HDR vs Permanent Seeds

Top Ten Reasons Why We Prefer HDR at CTCA

1. HDR is versatile. We have used it for tiny glands (10cc), big glands (100cc +), following a TURP, and even for treating recurrences after seeds.
2. HDR is in my opinion the most precise way to give radiation to the prostate: more conformal than seeds, protons, IMRT, or 3D EBRT.
3. HDR catheters can be easily placed in the extracapsular tissues and seminal vesicles. This allows HDR to treat stage 3 prostate cancer.
4. Once the HDR catheters are placed, the computer can control the amount of radiation given to each catheter, correcting for catheters that are too close together, too far apart, or too close to the urethra or rectum. This helps prevent radiation hot spots and cold spots, which may occur with permanent seed implants if the seeds are injected too close together or too far apart.
5. The HDR dose can be "sculpted" in the prostate, boosting the dose to the tumor if its location is known, and giving less to the urine passage (urethra) and rectum. By adjusting the radiation dose in each catheter we can put the radiation where we need it.
6. Permanent seeds are irreversible. Once a permanent seed is placed, it cannot be moved, removed, or adjusted in any way, short of doing surgery. HDR catheters can be turned off, advanced, retracted, removed, or added. An HDR implant may even be aborted after the catheters have been placed.
7. Permanent seeds must be ordered in advance, which may cause delays and cost thousands of dollars for each patient.
8. Permanent seeds can migrate through the bloodstream to the lung, or can be urinated out.
9. There are usually restrictions placed on small children or pregnant women coming close to you for a time period after having a permanent seed implant because of the radioactivity being released by the seeds. With HDR, no radioactivity is left in you following the treatments.
10. Recent studies theorize that prostate cancer cells may respond better to the large fraction sizes of HDR, versus the slow release of radiation from permanent seeds.

There are some positive aspects about permanent seeds:

1. Seeds (in their modern method) have been used for about 5 years longer than modern HDR prostate brachytherapy and many more centers perform seed implants, so longer follow-up information is available.
2. Seeds do not require you to be admitted to hospital for 24 hours.
3. Seeds are very often used without external beam radiation. HDR, on the other hand, is usually combined with 4 - 5 weeks of external beam.
4. A seed implant is cheaper than HDR + external beam.
5. A seed implant can therefore be a convenient and cost-effective one-day treatment for early stage cancers.
6. Seed implants are more widely available.
7. The published results for seeds are generally very good for early stage cancers, with implants done in major institutions with a lot of experience. (However, several hundred cancer centers are now doing seed implants with variable quality.)
8. An excellent seed implant will be similar to an HDR implant in terms of conformality (how well the prescribed radiation dose matches the prostate).

In the end, you need to do your own analysis in terms of the theoretical differences, potential cure rates, side effects, cost, time away from work, and location of treatment centers, to decide what treatment is right for you.