• Login
    View Item 
    •   Home
    • The Manchester Institute Cancer Research UK
    • All Paterson Institute for Cancer Research
    • View Item
    •   Home
    • The Manchester Institute Cancer Research UK
    • All Paterson Institute for Cancer Research
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

    All of ChristieCommunitiesTitleAuthorsIssue DateSubmit DateSubjectsThis CollectionTitleAuthorsIssue DateSubmit DateSubjects

    My Account

    LoginRegister

    Local Links

    The Christie WebsiteChristie Library and Knowledge Service

    Statistics

    Display statistics

    The influence of the number of fractions and bi-exponential repair kinetics on biological equivalence in pulsed brachytherapy.

    • CSV
    • RefMan
    • EndNote
    • BibTex
    • RefWorks
    Authors
    Millar, W T
    Hendry, Jolyon H
    Canney, Peter A
    Affiliation
    CRC Beatson Laboratories, Department of Radiation Oncology, University of Glasgow, UK.
    Issue Date
    1996-05
    
    Metadata
    Show full item record
    Abstract
    A linear-quadratic radiobiological model incorporating single or bi-exponential repair kinetics has been used to show the following and other features when a continuous low dose rate (CLDR) 70 Gy/140 h brachytherapy protocol is replaced by a radiobiologically equivalent pulsed dose rate (PDR) system using 140 fractions for reasons of dosage homogeneity. (1) For equivalent effects in late-reacting tissues, the PDR dose (at 5 or 0.05 Gy min-1) x 1 h intervals needs to be reduced by up to only 3%. Progressively further reductions in dose are required when fewer larger fractions are used. (2) When equivalence using pulsed doses is achieved for one normal tissue type, and extrapolated response doses (ERD) are calculated for other tissue types in the irradiated volume, values of the ERD remain within 5% of each other using the above PDR protocol and associated parameters. (3) For tumours with alpha/beta = 10 Gy and a single repair halftime of 0.1-1.0 h, there is no significant loss of therapeutic benefit using the PDR protocol equivalenced for late normal tissue reactions. The strategy of replacing an LDR boost protocol of about 24 Gy by a PDR protocol gives similar levels to the 70 Gy PDR protocol for the expected percentage increase in the biological dose to normal tissues (due to the PDR protocol alone). These calculations also highlight the importance of the values assumed for the conventional alpha/beta ratio and the repair kinetics when estimating equivalent PDR protocols. The use of an inappropriate radiobiological parameterization will lead to erroneous conclusions with the potential to advocate PDR protocols which will, in practice, lead to an increase in late complications.
    Citation
    The influence of the number of fractions and bi-exponential repair kinetics on biological equivalence in pulsed brachytherapy. 1996, 69 (821):457-68 Br J Radiol
    Journal
    The British Journal of Radiology
    URI
    http://hdl.handle.net/10541/95611
    PubMed ID
    8705185
    Type
    Article
    Language
    en
    ISSN
    0007-1285
    Collections
    All Paterson Institute for Cancer Research

    entitlement

    Related articles

    • Clinical implications of incomplete repair parameters for rat spinal cord: the feasibility of large doses per fraction in PDR and HDR brachytherapy.
    • Authors: Pop LA, Millar WT, Visser AG, van der Kogel AJ
    • Issue date: 2001 Sep 1
    • Biological effect of pulsed dose rate brachytherapy with stepping sources if short half-times of repair are present in tissues.
    • Authors: Fowler JF, Van Limbergen EF
    • Issue date: 1997 Mar 1
    • Biphasic and monophasic repair: comparative implications for biologically equivalent dose calculations in pulsed dose rate brachytherapy of cervical carcinoma.
    • Authors: Millar WT, Hendry JH, Davidson SE
    • Issue date: 2013 Sep
    • Is pulsed dose rate more damaging to spinal cord of rats than continuous low dose rate?
    • Authors: Haustermans K, Fowler J, Landuyt W, Lambin P, van der Kogel A, van der Schueren E
    • Issue date: 1997 Oct
    • Pulsed-dose-rate brachytherapy: design of convenient (daytime-only) schedules.
    • Authors: Brenner DJ, Schiff PB, Huang Y, Hall EJ
    • Issue date: 1997 Nov 1
    DSpace software (copyright © 2002 - 2023)  DuraSpace
    Quick Guide | Contact Us
    Open Repository is a service operated by 
    Atmire NV
     

    Export search results

    The export option will allow you to export the current search results of the entered query to a file. Different formats are available for download. To export the items, click on the button corresponding with the preferred download format.

    By default, clicking on the export buttons will result in a download of the allowed maximum amount of items.

    To select a subset of the search results, click "Selective Export" button and make a selection of the items you want to export. The amount of items that can be exported at once is similarly restricted as the full export.

    After making a selection, click one of the export format buttons. The amount of items that will be exported is indicated in the bubble next to export format.