Brachytherapy, also called radioactive seed implant therapy, puts radiation right where the cancer is. Tiny radioactive seeds (about the size of a grain of rice) are implanted into the prostate, where the radiation kills the cancer cells. Because the seeds are so close to the cancer cells, the cancer cells get inundated with radiation while the rectum, bladder, penis and other surrounding tissues receive much less radiation.
Other radiation therapy techniques penetrate radiation from outside the body to the inside. The radiation must first go through normal tissue before it reaches the prostate located deep inside the body. With seed implant treatment, radiation hits the prostate first, and only then strikes normal tissues. While the implant technique has been around for decades, recent advances in imaging technology have made it more effective. Using ultrasound to see the prostate gland better, physicians can place each seed in the prostate more carefully and better control the effect on surrounding tissues. Long-term results are available for up to 10–12 years at some institutions. These results show that ultrasound-guided radioactive implantation by very experienced physicians is highly effective in controlling prostate cancer and has essentially the same result as surgery or external radiation for appropriately selected low-risk prostate cancer patients.
High Dose Rate (HDR) Brachytherapy - This technique was developed to supplement the dose of radiation given as external beam therapy for patients with high risk prostate cancer. In highly skilled hands, this is an effective regimen to treat such cancers. Patients receive several weeks of standard external beam radiation therapy, followed by one to three HDR sessions. These sessions require anesthesia and placement of several needles into the prostate. The patient is then hooked up to the HDR machine, where a radioactive source moves up and down each needle, delivering radiation. This type of brachytherapy leaves no permanent radiation in the patient.
How can I choose from among the options?
In addition to talking with family and friends, you will need a team of physicians to help advise you. By the time of diagnosis, you will already have met two of the three or four doctors you will need for your cancer treatment planning: your primary care physician (an internist or family practice doctor) and a urologist, who probably performed the biopsy. (In some cases, a radiologist performs the biopsy.) If you have an early-stage cancer or moderately advanced cancer and there is no evidence of spread to other organs (non-metastatic), you need to talk to one more doctor: a radiation oncologist. The two major options for treatment are surgery (performed by your urologist) and radiation therapy (performed by a radiation oncologist).
How effective is modern radiation treatment of prostate cancer?
With modern technology, radiation therapy can:
- give more radiation dose directly to the prostate than to surrounding healthy tissues
- help physicians use x-rays to see the prostate and surrounding tissues in three dimensions, so that the radiation beams can be tailored more precisely to the individual patient's unique needs
- estimate what dose of radiation the nearby rectum, bladder, hips and penis will receive during the course of x-ray treatments to the prostate
- safely provide a higher dose of radiation than even five years ago, which helps to improve the chances of cure.