Breast radiotherapy: an Australasian survey of current treatment techniques.

Prior to the dissemination of evidence-based quality assurance guidelines, the Australian National Breast Cancer Centre Radiation Oncology Group conducted a process survey of breast radiotherapy treatment delivery throughout Australia. A process survey was conducted in August/September 1998. This survey comprised questions enquiring about treatment positioning, immobilization devices used, planning strategies, simulation and dose computation methods, treatment prescribing and quality assurance. The survey was sent to 123 Australian fellows of the Royal Australian and New Zealand College of Radiologists (RANZCR) and to the six directors of New Zealand radiation oncology departments. Fifty-eight questionnaires were returned of which 38 were received from individuals and 20 represented a reply from a department with a routine breast radiotherapy protocol (representing an average of 4.5 radiation oncologists per reply). The study identified great consistency between departments with respect to dose and fractionation for breast tangents. The study also identified some areas of treatment planning and delivery that varied between individuals or departments. These mainly reflected a lack of evidence in some areas of radiotherapy treatment delivery. The circulation of quality assurance guidelines will perhaps improve consistency of radiotherapy techniques in which studies have identified that technique changes improve outcome. This study identified that these areas include the taking of simulation and port films and the use of off-axis dosimetry. Further studies are required for areas of radiotherapy treatment delivery that have little evidence for or against their implementation.