Australasian brachytherapy audit: Results of the 'end-to-end' dosimetry pilot study

• Published in: Journal of medical imaging and radiation oncology 2013-08, Vol.57 (4), p.490-498
• Main Authors: Haworth, Annette, Wilfert, Lisa, Butler, Duncan, Ebert, Martin A, Todd, Stephen, Bucci, Joseph, Duchesne, Gillian M, Joseph, David, Kron, Tomas
• Format: Article
• Language: English
• Subjects: 192Ir; Audits; Australasia; brachytherapy; Brachytherapy - standards; external audit; Feasibility Studies; HDR; Humans; Medical Audit; Medical technology; Medicine; Pilot Projects; Practice Guidelines as Topic; Radiation therapy; Radiometry - standards; Radiotherapy Dosage - standards; Reproducibility of Results; Sensitivity and Specificity
• ISSN: 1754-9477; 1754-9485
• DOI: 10.1111/1754-9485.12042

Introduction We present the results of a pilot study to test the feasibility of a brachytherapy dosimetry audit. Methods The feasibility study was conducted at seven sites from four Australian states in both public and private centres. A purpose‐built cylindrical water phantom was imaged using the local imaging protocol and a treatment plan was generated to deliver 1 Gy to the central (1 of 3) thermoluminescent dosimeter (TLD) from six dwell positions. Results All centres completed the audit, consisting of three consecutive irradiations, within a 2‐h time period, with the exception of one centre that uses a pulsed dose rate brachytherapy unit. All TLD results were within 4.5% of the predicted value, with the exception of one subset where the dwell position step size was incorrectly applied. Conclusions While the limited data collected in the study demonstrated considerable heterogeneity in clinical practice, the study proved a brachytherapy dosimetry audit to be feasible. Future studies should include verification of source strength using a Standard Dosimetry Laboratory calibrated chamber, a phantom that more closely mimics the clinical situation, a more comprehensive review of safety and quality assurance (QA) procedures including source dwell time and position accuracy, and a review of patient treatment QA procedures such as applicator position verification.