5.257.
In accordance with para. 3.178 of GSR Part 3 [3], a radiation therapy facility is required to have arrangements in place to manage the release of patients who have permanent brachytherapy implants. Once the patient is released, two groups of persons should be afforded appropriate radiation protection: the general public whom the patient may encounter or with whom the patient may interact, and members of the patient’s family and close friends, who may be viewed simply as also being members of the public or as carers and comforters. Exposure of members of the public is subject to the public dose limits (see Box 1), while exposure of carers and comforters is not subject to dose limits but is instead controlled through dose constraints (see paras 2.46–2.49 and 5.248–5.252). Furthermore, as stated in para. 2.46, public exposure arising from a single ‘source’, such as the patient with the implants, should be subject to dose constraints set at some fraction of the dose limits.
5.258.
The medical physicist or RPO at the radiation therapy facility should establish prior to the release of a patient that the radioactivity of the implants is such that the doses that could be received by members of the public would not exceed the dose limits, and would be unlikely to exceed the relevant dose constraints for both members of the public and carers and comforters. An acceptable method of estimating the acceptable activity of permanent implants for patients being discharged from hospitals is to calculate the time integral of the ambient dose equivalent rate, considering the activity, energy and half-life of the radionuclides. In the case of carers and comforters, the assumptions made for the calculations should be consistent with the written instructions that will be given at the time the patient is discharged from the facility. Published data suggest that systematic dose monitoring, at least in the case of permanent brachytherapy implanted sources for the treatment of prostate cancer, is not necessary [340, 401].
5.259.
As indicated in para. 5.258, the patient or the legal guardian of the patient should be provided with written instructions on how to keep doses to members of the public and carers and comforters as low as reasonably achievable. Individuals of particular concern are children and pregnant partners of patients. The ICRP provides detailed guidance and a sample information sheet for implanted sources for prostate cancer in Ref. [401].
5.260.
There is a low probability of an implanted seed being expelled, for example with prostate treatment. The written instructions should cover this possibility and should provide guidance on what to do and what not to do. Detailed advice is provided by the ICRP [401].
5.261.
The patient with permanent brachytherapy implants should be informed that, if he or she is to undergo subsequent surgery, the surgeon should be informed of the presence of the implants; for example, a prostate cancer patient undergoing subsequent pelvic or abdominal surgery. A wallet card with all relevant information about the implant is useful [401] (see para. 5.289 on management of a deceased patient with permanent implants).
5.262.
Information should also be provided to the patient on radiation risks, including guidance with respect to fertility in the case of implants for prostate cancer [401].