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Services & Therapies
Ultrasound-Guided Transperineal Prostate Brachytherapy "Seed" Implant Program

Radioactive “Seeds” are becoming the treatment of choice for early stage low risk prostate tumors. Clinical outcomes in these procedures are good (high rate of tumor control), and the rate of serious complications is much lower than is the case for a radical surgery. The name Transperineal Prostate Implant describes a technique in which a fairly large number of radioactive seeds (125I or 103Pd) are permanently implanted into the prostate gland under the real-time biplanar transrectal ultrasound. Seeds are delivered through a set of thin hollow needles. A needle, pre-loaded with linked radioactive seeds and spacers are inserted into the prostate gland and then gradually withdrawn, leaving behind a pattern of seeds. Needles are guided by a device called a template. The objective of this procedure is to deliver a reasonably uniform dose distribution to the prostate gland. Large doses of the order of 110 – 145 Gy, are generally delivered. This approach offers delivering a high dose of radiation to a confined volume relatively sparing of bladder and rectum. The treatment planning of this procedure consists of “pre-planning” and “post-planning” of dose distribution.

Procedure Overview
At Loyola we have used a team approach since the program started in January 1997. Our team includes Dr. Richard Garza from the Department of Radiation Oncology and several Urologist from Loyola’s Department of Urology as well as medical physics staff. Together we determine in advance the radiation dosage and number of seeds required, as well as the exact location in the prostate where the seeds need to be placed.

This program involves specialized equipment and technical expertise. At our disposal are radioactive seeds (either iodine or palladium), an ultrasound rectal probe to view and ensure the exact placement of each seed, the Bard SourceLink® Delivery System through which the seeds are inserted into the prostate, and a mapping template that serves as a guide for needle placement and seed delivery to the exact site where each seed must be positioned.

Before The Procedure
Before seeds are inserted they have to be customized for the patient based on his prostate size. We start the customizing process with a Volume Study. During a Volume Study we us a transrectal ultrasound to create a map of the prostate. For this map we are able to determine the exact size and shape of the prostate. After the Volume study the patient goes home and relaxes while over the next few weeks a team of dosimetrist and physicist reconstruct the prostate in 3D, determines the exact number of seeds and needles and radioactive strength needed to treat the prostate cancer. The patient returns in approximately 4 weeks for the seed insertion day.

Day of the Seed Implant
We perform the seed implant as an outpatient procedure. The procedure itself generally takes less than 2 hours but the patient should prepare to be at the Loyola Ambulatory Surgery Center most of the day. Patients are under anthestia and asleep for the entire procedure. We use an ultrasound probe inside the rectum to monitor each seed placement. The hollow needles that deliver the seeds are inserted through the perineum (skin between the scrotum and rectum). The typical number of seeds is between 85-125, and the typical number of hollow needles is between 20-35.

After The Procedure
Once the seeds are planted the patient is sent back to the recovery area for the anesthesia to wear off. If the patient can urinate the he is sent home without a urinary catheters. If the patient has difficulty urinating then the catheter is left in place for a few days. Before the patient leaves the hospital, he will be given specific radiation safety instructions. The seeds are permanent and designed to stay in side the patient for the rest of his life. The patient will be given an appointment to return to the Radiation Oncology department in 30 days for a scan to determine the final resting spot of the seeds.