Seattle Prostate Institute

About Seed Implantation -

The seeds used for prostate implants emit low energy radiation. This means that the radiation can travel only a very short distance before being absorbed by tissue. With the correct placement of the seeds, therefore, a very high dose of radiation can be given throughout the prostate gland with little exposure to the normal tissue and organs surrounding the prostate. Research has shown that higher doses of radiation result in higher rates of cure.

External beam radiation, by comparison, cannot achieve the same dose levels as seeds can. With this form of treatment, the dose must be lowered in order to avoid severe damage to the bladder, bowel, and other tissue through which the radiation beam must pass before reaching the prostate.

WHAT IS THE HISTORY OF SEED IMPLANTS

The idea of placing radioactive material into the prostate for the treatment of cancer has been around since the early 1900‘s. Modern prostate brachytherapy, however, began to take hold in the 1970’s when physicians at New York’s Sloan Kettering Memorial Cancer Center first began inserting radioactive seeds into the prostate using an open surgical procedure. With this technique, an incision was made in the abdomen to expose the prostate gland. Using only their hands to guide the surgical needles containing the seeds, the physicians inserted the seeds one by one into the prostate gland. (Figure 3)

Without the ability to see inside the prostate, physicians could not ensure that the seeds were being placed evenly throughout the gland The result was that some areas of the prostate would receive clumps of seeds (hot spots) while other areas would receive few or none (cold spots) as illustrated in (Figure 4). Predictably, these early procedures did not prove very successful in curing prostate cancer. Consequently, the open surgical technique fell into disrepute and was largely abandoned.

In the early 1980s, Dr. Hans Holm of Denmark began applying the new technology of transrectal ultrasound to seed implantation. Along with advances in computerized imaging software, ultrasound technology was a major step forward in the development of prostate brachytherapy.