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Jia MX, Zhang X, Yin C, Feng G, Li N, Gao S, Liu DW. Peripheral dose measurements in cervical cancer radiotherapy: a comparison of volumetric modulated arc therapy and step-and-shoot IMRT techniques. Radiat Oncol 2014; 9:61. [PMID: 24555547 PMCID: PMC3996072 DOI: 10.1186/1748-717x-9-61] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Accepted: 02/13/2014] [Indexed: 11/10/2022] Open
Abstract
Purpose The aim of this study was to investigate the peripheral doses resulting from volumetric modulated arc therapy (VMAT) and intensity modulated radiotherapy (IMRT) techniques in cervical cancer radiotherapy. Methods Nine patients with cervical cancer had treatment planned with both VMAT and IMRT. A specially designed phantom was used for this study, with ion chambers placed at interest points approximating the position of the breast, thyroid, and lens. The peripheral doses at the phantom interest points were measured and compared between the VMAT and IMRT techniques. Results VMAT provides a potential dosimetric advantage compared with IMRT. The mean (± standard deviation) peripheral dose to the breast point for 1 fraction (2 Gy) during VMAT measured 5.13 ± 0.96 mGy, compared with 9.04 ± 1.50 mGy for IMRT. At the thyroid and lens interest points, the mean (± standard deviation) peripheral dose during VMAT was 2.19 ± 0.33 and 2.16 ± 0.28 mGy, compared with 7.07 ± 0.76 and 6.97 ± 0.91 mGy for IMRT, respectively. VMAT reduced the monitor units used by 28% and shortened the treatment delivery time by 54% compared with IMRT. Conclusion While the dosimetric results are similar for both techniques, VMAT results in a lower peripheral dose to the patient and reduces the monitor-unit usage and treatment delivery time compared with IMRT.
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Affiliation(s)
- Ming X Jia
- Department of Radiation Oncology, Shengjing Hospital of China Medical University, Shenyang 110022, China.
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52
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[The issue of low doses in radiation therapy and impact on radiation-induced secondary malignancies]. Bull Cancer 2014; 100:1333-42. [PMID: 24257106 DOI: 10.1684/bdc.2013.1855] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Several studies have well documented that the risk of secondary neoplasms is increasing among patients having received radiation therapy as part of their primary anticancer treatment. Most frequently, radiation-induced neoplasms occur in volume exposed to high doses. However, the impact of "low" doses (<5 Gy) in radiation-induced carcinogenesis should be clinically considered because modern techniques of intensity-modulated radiation therapy (IMRT) or stereotactic irradiation significantly increase tissue volumes receiving low doses. The risk inherent to these technologies remains uncertain and estimates closely depend on the chosen risk model. According to the (debated) linear no-threshold model, the risk of secondary neoplasms could be twice higher with IMRT, as compared to conformal radiation therapy. It seems that only proton therapy could decrease both high and low doses delivered to non-target volumes. Except for pediatric tumors, for which the unequivocal risk of second malignancies (much higher than in adults) should be taken into account, epidemiological data suggest that the risk of secondary cancer related to low doses could be very low, even negligible in some cases. However, clinical follow-up remains insufficient and a marginal increase in secondary tumors could counterbalance the benefit of a highly sophisticated irradiation technique. It therefore remains necessary to integrate the potential risk of new irradiation modalities in a risk-adapted strategy taking into account therapeutic objectives but also associated risk factors, such as age (essentially), chemotherapy, or life style.
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53
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El-Saghire H, Vandevoorde C, Ost P, Monsieurs P, Michaux A, De Meerleer G, Baatout S, Thierens H. Intensity modulated radiotherapy induces pro-inflammatory and pro-survival responses in prostate cancer patients. Int J Oncol 2014; 44:1073-83. [PMID: 24435511 PMCID: PMC3977809 DOI: 10.3892/ijo.2014.2260] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Accepted: 11/11/2013] [Indexed: 12/21/2022] Open
Abstract
Intensity modulated radiotherapy (IMRT) is one of the modern conformal radiotherapies that is widely used within the context of cancer patient treatment. It uses multiple radiation beams targeted to the tumor, however, large volumes of the body receive low doses of irradiation. Using γ-H2AX and global genome expression analysis, we studied the biological responses induced by low doses of ionizing radiation in prostate cancer patients following IMRT. By means of different bioinformatics analyses, we report that IMRT induced an inflammatory response via the induction of viral, adaptive, and innate immune signaling. In response to growth factors and immune-stimulatory signaling, positive regulation in the progression of cell cycle and DNA replication were induced. This denotes pro-inflammatory and pro-survival responses. Furthermore, double strand DNA breaks were induced in every patient 30 min after the treatment and remaining DNA repair and damage signaling continued after 18-24 h. Nine genes belonging to inflammatory responses (TLR3, SH2D1A and IL18), cell cycle progression (ORC4, SMC2 and CCDC99) and DNA damage and repair (RAD17, SMC6 and MRE11A) were confirmed by quantitative RT-PCR. This study emphasizes that the risk assessment of health effects from the out-of-field low doses during IMRT should be of concern, as these may increase the risk of secondary cancers and/or systemic inflammation.
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Affiliation(s)
- Houssein El-Saghire
- Radiobiology Unit, Molecular and Cellular Biology, Belgian Nuclear Research Centre (SCK·CEN), Mol, Belgium
| | | | - Piet Ost
- Department of Radiation Oncology, Ghent University Hospital, Gent, Belgium
| | - Pieter Monsieurs
- Radiobiology Unit, Molecular and Cellular Biology, Belgian Nuclear Research Centre (SCK·CEN), Mol, Belgium
| | - Arlette Michaux
- Radiobiology Unit, Molecular and Cellular Biology, Belgian Nuclear Research Centre (SCK·CEN), Mol, Belgium
| | - Gert De Meerleer
- Department of Radiation Oncology, Ghent University Hospital, Gent, Belgium
| | - Sarah Baatout
- Radiobiology Unit, Molecular and Cellular Biology, Belgian Nuclear Research Centre (SCK·CEN), Mol, Belgium
| | - Hubert Thierens
- Department of Basic Medical Sciences, Ghent University, Gent, Belgium
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Abo-Madyan Y, Aziz MH, Aly MMOM, Schneider F, Sperk E, Clausen S, Giordano FA, Herskind C, Steil V, Wenz F, Glatting G. Second cancer risk after 3D-CRT, IMRT and VMAT for breast cancer. Radiother Oncol 2014; 110:471-6. [PMID: 24444525 DOI: 10.1016/j.radonc.2013.12.002] [Citation(s) in RCA: 114] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2012] [Revised: 12/02/2013] [Accepted: 12/21/2013] [Indexed: 01/01/2023]
Abstract
PURPOSE Second cancer risk after breast conserving therapy is becoming more important due to improved long term survival rates. In this study, we estimate the risks for developing a solid second cancer after radiotherapy of breast cancer using the concept of organ equivalent dose (OED). MATERIALS AND METHODS Computer-tomography scans of 10 representative breast cancer patients were selected for this study. Three-dimensional conformal radiotherapy (3D-CRT), tangential intensity modulated radiotherapy (t-IMRT), multibeam intensity modulated radiotherapy (m-IMRT), and volumetric modulated arc therapy (VMAT) were planned to deliver a total dose of 50 Gy in 2 Gy fractions. Differential dose volume histograms (dDVHs) were created and the OEDs calculated. Second cancer risks of ipsilateral, contralateral lung and contralateral breast cancer were estimated using linear, linear-exponential and plateau models for second cancer risk. RESULTS Compared to 3D-CRT, cumulative excess absolute risks (EAR) for t-IMRT, m-IMRT and VMAT were increased by 2 ± 15%, 131 ± 85%, 123 ± 66% for the linear-exponential risk model, 9 ± 22%, 82 ± 96%, 71 ± 82% for the linear and 3 ± 14%, 123 ± 78%, 113 ± 61% for the plateau model, respectively. CONCLUSION Second cancer risk after 3D-CRT or t-IMRT is lower than for m-IMRT or VMAT by about 34% for the linear model and 50% for the linear-exponential and plateau models, respectively.
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Affiliation(s)
- Yasser Abo-Madyan
- Department of Radiation Oncology, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Germany; Department of Radiation Oncology and Nuclear Medicine (NEMROCK), Faculty of Medicine, Cairo University, Egypt
| | - Muhammad Hammad Aziz
- Department of Radiation Oncology, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Germany; Department of Physics, COMSATS Institute of Information and Technology, Islamabad, Pakistan
| | - Moamen M O M Aly
- Medical Radiation Physics/Radiation Protection, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Germany; Department of Radiotherapy and Nuclear Medicine, South Egypt Cancer Institute, Assiut University, Egypt
| | - Frank Schneider
- Department of Radiation Oncology, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Germany
| | - Elena Sperk
- Department of Radiation Oncology, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Germany
| | - Sven Clausen
- Department of Radiation Oncology, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Germany; Medical Radiation Physics/Radiation Protection, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Germany
| | - Frank A Giordano
- Department of Radiation Oncology, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Germany
| | - Carsten Herskind
- Department of Radiation Oncology, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Germany
| | - Volker Steil
- Department of Radiation Oncology, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Germany
| | - Frederik Wenz
- Department of Radiation Oncology, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Germany
| | - Gerhard Glatting
- Department of Radiation Oncology, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Germany; Medical Radiation Physics/Radiation Protection, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Germany.
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Asur R, Butterworth KT, Penagaricano JA, Prise KM, Griffin RJ. High dose bystander effects in spatially fractionated radiation therapy. Cancer Lett 2013; 356:52-7. [PMID: 24246848 DOI: 10.1016/j.canlet.2013.10.032] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Revised: 10/24/2013] [Accepted: 10/28/2013] [Indexed: 12/25/2022]
Abstract
Traditional radiotherapy of bulky tumors has certain limitations. Spatially fractionated radiation therapy (GRID) and intensity modulated radiotherapy (IMRT) are examples of advanced modulated beam therapies that help in significant reductions in normal tissue damage. GRID refers to the delivery of a single high dose of radiation to a large treatment area that is divided into several smaller fields, while IMRT allows improved dose conformity to the tumor target compared to conventional three-dimensional conformal radiotherapy. In this review, we consider spatially fractionated radiotherapy approaches focusing on GRID and IMRT, and present complementary evidence from different studies which support the role of radiation induced signaling effects in the overall radiobiological rationale for these treatments.
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Affiliation(s)
- Rajalakshmi Asur
- Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States
| | - Karl T Butterworth
- Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, Northern Ireland, United Kingdom
| | - Jose A Penagaricano
- Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States
| | - Kevin M Prise
- Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, Northern Ireland, United Kingdom
| | - Robert J Griffin
- Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States.
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56
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Murray L, Henry A, Hoskin P, Siebert FA, Venselaar J. Second primary cancers after radiation for prostate cancer: a review of data from planning studies. Radiat Oncol 2013; 8:172. [PMID: 23835163 PMCID: PMC3724744 DOI: 10.1186/1748-717x-8-172] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Accepted: 06/23/2013] [Indexed: 11/29/2022] Open
Abstract
A review of planning studies was undertaken to evaluate estimated risks of radiation induced second primary cancers (RISPC) associated with different prostate radiotherapy techniques for localised prostate cancer. A total of 83 publications were identified which employed a variety of methods to estimate RISPC risk. Of these, the 16 planning studies which specifically addressed absolute or relative second cancer risk using dose-response models were selected for inclusion within this review. There are uncertainties and limitations related to all the different methods for estimating RISPC risk. Whether or not dose models include the effects of the primary radiation beam, as well as out-of-field regions, influences estimated risks. Regarding the impact of IMRT compared to 3D-CRT, at equivalent energies, several studies suggest an increase in risk related to increased leakage contributing to out-of-field RISPC risk, although in absolute terms this increase in risk may be very small. IMRT also results in increased low dose normal tissue irradiation, but the extent to which this has been estimated to contribute to RISPC risk is variable, and may also be very small. IMRT is often delivered using 6MV photons while conventional radiotherapy often requires higher energies to achieve adequate tissue penetration, and so comparisons between IMRT and older techniques should not be restricted to equivalent energies. Proton and brachytherapy planning studies suggest very low RISPC risks associated with these techniques. Until there is sufficient clinical evidence regarding RISPC risks associated with modern irradiation techniques, the data produced from planning studies is relevant when considering which patients to irradiate, and which technique to employ.
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Affiliation(s)
- Louise Murray
- St James’s Institute of Oncology, Beckett St, Leeds LS9 7TF, UK
- University of Leeds, Leeds, UK
| | - Ann Henry
- St James’s Institute of Oncology, Beckett St, Leeds LS9 7TF, UK
- University of Leeds, Leeds, UK
| | - Peter Hoskin
- Mount Vernon Cancer Centre, Northwood, London, UK
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57
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Filippi AR, Ragona R, Fusella M, Botticella A, Fiandra C, Ricardi U. Changes in breast cancer risk associated with different volumes, doses, and techniques in female Hodgkin lymphoma patients treated with supra-diaphragmatic radiation therapy. Pract Radiat Oncol 2013; 3:216-222. [DOI: 10.1016/j.prro.2012.12.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Revised: 12/12/2012] [Accepted: 12/31/2012] [Indexed: 11/16/2022]
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58
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Werbrouck J, Ost P, Fonteyne V, De Meerleer G, De Neve W, Bogaert E, Beels L, Bacher K, Vral A, Thierens H. Early biomarkers related to secondary primary cancer risk in radiotherapy treated prostate cancer patients: IMRT versus IMAT. Radiother Oncol 2013; 107:377-81. [PMID: 23791364 DOI: 10.1016/j.radonc.2013.05.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Revised: 05/03/2013] [Accepted: 05/06/2013] [Indexed: 02/02/2023]
Abstract
PURPOSE To investigate whether rotational techniques (Volumetric Modulated Arc Therapy - VMAT) are associated with a higher risk for secondary primary malignancies compared to step-and-shoot Intensity Modulated Radiation Therapy (ss-IMRT). To this end, radiation therapy (RT) induced DNA double-strand-breaks and the resulting chromosomal damage were assessed in peripheral blood T-lymphocytes of prostate cancer (PCa) patients applying γH2AX foci and G0 micronucleus (MN) assays. METHODS AND MATERIALS The study comprised 33PCa patients. A blood sample was taken before start of therapy and after the 1st and 3rd RT fraction to determine respectively the RT-induced γH2AX foci and MN. The equivalent total body dose (D(ETB)) was calculated based on treatment planning data. RESULTS A linear dose response was obtained for γH2AX foci yields versus D(ETB) while MN showed a linear-quadratic dose response. Patients treated with large volume (LV) VMAT show a significantly higher level of induced γH2AX foci and MN compared to IMRT and small volume (SV) VMAT (p<0.01). Assuming a linear-quadratic relationship, a satisfactory correlation was found between both endpoints (R(2) 0.86). CONCLUSIONS Biomarker responses were governed by dose and irradiated volume of normal tissues. No significant differences between IMRT and rotational therapy inherent to the technique itself were observed.
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Affiliation(s)
- Joke Werbrouck
- Department of Basic Medical Sciences, Ghent University, Gent, Belgium
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59
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Exposure to low dose ionising radiation: molecular and clinical consequences. Cancer Lett 2013; 338:209-18. [PMID: 23693079 DOI: 10.1016/j.canlet.2013.05.021] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2012] [Revised: 05/10/2013] [Accepted: 05/13/2013] [Indexed: 12/19/2022]
Abstract
This review article provides a comprehensive overview of the experimental data detailing the incidence, mechanism and significance of low dose hyper-radiosensitivity (HRS). Important discoveries gained from past and present studies are mapped and highlighted to illustrate the pathway to our current understanding of HRS and the impact of HRS on the cellular response to radiation in mammalian cells. Particular attention is paid to the balance of evidence suggesting a role for DNA repair processes in the response, evidence suggesting a role for the cell cycle checkpoint processes, and evidence investigating the clinical implications/relevance of the effect.
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60
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Abbas AS, Moseley D, Kassam Z, Kim SM, Cho C. Volumetric-modulated arc therapy for the treatment of a large planning target volume in thoracic esophageal cancer. J Appl Clin Med Phys 2013; 14:4269. [PMID: 23652258 PMCID: PMC5714417 DOI: 10.1120/jacmp.v14i3.4269] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2012] [Revised: 01/28/2013] [Accepted: 01/24/2013] [Indexed: 11/23/2022] Open
Abstract
Recently, volumetric‐modulated arc therapy (VMAT) has demonstrated the ability to deliver radiation dose precisely and accurately with a shorter delivery time compared to conventional intensity‐modulated fixed‐field treatment (IMRT). We applied the hypothesis of VMAT technique for the treatment of thoracic esophageal carcinoma to determine superior or equivalent conformal dose coverage for a large thoracic esophageal planning target volume (PTV) with superior or equivalent sparing of organs‐at‐risk (OARs) doses, and reduce delivery time and monitor units (MUs), in comparison with conventional fixed‐field IMRT plans. We also analyzed and compared some other important metrics of treatment planning and treatment delivery for both IMRT and VMAT techniques. These metrics include: 1) the integral dose and the volume receiving intermediate dose levels between IMRT and VMATI plans; 2) the use of 4D CT to determine the internal motion margin; and 3) evaluating the dosimetry of every plan through patient‐specific QA. These factors may impact the overall treatment plan quality and outcomes from the individual planning technique used. In this study, we also examined the significance of using two arcs vs. a single‐arc VMAT technique for PTV coverage, OARs doses, monitor units and delivery time. Thirteen patients, stage T2‐T3 N0‐N1 (TNM AJCC 7th edn.), PTV volume median 395 cc (range 281–601 cc), median age 69 years (range 53 to 85), were treated from July 2010 to June 2011 with a four‐field (n=4) or five‐field (n=9) step‐and‐shoot IMRT technique using a 6 MV beam to a prescribed dose of 50 Gy in 20 to 25 F. These patients were retrospectively replanned using single arc (VMATI, 91 control points) and two arcs (VMATII, 182 control points). All treatment plans of the 13 study cases were evaluated using various dose‐volume metrics. These included PTV D99, PTV D95, PTV V9547.5Gy(95%), PTV mean dose, Dmax, PTV dose conformity (Van't Riet conformation number (CN)), mean lung dose, lung V20 and V5, liver V30, and Dmax to the spinal canal prv3mm. Also examined were the total plan monitor units (MUs) and the beam delivery time. Equivalent target coverage was observed with both VMAT single and two‐arc plans. The comparison of VMATI with fixed‐field IMRT demonstrated equivalent target coverage; statistically no significant difference were found in PTV D99 (p=0.47), PTV mean (p=0.12), PTV D95 and PTV V9547.5Gy (95%) (p=0.38). However, Dmax in VMATI plans was significantly lower compared to IMRT (p=0.02). The Van't Riet dose conformation number (CN) was also statistically in favor of VMATI plans (p=0.04). VMATI achieved lower lung V20 (p=0.05), whereas lung V5 (p=0.35) and mean lung dose (p=0.62) were not significantly different. The other OARs, including spinal canal, liver, heart, and kidneys showed no statistically significant differences between the two techniques. Treatment time delivery for VMATI plans was reduced by up to 55% (p=5.8E−10) and MUs reduced by up to 16% (p=0.001). Integral dose was not statistically different between the two planning techniques (p=0.99). There were no statistically significant differences found in dose distribution of the two VMAT techniques (VMATI vs. VMATII) Dose statistics for both VMAT techniques were: PTV D99 (p=0.76), PTV D95 (p=0.95), mean PTV dose (p=0.78), conformation number (CN) (p=0.26), and MUs (p=0.1). However, the treatment delivery time for VMATII increased significantly by two‐fold (p=3.0E−11) compared to VMATI. VMAT‐based treatment planning is safe and deliverable for patients with thoracic esophageal cancer with similar planning goals, when compared to standard IMRT. The key benefit for VMATI was the reduction in treatment delivery time and MUs, and improvement in dose conformality. In our study, we found no significant difference in VMATII over single‐arc VMATI for PTV coverage or OARs doses. However, we observed significant increase in delivery time for VMATII compared to VMATI. PACS number: 87.53.Kn, 87.55.‐x
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Affiliation(s)
- Ahmar S Abbas
- Stronach Regional Cancer Centre, Newmarket, ON Canada.
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Marsh JC, Ziel GE, Diaz AZ, Wendt JA, Gobole R, Turian JV. Integral dose delivered to normal brain with conventional intensity-modulated radiotherapy (IMRT) and helical tomotherapy IMRT during partial brain radiotherapy for high-grade gliomas with and without selective sparing of the hippocampus, limbic circuit a. J Med Imaging Radiat Oncol 2013; 57:378-83. [DOI: 10.1111/1754-9485.12048] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2011] [Accepted: 11/28/2012] [Indexed: 11/28/2022]
Affiliation(s)
- James C Marsh
- 21st Century Oncology of Arizona; Peoria; Arizona; USA
| | - G Ellis Ziel
- Department of Radiation Oncology; Rush University Medical Center; Chicago; Illinois; USA
| | - Aidnag Z Diaz
- Department of Radiation Oncology; Rush University Medical Center; Chicago; Illinois; USA
| | - Julie A Wendt
- Allergy, Asthma, and Immunology Associates of Arizona; Scottsdale; Arizona; USA
| | | | - Julius V Turian
- Department of Radiation Oncology; Rush University Medical Center; Chicago; Illinois; USA
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Braunstein S, Nakamura JL. Radiotherapy-induced malignancies: review of clinical features, pathobiology, and evolving approaches for mitigating risk. Front Oncol 2013; 3:73. [PMID: 23565507 PMCID: PMC3615242 DOI: 10.3389/fonc.2013.00073] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Accepted: 03/21/2013] [Indexed: 12/24/2022] Open
Abstract
One of the most significant effects of radiation therapy on normal tissues is mutagenesis, which is the basis for radiation-induced malignancies. Radiation-induced malignancies are late complications arising after radiotherapy, increasing in frequency among survivors of both pediatric and adult cancers. Genetic backgrounds harboring germline mutations in tumor suppressor genes are recognized risk factors. Some success has been found with using genome wide association studies to identify germline polymorphisms associated with susceptibility. The insights generated by genetics, epidemiology, and the development of experimental models are defining potential strategies to offer to individuals at risk for radiation-induced malignancies. Concurrent technological efforts are developing novel radiotherapy delivery to reduce irradiation of normal tissues, and thereby, to mitigate the risk of radiation-induced malignancies. The goal of this review is to discuss epidemiologic, modeling, and radiotherapy delivery data, where these lines of research intersect and their potential impact on patient care.
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Affiliation(s)
- Steve Braunstein
- Department of Radiation Oncology, University of California San FranciscoSan Francisco, CA, USA
| | - Jean L. Nakamura
- Department of Radiation Oncology, University of California San FranciscoSan Francisco, CA, USA
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Suárez C, Rodrigo JP, Mendenhall WM, Hamoir M, Silver CE, Grégoire V, Strojan P, Neumann HPH, Obholzer R, Offergeld C, Langendijk JA, Rinaldo A, Ferlito A. Carotid body paragangliomas: a systematic study on management with surgery and radiotherapy. Eur Arch Otorhinolaryngol 2013; 271:23-34. [PMID: 23420148 DOI: 10.1007/s00405-013-2384-5] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Accepted: 01/23/2013] [Indexed: 12/24/2022]
Abstract
The definitive universally accepted treatment for carotid body tumors (CBT) is surgery. The impact of surgery on cranial nerves and the carotid artery has often been underestimated. Alternatively, a few CBTs have been followed without treatment or irradiation. The goal of this study is to summarize the existing evidence concerning the efficacy and safety of surgery and external beam radiotherapy (EBRT) for CBT. Relevant articles were identified using strict criteria for systematic searches. Sixty-seven articles met the criteria which included 2,175 surgically treated patients. On the other hand, 17 articles including 127 patients treated with EBRT were found. Long-term control of the disease was obtained in 93.8% of patients who received surgical treatment and in 94.5% of the radiotherapy group. Surgery resulted in 483 (483/2,175 = 22.2%) new cranial nerve permanent deficits, whereas in the EBRT group, no new deficits were recorded (p = 0.004). The common/internal carotid artery was resected in 271 (12.5%) patients because of injury or tumor encasement, with immediate reconstruction in 212 (9.7%) patients. Three percent (60) of patients developed a permanent stroke and 1.3% (26) died due to postoperative complications. The major complications rates and the mortality after completion of the treatment also were significantly higher in surgical series compared to EBRT series. This systematic analysis highlights evidence that EBRT offers a similar chance of tumor control with lower risk of morbidity as compared to surgery in patients with CBT. This questions the traditional notion that surgery should be the mainstay of treatment.
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Affiliation(s)
- Carlos Suárez
- Department of Otolaryngology, Hospital Universitario Central de Asturias Oviedo, Oviedo, Spain
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Clinical experience transitioning from IMRT to VMAT for head and neck cancer. Med Dosim 2012; 38:171-5. [PMID: 23246253 DOI: 10.1016/j.meddos.2012.10.009] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Revised: 10/31/2012] [Accepted: 10/31/2012] [Indexed: 11/22/2022]
Abstract
To quantify clinical differences for volumetric modulated arc therapy (VMAT) versus intensity modulated radiation therapy (IMRT) in terms of dosimetric endpoints and planning and delivery time, twenty head and neck cancer patients have been considered for VMAT using Nucletron Oncentra MasterPlan delivered via an Elekta linear accelerator. Differences in planning time between IMRT and VMAT were estimated accounting for both optimization and calculation. The average delivery time per patient was obtained retrospectively using the record and verify software. For the dosimetric comparison, all contoured organs at risk (OARs) and planning target volumes (PTVs) were evaluated. Of the 20 cases considered, 14 had VMAT plans approved. Six VMAT plans were rejected due to unacceptable dose to OARs. In terms of optimization time, there was minimal difference between the two modalities. The dose calculation time was significantly longer for VMAT, 4 minutes per 358 degree arc versus 2 minutes for an entire IMRT plan. The overall delivery time was reduced by 9.2 ± 3.9 minutes for VMAT (51.4 ± 15.6%). For the dosimetric comparison of the 14 clinically acceptable plans, there was almost no statistical difference between the VMAT and IMRT. There was also a reduction in monitor units of approximately 32% from IMRT to VMAT with both modalities demonstrating comparable quality assurance results. VMAT provides comparable coverage of target volumes while sparing OARs for the majority of head and neck cases. In cases where high dose modulation was required for OARs, a clinically acceptable plan was only achievable with IMRT. Due to the long calculation times, VMAT plans can cause delays during planning but marked improvements in delivery time reduce patient treatment times and the risk of intra-fraction motion.
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Integral dose and radiation-induced secondary malignancies: comparison between stereotactic body radiation therapy and three-dimensional conformal radiotherapy. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2012. [PMID: 23202843 PMCID: PMC3524624 DOI: 10.3390/ijerph9114223] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
The aim of the present paper is to compare the integral dose received by non-tumor tissue (NTID) in stereotactic body radiation therapy (SBRT) with modified LINAC with that received by three-dimensional conformal radiotherapy (3D-CRT), estimating possible correlations between NTID and radiation-induced secondary malignancy risk. Eight patients with intrathoracic lesions were treated with SBRT, 23 Gy × 1 fraction. All patients were then replanned for 3D-CRT, maintaining the same target coverage and applying a dose scheme of 2 Gy × 32 fractions. The dose equivalence between the different treatment modalities was achieved assuming α/β = 10Gy for tumor tissue and imposing the same biological effective dose (BED) on the target (BED = 76Gy10). Total NTIDs for both techniques was calculated considering α/β = 3Gy for healthy tissue. Excess absolute cancer risk (EAR) was calculated for various organs using a mechanistic model that includes fractionation effects. A paired two-tailed Student t-test was performed to determine statistically significant differences between the data (p ≤ 0.05). Our study indicates that despite the fact that for all patients integral dose is higher for SBRT treatments than 3D-CRT (p = 0.002), secondary cancer risk associated to SBRT patients is significantly smaller than that calculated for 3D-CRT (p = 0.001). This suggests that integral dose is not a good estimator for quantifying cancer induction. Indeed, for the model and parameters used, hypofractionated radiotherapy has the potential for secondary cancer reduction. The development of reliable secondary cancer risk models seems to be a key issue in fractionated radiotherapy. Further assessments of integral doses received with 3D-CRT and other special techniques are also strongly encouraged.
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Lafond C, Gassa F, Odin C, Dréan G, Even J, De Crevoisier R, Pommier P, Manens JP, Biston MC. Comparison between two treatment planning systems for volumetric modulated arc therapy optimization for prostate cancer. Phys Med 2012; 30:2-9. [PMID: 23116552 DOI: 10.1016/j.ejmp.2012.10.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Revised: 10/03/2012] [Accepted: 10/09/2012] [Indexed: 11/29/2022] Open
Abstract
PURPOSE To investigate the performances of two commercial treatment planning systems (TPS) for Volumetric Modulated Arc Therapy (VMAT) optimization regarding prostate cancer. The TPS were compared in terms of dose distributions, treatment delivery parameters and quality control results. MATERIALS AND METHODS For ten patients, two VMAT plans were generated: one with Monaco TPS (Elekta) and one with Pinnacle TPS (Philips Medical Systems). The total prescribed dose was 78 Gy delivered in one 360° arc with a Synergy(®) linear accelerator equipped with a MLCi2(®). RESULTS VMAT with Monaco provided better homogeneity and conformity indexes but lower mean dose to PTVs than Pinnacle. For the bladder wall (p = 0.019), the femoral heads (p = 0.017), and healthy tissues (p = 0.005), significantly lower mean doses were found using Monaco. For the rectal wall, VMAT with Pinnacle provided a significantly (p = 0.047) lower mean dose, and lower dose into 50% of the volume (p = 0.047) compared to Monaco. Despite a greater number of monitor units (factor 1.5) for Monaco TPS, the total treatment time was equivalent to that of Pinnacle. The treatment delivery parameter analysis showed larger mean MLC area for Pinnacle and lower mean dose rate compared to Monaco. The quality control results gave a high passing rate (>97.4%) for the gamma index for both TPS but Monaco provided slightly better results. CONCLUSION For prostate cancer patients, VMAT treatment plans obtained with Monaco and Pinnacle offered clinically acceptable dose distributions. Further investigations are in progress to confirm the performances of the two TPS for irradiating more complex volumes.
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Affiliation(s)
- Caroline Lafond
- Radiation Oncology Department, Centre Eugène Marquis, Rennes, France; Université de Rennes 1, LTSI, France; INSERM, U1099, France.
| | - Frédéric Gassa
- Radiation Oncology Department, Centre Léon Bérard, Lyon, France
| | - Christophe Odin
- Institut of Physics of Rennes, IPR/UMR CNRS 6251, University of Rennes I, Rennes, France
| | - Gaël Dréan
- Université de Rennes 1, LTSI, France; INSERM, U1099, France
| | - Justine Even
- Radiation Oncology Department, Centre Eugène Marquis, Rennes, France
| | - Renaud De Crevoisier
- Radiation Oncology Department, Centre Eugène Marquis, Rennes, France; Université de Rennes 1, LTSI, France; INSERM, U1099, France
| | - Pascal Pommier
- Radiation Oncology Department, Centre Léon Bérard, Lyon, France
| | - Jean-Pierre Manens
- Radiation Oncology Department, Centre Eugène Marquis, Rennes, France; Université de Rennes 1, LTSI, France; INSERM, U1099, France
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Rechner LA, Howell RM, Zhang R, Etzel C, Lee AK, Newhauser WD. Risk of radiogenic second cancers following volumetric modulated arc therapy and proton arc therapy for prostate cancer. Phys Med Biol 2012; 57:7117-32. [PMID: 23051714 DOI: 10.1088/0031-9155/57/21/7117] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Prostate cancer patients who undergo radiotherapy are at an increased risk to develop a radiogenic second cancer. Proton therapy has been shown to reduce the predicted risk of second cancer when compared to intensity modulated radiotherapy. However, it is unknown if this is also true for the rotational therapies proton arc therapy and volumetric modulated arc therapy (VMAT). The objective of this study was to compare the predicted risk of cancer following proton arc therapy and VMAT for prostate cancer. Proton arc therapy and VMAT plans were created for three patients. Various risk models were combined with the dosimetric data (therapeutic and stray dose) to predict the excess relative risk (ERR) of cancer in the bladder and rectum. Ratios of ERR values (RRR) from proton arc therapy and VMAT were calculated. RRR values ranged from 0.74 to 0.99, and all RRR values were shown to be statistically less than 1, except for the value calculated with the linear-non-threshold risk model. We conclude that the predicted risk of cancer in the bladder or rectum following proton arc therapy for prostate cancer is either less than or approximately equal to the risk following VMAT, depending on which risk model is applied.
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Affiliation(s)
- Laura A Rechner
- Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
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Abstract
We present a method for improving the delivery efficiency of VMAT by extending the recently published VMAT treatment planning algorithm vmerge to automatically generate optimal partial-arc plans. A high-quality initial plan is created by solving a convex multicriteria optimization problem using 180 equi-spaced beams. This initial plan is used to form a set of dose constraints, and a set of partial-arc plans is created by searching the space of all possible partial-arc plans that satisfy these constraints. For each partial-arc, an iterative fluence map merging and sequencing algorithm (vmerge) is used to improve the delivery efficiency. Merging continues as long as the dose quality is maintained above a user-defined threshold. The final plan is selected as the partial-arc with the lowest treatment time. The complete algorithm is called pmerge. Partial-arc plans are created using pmerge for a lung, liver and prostate case, with final treatment times of 127, 245 and 147 . Treatment times using full arcs with vmerge are 211, 357 and 178 s. The mean doses to the critical structures for the vmerge and pmerge plans are kept within 5% of those in the initial plan, and the target volume covered by the prescription isodose is maintained above 98% for the pmerge and vmerge plans. Additionally, we find that the angular distribution of fluence in the initial plans is predictive of the start and end angles of the optimal partial-arc. We conclude that VMAT delivery efficiency can be improved by employing partial-arcs without compromising dose quality, and that partial-arcs are most applicable to cases with non-centralized targets.
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Affiliation(s)
- Jeremiah Wala
- Department of Radiation Oncology, Massachusetts General Hospital, 30 Fruit Street, Boston, MA 02114, USA.
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Nguyen BT, Hornby C, Kron T, Cramb J, Rolfo A, Pham D, Haworth A, Tai KH, Foroudi F. Optimising the dosimetric quality and efficiency of post-prostatectomy radiotherapy: a planning study comparing the performance of volumetric-modulated arc therapy (VMAT) with an optimised seven-field intensity-modulated radiotherapy (IMRT) technique. J Med Imaging Radiat Oncol 2012; 56:211-9. [PMID: 22498196 DOI: 10.1111/j.1754-9485.2011.02324.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
PURPOSE The purpose of this study was to compare and evaluate radiotherapy treatment plans using volumetric modulated arc therapy (VMAT) and intensity modulated radiotherapy (IMRT) for post-prostatectomy radiotherapy. METHODS AND MATERIALS The quality of radiotherapy plans for 10 patients planned and treated with a seven-field IMRT technique for biochemical failure post-prostatectomy were subsequently compared with 10 prospectively planned single-arc VMAT plans using the same computed tomography data set and treatment planning software. Plans were analysed using parameters to assess for target volume coverage, dose to organs at risk (OAR), biological outcomes, dose conformity and homogeneity, as well as the total monitor units (MU), planning and treatment efficiency. RESULTS The mean results for the study population are reported for the purpose of comparison. For IMRT, the median dose to the planning target volume, V(95%) and D(95%) was 71.1 Gy, 98.9% and 68.3 Gy compared with 71.2 Gy, 99.2% and 68.6 Gy for VMAT. There was no significant difference in the conformity index or homogeneity index. The VMAT plans achieved better sparing of the rectum and the left and right femora with a reduction in the median dose by 7.9, 6.3 and 3.6 Gy, respectively. The total number of monitor units (MU) was reduced by 24% and treatment delivery time by an estimated 3 min per fraction without a significant increase in planning requirements. CONCLUSIONS VMAT can achieve post-prostatectomy radiotherapy plans of comparable quality to IMRT with the potential to reduce dose to OAR and improve the efficiency of treatment delivery.
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Affiliation(s)
- Brandon T Nguyen
- Division of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, Locked Bag 1, A’Beckett Street, Vic. 8006, Australia.
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Foroudi F, Wilson L, Bressel M, Haworth A, Hornby C, Pham D, Cramb J, Gill S, Tai KH, Kron T. A dosimetric comparison of 3D conformal vs intensity modulated vs volumetric arc radiation therapy for muscle invasive bladder cancer. Radiat Oncol 2012; 7:111. [PMID: 22824133 PMCID: PMC3444363 DOI: 10.1186/1748-717x-7-111] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Accepted: 07/03/2012] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND To compare 3 Dimensional Conformal radiotherapy (3D-CRT) with Intensity Modulated Radiotherapy (IMRT) with Volumetric-Modulated Arc Therapy (VMAT) for bladder cancer. METHODS Radiotherapy plans for 15 patients with T2-T4N0M0 bladder cancer were prospectively developed for 3-DCRT, IMRT and VMAT using Varian Eclipse planning system. The same radiation therapist carried out all planning and the same clinical dosimetric constraints were used. 10 of the patients with well localised tumours had a simultaneous infield boost (SIB) of the primary tumour planned for both IMRT and VMAT. Tumour control probabilities and normal tissue complication probabilities were calculated. RESULTS Mean planning time for 3D-CRT, IMRT and VMAT was 30.0, 49.3, and 141.0 minutes respectively. The mean PTV conformity (CI) index for 3D-CRT was 1.32, for IMRT 1.05, and for VMAT 1.05. The PTV Homogeneity (HI) index was 0.080 for 3D-CRT, 0.073 for IMRT and 0.086 for VMAT. Tumour control and normal tissue complication probabilities were similar for 3D-CRT, IMRT and VMAT. The mean monitor units were 267 (range 250-293) for 3D-CRT; 824 (range 641-1083) for IMRT; and 403 (range 333-489) for VMAT (P < 0.05). Average treatment delivery time were 2:25min (range 2:01-3:09) for 3D-CRT; 4:39 (range 3:41-6:40) for IMRT; and 1:14 (range 1:13-1:14) for VMAT. In selected patients, the SIB did not result in a higher dose to small bowel or rectum. CONCLUSIONS VMAT is associated with similar dosimetric advantages as IMRT over 3D-CRT for muscle invasive bladder cancer. VMAT is associated with faster delivery times and less number of mean monitor units than IMRT. SIB is feasible in selected patients with localized tumours.
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Affiliation(s)
- Farshad Foroudi
- Division of Radiation Oncology, Peter MacCallum Cancer Center, Peter MacCallum Cancer Institute, St Andrews Place, East Melbourne, VIC, 3002, Australia
| | - Lesley Wilson
- Radiation Therapy Services, Peter MacCallum Cancer Center, Melbourne, VIC, Australia
| | - Mathias Bressel
- Biostatistics and Clinical Trials, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
| | - Annette Haworth
- Physical Sciences, Peter MacCallum Cancer Center, Melbourne, VIC, Australia
| | - Colin Hornby
- Radiation Therapy Services, Peter MacCallum Cancer Center, Melbourne, VIC, Australia
| | - Daniel Pham
- Radiation Therapy Services, Peter MacCallum Cancer Center, Melbourne, VIC, Australia
| | - Jim Cramb
- Physical Sciences, Peter MacCallum Cancer Center, Melbourne, VIC, Australia
| | - Suki Gill
- Division of Radiation Oncology, Peter MacCallum Cancer Center, Peter MacCallum Cancer Institute, St Andrews Place, East Melbourne, VIC, 3002, Australia
| | - Keen Hun Tai
- Division of Radiation Oncology, Peter MacCallum Cancer Center, Peter MacCallum Cancer Institute, St Andrews Place, East Melbourne, VIC, 3002, Australia
| | - Tomas Kron
- Physical Sciences, Peter MacCallum Cancer Center, Melbourne, VIC, Australia
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Timlin C, Houston M, Jones B. Malignant induction probability maps for radiotherapy using X-ray and proton beams. Br J Radiol 2012; 84 Spec No 1:S70-8. [PMID: 22374550 DOI: 10.1259/bjr/70190973] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
The aim of this study was to display malignant induction probability (MIP) maps alongside dose distribution maps for radiotherapy using X-ray and charged particles such as protons. Dose distributions for X-rays and protons are used in an interactive MATLAB® program (MathWorks, Natick, MA). The MIP is calculated using a published linear quadratic model, which incorporates fractionation effects, cell killing and cancer induction as a function of dose, as well as relative biological effect. Two virtual situations are modelled: (a) a tumour placed centrally in a cubic volume of normal tissue and (b) the same tumour placed closer to the skin surface. The MIP is calculated for a variety of treatment field options. The results show that, for protons, the MIP increases with field numbers. In such cases, proton MIP can be higher than that for X-rays. Protons produce the lowest MIPs for superficial targets because of the lack of exit dose. The addition of a dose bath to all normal tissues increases the MIP by up to an order of magnitude. This exploratory study shows that it is possible to achieve three-dimensional displays of carcinogenesis risk. The importance of treatment geometry, including the length and volume of tissue traversed by each beam, can all influence MIP. Reducing the volume of tissue irradiated is advantageous, as reducing the number of cells at risk reduces the total MIP. This finding lends further support to the use of treatment gantries as well as the use of simpler field arrangements for particle therapy provided normal tissue tolerances are respected.
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Affiliation(s)
- C Timlin
- Particle Therapy Cancer Research Institute, Denys Wilkinson Building, Oxford, UK.
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Blais AR, Lederer E, Oliver M, Leszczynski K. Static and rotational step-and-shoot IMRT treatment plans for the prostate: A risk comparison study. Med Phys 2012; 39:1069-78. [DOI: 10.1118/1.3679338] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Marsh JC, Godbole R, Diaz A, Herskovic A, Turian J. Feasibility of cognitive sparing approaches in children with intracranial tumors requiring partial brain radiotherapy: A dosimetric study using tomotherapy. ACTA ACUST UNITED AC 2012. [DOI: 10.7243/2049-7962-1-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Teoh M, Clark CH, Wood K, Whitaker S, Nisbet A. Volumetric modulated arc therapy: a review of current literature and clinical use in practice. Br J Radiol 2011; 84:967-96. [PMID: 22011829 DOI: 10.1259/bjr/22373346] [Citation(s) in RCA: 431] [Impact Index Per Article: 33.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Volumetric modulated arc therapy (VMAT) is a novel radiation technique, which can achieve highly conformal dose distributions with improved target volume coverage and sparing of normal tissues compared with conventional radiotherapy techniques. VMAT also has the potential to offer additional advantages, such as reduced treatment delivery time compared with conventional static field intensity modulated radiotherapy (IMRT). The clinical worldwide use of VMAT is increasing significantly. Currently the majority of published data on VMAT are limited to planning and feasibility studies, although there is emerging clinical outcome data in several tumour sites. This article aims to discuss the current use of VMAT techniques in practice and review the available data from planning and clinical outcome studies in various tumour sites including prostate, pelvis (lower gastrointestinal, gynaecological), head and neck, thoracic, central nervous system, breast and other tumour sites.
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Affiliation(s)
- M Teoh
- Department of Oncology, St Luke's Cancer Centre, Royal Surrey County Hospital, Guildford, Surrey, UK.
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75
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Yu CC, Hsu FY, Yu WH, Liu MT, Huang SS. Assessing doses of radiotherapy with the risk of developing cancer in the head and neck. RADIAT MEAS 2011. [DOI: 10.1016/j.radmeas.2011.09.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Pasler M, Georg D, Wirtz H, Lutterbach J. Effect of photon-beam energy on VMAT and IMRT treatment plan quality and dosimetric accuracy for advanced prostate cancer. Strahlenther Onkol 2011; 187:792-8. [PMID: 22127357 DOI: 10.1007/s00066-011-1150-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Accepted: 09/13/2011] [Indexed: 11/25/2022]
Abstract
PURPOSE The goal of the research was to evaluate treatment plan quality and dosimetric accuracy of volumetric modulated arc therapy (VMAT) and intensity-modulated radiotherapy (IMRT) plans using 6, 10, and 15 MV photon beams for prostate cancer including lymph nodes. METHODS In this retrospective study, VMAT and IMRT plans were generated with the Pinnacle© treatment planning system (TPS) (V9.0) for 10 prostate cancer cases. Each plan consisted of two target volumes: PTV(B) included the prostate bed, PTV(PC+LN) contained PTV(B) and lymph nodes. For plan evaluation statistics, the homogeneity index, conformity index, mean doses, and near-max doses to organs at risk (OAR) were analyzed. Treatment time and number of monitor units were assessed to compare delivery efficiency. Dosimetric plan verification was performed with a 2D ionization chamber array placed in a full scatter phantom. RESULTS No differences were found for target and OAR parameters in low and high energy photon beam plans for both VMAT and IMRT. A slightly higher low dose volume was detected for 6 MV VMAT plans (normal tissue: D(mean) = 16.47 Gy) compared to 10 and 15 MV VMAT plans (D(mean) = 15.90 Gy and 15.74 Gy, respectively), similar to the findings in IMRT. In VMAT, > 96% of detector points passed the 3%/ 3 mm γ criterion; marginally better accuracy was found in IMRT (> 97%). CONCLUSION For static and rotational IMRT, 15 MV photons did not show advantages over 6 and 10 MV high energy photon beams in large volume pelvic plans. For the investigated TPS and linac combination, 10 MV photon beams can be used as the general purpose energy for intensity modulation.
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Affiliation(s)
- Marlies Pasler
- Lake Constance Radiation Oncology Center Singen-Friedrichshafen, Singen, Germany
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Sountoulides P, Koletsas N, Kikidakis D, Paschalidis K, Sofikitis N. Secondary malignancies following radiotherapy for prostate cancer. Ther Adv Urol 2011; 2:119-25. [PMID: 21789089 DOI: 10.1177/1756287210374462] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Human exposure to sources of radiation as well as the use of radiation-derived therapeutic and diagnostic modalities for medical reasons has been ongoing for the last 60 years or so. The carcinogenetic effect of radiation either due to accidental exposure or use of radiation for the treatment of cancer has been undoubtedly proven during the last decades. The role of radiation therapy in the treatment of patients with prostate cancer is constantly increasing as less-invasive treatment modalities are sought for the management of this widely, prevalent disease. Moreover the wide adoption of screening for prostate cancer has led to a decrease in the average age that patients are diagnosed with prostate cancer. Screening has also resulted in the diagnosis of low-grade, less-aggressive prostate cancers which would probably never lead to complications or death from the disease. Radiotherapy for prostate cancer has been linked to the late occurrence of second malignancies both in the true pelvis and outside the targeted area due to low-dose radiation scatter. Secondary malignancies following prostate irradiation include predominantly bladder cancer and, to a lesser extent, colon cancer. Those secondary radiation-induced bladder tumors are usually aggressive and sometimes lethal. Care should be given to the long-term follow up of patients under radiation therapy for prostate cancer, while the indications for its use in certain cases should be reconsidered.
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Affiliation(s)
- Petros Sountoulides
- Urology Department, General Hospital of Veria, 15-17 Agiou Evgeniou Street, 55133, Thessaloniki, Greece
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Hussein M, Aldridge S, Guerrero Urbano T, Nisbet A. The effect of 6 and 15 MV on intensity-modulated radiation therapy prostate cancer treatment: plan evaluation, tumour control probability and normal tissue complication probability analysis, and the theoretical risk of secondary induced malignancies. Br J Radiol 2011; 85:423-32. [PMID: 22010028 DOI: 10.1259/bjr/24514638] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
OBJECTIVE The aim of this study was to investigate the effect of 6 and 15-MV photon energies on intensity-modulated radiation therapy (IMRT) prostate cancer treatment plan outcome and to compare the theoretical risks of secondary induced malignancies. METHODS Separate prostate cancer IMRT plans were prepared for 6 and 15-MV beams. Organ-equivalent doses were obtained through thermoluminescent dosemeter measurements in an anthropomorphic Aldersen radiation therapy human phantom. The neutron dose contribution at 15 MV was measured using polyallyl-diglycol-carbonate neutron track etch detectors. Risk coefficients from the International Commission on Radiological Protection Report 103 were used to compare the risk of fatal secondary induced malignancies in out-of-field organs and tissues for 6 and 15 MV. For the bladder and the rectum, a comparative evaluation of the risk using three separate models was carried out. Dose-volume parameters for the rectum, bladder and prostate planning target volume were evaluated, as well as normal tissue complication probability (NTCP) and tumour control probability calculations. RESULTS There is a small increased theoretical risk of developing a fatal cancer from 6 MV compared with 15 MV, taking into account all the organs. Dose-volume parameters for the rectum and bladder show that 15 MV results in better volume sparing in the regions below 70 Gy, but the volume exposed increases slightly beyond this in comparison with 6 MV, resulting in a higher NTCP for the rectum of 3.6% vs 3.0% (p=0.166). CONCLUSION The choice to treat using IMRT at 15 MV should not be excluded, but should be based on risk vs benefit while considering the age and life expectancy of the patient together with the relative risk of radiation-induced cancer and NTCPs.
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Affiliation(s)
- M Hussein
- Department of Medical Physics, St Luke's Cancer Centre, Royal Surrey County Hospital NHS Foundation Trust, Guildford, UK.
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Takam R, Bezak E, Marcu LG, Yeoh E. Out-of-Field Neutron and Leakage Photon Exposures and the Associated Risk of Second Cancers in High-Energy Photon Radiotherapy: Current Status. Radiat Res 2011; 176:508-20. [DOI: 10.1667/rr2606.1] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Ge Y, Faddegon BA. Study of intensity-modulated photon–electron radiation therapy using digital phantoms. Phys Med Biol 2011; 56:6693-708. [DOI: 10.1088/0031-9155/56/20/012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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81
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Fogarty GB, Ng D, Liu G, Haydu LE, Bhandari N. Volumetric modulated arc therapy is superior to conventional intensity modulated radiotherapy--a comparison among prostate cancer patients treated in an Australian centre. Radiat Oncol 2011; 6:108. [PMID: 21892944 PMCID: PMC3179721 DOI: 10.1186/1748-717x-6-108] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Accepted: 09/05/2011] [Indexed: 02/08/2023] Open
Abstract
Background Radiotherapy technology is expanding rapidly. Volumetric Modulated Arc Therapy (VMAT) technologies such as RapidArc® (RA) may be a more efficient way of delivering intensity-modulated radiotherapy-like (IM) treatments. This study is an audit of the RA experience in an Australian department with a planning and economic comparison to IM. Methods 30 consecutive prostate cancer patients treated radically with RA were analyzed. Eight RA patients treated definitively were then completely re-planned with 3D conformal radiotherapy (3D); and a conventional sliding window IM technique; and a new RA plan. The acceptable plans and their treatment times were compared and analyzed for any significant difference. Differences in staff costs of treatment were computed and analyzed. Results Thirty patients had been treated to date with eight being treated definitely to at least 74 Gy, nine post high dose brachytherapy (HDR) to 50.4Gy and 13 post prostatectomy to at least 64Gy. All radiotherapy courses were completed with no breaks. Acute rectal toxicity by the RTOG criteria was acceptable with 22 having no toxicity, seven with grade 1 and one had grade 2. Of the eight re-planned patients, none of the 3D (three-dimensional conformal radiotherapy) plans were acceptable based on local guidelines for dose to organs at risk. There was no statistically significant difference in planning times between IM and RA (p = 0.792). IM had significantly greater MUs per fraction (1813.9 vs 590.2 p < 0.001), total beam time per course (5.2 vs 3.1 hours, p = 0.001) and average treatment staff cost per patient radiotherapy course ($AUD489.91 vs $AUD315.66, p = 0.001). The mean saving in treatment staff cost for RA treatment was $AUD174.25 per patient. Conclusions 3D was incapable of covering a modern radiotherapy volume for the radical treatment of prostate cancer. These volumes can be treated via conventional IM and RA. RA was significantly more efficient, safe and cost effective than IM. VMAT technologies are a superior way of delivering IM-like treatments.
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Affiliation(s)
- Gerald B Fogarty
- Radiation Oncology Department, Mater Hospital, Crows Nest, NSW, Australia.
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82
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Winkfield KM, Niemierko A, Bussière MR, Crowley EM, Napolitano BN, Beaudette KP, Loeffler JS, Shih HA. Modeling Intracranial Second Tumor Risk and Estimates of Clinical Toxicity with Various Radiation Therapy Techniques for Patients with Pituitary Adenoma. Technol Cancer Res Treat 2011; 10:243-51. [DOI: 10.7785/tcrt.2012.500199] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
This study was designed to estimate the risk of radiation-associated tumors and clinical toxicity in the brain following fractionated radiation treatment of pituitary adenoma. A standard case of a patient with a pituitary adenoma was planned using 8 different dosimetric techniques. Total dose was 50.4 Gy (GyE) at daily fractionation of 1.8 Gy (GyE). All methods utilized the same CT simulation scan with designated target and normal tissue volumes. The excess risk of radiation-associated second tumors in the brain was calculated using the corresponding dose-volume histograms for the whole brain and based on the data published by the United Nation Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) and a risk model proposed by Schneider. The excess number of second tumor cases per 10,000 patients per year following radiation is 9.8 for 2-field photons, 18.4 with 3-field photons, 20.4 with photon intensity modulated radiation therapy (IMRT), and 25 with photon stereotactic radiotherapy (SRT). Proton radiation resulted in the following excess second tumor risks: 2-field = 5.1, 3-field = 12, 4-field = 15, 5-field = 16. Temporal lobe toxicity was highest for the 2-field photon plan. Proton radiation therapy achieves the best therapeutic ratio when evaluating plans for the treatment of pituitary adenoma. Temporal lobe toxicity can be reduced through the use of multiple fields but is achieved at the expense of exposing a larger volume of normal brain to radiation. Limiting the irradiated volume of normal brain by reducing the number of treatment fields is desirable to minimize excess risk of radiation-associated second tumors.
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Affiliation(s)
- K. M. Winkfield
- Department of Radiation Oncology Massachusetts General Hospital 100 Blossom Street, Cox 3, Boston, MA 02114, USA
| | - A. Niemierko
- Department of Radiation Oncology Massachusetts General Hospital 100 Blossom Street, Cox 3, Boston, MA 02114, USA
| | - M. R. Bussière
- Department of Radiation Oncology Massachusetts General Hospital 100 Blossom Street, Cox 3, Boston, MA 02114, USA
| | - E. M. Crowley
- Department of Radiation Oncology Massachusetts General Hospital 100 Blossom Street, Cox 3, Boston, MA 02114, USA
| | - B. N. Napolitano
- Department of Radiation Oncology Massachusetts General Hospital 100 Blossom Street, Cox 3, Boston, MA 02114, USA
| | - K. P. Beaudette
- Department of Radiation Oncology Massachusetts General Hospital 100 Blossom Street, Cox 3, Boston, MA 02114, USA
| | - J. S. Loeffler
- Department of Radiation Oncology Massachusetts General Hospital 100 Blossom Street, Cox 3, Boston, MA 02114, USA
| | - H. A. Shih
- Department of Radiation Oncology Massachusetts General Hospital 100 Blossom Street, Cox 3, Boston, MA 02114, USA
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83
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Taylor ML, Kron T. Consideration of the radiation dose delivered away from the treatment field to patients in radiotherapy. J Med Phys 2011; 36:59-71. [PMID: 21731221 PMCID: PMC3119954 DOI: 10.4103/0971-6203.79686] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2010] [Revised: 12/30/2010] [Accepted: 01/11/2011] [Indexed: 01/01/2023] Open
Abstract
Radiation delivery to cancer patients for radiotherapy is invariably accompanied by unwanted radiation to other parts of the patient's body. Traditionally, considerable effort has been made to calculate and measure the radiation dose to the target as well as to nearby critical structures. Only recently has attention been focused also on the relatively low doses that exist far from the primary radiation beams. In several clinical scenarios, such doses have been associated with cardiac toxicity as well as an increased risk of secondary cancer induction. Out-of-field dose is a result of leakage and scatter and generally difficult to predict accurately. The present review aims to present existing data, from measurements and calculations, and discuss its implications for radiotherapy.
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Affiliation(s)
- Michael L. Taylor
- School of Applied Sciences, RMIT University, Melbourne, Australia
- Physical Sciences, Peter MacCallum Cancer Centre, Melbourne, Australia
| | - Tomas Kron
- School of Applied Sciences, RMIT University, Melbourne, Australia
- Physical Sciences, Peter MacCallum Cancer Centre, Melbourne, Australia
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84
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Daşu A, Toma-Daşu I, Franzén L, Widmark A, Nilsson P. Secondary Malignancies From Prostate Cancer Radiation Treatment: A Risk Analysis of the Influence of Target Margins and Fractionation Patterns. Int J Radiat Oncol Biol Phys 2011; 79:738-46. [DOI: 10.1016/j.ijrobp.2009.12.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2009] [Revised: 11/27/2009] [Accepted: 12/01/2009] [Indexed: 12/31/2022]
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85
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Volumetric Arc Therapy and Intensity-Modulated Radiotherapy for Primary Prostate Radiotherapy With Simultaneous Integrated Boost to Intraprostatic Lesion With 6 and 18 MV: A Planning Comparison Study. Int J Radiat Oncol Biol Phys 2011; 79:920-6. [PMID: 20675077 DOI: 10.1016/j.ijrobp.2010.04.025] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2009] [Revised: 04/19/2010] [Accepted: 04/29/2010] [Indexed: 12/14/2022]
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86
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Clavel S, Nguyen DHA, Fortin B, Després P, Khaouam N, Donath D, Soulières D, Guertin L, Nguyen-Tan PF. Simultaneous integrated boost using intensity-modulated radiotherapy compared with conventional radiotherapy in patients treated with concurrent carboplatin and 5-fluorouracil for locally advanced oropharyngeal carcinoma. Int J Radiat Oncol Biol Phys 2011; 82:582-9. [PMID: 21277695 DOI: 10.1016/j.ijrobp.2010.10.061] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2010] [Revised: 10/03/2010] [Accepted: 10/13/2010] [Indexed: 10/18/2022]
Abstract
PURPOSE To compare, in a retrospective study, the toxicity and efficacy of simultaneous integrated boost using intensity-modulated radiotherapy (IMRT) vs. conventional radiotherapy (CRT) in patients treated with concomitant carboplatin and 5-fluorouracil for locally advanced oropharyngeal cancer. METHODS AND MATERIALS Between January 2000 and December 2007, 249 patients were treated with definitive chemoradiation. One hundred patients had 70 Gy in 33 fractions using IMRT, and 149 received CRT at 70 Gy in 35 fractions. Overall survival, disease-free survival, and locoregional control were estimated using the Kaplan-Meier method. RESULTS Median follow-up was 42 months. Three-year actuarial rates for locoregional control, disease-free survival, and overall survival were 95.1% vs. 84.4% (p = 0.005), 85.3% vs. 69.3% (p = 0.001), and 92.1% vs. 75.2% (p < 0.001) for IMRT and CRT, respectively. The benefit of the radiotherapy regimen on outcomes was also observed with a Cox multivariate analysis. Intensity-modulated radiotherapy was associated with less acute dermatitis and less xerostomia at 6, 12, 24, and 36 months. CONCLUSIONS This study suggests that simultaneous integrated boost using IMRT is associated with favorable locoregional control and survival rates with less xerostomia and acute dermatitis than CRT when both are given concurrently with chemotherapy.
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Affiliation(s)
- Sébastien Clavel
- Department of Radiation Oncology, Centre Hospitalier de l'Université de Montréal, Montréal, QC, Canada.
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87
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Cashmore J, Ramtohul M, Ford D. Lowering whole-body radiation doses in pediatric intensity-modulated radiotherapy through the use of unflattened photon beams. Int J Radiat Oncol Biol Phys 2010; 80:1220-7. [PMID: 21167659 DOI: 10.1016/j.ijrobp.2010.10.002] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2010] [Revised: 09/23/2010] [Accepted: 10/07/2010] [Indexed: 11/29/2022]
Abstract
PURPOSE Intensity modulated radiotherapy (IMRT) has been linked with an increased risk of secondary cancer induction due to the extra leakage radiation associated with delivery of these techniques. Removal of the flattening filter offers a simple way of reducing head leakage, and it may be possible to generate equivalent IMRT plans and to deliver these on a standard linear accelerator operating in unflattened mode. METHODS AND MATERIALS An Elekta Precise linear accelerator has been commissioned to operate in both conventional and unflattened modes (energy matched at 6 MV) and a direct comparison made between the treatment planning and delivery of pediatric intracranial treatments using both approaches. These plans have been evaluated and delivered to an anthropomorphic phantom. RESULTS Plans generated in unflattened mode are clinically identical to those for conventional IMRT but can be delivered with greatly reduced leakage radiation. Measurements in an anthropomorphic phantom at clinically relevant positions including the thyroid, lung, ovaries, and testes show an average reduction in peripheral doses of 23.7%, 29.9%, 64.9%, and 70.0%, respectively, for identical plan delivery compared to conventional IMRT. CONCLUSIONS IMRT delivery in unflattened mode removes an unwanted and unnecessary source of scatter from the treatment head and lowers leakage doses by up to 70%, thereby reducing the risk of radiation-induced second cancers. Removal of the flattening filter is recommended for IMRT treatments.
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Affiliation(s)
- Jason Cashmore
- University Hospital Birmingham, Edgbaston, Birmingham, UK.
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88
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Domingo C, García-Fusté M, Morales E, Amgarou K, Terrón J, Roselló J, Brualla L, Nuñez L, Colmenares R, Gómez F, Hartmann G, Sánchez-Doblado F, Fernández F. Neutron spectrometry and determination of neutron ambient dose equivalents in different LINAC radiotherapy rooms. RADIAT MEAS 2010. [DOI: 10.1016/j.radmeas.2010.05.023] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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89
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Gómez F, Sánchez-Doblado F, Iglesias A, Domingo C. Active on-line detector for in-room radiotherapy neutron measurements. RADIAT MEAS 2010. [DOI: 10.1016/j.radmeas.2010.05.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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90
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Domingo C, Gómez F, Sánchez-Doblado F, Hartmann G, Amgarou K, García-Fusté M, Romero M, Böttger R, Nolte R, Wissmann F, Zimbal A, Schuhmacher H. Calibration of a neutron detector based on single event upset of SRAM memories. RADIAT MEAS 2010. [DOI: 10.1016/j.radmeas.2010.08.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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91
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Huang J, Kestin LL, Ye H, Wallace M, Martinez AA, Vicini FA. Analysis of second malignancies after modern radiotherapy versus prostatectomy for localized prostate cancer. Radiother Oncol 2010; 98:81-6. [PMID: 20951450 DOI: 10.1016/j.radonc.2010.09.012] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2010] [Revised: 09/16/2010] [Accepted: 09/20/2010] [Indexed: 12/27/2022]
Abstract
PURPOSE To clarify the risk of developing second primary cancers (SPCs) after radiotherapy (RT) versus prostatectomy for localized prostate cancer (PCa) in the modern era. METHODS The RT cohort consisted of 2120 patients matched on a 1:1 basis with surgical patients according to age and follow-up time. RT techniques consisted of conventional or two-dimensional RT (2DRT, 36%), three-dimensional conformal RT and/or intensity modulated RT (3DCRT/IMRT, 29%), brachytherapy (BT, 16%), and a combination of 2DRT and BT (BT boost, 19%). RESULTS The overall SPC risk was not significantly different between the matched-pair (HR 1.14, 95% CI 0.94-1.39), but the risk became significant >5years or >10years after RT (HR 1.86, 95% CI 1.36-2.55; HR 4.94, 95% CI 2.18-11.2, respectively). The most significant sites of increased risk were bladder, lymphoproliferative, and sarcoma. Of the different RT techniques, only 2DRT was associated with a significantly higher risk (HR 1.76, 95% CI 1.32-2.35), but not BT boost (HR 0.83, 95% CI 0.50-1.38), 3DCRT/IMRT (HR 0.81, 95% CI 0.55-1.21), or BT (HR 0.53, 95% CI 0.28-1.01). CONCLUSIONS Radiation-related SPC risk varies depending on the RT technique and may be reduced by using BT, BT boost, or 3DCRT/IMRT.
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Affiliation(s)
- Jiayi Huang
- Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, MI, USA
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92
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Ruben JD, Lancaster CM, Jones P, Smith RL. A comparison of out-of-field dose and its constituent components for intensity-modulated radiation therapy versus conformal radiation therapy: implications for carcinogenesis. Int J Radiat Oncol Biol Phys 2010; 81:1458-64. [PMID: 20950947 DOI: 10.1016/j.ijrobp.2010.08.008] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2010] [Revised: 07/27/2010] [Accepted: 08/02/2010] [Indexed: 12/13/2022]
Abstract
PURPOSE To investigate differences in scatter and leakage between 6-MV intensity-modulated radiation therapy (IMRT) and three-dimensional conformal radiation therapy (3DCRT); to describe the relative contributions of internal patient scatter, collimator scatter, and head leakage; and to discuss implications for second cancer induction. METHODS AND MATERIALS Dose was measured at increasing distances from the field edge in a water bath with a sloping wall (1) under full scatter conditions, (2) with the field edge abutting but outside the bath to prevent internal (water) scatter, and (3) with the beam aperture plugged to reflect leakage only. RESULTS Internal patient scatter from IMRT is 11% lower than 3DCRT, but collimator scatter and head leakage are five and three times higher, respectively. Ultimately, total scattered dose is 80% higher with IMRT; however this difference is small in absolute terms, being 0.14% of prescribed dose. Secondary dose from 3DCRT is mostly due to internal patient scatter, which contributes 70% of the total and predominates until 25 cm from the field edge. For IMRT, however, machine scatter/leakage is the dominant source, contributing 65% of the secondary dose. Internal scatter predominates for just the first 10 cm from field edge, collimator scatter for the next 10 cm, and head leakage thereafter. CONCLUSIONS Out-of-field dose is 80% higher with IMRT, but differences are tiny in absolute terms. Reductions in internal patient scatter with IMRT are outweighed by increased machine scatter and leakage, at least for small fields. Reductions from IMRT in dose to tissues within the portals and in internal scatter, which predominates close to the field edge, means that calculations based solely on dose to distant tissues may overestimate carcinogenic risks.
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Affiliation(s)
- Jeremy D Ruben
- William Buckland Radiotherapy Centre, The Alfred, Melbourne, Australia.
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93
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Wolff HA, Wagner DM, Christiansen H, Hess CF, Vorwerk H. Single fraction radiosurgery using Rapid Arc for treatment of intracranial targets. Radiat Oncol 2010; 5:77. [PMID: 20836871 PMCID: PMC2949676 DOI: 10.1186/1748-717x-5-77] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2010] [Accepted: 09/13/2010] [Indexed: 11/10/2022] Open
Abstract
Background Stereotactic-Radio-Surgery (SRS) using Conformal-Arc-Therapy (CAT) is a well established irradiation technique for treatment of intracranial targets. Although small safety margins are required because of very high accuracy of patient positioning and exact online localisation, there are still disadvantages like long treatment time, high number of monitor units (MU) and covering of noncircular targets. This planning study analysed whether Rapid Arc (RA) with stereotactic localisation for single-fraction SRS can solve these problems. Methods Ten consecutive patients were treated with Linac-based SRS. Eight patients had one or more brain metastases. The other patients presented a symptomatic vestibularis schwannoma and an atypic meningeoma. For all patients, two plans (CAT/RA) were calculated and analysed. Results Conformity was higher for RA with additional larger low-dose areas. Furthermore, RA reduced the number of MU and the treatment time for all patients. Dose to organs at risk were equal or slightly higher using RA in comparison to CAT. Conclusions RA provides a new alternative for single-fraction SRS irradiation combining advantages of short treatment time with lower number of MU and better conformity in addition to accuracy of stereotactic localisation in selected cases with uncomplicated clinical realization.
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Affiliation(s)
- Hendrik A Wolff
- Department of Radiotherapy and Radiooncology, Universitätsmedizin Göttingen, Germany.
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94
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A review of the clinical evidence for intensity-modulated radiotherapy. Clin Oncol (R Coll Radiol) 2010; 22:643-57. [PMID: 20673708 DOI: 10.1016/j.clon.2010.06.013] [Citation(s) in RCA: 171] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2009] [Revised: 03/03/2010] [Accepted: 06/23/2010] [Indexed: 02/07/2023]
Abstract
AIMS Intensity-modulated radiotherapy (IMRT) is a development of three-dimensional conformal radiotherapy that offers improvements in dosimetry in many clinical scenarios. Here we review the clinical evidence for IMRT and present ongoing or unpublished randomised controlled trials (RCTs). METHODS We identified randomised and non-randomised comparative studies of IMRT and conventional radiotherapy using MEDLINE, hand-searching Radiotherapy and Oncology and the International Journal of Radiation Oncology, Biology and Physics and the proceedings of the American Society for Therapeutic Radiology and Oncology and the European Society for Therapeutic Radiology and Oncology annual meetings. The metaRegister of Controlled Trials was searched to identify completed-unpublished, ongoing and planned RCTs. RESULTS Sixty-one studies comparing IMRT and conventional radiotherapy were identified. These included three RCTs in head and neck cancer (205 patients) and three in breast cancer (664 patients) that had reported clinical outcomes; these were all powered for toxicity-related end points, which were significantly better with IMRT in each trial. There were 27 additional non-randomised studies in head and neck (1119 patients), 26 in prostate cancer (>5000 patients), four in breast cancer (875 patients) and nine in other tumour sites. The results of these studies supported those of the RCTs with benefits reported in acute and late toxicity, health-related quality of life and tumour control end points. Twenty-eight completed-unpublished, ongoing or planned RCTs incorporating IMRT were identified, including at least 12,310 patients, of which 15 compared conventional radiotherapy within IMRT as a randomisation or pre-planned stratification. DISCUSSION Inverse-planned IMRT maintains parotid saliva production and reduces acute and late xerostomia during radiotherapy for locally advanced head and neck cancer, reduces late rectal toxicity in prostate cancer patients allowing safe dose escalation and seems to reduce toxicity in several other tumour sites. Forward-planned IMRT reduces acute toxicity and improves late clinician-assessed cosmesis compared with conventional tangential breast radiotherapy.
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95
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Gómez F, Iglesias A, Doblado FS. A new active method for the measurement of slow-neutron fluence in modern radiotherapy treatment rooms. Phys Med Biol 2010; 55:1025-39. [DOI: 10.1088/0031-9155/55/4/008] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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96
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Vautravers C, Dewas S, Truc G, Penel N. Sarcomes en territoire irradié : actualités. Cancer Radiother 2010; 14:74-80. [DOI: 10.1016/j.canrad.2009.09.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2008] [Revised: 07/08/2009] [Accepted: 09/11/2009] [Indexed: 11/16/2022]
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97
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Hermesse J, Biver S, Jansen N, Lenaerts E, De Patoul N, Vynckier S, Coucke P, Scalliet P, Nickers P. A Dosimetric Selectivity Intercomparison of HDR Brachytherapy, IMRT and Helical Tomotherapy in Prostate Cancer Radiotherapy. Strahlenther Onkol 2009; 185:736-42. [DOI: 10.1007/s00066-009-2009-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2009] [Accepted: 07/16/2009] [Indexed: 11/24/2022]
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98
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Oliver M, Ansbacher W, Beckham WA. Comparing planning time, delivery time and plan quality for IMRT, RapidArc and Tomotherapy. J Appl Clin Med Phys 2009; 10:117-131. [PMID: 19918236 PMCID: PMC5720582 DOI: 10.1120/jacmp.v10i4.3068] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2009] [Revised: 07/14/2009] [Accepted: 07/17/2009] [Indexed: 11/23/2022] Open
Abstract
The purpose of this study is to examine plan quality, treatment planning time, and estimated treatment delivery time for 5- and 9-field sliding window IMRT, single and dual arc RapidArc, and tomotherapy. For four phantoms, 5- and 9-field IMRT, single and dual arc RapidArc and tomotherapy plans were created. Plans were evaluated based on the ability to meet dose-volume constraints, dose homogeneity index, radiation conformity index, planning time, estimated delivery time, integral dose, and volume receiving more than 2 and 5 Gy. For all of the phantoms, tomotherapy was able to meet the most optimization criteria during planning (50% for P1, 67% for P2, 0% for P3, and 50% for P4). RapidArc met less of the optimization criteria (25% for P1, 17% for P2, 0% for P3, and 0% for P4), while IMRT was never able to meet any of the constraints. In addition, tomotherapy plans were able to produce the most homogeneous dose. Tomotherapy plans had longer planning time, longer estimated treatment times, lower conformity index, and higher integral dose. Tomotherapy plans can produce plans of higher quality and have the capability to conform dose distributions better than IMRT or RapidArc in the axial plane, but exhibit increased dose superior and inferior to the target volume. RapidArc, however, is capable of producing better plans than IMRT for the test cases examined in this study.
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Affiliation(s)
- Mike Oliver
- Department of Medical Physics, British Columbia Cancer Agency, Victoria, British Columbia, Canada
| | - Will Ansbacher
- Department of Medical Physics, British Columbia Cancer Agency, Victoria, British Columbia, Canada
| | - Wayne A Beckham
- Department of Medical Physics, British Columbia Cancer Agency, Victoria, British Columbia, Canada
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99
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Ares C, Khan S, Macartain AM, Heuberger J, Goitein G, Gruber G, Lutters G, Hug EB, Bodis S, Lomax AJ. Postoperative proton radiotherapy for localized and locoregional breast cancer: potential for clinically relevant improvements? Int J Radiat Oncol Biol Phys 2009; 76:685-97. [PMID: 19615828 DOI: 10.1016/j.ijrobp.2009.02.062] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2008] [Revised: 02/23/2009] [Accepted: 02/24/2009] [Indexed: 02/01/2023]
Abstract
PURPOSE To study the potential reduction of dose to organs at risk (OARs) with intensity-modulated proton radiotherapy (IMPT) compared with intensity-modulated radiotherapy (IMRT) and three-dimensional conformal radiotherapy (3D-CRT) photon radiotherapy for left-sided breast cancer patients. METHODS AND MATERIALS Comparative treatment-planning was performed using planning computed tomography scans of 20 left-sided breast cancer patients. For each patient, three increasingly complex locoregional volumes (planning target volumes [PTVs]) were defined: whole breast (WB) or chest wall (CW) = (PTV1), WB/CW plus medial-supraclavicular (MSC), lateral-supraclavicular (LSC), and level III axillary (AxIII) nodes = (PTV2) and WB/CW+MSC+LSC+AxIII plus internal mammary chain = (PTV3). For each patient, 3D-CRT, IMRT, and IMPT plans were optimized for PTV coverage. Dose to OARs was compared while maintaining target coverage. RESULTS All the techniques met the required PTV coverage except the 3D-CRT plans for PTV3-scenario. All 3D-CRT plans for PTV3 exceeded left-lung V20. IMPT vs. 3D-CRT: significant dose reductions were observed for all OARs using IMPT for all PTVs. IMPT vs. IMRT: For PTV2 and PTV3, low (V5) left lung and cardiac doses were reduced by a factor >2.5, and cardiac doses (V22.5) were by a factor of >20 lower with IMPT compared with IMRT. CONCLUSIONS When complex-target irradiation is needed, 3D-CRT often compromises the target coverage and increases the dose to OARs; IMRT can provide better results but will increase the integral dose. The benefit of IMPT is based on improved target coverage and reduction of low doses to OARs, potentially reducing the risk of late-toxicity. These results indicate a potential role of proton-radiotherapy for extended locoregional irradiation in left breast cancer.
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Affiliation(s)
- Carmen Ares
- Center for Proton Therapy, Paul Scherrer Institute, Villigen, Switzerland.
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100
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Toda K, Shibuya H, Hayashi K, Ayukawa F. Radiation-induced cancer after radiotherapy for non-Hodgkin's lymphoma of the head and neck: a retrospective study. Radiat Oncol 2009; 4:21. [PMID: 19591686 PMCID: PMC2717106 DOI: 10.1186/1748-717x-4-21] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2009] [Accepted: 07/10/2009] [Indexed: 12/01/2022] Open
Abstract
Background survivors of non-Hodgkin's lymphoma (NHL) are well known to be at an increased risk of second malignancies. In this study, we evaluated the incidence and clinical features of head and neck cancer (HNC) occurring after radiotherapy (RT) for NHL. Materials and methods We investigated the clinical records of 322 patients who had received RT for early-stage NHL of the head and neck at our institute between 1952 and 2000. Results There were 4 patients with a second HNC developing in the irradiated field, consisting of 2 patients with gum cancer, 1 case with tongue cancer and 1 case with maxillary sinus cancer. The pathological diagnosis in all the 4 patients was squamous cell carcinoma (SCC). Two of the patients (one with gum cancer and one with maxillary sinus cancer) died of the second HNC, while the remaining 2 patients are still living at the time of writing after therapy for the second HNC, with neither recurrence of the second tumor nor relapse of the primary tumor. The ratio of the observed to the expected number (O/E ratio) of a second HNC was calculated to be 12.7 (95%CI, 4.07–35.0), and the absolute excess risk (AER) per 10,000 person-years was 13.3. The median interval between the RT and the diagnosis of the second HNC was 17.0 years (range, 8.7 to 22.7 years). Conlusion The risk of HNC significantly increased after RT for early-stage NHL. These results suggest that second HNC can be regarded as one of the late complications of RT for NHL of the head and neck.
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Affiliation(s)
- Kazuma Toda
- Department of Radiology, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo, Japan.
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