[Improvement of interstitial brachytherapy for localized prostate neoplasms with a new implantation technique]

The success of an interstitial brachytherapy treatment is based on the correct implantation geometry. Frequently, deviations of top needle vs. template coordinates were observed by transrectal sonography of 358 high-dose-rate (HDR) implantations for prostate cancer.

In cooperation with the companies BIP GmbH and Isotopen-Technik Dr. Sauerwein GmbH we developed a high-speed implantation machine, which was tested by 22 interstitial prostate applications. We compared the manual needle positioning method to the high-speed machine and observed the sequence of needle deviation as well as the acute postoperative side effects (hematoma, macroscopic hematuria, pain and urin stop).

Using the manual implantation method (n = 12) 43.8% of all implanted needles (42 out of 96, mean 3.5) showed a deviation vs. 3.6% (3 out of 83, mean 0.3) by the use of the high-speed device (n = 10). Acute postoperative side effects according to the implantation were: urin stop (3 vs. 0), macroscopic hematuria (3 vs. 1), and pain (4 vs. 1), respectively.

The use of a modified high-speed biopsy device for the interstitial brachytherapy results in a higher accuracy in the needle positioning and in reproducing pretreatment implantation plans. Because of the good clinical experience we introduced the high-speed implantation device into our clinical routine.