BACKGROUND AND PURPOSE: PARSPORT was a multi-centre randomised trial in the UK which compared Intensity-Modulated Radiotherapy (IMRT) and conventional radiotherapy (CRT) for patients with head and neck cancer. The dosimetry audit goals were to verify the plan delivery in participating centres, ascertain what tolerances were suitable for head and neck IMRT trials and develop an IMRT credentialing program. MATERIALS AND METHODS: Centres enrolling patients underwent rigorous quality assurance before joining the trial. Following this each centre was visited for a dosimetry audit, which consisted of treatment planning system tests, fluence verification films, combined field films and dose point measurements. RESULTS: Mean dose point measurements were made at six centres. For the primary planning target volume (PTV) the differences with the planned values for the IMRT and CRT arms were -0.6% (1.8% to -2.4%) and 0.7% (2.0% to -0.9%), respectively. Ninety-four percent of the IMRT fluence films for individual fields passed gamma criterion of 3%/3mm and 75% of the films for combined fields passed gamma criterion 4%/3mm (no significant difference between dynamic delivery and step and shoot delivery). CONCLUSIONS: This audit suggests that a 3% tolerance could be applied for PTV point doses. For dose distributions tolerances of 3%/3mm on individual fields and 4%/3mm for combined fields are proposed for multi-centre head and neck IMRT trials.
RCT Entities:
BACKGROUND AND PURPOSE: PARSPORT was a multi-centre randomised trial in the UK which compared Intensity-Modulated Radiotherapy (IMRT) and conventional radiotherapy (CRT) for patients with head and neck cancer. The dosimetry audit goals were to verify the plan delivery in participating centres, ascertain what tolerances were suitable for head and neck IMRT trials and develop an IMRT credentialing program. MATERIALS AND METHODS: Centres enrolling patients underwent rigorous quality assurance before joining the trial. Following this each centre was visited for a dosimetry audit, which consisted of treatment planning system tests, fluence verification films, combined field films and dose point measurements. RESULTS: Mean dose point measurements were made at six centres. For the primary planning target volume (PTV) the differences with the planned values for the IMRT and CRT arms were -0.6% (1.8% to -2.4%) and 0.7% (2.0% to -0.9%), respectively. Ninety-four percent of the IMRT fluence films for individual fields passed gamma criterion of 3%/3mm and 75% of the films for combined fields passed gamma criterion 4%/3mm (no significant difference between dynamic delivery and step and shoot delivery). CONCLUSIONS: This audit suggests that a 3% tolerance could be applied for PTV point doses. For dose distributions tolerances of 3%/3mm on individual fields and 4%/3mm for combined fields are proposed for multi-centre head and neck IMRT trials.
Authors: Christopher M Nutting; James P Morden; Kevin J Harrington; Teresa Guerrero Urbano; Shreerang A Bhide; Catharine Clark; Elizabeth A Miles; Aisha B Miah; Kate Newbold; MaryAnne Tanay; Fawzi Adab; Sarah J Jefferies; Christopher Scrase; Beng K Yap; Roger P A'Hern; Mark A Sydenham; Marie Emson; Emma Hall Journal: Lancet Oncol Date: 2011-01-12 Impact factor: 41.316
Authors: Christos Melidis; Walter R Bosch; Joanna Izewska; Elena Fidarova; Eduardo Zubizarreta; Satoshi Ishikura; David Followill; James Galvin; Ying Xiao; Martin A Ebert; Tomas Kron; Catharine H Clark; Elizabeth A Miles; Edwin G A Aird; Damien C Weber; Kenneth Ulin; Dirk Verellen; Coen W Hurkmans Journal: Radiother Oncol Date: 2014-05-08 Impact factor: 6.280
Authors: Catharine H Clark; Edwin G A Aird; Steve Bolton; Elizabeth A Miles; Andrew Nisbet; Julia A D Snaith; Russell A S Thomas; Karen Venables; David I Thwaites Journal: Br J Radiol Date: 2015-09-02 Impact factor: 3.039