Summary
- Brachytherapy is an established form of radiotherapy involving implantation of a radioactive source at the site to be treated.
- A major disadvantage of brachytherapy is that it involves exposure of medical, technical and nursing staff to radiation during insertion and removal of the source, and care of the patient while the source is in place.
- To overcome this problem, automated afterloading systems have been developed. With these, sources are inserted under computer control in a shielded room, and automatically withdrawn into a lead safe when persons enter the room.
- Low dose rate treatment delivered by automated afterloading systems is equivalent to traditional brachytherapy and can be expected to have similar clinical efficacy.
- With automated systems, use of high dose rates with shortened treatment times is also possible. The clinical value of high dose rate treatment has not been fully established.
- The case for automated afterloading rests primarily on the reduction in radiation exposure of staff.
- Current levels of radiation exposure for brachytherapy staff, would result in around one cancer every hundred years. Genetic disorders would be induced at a comparable rate. The use of automated afterloading to avert occupational cancers would cost about $40 million per fatal cancer prevented.
- The use of automated afterloading is difficult to justify on economic grounds but other factors need to be taken into account, particularly the principle that occupational radiation doses should be as low as reasonably achievable, and the need to maintain staff confidence.
- Patients may also benefit from increased nursing care and contact with other persons, in comparison with manual treatment, but these benefits may be offset by the discomfort of being linked by a tube to the afterloading device throughout the treatment period (up to several days if low dose rates are used).
The Panel considers that:
- the use in Australia of automated afterloading systems is desirable for low dose rate brachytherapy in view of perceived occupational health benefits to medical, nursing and other staff;
- use of automated afterloading systems may also provide benefits through allowing high dose rate therapies and increased levels of ,nursing care, although these are less certain.