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Schiavo F, Toma-Dasu I, Kjellsson Lindblom E. Hypoxia dose painting in SBRT - the virtual clinical trial approach. Acta Oncol 2023; 62:1239-1245. [PMID: 37713263 DOI: 10.1080/0284186x.2023.2258272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Accepted: 09/07/2023] [Indexed: 09/16/2023]
Abstract
BACKGROUND Treating hypoxic tumours remains a challenge in radiotherapy as hypoxia leads to enhanced tumour aggressiveness and resistance to radiation. As escalating the doses is rarely feasible within the healthy tissue constraints, dose-painting strategies have been explored. Consensus about the best of care for hypoxic tumours has however not been reached because, among other reasons, the limits of current functional in-vivo imaging systems in resolving the details and dynamics of oxygen transport in tissue. Computational modelling of the tumour microenvironment enables the design and conduction of virtual clinical trials by providing relationships between biological features and treatment outcomes. This study presents a framework for assessing the therapeutic influence of the individual characteristics of the vasculature and the resulting oxygenation of hypoxic tumours in a virtual clinical trial on dose painting in stereotactic body radiotherapy (SBRT) circumventing the limitations of the imaging systems. MATERIAL AND METHODS The homogeneous doses required to overcome hypoxia in simulated SBRT treatments of 1, 3 or 5 fractions were calculated for tumours with heterogeneous oxygenation derived from virtual vascular networks. The tumour control probability (TCP) was calculated for different scenarios for oxygenation dynamics resulting on cellular reoxygenation. RESULTS A three-fractions SBRT treatment delivering 41.9 Gy (SD 2.8) and 26.5 Gy (SD 0.1) achieved only 21% (SD 12) and 48% (SD 17) control in the hypoxic and normoxic subvolumes, respectively whereas fast reoxygenation improved the control by 30% to 50%. TCP values for the individual tumours with similar characteristics, however, might differ substantially, highlighting the crucial role of the magnitude and time evolution of hypoxia at the microscale. CONCLUSION The results show that local microvascular heterogeneities may affect the predicted outcome in the hypoxic core despite escalated doses, emphasizing the role of theoretical modelling in understanding of and accounting for the dominant factors of the tumour microenvironment.
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Affiliation(s)
- Filippo Schiavo
- Department of Physics, Stockholm University, Stockholm, Sweden
- Department of Oncology and Pathology, Karolinska Institutet, Stockholm, Sweden
| | - Iuliana Toma-Dasu
- Department of Physics, Stockholm University, Stockholm, Sweden
- Department of Oncology and Pathology, Karolinska Institutet, Stockholm, Sweden
| | - Emely Kjellsson Lindblom
- Department of Physics, Stockholm University, Stockholm, Sweden
- Department of Oncology and Pathology, Karolinska Institutet, Stockholm, Sweden
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Taylor E. A simple mathematical model of cyclic hypoxia and its impact on hypofractionated radiotherapy. Med Phys 2023; 50:1893-1904. [PMID: 36594511 DOI: 10.1002/mp.16200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 08/29/2022] [Accepted: 12/16/2022] [Indexed: 01/04/2023] Open
Abstract
PURPOSE There is evidence that the population of cells that experience fluctuating oxygen levels ("acute," or, "cyclic" hypoxia) are more radioresistant than chronically hypoxic ones and hence, this population may determine radiotherapy (RT) response, in particular for hypofractionated RT, where reoxygenation may not be as prominent. A considerable effort has been devoted to examining the impact of hypoxia on hypofractionated RT; however, much less attention has been paid to cyclic hypoxia specifically and the role its kinetics may play in determining the efficacy of these treatments. Here, a simple mathematical model of cyclic hypoxia and fractionation effects was worked out to quantify this. METHODS Cancer clonogen survival fraction was estimated using the linear quadratic model, modified to account for oxygen enhancement effects. An analytic approximation for oxygen transport away from a random network of capillaries with fluctuating oxygen levels was used to model inter-fraction tissue oxygen kinetics. The resulting survival fraction formula was used to derive an expression for the iso-survival biologically effective dose (BED), BEDiso-SF . These were computed for some common extra-cranial hypofractionated RT regimens. RESULTS Using relevant literature parameter values, inter-fraction fluctuations in oxygenation were found to result in an added 1-2 logs of clonogen survival fraction in going from five fractions to one for the same nominal BED (i.e., excluding the effects of oxygen levels on radiosensitivity). BEDiso-SF 's for most ultra-hypofractionated (five or fewer fractions) regimens in a given tumor site are similar in magnitude, suggesting iso-efficacy for common fractionation schedules. CONCLUSIONS Although significant, the loss of cell-killing with increasing hypofractionation is not nearly as large as previous estimates based on the assumption of complete reoxygenation between fractions. Most ultra-hypofractionated regimens currently in place offer sufficiently high doses to counter this loss of cell killing, although care should be taken in implementing single-fraction regimens.
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Affiliation(s)
- Edward Taylor
- Princess Margaret Cancer Centre, University Health Network, Toronto, Canada
- Department of Radiation Oncology, University of Toronto, Toronto, Canada
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3
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Towards the virtual tumor for optimizing radiotherapy treatments of hypoxic tumors: a novel model of heterogeneous tissue vasculature and oxygenation. J Theor Biol 2022; 547:111175. [DOI: 10.1016/j.jtbi.2022.111175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 05/14/2022] [Accepted: 05/24/2022] [Indexed: 11/23/2022]
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Gutiérrez E, Sánchez I, Díaz O, Valles A, Balderrama R, Fuentes J, Lara B, Olimón C, Ruiz V, Rodríguez J, Bayardo LH, Chan M, Villafuerte CJ, Padayachee J, Sun A. Current Evidence for Stereotactic Body Radiotherapy in Lung Metastases. ACTA ACUST UNITED AC 2021; 28:2560-2578. [PMID: 34287274 PMCID: PMC8293144 DOI: 10.3390/curroncol28040233] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 07/05/2021] [Accepted: 07/06/2021] [Indexed: 12/25/2022]
Abstract
Lung metastases are the second most common malignant neoplasms of the lung. It is estimated that 20–54% of cancer patients have lung metastases at some point during their disease course, and at least 50% of cancer-related deaths occur at this stage. Lung metastases are widely accepted to be oligometastatic when five lesions or less occur separately in up to three organs. Stereotactic body radiation therapy (SBRT) is a noninvasive, safe, and effective treatment for metastatic lung disease in carefully selected patients. There is no current consensus on the ideal dose and fractionation for SBRT in lung metastases, and it is the subject of study in ongoing clinical trials, which examines different locations in the lung (central and peripheral). This review discusses current indications, fractionations, challenges, and technical requirements for lung SBRT.
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Affiliation(s)
- Enrique Gutiérrez
- Princess Margaret Cancer Centre, Radiation Medicine Program, University Health Network, Toronto, ON M5G2M9, Canada; (E.G.); (M.C.); (C.J.V.); (J.P.)
- Department of Radiation Oncology, University of Toronto, Toronto, ON M5G2M9, Canada
| | - Irving Sánchez
- Western National Medical Center, Department of Radiation Oncology, Mexican Institute of Social Security (IMSS), Belisario Domínguez 1000, Guadalajara 44340, Jalisco, Mexico; (I.S.); (O.D.); (A.V.); (R.B.); (J.F.); (B.L.); (C.O.); (V.R.); (J.R.); (L.H.B.)
| | - Omar Díaz
- Western National Medical Center, Department of Radiation Oncology, Mexican Institute of Social Security (IMSS), Belisario Domínguez 1000, Guadalajara 44340, Jalisco, Mexico; (I.S.); (O.D.); (A.V.); (R.B.); (J.F.); (B.L.); (C.O.); (V.R.); (J.R.); (L.H.B.)
| | - Adrián Valles
- Western National Medical Center, Department of Radiation Oncology, Mexican Institute of Social Security (IMSS), Belisario Domínguez 1000, Guadalajara 44340, Jalisco, Mexico; (I.S.); (O.D.); (A.V.); (R.B.); (J.F.); (B.L.); (C.O.); (V.R.); (J.R.); (L.H.B.)
| | - Ricardo Balderrama
- Western National Medical Center, Department of Radiation Oncology, Mexican Institute of Social Security (IMSS), Belisario Domínguez 1000, Guadalajara 44340, Jalisco, Mexico; (I.S.); (O.D.); (A.V.); (R.B.); (J.F.); (B.L.); (C.O.); (V.R.); (J.R.); (L.H.B.)
| | - Jesús Fuentes
- Western National Medical Center, Department of Radiation Oncology, Mexican Institute of Social Security (IMSS), Belisario Domínguez 1000, Guadalajara 44340, Jalisco, Mexico; (I.S.); (O.D.); (A.V.); (R.B.); (J.F.); (B.L.); (C.O.); (V.R.); (J.R.); (L.H.B.)
| | - Brenda Lara
- Western National Medical Center, Department of Radiation Oncology, Mexican Institute of Social Security (IMSS), Belisario Domínguez 1000, Guadalajara 44340, Jalisco, Mexico; (I.S.); (O.D.); (A.V.); (R.B.); (J.F.); (B.L.); (C.O.); (V.R.); (J.R.); (L.H.B.)
| | - Cipatli Olimón
- Western National Medical Center, Department of Radiation Oncology, Mexican Institute of Social Security (IMSS), Belisario Domínguez 1000, Guadalajara 44340, Jalisco, Mexico; (I.S.); (O.D.); (A.V.); (R.B.); (J.F.); (B.L.); (C.O.); (V.R.); (J.R.); (L.H.B.)
| | - Víctor Ruiz
- Western National Medical Center, Department of Radiation Oncology, Mexican Institute of Social Security (IMSS), Belisario Domínguez 1000, Guadalajara 44340, Jalisco, Mexico; (I.S.); (O.D.); (A.V.); (R.B.); (J.F.); (B.L.); (C.O.); (V.R.); (J.R.); (L.H.B.)
| | - José Rodríguez
- Western National Medical Center, Department of Radiation Oncology, Mexican Institute of Social Security (IMSS), Belisario Domínguez 1000, Guadalajara 44340, Jalisco, Mexico; (I.S.); (O.D.); (A.V.); (R.B.); (J.F.); (B.L.); (C.O.); (V.R.); (J.R.); (L.H.B.)
| | - Luis H. Bayardo
- Western National Medical Center, Department of Radiation Oncology, Mexican Institute of Social Security (IMSS), Belisario Domínguez 1000, Guadalajara 44340, Jalisco, Mexico; (I.S.); (O.D.); (A.V.); (R.B.); (J.F.); (B.L.); (C.O.); (V.R.); (J.R.); (L.H.B.)
| | - Matthew Chan
- Princess Margaret Cancer Centre, Radiation Medicine Program, University Health Network, Toronto, ON M5G2M9, Canada; (E.G.); (M.C.); (C.J.V.); (J.P.)
- Department of Radiation Oncology, University of Toronto, Toronto, ON M5G2M9, Canada
| | - Conrad J. Villafuerte
- Princess Margaret Cancer Centre, Radiation Medicine Program, University Health Network, Toronto, ON M5G2M9, Canada; (E.G.); (M.C.); (C.J.V.); (J.P.)
- Department of Radiation Oncology, University of Toronto, Toronto, ON M5G2M9, Canada
| | - Jerusha Padayachee
- Princess Margaret Cancer Centre, Radiation Medicine Program, University Health Network, Toronto, ON M5G2M9, Canada; (E.G.); (M.C.); (C.J.V.); (J.P.)
- Department of Radiation Oncology, University of Toronto, Toronto, ON M5G2M9, Canada
| | - Alexander Sun
- Princess Margaret Cancer Centre, Radiation Medicine Program, University Health Network, Toronto, ON M5G2M9, Canada; (E.G.); (M.C.); (C.J.V.); (J.P.)
- Department of Radiation Oncology, University of Toronto, Toronto, ON M5G2M9, Canada
- Correspondence: ; Tel.: +1-41-6946-2853
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Petrović IM, Ristić Fira AM, Keta OD, Petković VD, Petringa G, Cirrone P, Cuttone G. A radiobiological study of carbon ions of different linear energy transfer in resistant human malignant cell lines. Int J Radiat Biol 2020; 96:1400-1412. [DOI: 10.1080/09553002.2020.1820609] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Ivan M. Petrović
- Vinča Institute of Nuclear Sciences, University of Belgrade, Belgrade, Serbia
| | | | - Otilija D. Keta
- Vinča Institute of Nuclear Sciences, University of Belgrade, Belgrade, Serbia
| | - Vladana D. Petković
- Vinča Institute of Nuclear Sciences, University of Belgrade, Belgrade, Serbia
| | - Giada Petringa
- Istituto Nazionale di Fisica Nucleare, LNS, Catania, Italy
| | - Pablo Cirrone
- Istituto Nazionale di Fisica Nucleare, LNS, Catania, Italy
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6
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Effets biologiques des hautes doses par fraction. Cancer Radiother 2020; 24:153-158. [DOI: 10.1016/j.canrad.2019.06.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 06/18/2019] [Accepted: 06/19/2019] [Indexed: 01/29/2023]
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7
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Forster JC, Marcu LG, Bezak E. Approaches to combat hypoxia in cancer therapy and the potential for in silico models in their evaluation. Phys Med 2019; 64:145-156. [PMID: 31515013 DOI: 10.1016/j.ejmp.2019.07.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 06/17/2019] [Accepted: 07/09/2019] [Indexed: 02/07/2023] Open
Abstract
AIM The negative impact of tumour hypoxia on cancer treatment outcome has been long-known, yet there has been little success combating it. This paper investigates the potential role of in silico modelling to help test emerging hypoxia-targeting treatments in cancer therapy. METHODS A Medline search was undertaken on the current landscape of in silico models that simulate cancer therapy and evaluate their ability to test hypoxia-targeting treatments. Techniques and treatments to combat tumour hypoxia and their current challenges are also presented. RESULTS Hypoxia-targeting treatments include tumour reoxygenation, hypoxic cell radiosensitization with nitroimidazoles, hypoxia-activated prodrugs and molecular targeting. Their main challenges are toxicity and not achieving adequate delivery to hypoxic regions of the tumour. There is promising research toward combining two or more of these techniques. Different types of in silico therapy models have been developed ranging from temporal to spatial and from stochastic to deterministic models. Numerous models have compared the effectiveness of different radiotherapy fractionation schedules for controlling hypoxic tumours. Similarly, models could help identify and optimize new treatments for overcoming hypoxia that utilize novel hypoxia-targeting technology. CONCLUSION Current therapy models should attempt to incorporate more sophisticated modelling of tumour angiogenesis/vasculature and vessel perfusion in order to become more useful for testing hypoxia-targeting treatments, which typically rely upon the tumour vasculature for delivery of additional oxygen, (pro)drugs and nanoparticles.
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Affiliation(s)
- Jake C Forster
- SA Medical Imaging, Department of Nuclear Medicine, The Queen Elizabeth Hospital, Woodville South, SA 5011, Australia; Department of Physics, University of Adelaide, North Terrace, Adelaide SA 5005, Australia
| | - Loredana G Marcu
- Faculty of Science, University of Oradea, Oradea 410087, Romania; Cancer Research Institute and School of Health Sciences, University of South Australia, Adelaide SA 5001, Australia.
| | - Eva Bezak
- Department of Physics, University of Adelaide, North Terrace, Adelaide SA 5005, Australia; Cancer Research Institute and School of Health Sciences, University of South Australia, Adelaide SA 5001, Australia
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Cerviño LI, Soultan D, Advani SJ, Cornell M, Yock A, Pettersson N, Song WY, Aguilera J, Murphy J, Hoh C, James C, Paravati A, Coope R, Gill B, Moiseenko V. An in vitro study for the dosimetric and radiobiological validation of respiratory gating in conventional and hypofractionated radiotherapy of the lung: effect of dose, dose rate, and breathing pattern. Phys Med Biol 2019; 64:135009. [PMID: 31189137 DOI: 10.1088/1361-6560/ab2940] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Stereotactic body radiotherapy (SBRT) of the lung has become a standard of care for early-stage inoperable non-small cell lung cancer (NSCLC). A common strategy to manage respiratory motion is gating, which inevitably results in an increase in treatment time, especially in irregularly-breathing patients. Flattening-filter free (FFF) beams allow for delivery of the treatment at a higher dose rate, therefore counteracting the lengthened treatment time due to frequent interruption of the beam during gated radiotherapy. In this study, we perform our in vitro evaluation of the dosimetric and radiobiological effect of gated lung SBRT with simultaneous integrated boost (SIB) using both flattened and FFF beams. A moving thorax-shaped phantom with inserts and applicators was used for simulation, planning, gated treatment delivery measurements and in vitro tests. The effects of gating window, dose rate, and breathing pattern were evaluated. Planned doses represented a typical conventional fractionation, 200 cGy per fraction with SIB to 240 cGy, flattened beam only, and SBRT, 800 cGy with SIB to 900 cGy, flattened and FFF beams. Ideal, as well as regular and irregular patient-specific breathing patterns with and without gating were used. A survival assay for lung adenocarcinoma A549 cell line was performed. Delivered dose was within 6% for locations planned to receive 200 and 800 cGy and within 4% for SIB locations. Time between first beam-on and last beam-off varied from approximately 1.5 min for conventional fractionation, 200/240 cGy, to 10.5 min for gated SBRT, 800/900 cGy doses, flattened beam and irregular breathing motion pattern. With FFF beams dose delivery time was shorter by a factor of 2-3, depending on the gating window and breathing pattern. We have found that, for the most part, survival depended on dose and not on dose rate, gating window, or breathing regularity.
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Affiliation(s)
- Laura I Cerviño
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, CA 92093, United States of America. Author to whom correspondence should be addressed
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9
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Kjellsson Lindblom E, Ureba A, Dasu A, Wersäll P, Even AJG, van Elmpt W, Lambin P, Toma-Dasu I. Impact of SBRT fractionation in hypoxia dose painting - Accounting for heterogeneous and dynamic tumor oxygenation. Med Phys 2019; 46:2512-2521. [PMID: 30924937 DOI: 10.1002/mp.13514] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 02/18/2019] [Accepted: 03/13/2019] [Indexed: 12/11/2022] Open
Abstract
PURPOSE Tumor hypoxia, often found in nonsmall cell lung cancer (NSCLC), implies an increased resistance to radiotherapy. Pretreatment assessment of tumor oxygenation is, therefore, warranted in these patients, as functional imaging of hypoxia could be used as a basis for dose painting. This study aimed at investigating the feasibility of using a method for calculating the dose required in hypoxic subvolumes segmented on 18 F-HX4 positron emission tomography (PET) imaging of NSCLC. METHODS Positron emission tomography imaging data based on the hypoxia tracer 18 F-HX4 of 19 NSCLC patients were included in the study. Normalized tracer uptake was converted to oxygen partial pressure (pO2 ) and hypoxic target volumes (HTVs) were segmented using a threshold of 10 mmHg. Uniform doses required to overcome the hypoxic resistance in the target volumes were calculated based on a previously proposed method taking into account the effect of interfraction reoxygenation, for fractionation schedules ranging from extremely hypofractionated stereotactic body radiotherapy (SBRT) to conventionally fractionated radiotherapy. RESULTS Gross target volumes ranged between 6.2 and 859.6 cm3 , and the hypoxic fraction < 10 mmHg between 1.2% and 72.4%. The calculated doses for overcoming the resistance of cells in the HTVs were comparable to those currently prescribed in clinical practice as well as those previously tested in feasibility studies on dose escalation in NSCLC. Depending on the size of the HTV and the distribution of pO2 , HTV doses were calculated as 43.6-48.4 Gy for a three-fraction schedule, 51.7-57.6 Gy for five fractions, and 59.5-66.4 Gy for eight fractions. For patients in whom the HTV pO2 distribution was more favorable, a lower dose was required despite a bigger volume. Tumor control probability was lower for single-fraction schedules, while higher levels of tumor control probability were found for schedules employing several fractions. CONCLUSIONS The method to account for heterogeneous and dynamic hypoxia in target volume segmentation and dose prescription based on 18 F-HX4-PET imaging appears feasible in NSCLC patients. The distribution of oxygen partial pressure within HTV could impact the required prescribed dose more than the size of the volume.
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Affiliation(s)
- Emely Kjellsson Lindblom
- Medical Radiation Physics, Department of Physics, Stockholm University, Stockholm, S-17176, Sweden
| | - Ana Ureba
- Medical Radiation Physics, Department of Physics, Stockholm University, Stockholm, S-17176, Sweden
| | | | - Peter Wersäll
- Department of Oncology, Karolinska University Hospital, Stockholm, S-17176, Sweden
| | - Aniek J G Even
- Department of Radiation Oncology (MAASTRO), GROW-School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht, 6229, The Netherlands
| | - Wouter van Elmpt
- Department of Radiation Oncology (MAASTRO), GROW-School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht, 6229, The Netherlands
| | - Philippe Lambin
- Department of Radiation Oncology (MAASTRO), GROW-School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht, 6229, The Netherlands
| | - Iuliana Toma-Dasu
- Medical Radiation Physics, Department of Physics, Stockholm University, Stockholm, S-17176, Sweden.,Medical Radiation Physics, Department of Oncology and Pathology, Karolinska Institutet, Stockholm, S-17176, Sweden
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Arnold KM, Flynn NJ, Raben A, Romak L, Yu Y, Dicker AP, Mourtada F, Sims-Mourtada J. The Impact of Radiation on the Tumor Microenvironment: Effect of Dose and Fractionation Schedules. CANCER GROWTH AND METASTASIS 2018; 11:1179064418761639. [PMID: 29551910 PMCID: PMC5846913 DOI: 10.1177/1179064418761639] [Citation(s) in RCA: 98] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 10/23/2017] [Indexed: 02/06/2023]
Abstract
In addition to inducing lethal DNA damage in tumor and stromal cells, radiation can alter the interactions of tumor cells with their microenvironment. Recent technological advances in planning and delivery of external beam radiotherapy have allowed delivery of larger doses per fraction (hypofractionation) while minimizing dose to normal tissues with higher precision. The effects of radiation on the tumor microenvironment vary with dose and fractionation schedule. In this review, we summarize the effects of conventional and hypofractionated radiation regimens on the immune system and tumor stroma. We discuss how these interactions may provide therapeutic benefit in combination with targeted therapies. Understanding the differential effects of radiation dose and fractionation can have implications for choice of combination therapies.
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Affiliation(s)
- Kimberly M Arnold
- Center for Translational Cancer Research, Helen F. Graham Cancer Center & Research Institute, Christiana Care Health System, Newark, DE, USA.,Department of Medical Laboratory Sciences, University of Delaware, Newark, DE, USA
| | - Nicole J Flynn
- Center for Translational Cancer Research, Helen F. Graham Cancer Center & Research Institute, Christiana Care Health System, Newark, DE, USA.,Department of Biological Sciences, University of Delaware, Newark, DE, USA
| | - Adam Raben
- Department of Radiation Oncology, Helen F. Graham Cancer Center & Research Institute, Christiana Care Health System, Newark, DE, USA
| | - Lindsay Romak
- Department of Radiation Oncology, Helen F. Graham Cancer Center & Research Institute, Christiana Care Health System, Newark, DE, USA
| | - Yan Yu
- Department of Radiation Oncology, Sidney Kimmel Medical College & Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA
| | - Adam P Dicker
- Department of Radiation Oncology, Sidney Kimmel Medical College & Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA
| | - Firas Mourtada
- Department of Radiation Oncology, Helen F. Graham Cancer Center & Research Institute, Christiana Care Health System, Newark, DE, USA.,Department of Radiation Oncology, Sidney Kimmel Medical College & Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA
| | - Jennifer Sims-Mourtada
- Center for Translational Cancer Research, Helen F. Graham Cancer Center & Research Institute, Christiana Care Health System, Newark, DE, USA.,Department of Medical Laboratory Sciences, University of Delaware, Newark, DE, USA.,Department of Biological Sciences, University of Delaware, Newark, DE, USA
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11
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D'Andrea M, Strolin S, Ungania S, Cacciatore A, Bruzzaniti V, Marconi R, Benassi M, Strigari L. Radiobiological Optimization in Lung Stereotactic Body Radiation Therapy: Are We Ready to Apply Radiobiological Models? Front Oncol 2018; 7:321. [PMID: 29359121 PMCID: PMC5766682 DOI: 10.3389/fonc.2017.00321] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Accepted: 12/11/2017] [Indexed: 12/25/2022] Open
Abstract
Lung tumors are often associated with a poor prognosis although different schedules and treatment modalities have been extensively tested in the clinical practice. The complexity of this disease and the use of combined therapeutic approaches have been investigated and the use of high dose-rates is emerging as effective strategy. Technological improvements of clinical linear accelerators allow combining high dose-rate and a more conformal dose delivery with accurate imaging modalities pre- and during therapy. This paper aims at reporting the state of the art and future direction in the use of radiobiological models and radiobiological-based optimizations in the clinical practice for the treatment of lung cancer. To address this issue, a search was carried out on PubMed database to identify potential papers reporting tumor control probability and normal tissue complication probability for lung tumors. Full articles were retrieved when the abstract was considered relevant, and only papers published in English language were considered. The bibliographies of retrieved papers were also searched and relevant articles included. At the state of the art, dose–response relationships have been reported in literature for local tumor control and survival in stage III non-small cell lung cancer. Due to the lack of published radiobiological models for SBRT, several authors used dose constraints and models derived for conventional fractionation schemes. Recently, several radiobiological models and parameters for SBRT have been published and could be used in prospective trials although external validations are recommended to improve the robustness of model predictive capability. Moreover, radiobiological-based functions have been used within treatment planning systems for plan optimization but the advantages of using this strategy in the clinical practice are still under discussion. Future research should be directed toward combined regimens, in order to potentially improve both local tumor control and survival. Indeed, accurate knowledge of the relevant parameters describing tumor biology and normal tissue response is mandatory to correctly address this issue. In this context, the role of medical physicists and the AAPM in the development of radiobiological models is crucial for the progress of developing specific tool for radiobiological-based optimization treatment planning.
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Affiliation(s)
- Marco D'Andrea
- Laboratory of Medical Physics and Expert Systems, Regina Elena National Cancer Institute, Rome, Italy
| | - Silvia Strolin
- Laboratory of Medical Physics and Expert Systems, Regina Elena National Cancer Institute, Rome, Italy
| | - Sara Ungania
- Laboratory of Medical Physics and Expert Systems, Regina Elena National Cancer Institute, Rome, Italy
| | - Alessandra Cacciatore
- Laboratory of Medical Physics and Expert Systems, Regina Elena National Cancer Institute, Rome, Italy
| | - Vicente Bruzzaniti
- Laboratory of Medical Physics and Expert Systems, Regina Elena National Cancer Institute, Rome, Italy
| | - Raffaella Marconi
- Laboratory of Medical Physics and Expert Systems, Regina Elena National Cancer Institute, Rome, Italy
| | - Marcello Benassi
- Laboratory of Medical Physics and Expert Systems, Regina Elena National Cancer Institute, Rome, Italy
| | - Lidia Strigari
- Laboratory of Medical Physics and Expert Systems, Regina Elena National Cancer Institute, Rome, Italy
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12
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Bell JP, Patel P, Higgins K, McDonald MW, Roper J. Fine-tuning the normal tissue objective in eclipse for lung stereotactic body radiation therapy. Med Dosim 2017; 43:344-350. [PMID: 29277249 DOI: 10.1016/j.meddos.2017.11.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 11/13/2017] [Accepted: 11/13/2017] [Indexed: 12/31/2022]
Abstract
The purpose of this study was to characterize the effects of the normal tissue objective (NTO) on lung stereotactic body radiation therapy (SBRT) dose distributions. The NTO is a spatially varying constraint used in Eclipse to limit dose to normal tissues by steepening the dose gradient. However, the multitude of potential NTO setting combinations challenges optimal NTO tuning. In the present study, a broad range of NTO settings are investigated for lung SBRT treatment planning with volumetric modulated arc therapy(VMAT). Ten prior lung SBRT cases were replanned using NTO priorities of 1, 50, 100, 200, 500, and 999 in combination with fall-off values of 0.01, 0.05, 0.10, 0.15, 0.20, 0.30, 0.50, 1.00, and 5.00 mm-1 and the automatic NTO. NTO distances to planning target volume (PTV), start dose, and end dose were 1 mm, 100%, and 10%, respectively, for all 600 plans. Prescription dose covered 95% of the PTV. The following metrics were recorded: conformity index (CI), ratio of the 50% prescription isodose volume to PTV (R50%), maximum dose 2 cm away from PTV (D2cm), lung volume of ≥20 Gy (V20Gy), maximum PTV dose (PTVmax), and monitor units (MUs). Differences between prior plans and NTO plans were evaluated using the Wilcoxon signed-rank test. Different combinations of NTO settings resulted in wide-ranging plan quality metrics: CI (1.00 to 1.54), R50% (3.95 to 7.57), D2cm (33.4% to 67.9%), V20Gy (1.66% to 2.75%), MU (1.81 cGy-1 to 4.69 cGy-1), and PTVmax (118% to 175%). Although no settings were optimal for all metrics, a fall-off of 0.15 mm-1 and a priority of 500 best satisfied institutional criteria. Compared with prior plans, NTO plans resulted in significantly lower R50% (4.00 vs 4.35, p = 0.002), lower V20Gy (1.22% vs 1.32%, p = 0.006), and higher PTVmax (138% vs 122%, p = 0.002). All of the prior and well-tuned NTO plans met Radiation Therapy Oncology Group (RTOG) 0813 guidelines. Lung SBRT dose distributions were characterized across a range of NTO settings. NTO plans with well-tuned settings compared favorably with prior plans.
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Affiliation(s)
- James P Bell
- Department of Radiation Oncology, Simmons Comprehensive Cancer Center at the University of Texas Southwestern Medical Center, Dallas, TX
| | - Pretesh Patel
- Winship Cancer Institute of Emory University, 1356 Clifton Road NE, Building C, Atlanta, Georgia 30322
| | - Kristin Higgins
- Winship Cancer Institute of Emory University, 1356 Clifton Road NE, Building C, Atlanta, Georgia 30322
| | - Mark W McDonald
- Hospital Corporation of America, Sarah Cannon Cancer Center, Department of Radiation Oncology, 2410 Patterson Street, Basement Level, Nashville, TN 37203
| | - Justin Roper
- Hospital Corporation of America, Sarah Cannon Cancer Center, Department of Radiation Oncology, 2410 Patterson Street, Basement Level, Nashville, TN 37203.
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Ruggieri R, Stavrev P, Naccarato S, Stavreva N, Alongi F, Nahum AE. Optimal dose and fraction number in SBRT of lung tumours: A radiobiological analysis. Phys Med 2017; 44:188-195. [DOI: 10.1016/j.ejmp.2016.12.012] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 12/02/2016] [Accepted: 12/14/2016] [Indexed: 12/25/2022] Open
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14
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Klement RJ. Fasting, Fats, and Physics: Combining Ketogenic and Radiation Therapy against Cancer. Complement Med Res 2017; 25:102-113. [DOI: 10.1159/000484045] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Radiotherapy (RT) is a mainstay in the treatment of solid tumors and works by physicochemical reactions inducing oxidative stress in cells. Because in practice the efficacy of RT is limited by its toxicity to normal tissues, any strategy that selectively increases the radiosensitivity of tumor cells or boosts the radioresistance of normal cells is a valuable adjunct to RT. In this review, I summarize preclinical and clinical data supporting the hypothesis that ketogenic therapy through fasting and/or ketogenic diets can be utilized as such an adjunct in order to improve the outcome after RT, in terms of both higher tumor control and lower normal-tissue complication probability. The first effect relates to the metabolic shift from glycolysis towards mitochondrial metabolism, which selectively increases reactive oxygen species (ROS) production and impairs adenoside triphosphate (ATP) production in tumor cells. The second effect is based on the differential stress resistance phenomenon describing the reprogramming of normal cells, but not tumor cells, from proliferation towards maintenance and stress resistance when glucose and growth factor levels are decreased and ketone body levels are elevated. Underlying both effects are metabolic differences between normal and tumor cells. Ketogenic therapy is a non-toxic and cost-effective complementary treatment option that exploits these differences and deserves further clinical investigation.
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15
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Abstract
PURPOSE Radiotherapy (RT) is a mainstay in the treatment of solid tumors and works by inducing free radical stress in tumor cells, leading to loss of reproductive integrity. The optimal treatment strategy has to consider damage to both tumor and normal cells and is determined by five factors known as the 5 R's of radiobiology: Reoxygenation, DNA repair, radiosensitivity, redistribution in the cell cycle and repopulation. The aim of this review is (i) to present evidence that these 5 R's are strongly influenced by cellular and whole-body metabolism that in turn can be modified through ketogenic therapy in form of ketogenic diets and short-term fasting and (ii) to stimulate new research into this field including some research questions deserving further study. CONCLUSIONS Preclinical and some preliminary clinical data support the hypothesis that ketogenic therapy could be utilized as a complementary treatment in order to improve the outcome after RT, both in terms of higher tumor control and in terms of lower normal tissue complication probability. The first effect relates to the metabolic shift from glycolysis toward mitochondrial metabolism that selectively increases ROS production and impairs ATP production in tumor cells. The second effect is based on the differential stress resistance phenomenon, which is achieved when glucose and growth factors are reduced and ketone bodies are elevated, reprogramming normal but not tumor cells from proliferation toward maintenance and stress resistance. Underlying both effects are metabolic differences between normal and tumor cells that ketogenic therapy seeks to exploit. Specifically, the recently discovered role of the ketone body β-hydroxybutyrate as an endogenous class-I histone deacetylase inhibitor suggests a dual role as a radioprotector of normal cells and a radiosensitzer of tumor cells that opens up exciting possibilities to employ ketogenic therapy as a cost-effective adjunct to radiotherapy against cancer.
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Affiliation(s)
- Rainer J Klement
- a Department of Radiotherapy and Radiation Oncology , Leopoldina Hospital , Schweinfurt , Germany
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Siva S, Slotman BJ. Stereotactic Ablative Body Radiotherapy for Lung Metastases: Where is the Evidence and What are We Doing With It? Semin Radiat Oncol 2017; 27:229-239. [PMID: 28577830 DOI: 10.1016/j.semradonc.2017.03.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
This review provides an overview of the use of stereotactic ablative body radiotherapy (SABR) for pulmonary metastases. The local control rates after SABR are generally >90%. Whether this also translates into a significant improvement in overall survival is the subject of ongoing studies. New exciting opportunities including the integration of SABR with targeted and immune therapies as well as some competing treatment strategies are discussed.
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Affiliation(s)
- Shankar Siva
- Department of Radiation Oncology, Peter MacCallum Cancer Centre, East Melbourne, Australia
| | - Ben J Slotman
- Department of Radiation Oncology, VU University Medical Center, Amsterdam, The Netherlands.
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Stochastic Predictions of Cell Kill During Stereotactic Ablative Radiation Therapy: Do Hypoxia and Reoxygenation Really Matter? Int J Radiat Oncol Biol Phys 2016; 95:1290-7. [DOI: 10.1016/j.ijrobp.2016.03.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Revised: 02/26/2016] [Accepted: 03/11/2016] [Indexed: 11/24/2022]
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18
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Huang BT, Lin Z, Lin PX, Lu JY, Chen CZ. Radiobiological modeling of two stereotactic body radiotherapy schedules in patients with stage I peripheral non-small cell lung cancer. Oncotarget 2016; 7:40746-40755. [PMID: 27203739 PMCID: PMC5130041 DOI: 10.18632/oncotarget.9442] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Accepted: 04/18/2016] [Indexed: 02/05/2023] Open
Abstract
This study aims to compare the radiobiological response of two stereotactic body radiotherapy (SBRT) schedules for patients with stage I peripheral non-small cell lung cancer (NSCLC) using radiobiological modeling methods. Volumetric modulated arc therapy (VMAT)-based SBRT plans were designed using two dose schedules of 1 × 34 Gy (34 Gy in 1 fraction) and 4 × 12 Gy (48 Gy in 4 fractions) for 19 patients diagnosed with primary stage I NSCLC. Dose to the gross target volume (GTV), planning target volume (PTV), lung and chest wall (CW) were converted to biologically equivalent dose in 2 Gy fraction (EQD2) for comparison. Five different radiobiological models were employed to predict the tumor control probability (TCP) value. Three additional models were utilized to estimate the normal tissue complication probability (NTCP) value for the lung and the modified equivalent uniform dose (mEUD) value to the CW. Our result indicates that the 1 × 34 Gy dose schedule provided a higher EQD2 dose to the tumor, lung and CW. Radiobiological modeling revealed that the TCP value for the tumor, NTCP value for the lung and mEUD value for the CW were 7.4% (in absolute value), 7.2% (in absolute value) and 71.8% (in relative value) higher on average, respectively, using the 1 × 34 Gy dose schedule.
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Affiliation(s)
- Bao-tian Huang
- Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou 515031, China
| | - Zhu Lin
- Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou 515031, China
| | - Pei-xian Lin
- Department of Nosocomial Infection Management, The Second Affiliated Hospital of Shantou University Medical College, Shantou 515041, China
| | - Jia-yang Lu
- Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou 515031, China
| | - Chuang-zhen Chen
- Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou 515031, China
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19
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Huang BT, Lu JY, Lin PX, Chen JZ, Li DR, Chen CZ. Radiobiological modeling analysis of the optimal fraction scheme in patients with peripheral non-small cell lung cancer undergoing stereotactic body radiotherapy. Sci Rep 2015; 5:18010. [PMID: 26657569 PMCID: PMC4676016 DOI: 10.1038/srep18010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 11/10/2015] [Indexed: 02/07/2023] Open
Abstract
This study aimed to determine the optimal fraction scheme (FS) in patients with small peripheral non-small cell lung cancer (NSCLC) undergoing stereotactic body radiotherapy (SBRT) with the 4 × 12 Gy scheme as the reference. CT simulation data for sixteen patients diagnosed with primary NSCLC or metastatic tumor with a single peripheral lesion ≤3 cm were used in this study. Volumetric modulated arc therapy (VMAT) plans were designed based on ten different FS of 1 × 25 Gy, 1 × 30 Gy, 1 × 34 Gy, 3 × 15 Gy, 3 × 18 Gy, 3 × 20 Gy, 4 × 12 Gy, 5 × 12 Gy, 6 × 10 Gy and 10 × 7 Gy. Five different radiobiological models were employed to predict the tumor control probability (TCP) value. Three other models were utilized to estimate the normal tissue complication probability (NTCP) value to the lung and the modified equivalent uniform dose (mEUD) value to the chest wall (CW). The 1 × 30 Gy regimen is recommended to achieve 4.2% higher TCP and slightly higher NTCP and mEUD values to the lung and CW compared with the 4 × 12 Gy schedule, respectively. This regimen also greatly shortens the treatment duration. However, the 3 × 15 Gy schedule is suggested in patients where the lung-to-tumor volume ratio is small or where the tumor is adjacent to the CW.
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Affiliation(s)
- Bao-Tian Huang
- Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, 7 Raoping Road, Shantou 515031, China
| | - Jia-Yang Lu
- Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, 7 Raoping Road, Shantou 515031, China
| | - Pei-Xian Lin
- Department of Nosocomial Infection Management, The Second Affiliated Hospital of Shantou University Medical College, 69 North Dongsha Road, Shantou 515041, China
| | - Jian-Zhou Chen
- Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, 7 Raoping Road, Shantou 515031, China
| | - De-Rui Li
- Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, 7 Raoping Road, Shantou 515031, China
| | - Chuang-Zhen Chen
- Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, 7 Raoping Road, Shantou 515031, China
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20
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Lindblom E, Dasu A, Toma-Dasu I. Optimal fractionation in radiotherapy for non-small cell lung cancer--a modelling approach. Acta Oncol 2015. [PMID: 26217986 DOI: 10.3109/0284186x.2015.1061207] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND Conventionally fractionated radiotherapy (CFRT) has proven ineffective in treating non-small cell lung cancer while more promising results have been obtained with stereotactic body radiotherapy (SBRT). Hypoxic tumours, however, might present a challenge to extremely hypofractionated schedules due to the decreased possibility for inter-fraction fast reoxygenation. A potentially successful compromise might be found in schedules employing several fractions of varying fractional doses. In this modelling study, a wide range of fractionation schedules from single-fraction treatments to heterogeneous, multifraction schedules taking into account repair, repopulation, reoxygenation and radiosensitivity of the tumour cells, has been explored with respect to the probability of controlling lung tumours. MATERIAL AND METHODS The response to radiation of tumours with heterogeneous spatial and temporal oxygenation was simulated including the effects of accelerated repopulation and intra-fraction repair. Various treatments with respect to time, dose and fractionation were considered and the outcome was estimated as Poisson-based tumour control probability for local control. RESULTS For well oxygenated tumours, heterogeneous fractionation could increase local control while hypoxic tumours are not efficiently targeted by such treatments despite reoxygenation. For hypofractionated treatments employing large doses per fraction, a synergistic effect was observed between intra-fraction repair and inter-fraction fast reoxygenation of the hypoxic cells as demonstrated by a reduction in D50 from 53.3 Gy for 2 fractions to 52.7 Gy for 5 fractions. CONCLUSIONS For well oxygenated tumours, heterogeneous fractionation schedules could increase local control rates substantially compared to CFRT. For hypoxic tumours, SBRT-like hypofractionated schedules might be optimal despite the increased risk of intra-fraction repair due to a synergistic effect with inter-fraction reoxygenation.
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Affiliation(s)
- Emely Lindblom
- a Medical Radiation Physics, Department of Physics , Stockholm University , Stockholm , Sweden
| | - Alexandru Dasu
- b Department of Radiation Physics and Department of Medical and Health Sciences , Linköping University , Linköping , Sweden
| | - Iuliana Toma-Dasu
- a Medical Radiation Physics, Department of Physics , Stockholm University , Stockholm , Sweden
- c Medical Radiation Physics, Department of Oncology and Pathology , Karolinska Institutet , Stockholm , Sweden
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High-dose and fractionation effects in stereotactic radiation therapy: Analysis of tumor control data from 2965 patients. Radiother Oncol 2015; 115:327-34. [DOI: 10.1016/j.radonc.2015.05.013] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 04/20/2015] [Accepted: 05/14/2015] [Indexed: 01/08/2023]
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22
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Brustugun OT. Hypoxia as a cause of treatment failure in non-small cell carcinoma of the lung. Semin Radiat Oncol 2014; 25:87-92. [PMID: 25771412 DOI: 10.1016/j.semradonc.2014.11.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Hypoxia is an important factor in tumor biology and is both a predictive and a prognostic factor in non-small cell lung cancer. The negative effect of low oxygenation on radiation therapy effect has been known for decades, but more recent research has emphasized that hypoxia also has a profound effect on a tumor's aggression and metastatic propensity. In this review, current knowledge on both these aspects of treatment failure in NSCLC due to hypoxia has been discussed, along with a presentation of modern methods for hypoxia measurement and current therapeutical interventions to circumvent the negative effect of hypoxia on treatment results.
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Affiliation(s)
- Odd Terje Brustugun
- Department of Oncology, Oslo University Hospital-The Norwegian Radium Hospital, Oslo, Norway; Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
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