Overcoming pubic arch interference with free-hand needle placement in men undergoing prostate brachytherapy

Abstract

Purpose The present study evaluates the postimplant dosimetry when free-hand needles were placed to overcome interference from the pubic arch. Methods and Materials A review of all patients who underwent prostate brachytherapy at our institution from 2001 to 2006 was performed. Postimplant dosimetry in men requiring free-hand needle placement was compared with postimplant dosimetry in men not requiring free-hand needle placement. Results Of the 145 patients who underwent prostate brachytherapy, 8 patients required free-hand needle placement. The mean prostate volume in the free-hand needle cohort was 46.0 cc with a mean of 3.4 free-hand needles placed. In the 137 patients not requiring free-hand needle placement, the mean volume was 39.7 cc. The mean D 90, V 100, V 150, and rectal V 100 for the free-hand cohort was 129.5%, 96.3%, 81.6%, and 1.45 cc, respectively. The mean D 90, V 100, V 150, and rectal V 100 in men not requiring free-hand needle placement was 126.8%, 97.1%, 78.7%, and 1.03 cc, respectively. Conclusion The present study finds that adequate postimplant dosimetry can be obtained if free-hand needles are required due to pubic arch interference.