Prophylactic Urethral Stenting With Memokath After Prostate Implantation for Prostate Adenocarcinoma
Prophylactic Urethral Stenting With Memokath After Prostate Implantation for Prostate Adenocarcinoma
The purpose of this study is to determine the feasibility, safety, and efficacy of the
 Memokath® 028SW stent to prevent urinary obstructive symptoms (difficulty urinating) when
 used after prostate seed implantation for the treatment of localized prostate cancer.
Image-guided transperineal permanent prostate brachytherapy (PI) is an accepted curative
 treatment option for patients with early stage prostate cancer. Multiple reports have defined
 its efficacy and shown it to be superior to antecedent trans-abdominal techniques. In
 addition, the efficacy of PI has been shown to be similar to radical retropubic prostatectomy
 (RRP) and external beam radiotherapy (EBRT). These positive results, however, are gained at
 the expense of toxicity. The most notable toxicity is associated with the urinary system. The
 most severe side effect of PI is urinary retention requiring intermittent
 self-catheterization (ISC).

 The reported rate of severe urinary retention following PI is ~10%. Most of these patients
 can be managed with ISC and alpha-blockers for a few weeks. Although this is generally a
 temporary phenomenon, a small percentage will eventually require surgical intervention to
 permit urinary flow. This is a major concern for patients undergoing PI, but should not be a
 reason to avoid this form of curative treatment.

 The use of implantable stents has been successful in BPH. The Memokath® device has been shown
 to decrease the International Prostate Symptom Score from a mean of 20.3 to 8.2 in the first
 3 months after stent placement in patients with bladder outlet obstruction unable to undergo
 TURP. Few experience side-effects with pain in 3%, hematuria in 3%, incontinence in 6%, and
 infection in 6%. A multicenter randomized control trial is currently underway assessing the
 use of this device in patients with recurrent urethral strictures.

 Urethral stents have been used with some success in patients with post-brachytherapy bladder
 outlet obstruction. Five patients, who could not tolerate alpha-blockers or clean
 intermittent catheterization, received UroLume urethral stents following one or more episodes
 of urinary retention. All patients were able to void immediately after stent placement. No
 patients developed incontinence after the stent placement. The main complaints following
 UroLume® stent placement were urethral bleeding, referred pain at the head of the penis, and
 dysuria. These symptoms required stent removal in 2 out of the 5 patients. In another study,
 five patients received SpannerTM urethral stents following significant urinary symptoms after
 prostate brachytherapy. All patients were able to void spontaneously with no post-void
 residual volume of urine. Flow rates increased and the International Prostate Symptom Score
 decreased from a mean of 25.2 to 10 (p=0.03). However, two patients experienced pain, which
 required removal of the stent.

 Given that few patients have experienced side effects with the Memokath® urethral stent in
 bladder outlet obstruction, we wish to assess the toxicity associated with this stent in a
 post-brachytherapy setting. In addition, we would like to assess its efficacy when used
 prophylactically in reducing bladder outlet obstruction following prostate brachytherapy and
 its impact on the AUA score.
Inclusion Criteria:

 -  eligible for prostate seed implant

 -  50 years of age or older

 -  able to give informed consent

 Exclusion Criteria:

 -  presence of any other urologic implant, including stents,penile prosthesis or
 artificial sphincter

 -  history of transurethral resection of prostate (TURP)procedure

 -  presence of urethral diverticuli

 -  presence of urethral strictures

 -  presence of bladder calculi or tumors

 -  prostatic urethra is less than 2.5 cm or greater than 6.5 cm

 -  inability to participate in study activities due to physical or mental limitations

 -  inability or unwillingness to return for all the required follow-up visits