Effect of a urinary catheter on seed position and rectal and bladder doses in CT-based post-implant dosimetry for prostate cancer brachytherapy

To assess the variability in rectal and bladder dosimetric parameters determined according to post-implant computed tomography (CT) images in patients with or without a urethral catheter.

Patients with prostate cancer who were scheduled to undergo CT after brachytherapy between October 2012 and January 2014 were included.

We obtained CT series with and without a urinary catheter in each patient. We compared the rectal and bladder doses in 18 patients on each CT series.

The shifts in the seed positions between with and without a catheter in place were 1. 3 ± 0. 3 mm (mean ± standard deviation). The radiation doses to the rectum, as determined on the CT series, with a urethral catheter were higher than those on CT without a catheter (p < 0. 001). Radiation doses to the bladder with a catheter were significantly lower than those without a catheter (p = 0. 027).

Post-implant dosimetry (PID) with no catheter showed significantly lower rectal doses and higher bladder doses than those of PID with a catheter. We recommend the PID procedure for CT images in patients without a catheter. Use of CT with a catheter is limited to identifying urethral position.

Journal of contemporary brachytherapy. 2015 Jun 29 [Epub]

Hiroaki Kunogi, Nanae Yamaguchi, Yoshiaki Wakumoto, Keisuke Sasai

Department of Radiation Oncology. , Department of Radiation Oncology. , Department of Urology, Juntendo University, Hongo, Bunkyo-ku, Tokyo, Japan. , Department of Radiation Oncology.

PubMed    Full Text Article


Newsletter subscription

Free Daily and Weekly newsletters offered by content of interest

The fields of GU Oncology and Urology are rapidly advancing. Sign up today for articles, videos, conference highlights and abstracts from peer-review publications by disease and condition delivered to your inbox and read on the go.