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Accelerated tomotherapy delivery with TomoEdge technique

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      Abstract

      TomoEDGE is an advanced delivery form of tomotherapy which uses a dynamic secondary collimator. This plan comparison study describes the new features, their clinical applicability, and their effect on plan quality and treatment speed. For the first 45 patients worldwide that were scheduled for a treatment with TomoEdge, at least two plans were created: one with the previous “standard”mode with static jaws and 2.5 cm field width (Reg 2.5) and one with TomoEdge technique and 5 cm field width (Edge 5). If, after analysis in terms of beam on time, integral dose, dose conformity, and organ at risk sparing the treating physician decided that the Edge 5 plan was not suitable for clinical treatment, a plan with TomoEdge and 2.5 cm field width was created (Edge 2.5) and used for the treatment. Among the 45 cases, 30 were suitable for Edge 5 treatment, including treatments of the head and neck, rectal cancer, anal cancer, malignancies of the chest, breast cancer, and palliative treatments. In these cases, the use of a 5 cm field width reduced beam on time by more than 30% without compromising plan quality. The 5 cm beam could not be clinically applied to treatments of the pelvic lymph nodes for prostate cancer and to head and neck irradiations with extensive involvement of the skull, as dose to critical organs at risk such as bladder (average dose 28 Gy vs. 29 Gy, Reg 2.5 vs. Edge 5), small bowel (29% vs. 31%, Reg 2.5 vs. Edge 5) and brain (average dose partial brain 19 Gy vs. 21 Gy, Reg 2.5 vs. Edge 5) increased to a clinically relevant, yet not statistically significant, amount. TomoEdge is an advantageous extension of the tomotherapy technique that can speed up treatments and thus increase patient comfort and safety in the majority of clinical settings.

      PACS numbers: 87.55.de, 87.55ne

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      Most cited references 15

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      Tomotherapy: a new concept for the delivery of dynamic conformal radiotherapy.

      Tomotherapy, literally "slice therapy," is a proposal for the delivery of radiation therapy with intensity-modulated strips of radiation. The proposed method employs a linear accelerator, or another radiation-emitting device, which would be mounted on a ring gantry like a CT scanner. The patient would move through the bore of the gantry simultaneously with gantry rotation. The intensity modulation would be performed by temporally modulated multiple independent leaves that open and close across the slit opening. At any given time, any leaf would be (1) closed, covering a portion of the slit, (2) open, allowing radiation through, or (3) changing between these states. This method would result in the delivery of highly conformal radiation. Overall treatment times should be comparable with contemporary treatment delivery times. The ring gantry would make it convenient to mount a narrow multisegmented megavoltage detector system for beam verification and a CT scanner on the treatment unit. Such a treatment unit could become a powerful tool for treatment planning, conformal treatment, and verification using tomographic images. The physical properties of this treatment delivery are evaluated and the fundamental design specifications are justified.
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        RTOG GU Radiation oncology specialists reach consensus on pelvic lymph node volumes for high-risk prostate cancer.

        Radiation therapy to the pelvic lymph nodes in high-risk prostate cancer is required on several Radiation Therapy Oncology Group (RTOG) clinical trials. Based on a prior lymph node contouring project, we have shown significant disagreement in the definition of pelvic lymph node volumes among genitourinary radiation oncology specialists involved in developing and executing current RTOG trials. A consensus meeting was held on October 3, 2007, to reach agreement on pelvic lymph node volumes. Data were presented to address the lymph node drainage of the prostate. Extensive discussion ensued to develop clinical target volume (CTV) pelvic lymph node consensus. Consensus was obtained resulting in computed tomography image-based pelvic lymph node CTVs. Based on this consensus, the pelvic lymph node volumes to be irradiated include: distal common iliac, presacral lymph nodes (S(1)-S(3)), external iliac lymph nodes, internal iliac lymph nodes, and obturator lymph nodes. Lymph node CTVs include the vessels (artery and vein) and a 7-mm radial margin being careful to "carve out" bowel, bladder, bone, and muscle. Volumes begin at the L5/S1 interspace and end at the superior aspect of the pubic bone. Consensus on dose-volume histogram constraints for OARs was also attained. Consensus on pelvic lymph node CTVs for radiation therapy to address high-risk prostate cancer was attained and is available as web-based computed tomography images as well as a descriptive format through the RTOG. This will allow for uniformity in evaluating the benefit and risk of such treatment.
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          • Record: found
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          Comparison of intensity-modulated radiotherapy with conventional conformal radiotherapy for complex-shaped tumors.

           J Debus,  A Pirzkall,  A Höss (2000)
          Conformal and intensity-modulated radiotherapy (IMRT) plans for 9 patients were compared based on characterization of plan quality and effects on the oncology department. These clinical cases, treated originally with conformal radiotherapy (CRT), required extraordinary effort to produce conformal treatment plans using nonmodulated, shaped noncoplanar fields with multileaf collimators (MLCs). IMRT plans created for comparison included rotational treatments with slit collimator, and fixed-field MLC treatments using equispaced coplanar, and noncoplanar fields. Plans were compared based upon target coverage, target conformality, dose homogeneity, monitor units (MU), user-interactive planning time, and treatment delivery time. The results were subjected to a statistical analysis. IMRT increased target coverage an average of 36% and conformality by 10%. Where dose escalation was a goal, IMRT increased mean dose by 4-6 Gy and target coverage by 19% with the same degree of conformality. Rotational IMRT was slightly superior to fixed-field IMRT. All IMRT techniques increased integral dose and target dose heterogeneity. IMRT planning times were significantly less, whereas MU increased significantly; estimated delivery times were similar. IMRT techniques increase dose and target coverage while continuing to spare organs-at-risk, and can be delivered in a time frame comparable to other sophisticated techniques.
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            Author and article information

            Affiliations
            [ 1 ] Department of Radiation Oncology University Hospital Heidelberg Heidelberg
            [ 2 ] Heidelberg Institute for Radiation Oncology (HIRO) Heidelberg
            [ 3 ] Department of Radiation Oncology German Cancer Research Center Heidelberg Germany
            Author notes
            [* ] a Corresponding author: Sonja Katayama, Department of Radiation Oncology, University Hospital Heidelberg, Im Neuenheimer Feld 400, 69120 Heidelberg, Germany; phone: +49‐6221‐568202; fax: +49‐6221‐565353; email: sonja.katayama@ 123456med.uni-heidelberg.de

            Contributors
            sonja.katayama@med.uni-heidelberg.de
            Journal
            J Appl Clin Med Phys
            J Appl Clin Med Phys
            10.1002/(ISSN)1526-9914
            ACM2
            Journal of Applied Clinical Medical Physics
            John Wiley and Sons Inc. (Hoboken )
            1526-9914
            08 March 2015
            March 2015
            : 16
            : 2 ( doiID: 10.1002/acm2.2015.16.issue-2 )
            : 33-42
            26103170 5690089 10.1120/jacmp.v16i2.4964 ACM20033
            © 2015 The Authors.

            This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

            Counts
            Figures: 4, Tables: 3, References: 15, Pages: 10, Words: 4019
            Product
            Funding
            Funded by: Medical Faculty, University of Heidelberg
            Categories
            Radiation Oncology Physics
            Radiation Oncology Physics
            Custom metadata
            2.0
            acm20033
            March 2015
            Converter:WILEY_ML3GV2_TO_NLMPMC version:5.2.5 mode:remove_FC converted:16.11.2017

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