Prostate cancer is the model cancer for brachytherapy. The prostate gland
is located under the bladder and in front of the rectum. It is vital that
radiation therapy be focused in the prostate to avoid significant side
effects. The prostate gland is also close enough to the skin that it can
be easily reached to place the permanent seed implants.
Approximately 100 radioactive seeds are injected into the prostate gland.
They give off their radiation at a low dose rate over several weeks or
months, and then the seeds remain in the prostate gland permanently.
What Does HDR Treatment for Prostate Cancer Involve?
This treatment frequently consists of a combination of two separate therapies:
- Moderate doses of External Beam Radiotherapy
- Low Dose Rate Prostate Seed Brachytherapy
External beam radiation is often included because cancer cells may migrate
outside the prostate gland, known as extra-prostatic extension. Treatments
like a radical prostatectomy and permanent seed implant alone may miss
cancer cells which have escaped outside the prostate into the surrounding tissues.
Scans like CT, MRI, ultrasound, and Prostascint may not detect cancer cells
that have spread outside the prostate. Even though these scans may not
show cancer spread beyond the prostate capsule, it can still be present.
External beam radiation helps to target those areas surrounding the prostate gland.
The procedure usually takes between one and three hours on an outpatient
basis, with patients typically returning to their normal activities within
a day or two.