Following the success of Iodine-125 implants for the treatment of early stage prostate cancer several centres have begun using remote afterloading techniques to treat more advanced T3 cancers. Afterloading offers you the possibility of optimising the implant, increasing the dose homogeneity within the implant, and treating disease that has spread to regions just outside the prostate. The brachytherapy treatment is used as a boost to compliment the external beam treatment that is used to treat the whole pelvic region.

The initial work on this has been done using high dose-rate afterloaders. With this technique the treatment is given in 2-4 large dose fractions (5-10 Gy) over a period of a few days to a few weeks. The fraction regimes that take place over a few weeks require a separate implant for each fraction, with the treatment being done on an outpatient basis.

At Cookridge hospital we are anticipating using our Pulsed Dose-Rate afterloader. This machine delivers a short pulse of irradiation for approximately fifteen minutes every hour and effectively mimics the low dose rate treatment given using Iridium-192 wires.

The physics department involvement in this development is to design and build a template that positions needles relative to the grid superimposed on the ultrasound volume study and holds the needles in place during the treatment. The template design was a combination of two other template designs and the template was made by the engineers at Cookridge hospital