The following is a summary of the key literature to date.
One randomized controlled trial (RCT) that evaluates the Spanner (Sp) prostatic stent has been published. Findings were published in 2008 by Dineen and colleagues. (1) The study evaluated the impact of the Spanner stent on management of voiding symptoms, irritative symptoms, and bother after transurethral microwave thermotherapy (TUMT). (1) Patients (n=186) were randomly assigned to the Sp (n=100) or standard of care (SOC, n=86) after TUMT and 3 to 10 days of routine catheterization. After catheter removal, the SOC group received no further treatment until follow-up visits. Primary outcomes evaluated included the International Prostate Symptom Score (IPSS) voiding subscore, IPSS irritative subscore, voiding diary data, and Benign Prostatic Hyperplasia Impact Index 7 to 10 days before TUMT and repeated 1, 2, 4 (stent removal), 5, and 8 weeks after stent insertion. The IPSS voiding and irritative subscores showed statistically significant improvement at week 1 for the Sp group but no significant differences at weeks 2, 4, 5, and 8. For the individual IPSS voiding and irritative questions of incomplete emptying, there were no significant differences between the Sp and SOC groups at any visit. Overall, individual IPSS irritative questions did not differ significantly between the Sp and SOC groups at 1, 2, and 4 weeks after stent insertion. From the voiding diary data, the feeling of incomplete emptying, terminal dribble, and leakage were not significantly different between the Sp and SOC groups at any visit. On the Benign Prostatic Hyperplasia Impact Index, the Sp group was less bothered during the time of stent use (2 weeks). The remaining weeks for this index were similar in both groups. While this study showed statistically significant changes in some outcome measures, the study has a number of limitations. First, participants or practitioners were not blinded to the treatment, so potential biases could have occurred on reporting the outcome measures. Second, no information is given about dropout rates or missing data. Finally, the clinical significance of many of the findings is not known. Thus, these data are inconclusive regarding the role of temporary prostatic stents for prostatic obstruction conditions.
Another report on the Spanner stent, published in 2007, described repeated temporary stent use in 43 consecutive patients with bladder-outlet obstruction who were unfit for surgery. (2) It was reported that more than half of the patients (63%) had unsatisfactory outcomes; the remaining 37% were considered to have had satisfactory outcomes, either with a stent in situ after a mean of 5 changes or stent-free after a successful voiding trial.
In 2006, Kijvikai and colleagues conducted a study in Europe to assess the efficacy and safety of 2 versions of a blind placement temporary prostatic stent (BPS-1 and BPS-2) in the treatment of patients with benign prostatic obstruction. (3) A total of 55 men were enrolled in the trial. Spontaneous voiding was achieved in all patients immediately after stent insertion, with improvements in voiding parameters and symptom scores. In patients with the BPS-1, migration occurred in 85%. In patients with the BPS-2, migration occurred in 5%. The median indwelling time of the stent was 16 days for the BPS-1 and 38 days for the BPS-2. Removal was successful in all but 1 case (BPS-2). The authors concluded that the BPS-1 and BPS-2 are not suitable for clinical practice because of the significantly high migration rate (BPS-1) and voiding parameters and symptom scores (BPS-2) that were not significantly improved. Given the study location and lack of FDA approval for these devices, these data are insufficient to draw conclusions regarding the use of these devices.
In 2005 and 2006, van Dijk and colleagues conducted studies for 2 designs (hourglass-shaped and bell-shaped) of removable stents in a total of 143 subjects. (4, 5) Unsatisfactory outcomes were reported for both models; the stents required early removal due to migration and other sources of pain, with a median retention of less than 105 days.
In 2008, Vanderbrink and colleagues published a review of the use of the temporary prostatic stent. (6) The report concluded that “….a major disadvantage of temporary prostatic stents is that they have a small lumen that can result in urinary retention secondary to clot–induced impairment of catheter patency, when placed in the immediate post-TUMT treatment.”
Data are inconclusive regarding the role of temporary prostatic stents for prostatic obstructive conditions. This procedure has not been shown to improve the net health outcome.
Practice Guidelines and Position Statements
Although previous versions of the American Urological Association guideline on the management of benign prostatic hyperplasia included a statement on temporary prostatic stents, this technology was not mentioned in the current version of the guideline (revised 2010). No other relevant practice guidelines or position statements were identified.
Disclaimer for coding information on Medical Policies
Procedure and diagnosis codes on Medical Policy documents are included only as a general reference tool for each policy. They may not be all-inclusive.
The presence or absence of procedure, service, supply, device or diagnosis codes in a Medical Policy document has no relevance for determination of benefit coverage for members or reimbursement for providers. Only the written coverage position in a medical policy should be used for such determinations.
Benefit coverage determinations based on written Medical Policy coverage positions must include review of the member’s benefit contract or Summary Plan Description (SPD) for defined coverage vs. non-coverage, benefit exclusions, and benefit limitations such as dollar or duration caps.