci using a 53BP1-marker and for cell cycle synchronization after irradiation. Results A tendency of increased survival following FLASH compared with CONV was suggested for all cell lines, with significant differences for 4/7 cell lines. The magnitude of the FLASH-sparing expressed as a dose-modifying factor at SF=0.1 was around 1.1 for 6/7 cell lines and around 1.3 for the HeLasubclone. Similar cell cycle distributions and 53BP1-foci numbers were found comparing FLASH to CONV. Conclusion We have found a FLASH effect appearing at low doses under normoxic conditions for several cell lines in vitro. The magnitude of the FLASH effect differed between the cell lines, suggesting inherited biological susceptibilities for FLASH irradiation.
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Affiliation(s)
- Gabriel Adrian
- Division of Oncology and Pathology, Clinical Sciences, Skåne University Hospital, Lund University, Lund, Sweden.,Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Elise Konradsson
- Department of Medical Radiation Physics, Clinical Sciences, Lund University, Lund, Sweden
| | - Sarah Beyer
- Division of Oncology and Pathology, Clinical Sciences, Skåne University Hospital, Lund University, Lund, Sweden
| | - Anders Wittrup
- Division of Oncology and Pathology, Clinical Sciences, Skåne University Hospital, Lund University, Lund, Sweden.,Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden.,Wallenberg Center for Molecular Medicine, Lund, Sweden
| | - Karl T Butterworth
- Patrick G. Johnston Centre for Cancer Research, Queen's University Belfast, Belfast, United Kingdom
| | - Stephen J McMahon
- Patrick G. Johnston Centre for Cancer Research, Queen's University Belfast, Belfast, United Kingdom
| | - Mihaela Ghita
- Patrick G. Johnston Centre for Cancer Research, Queen's University Belfast, Belfast, United Kingdom
| | - Kristoffer Petersson
- Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden.,Medical Research Council Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, United Kingdom
| | - Crister Ceberg
- Department of Medical Radiation Physics, Clinical Sciences, Lund University, Lund, Sweden
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19
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Konradsson E, Arendt ML, Bastholm Jensen K, Børresen B, Hansen AE, Bäck S, Kristensen AT, Munck Af Rosenschöld P, Ceberg C, Petersson K. Establishment and Initial Experience of Clinical FLASH Radiotherapy in Canine Cancer Patients. Front Oncol 2021; 11:658004. [PMID: 34055624 PMCID: PMC8155542 DOI: 10.3389/fonc.2021.658004] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Accepted: 04/26/2021] [Indexed: 01/19/2023] Open
Abstract
FLASH radiotherapy has emerged as a treatment technique with great potential to increase the differential effect between normal tissue toxicity and tumor response compared to conventional radiotherapy. To evaluate the feasibility of FLASH radiotherapy in a relevant clinical setting, we have commenced a feasibility and safety study of FLASH radiotherapy in canine cancer patients with spontaneous superficial solid tumors or microscopic residual disease, using the electron beam of our modified clinical linear accelerator. The setup for FLASH radiotherapy was established using a short electron applicator with a nominal source-to-surface distance of 70 cm and custom-made Cerrobend blocks for collimation. The beam was characterized by measuring dose profiles and depth dose curves for various field sizes. Ten canine cancer patients were included in this initial study; seven patients with nine solid superficial tumors and three patients with microscopic disease. The administered dose ranged from 15 to 35 Gy. To ensure correct delivery of the prescribed dose, film measurements were performed prior to and during treatment, and a Farmer-type ion-chamber was used for monitoring. Treatments were found to be feasible, with partial response, complete response or stable disease recorded in 11/13 irradiated tumors. Adverse events observed at follow-up ranging from 3-6 months were mild and consisted of local alopecia, leukotricia, dry desquamation, mild erythema or swelling. One patient receiving a 35 Gy dose to the nasal planum, had a grade 3 skin adverse event. Dosimetric procedures, safety and an efficient clincal workflow for FLASH radiotherapy was established. The experience from this initial study will be used as a basis for a veterinary phase I/II clinical trial with more specific patient inclusion selection, and subsequently for human trials.
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Affiliation(s)
- Elise Konradsson
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Maja L Arendt
- Department of Veterinary Clinical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | | | - Betina Børresen
- Department of Veterinary Clinical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Anders E Hansen
- Department of Biotherapeutic Engineering and Drug Targeting, DTU Health Tech, Kgs, Technical University of Denmark, Lyngby, Denmark
| | - Sven Bäck
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Annemarie T Kristensen
- Department of Veterinary Clinical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Per Munck Af Rosenschöld
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Crister Ceberg
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Kristoffer Petersson
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden.,Department of Oncology, Oxford Institute for Radiation Oncology, University of Oxford, Oxford, United Kingdom
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20
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Konradsson E, Ceberg C, Lempart M, Blad B, Bäck S, Knöös T, Petersson K. Correction for Ion Recombination in a Built-in Monitor Chamber of a Clinical Linear Accelerator at Ultra-High Dose Rates. Radiat Res 2021; 194:580-586. [PMID: 33348371 DOI: 10.1667/rade-19-00012] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 04/29/2020] [Indexed: 11/03/2022]
Abstract
In the novel and promising radiotherapy technique known as FLASH, ultra-high dose-rate electron beams are used. As a step towards clinical trials, dosimetric advances will be required for accurate dose delivery of FLASH. The purpose of this study was to determine whether a built-in transmission chamber of a clinical linear accelerator can be used as a real-time dosimeter to monitor the delivery of ultra-high-dose-rate electron beams. This was done by modeling the drop-in ion-collection efficiency of the chamber with increasing dose-per-pulse values, so that the ion recombination effect could be considered. The raw transmission chamber signal was extracted from the linear accelerator and its response was measured using radiochromic film at different dose rates/dose-per-pulse values, at a source-to-surface distance of 100 cm. An increase of the polarizing voltage, applied over the transmission chamber, by a factor of 2 and 3, improved the ion-collection efficiency, with corresponding increased efficiency at the highest dose-per-pulse values by a factor 1.4 and 2.2, respectively. The drop-in ion-collection efficiency with increasing dose-per-pulse was accurately modeled using a logistic function fitted to the transmission chamber data. The performance of the model was compared to that of the general theoretical Boag models of ion recombination in ionization chambers. The logistic model was subsequently used to correct for ion recombination at dose rates ranging from conventional to ultra-high, making the transmission chamber useful as a real-time monitor for the dose delivery of FLASH electron beams in a clinical setup.
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Affiliation(s)
- Elise Konradsson
- Medical Radiation Physics, Department of Clinical Science, Lund University, Lund, Sweden
| | - Crister Ceberg
- Medical Radiation Physics, Department of Clinical Science, Lund University, Lund, Sweden
| | - Michael Lempart
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Börje Blad
- Medical Radiation Physics, Department of Clinical Science, Lund University, Lund, Sweden.,Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Sven Bäck
- Medical Radiation Physics, Department of Clinical Science, Lund University, Lund, Sweden.,Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Tommy Knöös
- Medical Radiation Physics, Department of Clinical Science, Lund University, Lund, Sweden.,Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Kristoffer Petersson
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden.,The CRUK/MRC Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, United Kingdom
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21
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Haraldsson A, Stina W, Engellau J, Ceberg C, Bäck S, Ceberg S, Engelholm S, Warsi S, Engström P. PO-0916: Dose-rate dependence in haematological recovery following total marrow irradiation. Radiother Oncol 2020. [DOI: 10.1016/s0167-8140(21)00933-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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22
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Konradsson E, Lempart M, Blad B, Ceberg C, Petersson K. OC-0634: Correction for ion recombination in a built-in monitor chamber at ultra-high dose rates. Radiother Oncol 2020. [DOI: 10.1016/s0167-8140(21)00656-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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23
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Haraldsson A, Ceberg S, Ceberg C, Bäck S, Engelholm S, Engström PE. Surface-guided tomotherapy improves positioning and reduces treatment time: A retrospective analysis of 16 835 treatment fractions. J Appl Clin Med Phys 2020; 21:139-148. [PMID: 32592288 PMCID: PMC7484821 DOI: 10.1002/acm2.12936] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 04/20/2020] [Accepted: 05/07/2020] [Indexed: 01/16/2023] Open
Abstract
PURPOSE In this study, we have quantified the setup deviation and time gain when using fast surface scanning for daily setup/positioning with weekly megavoltage computed tomography (MVCT) and compared it to daily MVCT. METHODS A total of 16 835 treatment fractions were analyzed, treated, and positioned using our TomoTherapy HD (Accuray Inc., Madison, USA) installed with a Sentinel optical surface scanning system (C-RAD Positioning AB, Uppsala, Sweden). Patients were positioned using in-room lasers, surface scanning and MVCT for the first three fractions. For the remaining fractions, in-room laser was used for setup followed by daily surface scanning with MVCT once weekly. The three-dimensional (3D) setup correction for surface scanning was evaluated from the registration between MVCT and the planning CT. The setup correction vector for the in-room lasers was assessed from the surface scanning and the MVCT to planning CT registration. The imaging time was evaluated as the time from imaging start to beam-on. RESULTS We analyzed 894 TomoTherapy treatment plans from 2012 to 2018. Of all the treatment fractions performed with surface scanning, 90 % of the residual errors were within 2.3 mm for CNS (N = 284), 2.9 mm for H&N (N = 254), 8.7 mm for thorax (N = 144) and 10.9 for abdomen (N = 134) patients. The difference in residual error between surface scanning and positioning with in-room lasers was significant (P < 0.005) for all sites. The imaging time was assessed as total imaging time per treatment plan, modality, and treatment site and found that surface scanning significantly reduced patient on-couch time compared to MVCT for all treatment sites (P < 0.005). CONCLUSIONS The results indicate that daily surface scanning with weekly MVCT can be used with the current target margins for H&N, CNS, and thorax, with reduced imaging time.
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Affiliation(s)
- André Haraldsson
- Department Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden.,Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Sofie Ceberg
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Crister Ceberg
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Sven Bäck
- Department Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden.,Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Silke Engelholm
- Department Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Per E Engström
- Department Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
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24
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Stervik L, Pettersson N, Scherman J, Behrens CF, Ceberg C, Engelholm S, Gunnarsson K, Hallqvist A, Nyman J, Persson GF, Pøhl M, Wahlstedt I, Vogelius IR, Bäck A. Analysis of early respiratory-related mortality after radiation therapy of non-small-cell lung cancer: feasibility of automatic data extraction for dose-response studies. Acta Oncol 2020; 59:628-635. [PMID: 32202189 DOI: 10.1080/0284186x.2020.1739331] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Purpose: To examine the feasibility of automatic data extraction from clinical radiation therapy (RT) databases at four hospitals to investigate the impact of mean lung dose (MLD) and age on the risk of early respiratory-related death and early overall death for patients treated with RT for non-small-cell lung cancer (NSCLC).Material and methods: We included adult patients with NSCLC receiving curatively intended RT between 2002 and 2017 at four hospitals. A script was developed to automatically extract RT-related data. The cause of death for patients deceased within 180 days of the start of RT was retrospectively assessed. Using logistic regression, the risks of respiratory-related death and of overall death within 90 and 180 days were investigated using MLD and age as variables.Results: Altogether, 1785 patients were included in the analysis of early overall mortality and 1655 of early respiratory-related mortality. The respiratory-related mortalities within 90 and 180 days were 0.9% (15/1655) and 3.6% (60/1655). The overall mortalities within 90 and 180 days were 2.5% (45/1785) and 10.6% (190/1785). Higher MLD and older age were associated with an increased risk of respiratory-related death within 180 days and overall death within 90 and 180 days (all p<.05). For example, the risk of respiratory-related death within 180 days and their 95% confidence interval for patients aged 65 and 75 years with MLDs of 20 Gy was according to our logistic model 3.8% (2.6-5.0%) and 7.7% (5.5-10%), respectively.Conclusions: Automatic data extraction was successfully used to pool data from four hospitals. MLD and age were associated with the risk of respiratory-related death within 180 days of the start of RT and with overall death within 90 and 180 days. A model quantifying the risk of respiratory-related death within 180 days was formulated.
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Affiliation(s)
- Louise Stervik
- Department of Radiation Physics, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Niclas Pettersson
- Department of Radiation Physics, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Department of Therapeutic Radiation Physics, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Jonas Scherman
- Department of Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Claus F. Behrens
- Department of Oncology, Herlev and Gentofte Hospital, University of Copenhagen, Copenhagen, Denmark
| | - Crister Ceberg
- Department of Medical Radiation Physics, Lund University, Lund, Sweden
| | - Silke Engelholm
- Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Kerstin Gunnarsson
- Department of Oncology, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Andreas Hallqvist
- Department of Oncology, Sahlgrenska University Hospital, Gothenburg, Sweden
- Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Jan Nyman
- Department of Oncology, Sahlgrenska University Hospital, Gothenburg, Sweden
- Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Gitte F. Persson
- Department of Oncology, Herlev and Gentofte Hospital, University of Copenhagen, Copenhagen, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Mette Pøhl
- Department of Oncology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Isak Wahlstedt
- Department of Oncology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Ivan R. Vogelius
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Oncology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Anna Bäck
- Department of Radiation Physics, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Department of Therapeutic Radiation Physics, Sahlgrenska University Hospital, Gothenburg, Sweden
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Ahlstedt J, Konradsson E, Ceberg C, Redebrandt HN. Increased effect of two-fraction radiotherapy in conjunction with IDO1 inhibition in experimental glioblastoma. PLoS One 2020; 15:e0233617. [PMID: 32469935 PMCID: PMC7259656 DOI: 10.1371/journal.pone.0233617] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Accepted: 05/09/2020] [Indexed: 12/24/2022] Open
Abstract
Objectives The aim of the study was to investigate therapeutic efficacy of single- or two-fraction radiotherapy in conjunction with IDO1-inhibition in a syngeneic rat glioblastoma model. IDO is known to cause immunosuppression through breakdown of tryptophan in the tumor microenvironment. Methods Gene expression analyses of IDO in glioblastoma were performed with data from publicly available datasets. Fractionation studies were done on animals to evaluate tumor size, immune cell infiltration of tumors and serum profile on day 18 after tumor inoculation. Survival analyses were done with animals carrying intracranial glioblastomas comparing two-fraction radiotherapy+IDO1-inhibition to controls. IDO inhibition was achieved by administration of 1-methyl tryptophan (1-MT), and radiotherapy (RT) was delivered in doses of 8Gy. Results The expression of IDO1 was increased on gene level in glioblastoma stem cells. Tumor size was significantly reduced in animals treated with 1-MT+RTx 2 (both long and short intervals, i.e. 7 and 4 days between the treatments) as compared to control animals, animals treated with only 1-MT or animals treated with 1-MT+RTx1. Serum levels of IL-1A were significantly altered in all treated animals as compared to control animals. Survival was significantly increased in the animals treated with 1-MT+RTx2 (7-day interval) compared to control animals. Conclusions Addition of two-fraction RT to IDO1 inhibition with 1-MT significantly reduced tumor size in animals with glioblastoma. Survival was significantly increased in animals treated with two-fractioned RT+1-MT as compared to untreated controls increased significantly. Advances in knowledge The currently used combination of only two fractions of radiotherapy and immune therapy is a promising area of research, increasing efficacy compared to single fraction irradiation, while potentially lowering radiation side effects compared to radiation in current clinical practice.
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Affiliation(s)
- Jonatan Ahlstedt
- Division of Neurosurgery, Department of Clinical Sciences, The Rausing Laboratory, Lund University, Lund, Sweden
- * E-mail:
| | - Elise Konradsson
- Department of Clinical Sciences, Medical Radiation Physics, Lund University, Lund, Sweden
| | - Crister Ceberg
- Department of Clinical Sciences, Medical Radiation Physics, Lund University, Lund, Sweden
| | - Henrietta Nittby Redebrandt
- Division of Neurosurgery, Department of Clinical Sciences, The Rausing Laboratory, Lund University, Lund, Sweden
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Ahlstedt J, Förnvik K, Helms G, Salford LG, Ceberg C, Skagerberg G, Redebrandt HN. Growth pattern of experimental glioblastoma. Histol Histopathol 2020; 35:871-886. [PMID: 32022242 DOI: 10.14670/hh-18-207] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Glioblastoma multiforme (GBM) is an aggressive primary brain malignancy with a very poor prognosis. Researchers employ animal models to develop potential therapies. It is important that these models have clinical relevance. This means that old models, propagated for decades in cultures, should be questioned. Parameters to be evaluated include whether animals are immune competent or not, the infiltrative growth pattern of the tumor, tumor volume resulting in symptoms and growth rate. We here describe the growth pattern of an experimental glioblastoma model in detail with GFP positive glioblastoma cells in fully immune competent animals and study tumor growth rate and tumor mass as a function of time from inoculation. We were able to correlate findings made with classical immunohistochemistry and MR findings. The tumor growth rate was fitted by a Gompertz function. The model predicted the time until onset of symptoms for 5000 inoculated cells to 18.7±0.4 days, and the tumor mass at days 10 and 14, which are commonly used as the start of treatment in therapeutic studies, were 5.97±0.62 mg and 29.1±3.0 mg, respectively. We want to raise the question regarding the clinical relevance of the outline of glioblastoma experiments, where treatment is often initiated at a very early stage. The approach presented here could potentially be modified to gain information also from other tumor models.
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Affiliation(s)
- Jonatan Ahlstedt
- Rausing Laboratory, Division of Neurosurgery, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Karolina Förnvik
- Rausing Laboratory, Division of Neurosurgery, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Gunther Helms
- Medical Radiation Physics, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Leif G Salford
- Rausing Laboratory, Division of Neurosurgery, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Crister Ceberg
- Medical Radiation Physics, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Gunnar Skagerberg
- Department of Neurosurgery, Skåne University Hospital in Lund, Lund, Sweden
| | - Henrietta Nittby Redebrandt
- Department of Neurosurgery, Skåne University Hospital in Lund, Lund, Sweden.,Rausing Laboratory, Division of Neurosurgery, Department of Clinical Sciences Lund, Lund University, Lund, Sweden.
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Abstract
OBJECTIVE Recent in vivo results have shown prominent tissue sparing effect of radiotherapy with ultra-high dose rates (FLASH) compared to conventional dose rates (CONV). Oxygen depletion has been proposed as the underlying mechanism, but in vitro data to support this have been lacking. The aim of the current study was to compare FLASH to CONV irradiation under different oxygen concentrations in vitro. METHODS Prostate cancer cells were irradiated at different oxygen concentrations (relative partial pressure ranging between 1.6 and 20%) with a 10 MeV electron beam at a dose rate of either 600 Gy/s (FLASH) or 14 Gy/min (CONV), using a modified clinical linear accelerator. We evaluated the surviving fraction of cells using clonogenic assays after irradiation with doses ranging from 0 to 25 Gy. RESULTS Under normoxic conditions, no differences between FLASH and CONV irradiation were found. For hypoxic cells (1.6%), the radiation response was similar up to a dose of about 5-10 Gy, above which increased survival was shown for FLASH compared to CONV irradiation. The increased survival was shown to be significant at 18 Gy, and the effect was shown to depend on oxygen concentration. CONCLUSION The in vitro FLASH effect depends on oxygen concentration. Further studies to characterize and optimize the use of FLASH in order to widen the therapeutic window are indicated. ADVANCES IN KNOWLEDGE This paper shows in vitro evidence for the role of oxygen concentration underlying the difference between FLASH and CONV irradiation.
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Affiliation(s)
- Gabriel Adrian
- Division of Oncology and Pathology, Clinical Sciences, Skåne University Hospital, Lund University, Lund, Sweden
| | - Elise Konradsson
- Department of Medical Radiation Physics, Clinical Sciences, Lund University, Lund, Sweden
| | - Michael Lempart
- Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Sven Bäck
- Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Crister Ceberg
- Department of Medical Radiation Physics, Clinical Sciences, Lund University, Lund, Sweden
| | - Kristoffer Petersson
- Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
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Vilhelmsson Timmermand O, Strand SE, Ceberg C, Ceder JA. An aggressive RhoC phenotype is associated with relapse after external beam radiation therapy of a prostate cancer xenograft model. J Clin Oncol 2019. [DOI: 10.1200/jco.2019.37.15_suppl.e14748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
e14748 Background: Relapsed treatment resistant prostate cancer remains the second most common cause of male mortality in the western world. New therapies for therapy resistant prostate cancer depend on defining tumor cell sub-populations capable of surviving, reinitiating, and sustaining net growth of the cancer. In this study we focused on RhoC expression in a prostate cancer model after external beam radiation therapy (EBRT). RhoC has earlier been implicated in metastatic processes in most solid tumors. Methods: In mice, established s.c. LNCaP xenografts (n = 12) were irradiated, the beam collimated with lead to restrict it to the xenograft, with X-rays (200 kV, 1 Gymin-1, Gulmay Medical) for an absorbed dose of 15 Gy. Tumor tissue was collected after seven days or after 3-4 weeks when recurrent growth was seen. RhoC, AR, CD166 and Ki67 immunohistochemistry in tumor sections was visualized by using DAB or Peroxidase Green and nuclear red or haematoxylin blue as counter stain. Sections stained for RhoC and Ki67 were quantified with the Halo software (v2.3.2089.34) using the Indica Labs – cytonuclear v1.6 algorithm. The intensity of the RhoC staining was also quantified in a separate set of sections only stained for RhoC. Results: The RhoC staining intensity was significantly higher in relapsed xenografts (P = 0.003). Also, a significant difference in percentage of RhoC expressing cells in the two populations (P = 0.045) with 40.6 ± 5.8% (mean ± SEM) in relapsed tumors as compared to 15.0 ± 8.1% after 7d. The percentage of cells expressing Ki67 was not significantly different (P = 0.477). However, the percentage of double positive cells (Ki67, RhoC) was significantly higher in treated relapsed xenografts (P = 0.042). Further, a subpopulation of RhoC-positive cells were positive for AR and the stem cell marker CD166. Conclusions: Here we show that a subpopulation of proliferating RhoC-positive cells are more prevalent in relapsing PCa xenografts after EBRT, suggesting an aggressive phenotype that is associated with both proliferation and invasiveness. Another subpopulation of RhoC cells was found to express the prostate stem cell marker CD166, suggesting that pathways and properties involved in cellular self-renewal and invasiveness may be responsible for survival and recurrent growth in relapsed prostate tumors.
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Affiliation(s)
| | - Sven-Erik Strand
- Department of Clinical Sciences Lund, Division of Oncology, Lund University, Lund, Sweden
| | - Crister Ceberg
- Department of Clinical Sciences Lund, Division of Medical Radiation Physics, Lund University, Lund, Sweden
| | - Jens Adam Ceder
- Department of Clinical Sciences Lund, Division of Oncology, Lund University, Lund, Sweden
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Lempart M, Blad B, Adrian G, Bäck S, Knöös T, Ceberg C, Petersson K. Modifying a clinical linear accelerator for delivery of ultra-high dose rate irradiation. Radiother Oncol 2019; 139:40-45. [PMID: 30755324 DOI: 10.1016/j.radonc.2019.01.031] [Citation(s) in RCA: 99] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 01/24/2019] [Accepted: 01/25/2019] [Indexed: 12/31/2022]
Abstract
OBJECTIVES The purpose of this study was to modify a clinical linear accelerator, making it capable of electron beam ultra-high dose rate (FLASH) irradiation. Modifications had to be quick, reversible, and without interfering with clinical treatments. METHODS Performed modifications: (1) reduced distance with three setup positions, (2) adjusted/optimized gun current, modulator charge rate and beam steering values for a high dose rate, (3) delivery was controlled with a microcontroller on an electron pulse level, and (4) moving the primary and/or secondary scattering foils from the beam path. RESULTS The variation in dose for a five-pulse delivery was measured to be 1% (using a diode, 4% using film) during 10 minutes after a warm-up procedure, later increasing to 7% (11% using film). A FLASH irradiation dose rate was reached at the cross-hair foil, MLC, and wedge position, with ≥30, ≥80, and ≥300 Gy/s, respectively. Moving the scattering foils resulted in an increased output of ≥120, ≥250, and ≥1000 Gy/s, at the three positions. The beam flatness was 5% at the cross-hair position for a 20 × 20 and a 10 × 10 cm2 area, with and without both scattering foils in the beam. The beam flatness was 10% at the wedge position for a 6 and 2.5 cm diametric area, with and without the scattering foils in the beam path. CONCLUSIONS A clinical accelerator was modified to produce ultra-high dose rates, high enough for FLASH irradiation. Future work aims to fine-tune the dose delivery, using the on-board transmission chamber signal and adjusting the dose-per-pulse.
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Affiliation(s)
- Michael Lempart
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund University, Sweden
| | - Börje Blad
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund University, Sweden
| | - Gabriel Adrian
- Division of Oncology and Pathology, Clinical Sciences, Lund, Skåne University Hospital, Lund University, Sweden
| | - Sven Bäck
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund University, Sweden; Department of Medical Radiation Physics, Clinical Sciences, Lund, Lund University, Sweden
| | - Tommy Knöös
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund University, Sweden; Department of Medical Radiation Physics, Clinical Sciences, Lund, Lund University, Sweden
| | - Crister Ceberg
- Department of Medical Radiation Physics, Clinical Sciences, Lund, Lund University, Sweden
| | - Kristoffer Petersson
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund University, Sweden.
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Edvardsson A, Scherman J, Nilsson MP, Wennberg B, Nordström F, Ceberg C, Ceberg S. Breathing-motion induced interplay effects for stereotactic body radiotherapy of liver tumours using flattening-filter free volumetric modulated arc therapy. ACTA ACUST UNITED AC 2019; 64:025006. [DOI: 10.1088/1361-6560/aaf5d9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Stervik L, Pettersson N, Scherman-Rydhög J, Behrens CF, Ceberg C, Vogelius I, Bäck A. [OA077] Modelling the risk of fatal acute toxicity following radiotherapy of lung cancer. Phys Med 2018. [DOI: 10.1016/j.ejmp.2018.06.149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
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Dalaryd M, Knöös T, Ceberg C. [P190] Investigation of beam quality correction factors for flattening filter free photon beams. Phys Med 2018. [DOI: 10.1016/j.ejmp.2018.06.489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Sunjic S, Ceberg C, Bokulic T. Statistical analysis of the gamma evaluation acceptance criteria: A simulation study of 2D dose distributions under error free conditions. Phys Med 2018; 52:42-47. [PMID: 30139608 DOI: 10.1016/j.ejmp.2018.06.633] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 06/03/2018] [Accepted: 06/15/2018] [Indexed: 11/29/2022] Open
Abstract
PURPOSE To investigate the statistical distribution of the gamma value under error-free conditions, in order to study the relation between the gamma evaluation failure rate and statistically significant deviations in the general situation. METHODS The 2D absorbed dose distribution for 30 clinical head-and-neck IMRT fields were calculated in a QC phantom. For the same fields, dose measurements were simulated by assuming that the calculated value represented the expectation value, and by adding a random spatial uncertainty of 1-9 mm (1SD) and a random dose uncertainty of 1%-3% (1SD). The simulated measurements were then compared to the calculated dose using the gamma evaluation, and the distribution of the failure rate (i.e. the probability of gamma values above unity) was analysed. RESULTS For a wide range of the random measurement uncertainty, a distinct peak in the failure rate distribution was observed. The presence of higher failure rates was associated with large values of the second order derivative of the dose distribution. For spatial uncertainties larger than or equal to the resolution of the dose matrix, and for reasonable dose uncertainties, the median value of the failure rate distribution was fairly constant. CONCLUSIONS Simulations showed, in the general case, that the probability of having a gamma value above unity under error-free conditions was not spatially uniform. We believe that this shortcoming may be partly responsible for the limited ability of the gamma evaluation method to detect errors in clinically relevant situations.
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Affiliation(s)
- Svjetlana Sunjic
- Radiation Safety and Medical Physics Department, University Clinical Centre Sarajevo, Bolnicka 25, 71000 Sarajevo, Bosnia and Herzegovina.
| | - Crister Ceberg
- Division of Medical Radiation Physics, Department of Clinical Sciences Lund, Lund University, 221 85 Lund, Sweden.
| | - Tomislav Bokulic
- Dosimetry Laboratory, Dosimetry and Medical Radiation Physics Section, International Atomic Energy Agency, Friedenstrasse 1, Seibersdorf, Austria.
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Benedek H, Lerner M, Nilsson P, Knöös T, Gunnlaugsson A, Ceberg C. The effect of prostate motion during hypofractionated radiotherapy can be reduced by using flattening filter free beams. Phys Imaging Radiat Oncol 2018; 6:66-70. [PMID: 33458391 PMCID: PMC7807632 DOI: 10.1016/j.phro.2018.05.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 05/04/2018] [Accepted: 05/06/2018] [Indexed: 11/29/2022]
Abstract
Background and purpose Hypofractionated radiotherapy of prostate cancer reduces the overall treatment time but increases the per-fraction beam-on time due to the higher fraction doses. This increased fraction treatment time results in a larger uncertainty of the prostate position. The purpose of this study was to investigate the effect of prostate motion during flattening filter free (FFF) Volumetric Modulated Arc Therapy (VMAT) in ultrahypofractionation of prostate cancer radiotherapy with preserved plan quality compared to conventional flattened beams. Materials and methods Nine prostate patients from the Scandinavian HYPO-RT-PC trial were re-planned using VMAT technique with both conventional and flattening filter free beams. Two fractionation schedules were used, one hypofractionated (42.7 Gy in 7 fractions), and one conventional (78.0 Gy in 39 fractions). Pre-treatment verification measurements were performed on all plans and the treatment time was recorded. Measurements with simulated prostate motion were performed for the plans with the longest treatment times. Results All the 10FFF plans fulfilled the clinical gamma pass rate, 90% (3%, 2 mm), during all simulated prostate motion trajectories. The 10MV plans only fulfilled the clinical pass rate for three of the trajectories. The mean beam-on-time for the hypofractionated plans were reduced from 2.3 min to 1.0 min when using 10FFF compared to 10MV. No clinically relevant differences in dose distribution were identified when comparing the plans with different beam qualities. Conclusion Flattening-filter free VMAT reduces treatment times, limiting the dosimetric effect of organ motion for ultrahypofractionated prostate cancer with preserved plan quality.
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Affiliation(s)
- Hunor Benedek
- Department of Haematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden.,Department of Medical Radiation Physics, Clinical Sciences, Lund University, Lund, Sweden
| | - Minna Lerner
- Department of Haematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Per Nilsson
- Department of Haematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden.,Department of Medical Radiation Physics, Clinical Sciences, Lund University, Lund, Sweden
| | - Tommy Knöös
- Department of Haematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden.,Department of Medical Radiation Physics, Clinical Sciences, Lund University, Lund, Sweden
| | - Adalsteinn Gunnlaugsson
- Department of Haematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Crister Ceberg
- Department of Medical Radiation Physics, Clinical Sciences, Lund University, Lund, Sweden
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Chakwizira A, Ahlstedt J, Nittby Redebrandt H, Ceberg C. Mathematical modelling of the synergistic combination of radiotherapy and indoleamine-2,3-dioxygenase (IDO) inhibitory immunotherapy against glioblastoma. Br J Radiol 2018; 91:20170857. [PMID: 29688039 PMCID: PMC6221783 DOI: 10.1259/bjr.20170857] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Objective: Recent research has shown that combining radiotherapy and immunotherapy can counteract the ability of cancer to evade and suppress the native immune system. To optimise the synergy of the combined therapies, factors such as radiation dose and fractionation must be considered, alongside numerous parameters resulting from the complexity of cancer–immune system interactions. It is instructive to use mathematical models to tackle this problem. Methods: In this work, we adapted a model primarily to describe the synergistic effect between single-fraction radiotherapy and immunotherapy (1-methyl tryptophan) observed in previous experiments with glioblastoma-carrying rats. We also showed how the model can be used to generate hypotheses on the outcome of other treatment fractionation schemes. Results: The model successfully reproduced the results of the experiments. Moreover, it provided support for the hypothesis that, for a given biologically effective dose, the efficacy of the combination therapy and the synergy between the two therapies are favoured by the administration of radiotherapy in a hypofractionated regime. Furthermore, for a double-fraction irradiation regimen, the synergy is favoured by a short time interval between the treatment fractions. Conclusion: It was concluded that the model could be fitted to reproduce the experimental data well within its uncertainties. It was also demonstrated that the fitted model can be used to form hypotheses to be validated by further pre-clinical experiments. Advances in knowledge: The results of this work support the hypothesis that the synergetic action of combined radiotherapy and immunotherapy is favoured by using a hypofractionated radiation treatment regimen, given over a short time interval.
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Affiliation(s)
- Arthur Chakwizira
- 1 Medical Radiation Physics, Department of Clinical Sciences Lund, Lund University , Lund , Sweden
| | - Jonatan Ahlstedt
- 2 Rausing Laboratory, Division of Neurosurgery, Department of Clinical Sciences Lund, Lund University , Lund , Sweden
| | - Henrietta Nittby Redebrandt
- 2 Rausing Laboratory, Division of Neurosurgery, Department of Clinical Sciences Lund, Lund University , Lund , Sweden
| | - Crister Ceberg
- 1 Medical Radiation Physics, Department of Clinical Sciences Lund, Lund University , Lund , Sweden
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Abstract
It is well known that nonirradiated cells can exhibit radiation damage (bystander effect), and recent findings have shown that nonirradiated cells may help protect irradiated cells (rescue effect). These findings call into question the traditional view of radiation response: cells cannot be envisioned as isolated units. Here, we investigated traditional colony formation assays to determine if they also comprise cellular communication affecting the radiation response, using colony formation assays with varying numbers of cells, modulated beam irradiation and media transfer. Our findings showed that surviving fraction gradually increased with increasing number of irradiated cells. Specifically, for DU-145 human prostate cancer cells, surviving fraction increased 1.9-to-4.1-fold after 5-12 Gy irradiation; and for MM576 human melanoma cells, surviving fraction increased 1.9-fold after 5 Gy irradiation. Furthermore, increased surviving fraction was evident after modulated beam irradiation, where irradiated cells could communicate with nonirradiated cells. Media from dense cell culture also increased surviving fraction. The results suggest that traditional colony formation assays comprise unavoidable cellular communication affecting radiation outcome and the shape of the survival curve. We also propose that the increased in-field surviving fraction after modulated beam irradiation is due to the same effect.
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Affiliation(s)
| | - Crister Ceberg
- b Medical Radiation Physics, Department of Clinical Sciences Lund, Skane University Hospital, Lund University, Lund, Sweden
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Ahlstedt J, Ceberg C, Salford LG, Redebrandt HN. IMMU-27. OPTIMIZING THE COMBINATORY TREATMENT OF LOW-DOSE RADIATION AND INDOLEAMINE-2,3-DEOXYGENASE INHIBITION FOR GLIOBLASTOMA. Neuro Oncol 2017. [DOI: 10.1093/neuonc/nox168.485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Benedek H, Ahlström M, Nilsson P, Engström P, Knöös T, Ceberg C. The Dosimetric Effect of Prostate Motion in Flattening Filter Free VMAT Treatments Using Extreme Hypofractionation. Int J Radiat Oncol Biol Phys 2017. [DOI: 10.1016/j.ijrobp.2017.06.2141] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Day L, Smyth L, Holm M, Rogers P, Engström P, Ceberg C, Poole C, Crosbie J, Senthi S, Woodford K. EP-1563: Treatment planning for synchrotron microbeam radiotherapy. Radiother Oncol 2017. [DOI: 10.1016/s0167-8140(17)31998-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Ceberg C, Ahlstedt J, Redebrant Nittby H. EP-1599: Mathematical modeling of the synergistic combination of cancer immunotherapy and radiotherapy. Radiother Oncol 2017. [DOI: 10.1016/s0167-8140(17)32034-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Edvardsson A, Nordstrom F, Ceberg C, Ceberg S. Motion-Induced Interplay Effects for Hypofractionated Volumetric Modulated Arc Therapy Treatment of Liver Tumors—Dependence on Breathing Pattern, Dose Rate, and Plan Modulation Complexity. Int J Radiat Oncol Biol Phys 2016. [DOI: 10.1016/j.ijrobp.2016.06.2283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Persson E, Nordström F, Siversson C, Ceberg C. OC-0156: MRI only prostate radiotherapy using synthetic CT images. Radiother Oncol 2016. [DOI: 10.1016/s0167-8140(16)31405-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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46
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Ahlström M, Benedek H, Nilsson P, Knöös T, Ceberg C. PO-0855: Flattening Filter Free VMAT for extreme hypofractionation of prostate cancer. Radiother Oncol 2016. [DOI: 10.1016/s0167-8140(16)32105-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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47
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Edvardsson A, Nordström F, Ceberg C, Ceberg S. OC-0462: Motion induced interplay effects for hypo-fractionated FFF VMAT treatment of liver tumours. Radiother Oncol 2016. [DOI: 10.1016/s0167-8140(16)31711-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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48
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Dalaryd M, Knöös T, Ceberg C. EP-1597: Investigation of in-air output ratios in FFF beams. Radiother Oncol 2016. [DOI: 10.1016/s0167-8140(16)32847-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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49
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Petersson K, Nilsson P, Engström P, Knöös T, Ceberg C. Evaluation of dual-arc VMAT radiotherapy treatment plans automatically generated via dose mimicking. Acta Oncol 2015; 55:523-5. [PMID: 26361238 DOI: 10.3109/0284186x.2015.1080855] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Kristoffer Petersson
- Department of Medical Radiation Physics, Clinical Sciences, Lund, Lund University, Lund, Sweden
| | - Per Nilsson
- Department of Oncology, Skåne University Hospital, Lund University, Lund, Sweden, and
| | - Per Engström
- Department of Medical Radiation Physics, Clinical Sciences, Lund, Lund University, Lund, Sweden
- Radiation Physics, Skåne University Hospital, Lund University, Lund, Sweden
| | - Tommy Knöös
- Department of Medical Radiation Physics, Clinical Sciences, Lund, Lund University, Lund, Sweden
- Radiation Physics, Skåne University Hospital, Lund University, Lund, Sweden
| | - Crister Ceberg
- Department of Medical Radiation Physics, Clinical Sciences, Lund, Lund University, Lund, Sweden
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50
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Petersson K, Nilsson P, Engström P, Knöös T, Ceberg C. Multi-modality optimisation in radiotherapy treatment planning using composite objective values. Acta Oncol 2015; 54:552-6. [PMID: 25178091 DOI: 10.3109/0284186x.2014.953255] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Kristoffer Petersson
- Department of Medical Radiation Physics, Clinical Sciences, Lund, Lund University , Lund , Sweden
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