Transurethral Waterjet Ablation of the Prostate

This LCD supplements but does not replace, modify, or supersede existing Medicare applicable National Coverage Determinations (NCDs) or payment policy rules and regulations for transurethral waterjet ablation of the prostate. Federal statute and subsequent Medicare regulations regarding provision and payment for medical services are lengthy. They are not repeated in this LCD. Neither Medicare payment policy rules nor this LCD replace, modify or supersede applicable state statutes regarding medical practice or other health practice professions acts, definitions and/or scopes of practice. All providers who report services for Medicare payment must fully understand and follow all existing laws, regulations and rules for Medicare payment for transurethral waterjet ablation of the prostate and must properly submit only valid claims for them. Please review and understand them and apply the medical necessity provisions in the policy within the context of the manual rules. Relevant CMS manual instructions and policies may be found in the following Internet-Only Manuals (IOMs) published on the CMS Web site:

IOM Citations:

• CMS IOM Publication 100-08, Medicare Program Integrity Manual,
  • Chapter 13, Section 13.5.4 Reasonable and Necessary Provision in an LCD
• CMS IOM Publication 100-02, Medicare Benefit Policy Manual,
  • Chapter 14, Section 10 Coverage of Medical Devices
• CMS IOM Publication 100-04, Medicare Claims Processing Manual,
  • Chapter 23, Section 30 Services paid under the Medicare Physicians Fee Schedule

Social Security Act (Title XVIII) Standard References:

• Title XVIII of the Social Security Act, Section 1862(a)(1)(A) states that no Medicare payment shall be made for items or services which are not reasonable and necessary for the diagnosis or treatment of illness or injury.

Code of Federal Regulations (CFR) References:

• CFR, Title 42, Volume 2, Chapter IV, Part 410.32(d)(3) Diagnostic x-ray tests, diagnostic laboratory tests, and other diagnostic tests: Conditions.
• CFR Title 42, Volume 2, Chapter IV, Part 410.33 Independent diagnostic testing facility.
• CFR, Title 42, Volume 2, Chapter IV, Part 414.50 Physician or other supplier billing for diagnostic tests performed or interpreted by a physician who does not share a practice with the billing physician or other supplier.
• CFR, Title 42, Volume 3, Chapter IV, Part 414.510 Laboratory date of service for clinical laboratory and pathology specimens.

Compliance with the provisions in this LCD may be monitored and addressed through post payment data analysis and subsequent medical review audits.

History/Background and/or General Information

Benign prostatic hyperplasia (BPH) is a histological diagnosis characterized by an increased number of epithelial and stromal cells in the prostate. It is most common in men over the age of 40, and the incidence increases with age. In the United States, 8 million men greater than 50-years-old suffer from BPH. In many cases BPH is asymptomatic, however, symptoms may occur due to prostate enlargement and compression of the urethra leading to bothersome lower urinary tract symptoms (LUTS), including voiding symptoms such as hesitancy, weak stream, straining, prolonged voiding, and storage symptoms (frequency, urgency, and nocturia). LUTS/BPH can have a significant impact on the quality of life and can cause serious complications such as infections, bleeding, calculus formation, urinary retention, and decline of renal function when untreated.¹ First line treatment generally consists of treatment with medications such as alpha blockers, PDE5 Inhibitors, or finasteride/dutasteride. If treatment with medications is not successful, surgical options may then be considered. Transurethral resection of the prostate (TURP) and open simple prostatectomy (OSP) are the standard surgical treatments for LUTS/BPH and are highly effective and provide improved outcomes in urinary functions. However, neither TURP nor OSP are without considerable perioperative complication and morbidity.² Transurethral waterjet ablation is a surgical-based therapy that combines image-guidance and robotics to remove prostatic tissue.³ The system works by pumping high pressure saline (500 to 8000 pounds per square inch [PSI]) through a probe nozzle to cut and dissect tissue at predetermined system parameters.³

Covered Indications

Treatment for LUTS/BPH will be considered reasonable and necessary when performed using an FDA approved/cleared device ONCE in patients with the following:

1. Indications including ALL of the following:
   1. Prostate volume of 30-150 mL.^4,5
   2. Persistent moderate to severe symptoms despite maximal medical management including ALL of the following:
   1. 1. International Prostate Symptom Score (IPSS) ≥12.
      2. Maximum urinary flow rate (Q_max) of ≤15 mL/s.^4,5
      3. Failure, contraindication, or intolerance to at least 3 months of conventional medical therapy for LUTS/BPH (e.g., alpha blocker, PDE5 Inhibitor, finasteride/dutasteride).

Limitations

The following are considered not reasonable and necessary:

1. Body mass index⁶ ≥42 kg/m².
2. Known or suspected prostate cancer (based on NCCN Prostate Cancer Early Detection guidelines⁷) or a prostate specific antigen (PSA) >10 ng/mL unless the patient has had a negative prostate biopsy within the last 6 months.⁸
3. Bladder cancer, neurogenic bladder, bladder calculus or clinically significant bladder diverticulum.⁶
4. Active urinary tract infection or systemic infection.⁹
5. Treatment for chronic prostatitis.⁶
6. Diagnosis of urethral stricture, meatal stenosis, or bladder neck contracture.⁶
7. Damaged external urinary sphincter.⁶
8. Known allergy to device materials.⁹
9. Inability to safely stop anticoagulants or antiplatelet agents preoperatively.⁹

CMS Internet-Only Manual, Pub 100-08, Medicare Program Integrity Manual, Chapter 13, §13.5.4 Reasonable and Necessary Provisions in an LCD states services will be considered reasonable and necessary only if performed by appropriately trained providers.

Patient safety and quality of care mandate that healthcare professionals who perform transurethral waterjet ablation of the prostate are appropriately trained and credentialed by a formal residency/fellowship program. Credentialing or privileges are required for procedures performed in inpatient and outpatient settings.

All aspects of care must be within the provider’s medical licensure and scope of practice.

Notice: Services performed for any given diagnosis must meet all the indications and limitations stated in this LCD, the general requirements for medical necessity as stated in CMS payment policy manuals, all existing CMS national coverage determinations, and all Medicare payment rules.

This evidence review focuses on transurethral waterjet ablation of the prostate, also known as Aquablation, and whether the evidence supporting this procedure provides certainty that it will result in improved health outcomes for the Medicare population. This review examines whether prostate volume size, PSA score, specific imaging for prostate volume measurement, maximum urinary flow rate (Q_max), and the presence of bladder calculus should limit who receives the transurethral waterjet procedure. In general, health outcomes of interest include patient mortality, morbidity, quality of life, and function.

For patients with BPH, transurethral waterjet ablation of the prostate endeavors to improve patient outcomes through an image-guided, robotics-assisted surgical procedure that minimizes adverse effects. First Coast sought patient-centered outcomes as the underlying justification for undergoing the transurethral waterjet ablation procedure. Therefore, a search for peer-reviewed literature was performed in PubMed to identify key clinical circumstances representing covered indications and limitations for performing the procedure. These included prostate volume size, known or suspected prostate cancer (e.g., PSA >10 ng/mL), specific imaging for prostate volume measurement, maximum urinary flow rate, and the presence of bladder calculus. Several searches were performed on PubMed, Google Scholar, and Google. Keywords and Boolean operators used in conjunction for the search were as follows: aquabeam*[tw] OR aqua beam*[tw] OR aquablation*[tw] OR waterablat*[tw] OR water ablat*[tw], waterjet[tw] OR water jet* AND ablat* AND procept OR prostat*, Transurethral waterjet ablat* OR aquablation AND prostat*, Transrectal ultrasound AND prostate AND MRI AND prostate volume. Beyond industry sponsored studies, only a few peer-reviewed papers have been published addressing the performance of transurethral waterjet ablation of the prostate and/or Aquablation. Search limitations included studies that were only adult-focused (≥19 years of age), human subject, and English language. The search identified 65 studies which were chosen for in-depth review following the title and abstract appraisal. Of the 65 studies, 35 were included for analysis and 30 were excluded for relevancy. Additionally, 2 FDA 510(k) Premarket Notification Database letters were submitted with the reconsideration request and were reviewed.

Pivotal Studies

Initial clinical experience for transurethral waterjet ablation of the prostate was reported in 2016.¹⁰ After FDA clearance in 2017, this technology was further studied with the publication of the WATER trial, a PHASE III multicenter, international, double-blinded, randomized, non-inferiority study with 181 subjects compared Aquablation (N=116) to TURP (N=65).^11,12 Men 45 to 80-years-old with prostate size 30-80 cc (by TRUS), moderate-to-severe LUTS (International Prostate Symptom Score [IPSS] ≥12), and maximum urinary flow rate (Q_max) <15 mL/s were included, and stringent exclusion criteria were applied. Although treatment was performed by an unblinded research team, after randomization a separate blinded team performed all follow-up. The primary endpoint was the change in the IPSS at 6 months; scores decreased by 16.9 points for Aquablation and by 16.1 points for TURP, respectively (non-inferiority P < .001 and superiority P = .13). The primary safety endpoint was the proportion of subjects with adverse events, defined as Clavien-Dindo grade 2 or higher or any grade 1 with persistent disability. The 3 month primary safety endpoint rate was lower in the Aquablation group than in the TURP group (26% vs. 42%; P = .015). At 2 years, IPSS score improvement was sustained (Δ_IPSS = 14.7 in Aquablation and 14.9 in TURP [P = .83; 95% CI for difference -2.1 to 2.6]), and Q_max improvement was large in both groups (11.2 and 8.6 cc/s for Aquablation and TURP, respectively [P = .19; 95% CI for difference -1.3 to 6.4]).¹³ These results demonstrated that Aquablation was as effective, if not more effective, as to the standard TURP procedure. The 2 year reduction in post-void residual volume (PVR) was 57 cc and 70 cc for Aquablation and TURP, respectively (P = .39). PSA decreased significantly in both groups by 1 point (P < .01). Re-treatment rates were 4.3% and 1.5% (P = .42) in the Aquablation and TURP groups, respectively. Among the subset of sexually active men without the condition at baseline, anejaculation was less common after Aquablation (10% vs. 36%; P = .0003). When post-Aquablation cautery was avoided rates of anejaculation were lower (7% vs.16%; P = .18), and this resulted in reduced grade 1 persistent events identified in the Aquablation group. The authors believe that Aquablation avoids damage to tissues involved in ejaculation through precise, image-based targeting, and robotic execution. The limitations of the study include the risk of performance bias, as surgeons were not blinded, and unknown generalizability to a more heterogeneous US population as it is a single-center study of males ages 50-80 years in New Zealand. The 3 year results were essentially unchanged.⁴

A 2019 Cochrane Review based on the 1 year Aquablation trial results found comparable results, with TURP to be of moderate certainty related to the IPSS primary outcome measure. All other metrics were graded from low-certainty to very low-certainty (adverse events, retreatments, erectile function, ejaculatory dysfunction).³ The certainty of studied outcomes was downgraded due to study limitations (performance, reporting, and attrition bias) and imprecision (e.g., confidence intervals that crossed the assumed thresholds of clinically significant differences or few events, or both). For example, both sexual outcome (erectile and ejaculatory function) results were downgraded 2 levels for a combination of imprecision and study limitations (substantial risk of performance and attrition bias). The authors recommended larger, more rigorously conducted, and transparently reported studies comparing Aquablation to other techniques (laser enucleation, prostatic urethral lift, robotic-assisted simple prostatectomy) for which there is also increasing interest.

In a study by Nguyen et al,⁶ the authors aimed to determine if the effectiveness of Aquablation is independent of prostate size by comparing its outcomes in 2 clinical trials. The first trial that was conducted was with men whose prostate was between 30 and 80 mL (WATER I) and the other trial was conducted with men whose prostates were between 80 and 150 mL (WATER II). WATER I trial was a prospective, double-blind, multicenter, international clinical trial comparing the safety and efficacy of Aquablation and TURP as surgical treatments of LUTS due to BPH in men aged 45 to 80 years with a prostate volume between 30 and 80 mL, as measured by TRUS. Patients were enrolled at 17 centers.¹² One hundred sixteen men participated. The WATER II trial was a prospective, multicenter, international clinical trial of Aquablation for the surgical treatment of LUTS/BPH in men aged 45 to 80 years with a prostate volume between 80 and 150 mL, as measured by TRUS.¹⁴ Patients were enrolled at 13 US and 3 Canadian sites. One hundred one men participated. The study’s parameters included patients who completed the IPSS. Patients completed questionnaires such as the Incontinence Severity Index (ISI), the International Index of Erectile Function (IIEF-5), and the Male Sexual Health Questionnaire for Ejaculatory Dysfunction (MSHQ-EjD). Patients received uroflowmetry, PVR measurements, and underwent standard laboratory blood assessments. These questionnaires and measurements were provided at baseline. PVR and lab tests were also required at 1- and 3-months postoperatively. The clinical events committee graded adverse events using the Clavien-Dindo classification and rated their causation as possibly, probably, or definitely related to the study procedure for 3 months after treatment. The inclusion and exclusion criteria were the same for both studies. The inclusion criteria included patients with moderate-to-severe symptoms indicated by a baseline IPSS of ≥12 and a maximum urinary flow rate (Q_max) of <15 mL/s. Exclusion criteria included patients with a body mass index (BMI; calculated as weight in kilograms divided by height in meters squared) of ≥42 kg/m², a history of prostate or bladder cancer, neurogenic bladder, bladder calculus or clinically significant bladder diverticulum, active infection, treatment for chronic prostatitis, diagnosis of urethral stricture, meatal stenosis or bladder neck contracture, a damaged external urinary sphincter, stress urinary incontinence, PVR >300 mL, or urinary retention. The comparison between the 2 studies revealed the mean operative time for WATER I was 33 minutes and 37 minutes for WATER II. The actual treatment time was 4 minutes (WATER I) and 8 minutes (WATER II). For IPSS, the mean change at 12 months averaged 15.1 for WATER I and 17.1 for WATER II (P = .60). Adverse events of Clavien-Dindo grade ≥2 occurred in 19.8% of WATER I patients and 34.7% of WATER II patients (P = .47) at 3 months post-operatively.⁶ The authors concluded that the outcomes and effectiveness of Aquablation are comparable, and are independent of prostate size, with the expectation that with larger prostates a higher risk of complication is possible.

In the April 2020 publication of WATER II by Desai et al,⁵ 2 year safety and effectiveness data of the Aquablation procedure in men with symptomatic benign prostatic hyperplasia (BPH) and large volume prostates (80-150 cc) were evaluated. Enrolled participants averaged a prostate volume of 107 cc, a group typically excluded from undergoing TURP. The evidence supports superior improvements from Aquablation at mid-term (2 year) follow-up and quality long-term results for the treatment of LUTS related to BPH.

Specialty Society Guidelines and Systematic Reviews

Per recent guidelines from the American Urological Association (AUA), robotic waterjet ablation requires general anesthesia and is not considered to be a minimally invasive surgical treatment (MIST).¹⁵ Based on the WATER I study results the AUA found parity between Aquablation and TURP on IPSS, LUTS, and quality of life (QOL) scores (Quality of Evidence: Moderate). Their recommendation was: “Aquablation may be offered to patients with LUTS attributed to BPH provided prostate volume >30/<80g; however, patients should be informed that long-term evidence of efficacy and re-treatment rates remains limited”¹⁶ (Conditional Recommendation; Evidence Level: Grade C).

Guidelines from the Canadian Urological Association (CUA) published in 2018 also give a “conditional recommendation based on moderate-quality evidence” that Aquablation may be offered to men “interested in preserving ejaculatory function, with prostates <80 cc, with or without a middle lobe.”¹⁷

In 2018, a systematic review from the National Institute for Health and Care Excellence (NICE) was published, based on 6 month WATER I trial results, which concluded the Aquablation procedure should only be used with “special arrangements,” a defined designation which indicates that there are uncertainties about safety and effectiveness.¹⁸

Summary of Evidence: Patient Age

The original studies did not evaluate the use of this procedure in men greater than or equal to the age of 80 years, therefore, safety and efficacy data was lacking in that population. Additional literature was submitted and reviewed that included men ≥80 years of age.

Gilling et al in a 2022 publication, reported the results of a double-blinded, randomized, and controlled trial conducted at multiple centers with a 5 year follow-up comparing patients that received TURP versus transurethral waterjet ablation.¹⁹ One hundred eighty-four men aged 45 to 80 years with LUTS secondary to BPH were studied comparing the safety and efficacy of Aquablation and TURP for those with moderate-to-severe symptoms as measured by IPSS and maximum urinary flow rate (Q_max). The primary safety endpoint was the proportion of subjects with adverse events rated by the clinical events committee as possibly, probably, or definitely related to the study procedure. The primary efficacy endpoint was the change in IPSS from baseline to 6 months. Secondary safety endpoints included resection time, total operative time, length of hospital stay, reoperation or reintervention rate, the proportion of sexually active subjects reporting worsening sexual function, and the proportion of subjects with a serious device or procedure-related adverse event. Primary safety endpoints were successfully achieved at 3 months as the Aquablation study group had a lower event rate than the TURP study group. Procedure-related ejaculatory dysfunction was lower for Aquablation. The primary efficacy endpoint was successfully achieved at 6 months, where the mean IPSS score decreased from baseline by 16.9 points for Aquablation and 15.1 points for TURP. The mean difference in change score at 6 months was 1.8 points greater for the Aquablation study group. At 5 years, IPSS scores improved by 15.1 points in the Aquablation study group and 13.2 points in the TURP study group (P = .28). For men with larger prostates (≥ 50 mL) IPSS reduction was 3.5 points greater across all follow up visits in the Aquablation study group compared to the TURP study group (P = .01). Improvement in peak urinary flow rate was 125% and 89% compared to baseline for Aquablation and TURP, respectively. The risk of patients needing secondary BPH therapy, defined as needing BPH medication or surgical intervention, up to 5 years due to recurrent LUTS was 51% less in the Aquablation study arm compared to the TURP study arm. The authors of the study observed that the Aquablation procedure improved BPH-related urinary symptoms compared to the referenced standard treatment (TURP) over 5 years.¹⁹ Study limitations included lower than expected follow-up percentages at 4- and 5-years which the authors attributed to the COVID-19 pandemic, non-US based study facilitation, and author identified conflict of interests.

An additional retrospective observational study published in 2020,²⁰ documented the use of Aquablation at a single center in the United States. This study was comprised of 55 men with a mean prostate volume of 100 cc (range 27-252 cc) and a prominent obstructing middle lobe in 85% of them. Baseline assessment and a follow-up assessment at 3 months were completed. A substantial improvement of 80% (17 points) was seen in BPH symptoms scores. Q_max, measured by flowmetry, improved by 182% (14 mL/s). IPSS QOL scores improved by 3.3 points.²⁰ The age of male subjects included those >80 years of age (range 50 to 84-years-old), but the actual number of subjects over 80 years was not reported. Limitations for this study included a small sample size, the observational study design, and a short follow-up period.

Analysis of Evidence: Patient Age

In summary, the promising short-term, single-study Aquablation data has resulted in conditional recommendations in some guidelines (e.g., AUA, CUA, NICE). A conditional recommendation with Grade C evidence level (AUA) which translates to “balance between benefits & risks/burdens is unclear, alternative strategies may be equally reasonable, better evidence likely to change confidence”, echoing the Cochrane Review recommendation: “any recommendation for or against the use of Aquablation would be based on only very low-certainty evidence.”³ However, these guideline recommendations predate publication of mid-term (3 year) results, which demonstrate persistent similar outcome with TURP.⁴

Two of the articles submitted with the reconsideration request provided a moderate certainty of evidence^20,21 in the demonstrated safety and efficacy of this procedure in those equal to and greater than 80 years of age. Additionally, the study by Gilling et al provided strong¹⁹ certainty of evidence based on risk of bias (ROB) analysis for the safety and efficacy of this procedure in those 80 years of age or older. Specifically, the 5 year trial data by Gilling et al¹⁹ shows positive long-term outcomes with an improvement in IPSS scores of 15.1 in the Aquablation group and 13.2 in TURP, 125% improvement in urinary flow rate compared to baseline for the Aquablation group, a lower risk of secondary BPH therapy at 5 years, and a less invasive approach in patients 80 years of age or older that may be beneficial. Therefore, given the absence of proven harm and evidence supporting safety and efficacy in patients 80 years of age or older, the age limitation has been removed from the policy. Based on the 2- and 3-year study results combined with recommendations from the AUA and CUA, transurethral waterjet ablation treatment of LUTS/BPH is considered reasonable and necessary when performed as outlined in this LCD.

Summary of Evidence: Prostate Volume

Three publications were identified which addressed the use of Aquablation for prostates over 150 cc in size.^20,22,23 A retrospective observational study published in 2020,²⁰ documented the use of Aquablation at a single center in the United States. This study was comprised of 55 men with a mean prostate volume of 100 cc (range 27-252 cc) and a prominent obstructing middle lobe in 85% of them. Baseline assessment and a follow-up assessment at 3 months were completed. A substantial improvement of 80% (17 points) was seen in BPH symptoms scores. Q_max, measured by flowmetry, improved by 182% (14 mL/s). IPSS QOL improved by 3.3 points.²⁰ The range of prostate sizes did include prostates over 150 cc, but the actual number of subjects over 150 cc was not reported. Limitations for this study included a small sample size, the observational study design, and a short follow-up period.

An additional retrospective observational study by Helfand et al investigated the use of Aquablation in 251 men with LUTS secondary to BPH who have very large prostates (>150 mL).²² Aquablation resulted in an improved Q_max with an increase from 7 mL/s to 19 mL/s (P < .001) and an improved IPSS score from 19 to 7 for men with prostates >150 mL. No significant differences were found in terms of IPSS, QOL, or uroflowmetry based on prostate volume group. Limitations of this study included the retrospective nature of the study, the use of historic data in controlled clinical trials to create the comparison groups, and a short follow-up. The largest limitation of the study however was that while the study was aimed at examining prostates over 150 mL, only 34 (14%) of the study participants had prostates >150 mL in size, preventing the overall results from being generalized to the population at which the LCD limitation is addressed.

The final piece of reviewed literature was an editorial companion piece published in 2022 by Helfand et al highlighting physician’s real-world experience using Aquablation in men with LUTS, secondary to BPH, who have prostates >150 mL.²³ This editorial references the data used in the above-described study by Helfand et al 2021. The publication explains that the surgical options for men with prostates >150 mL are limited. Currently, the options include simple prostatectomy, anatomic enucleation of the prostate, and waterjet ablation. For waterjet ablation in men with very large prostates, there are some additional surgical steps not found in surgeries for those with smaller prostates. While the procedure for very large prostates begins the same way as average sized prostates, because of the length and depth of the prostate as well as the size of the handpiece for operating, multiple passes of the waterjet are required during the operation. Likewise, if the prostate length is greater than 7 cm, the scope tip will not reach the internal sphincter so additional planning is required in transverse view. Due to the multiple planning periods, adjustments of the handpiece, and swipes of the beam, Aquablation in very large prostates does have additional procedure-related risks such as a greater chance for bleeding. Limitations of this article include the small sample size, high risk of bias due to the observational real-world evidence referenced, and the paper's editorial nature.

Analysis of Evidence: Prostate Volume

Based on the submitted and searched literature this contractor has determined that the literature is insufficient to support the removal of the prostate volume limitation from covered indications. In the study by Kasraeian et al,²⁰ men with larger prostatic volumes were recorded, however, the average volume was 100 cc, and the study does not show sufficient evidence of safety and efficacy in men with larger prostates (>150 cc). The papers by Helfand et al showed minimal-to-moderate positive outcomes for patients with prostates over 150 mL, but the lack of long-term data, small sample size, and changes in procedure required do not support the removal of the volume endpoint as written in the LCD.

At this current time, there is a lack of evidence to prove the clinical utility and safety of transurethral waterjet ablation in prostates over 150 mL. The pivotal studies comparing transurethral waterjet ablation and TURP procedures were limited to patients with average to smaller size prostates. The original study by Gilling et al examining the safety and efficacy of robot-assisted waterjet ablation of the prostate only included men with prostates under 85 mL (mean size 54 mL).¹⁰ The WATER II trial by Desai et al studied prostates 80-150 mL with a mean prostate size of 107.4 mL.²⁴ The study by Helfand et al analyzed above, aimed at examining prostates over 150 mL, but only 34 (14%) of the study participants had prostates >150 mL in size.²² Overall, there is a paucity of evidence establishing long-term safety and efficacy outcomes that directly compare transurethral waterjet ablation to TURP, with a larger sample size of prostates >150 mL that prove the safety of this procedure in very large prostates. Given the low certainty of the current evidence that transurethral waterjet ablation in prostates >150 mL is safe and effective, the covered indication endpoint will not change.

Summary of Evidence: PSA Score

Peer-reviewed studies on the usefulness of the prostate-specific antigen (PSA) score in evaluating patients for transurethral waterjet ablation of the prostate were sought and analyzed. One study addressed the oncological outcomes for patients undergoing Aquablation with varying PSA scores.⁸ Hilscher and colleagues (2022)⁸ performed a pooled analysis of 63 781 men who underwent a TURP to analyze the risk of prostate cancer incidence and mortality following a benign histological assessment. The study found that 10 year risks of any prostate cancer and prostate cancer with a Gleason score ≥ 3+4, and the 15 year risk of prostate cancer death, showed a clear relationship on a scatterplot with increasing PSA. The 15 year cumulative incidence of prostate cancer-specific death after benign TURP was 1.4% (95% confidence interval [CI], 1.3%–1.6%) for all men and .8% (95% CI,.6%–1.1%) for men with PSA levels <10 ng/mL.⁸ It was concluded that there was little to no risk of adverse oncological outcomes for patients with PSA below 10 ng/mL at the time of transurethral resection of the prostate, but the authors did note that more extensive follow-up may be needed for those with higher PSA levels. The National Comprehensive Cancer Network (NCCN) 2024 Prostate Cancer guidelines were also appraised for their guidance for patients with varying levels of prostate cancer and PSA scores.²⁵ Management of suspected prostate cancer is dependent on a multi-factorial risk profile. Literature evaluating the use of transurethral waterjet ablation in known or suspected prostate cancer patients based only on PSA level was not found.

Analysis of Evidence: PSA Score

The intended patient population studied to validate the safety and efficacy of transurethral waterjet ablation of the prostate were patients with a non-malignant prostate condition.^{4,10-13,19,24} Moreover, there is no literature that establishes safety, efficacy, or intended use of waterjet ablation use in patients with known or suspected prostate cancer. The current policy restricts transurethral waterjet ablation for individuals with PSA levels >10 ng/mL and, as such, the Hilscher study provides evidence in favor of the current PSA restrictions.⁸ Based on the literature submitted and researched, these levels reliably classify the intended patient population, specifically, those with benign prostate conditions. The NCCN guideline includes PSA levels to define risk groups for prostate cancer. Concern exists for the possibility of overtreatment of benign conditions as related to the increased diagnosis of early prostate cancer from PSA testing. The United States Preventative Task Force (USPSTF) and NCCN have further updated their guidelines to recommend PSA alongside imaging and other biomarkers to improve specificity and provide more individualized healthcare decision making. Overall, the NCCN guidelines do not establish a role for waterjet ablation in patients with known or suspected prostate cancer. There is no literature that demonstrates patient-centered outcomes for transurethral waterjet ablation in the setting of prostate cancer when conservative management is a preferred or recommended course of treatment. However, the study by Hilscher and colleagues found little to no risk adverse oncological outcomes for patients with PSA below 10 ng/mL at the time of transurethral resection of the prostate. Based on both the submitted and identified literature, this contractor has determined that the evidence is insufficient to support the removal of suspected or known prostate cancer individuals from the limitations. Therefore, this limitation will remain.

Summary of Evidence: Q_max and Voided Volume

Peer-reviewed literature focused on providing information on the safety and effectiveness of performing transurethral waterjet ablation of the prostate in patients with Q_max ≤15 mL/s (voided volume greater than 125 cc) was sought and analyzed. Four publications were identified which addressed the safety of performing transurethral waterjet ablation of the prostate in patients with retention abilities and showed the effectiveness of the procedure on Q_max. Additionally, the WATER II trial, which has been mentioned in previous sections, included cohorts of catheter-dependent patients who could not pass meaningful amounts of urine, and therefore could not undergo a flow rate test that requires 125 cc of volume voided. This cohort of catheter-dependent patients,²⁴ demonstrated benefit from undergoing the Aquablation procedure. AUA guidelines on the Management of LUTS Attributed to BPH, published in 2021, addressed the treatment of patients in urinary retention.¹⁵ The guideline states that indications for surgery include “a desire by the patient to avoid taking a daily medication, failure of medical therapy to sufficiently ameliorate bothersome LUTS, intolerable pharmaceutical side effects, and/or the following conditions resulting from BPH and for which medical therapy is insufficient: acute and/or chronic renal insufficiency, refractory urinary retention, recurrent urinary tract infections (UTIs), recurrent bladder stones, and recalcitrant gross hematuria.”¹⁵ The guideline identifies Robotic Waterjet Treatment (e.g., Aquablation) as a treatment option for patients with LUTS/BPH provided that the prostate volume ranges between 30-80 cc.¹⁵

Additional peer-reviewed literature has demonstrated that Aquablation is clinically effective and safe in patients with catheter-dependent urinary retention. Burton et al compared outcomes of Aquablation in men with acute and chronic urinary retention.²⁶ This retrospective study of 113 men (69 not in retention, 28 with acute retention and 16 with chronic retention) found no difference in utilization of postoperative prostate medications, complications, IPSS, or uroflowmetry between men with acute, chronic, or no retention. There was no significant difference for men using intermittent catheterization as compared to those with an indwelling catheter prior to surgery in relation to the ability to return to spontaneous voiding faster (P = .31). The study found that 98% of participants achieved spontaneous voiding after Aquablation regardless of preoperative urodynamic status. Limitations of this study included small sample sizes for acute and chronic patients, preoperative urodynamics not routinely obtained for all patients, and the study's retrospective nature.

A prospective observational study addressed a cohort of 60 men with significant BPH who underwent Aquablation at a single ambulatory surgery center.²⁷ Results showed significant improvements in urinary flow rates and significant reductions in IPSS scores at 1 month post-operatively. The occurrence of pain post Aquablation procedure was infrequent and the incidence of postoperative complications, including urinary retention, was infrequent and in alignment with previously published outcomes. The mean 1 month Q_max increased to 26 mL/s and the mean PVR volume decreased to 39 mL. The authors noted several limitations that include a short follow-up time, a small sample size, performance in a single center study, and an accompanying selection bias.

Finally, a prospective observational study by Labban et al published in 2021,²⁸ assessed 59 consecutive patients who underwent Aquablation at a tertiary care center. The study population included 14 patients in urinary retention. At the 3 month follow-up, significant drops in PSA score, prostate size, and IPSS (P < .001 for all) were observed. PVR volume was reduced significantly –186 ± 82 mL (P = .01). A sub-analysis among patients with retention at baseline revealed a similar operative time (P = .38), length of catheterization (P = .53), and length of hospital stay (P = .94) when compared to patients not in urinary retention. The study had limitations which included a small sample size and the lack of a control group. Despite these limitations, the results of this study echo the findings of other studies that confirmed improved voiding parameters and decreased LUTS.

Analysis of Evidence: Qmax and Voided Volume

Overall, there is strong evidence to continue the use of Q_max as a measurement for urinary retention. Additionally, there is moderate evidence supporting the use of transurethral waterjet ablation for patients with urinary retention.^15,26-28 Based on the submitted and identified literature, it was determined that there is sufficient evidence to support removing the voided volume requirement from the covered indications. Consequently, the minimum 125 cc voided volume reference has been removed from the LCD.

Summary of Evidence: Bladder Calculus

Peer-reviewed literature on the safety and effectiveness of performing benign prostatic hyperplasia (BPH) surgery in patients who may have bladder stones or need both BPH surgery and bladder stone removal (BS) procedures were analyzed. No studies were identified using waterjet ablation of the prostate in setting of bladder calculus. A retrospective study comparing surgery for both BPH and bladder stones,²⁹ and an updated AUA guideline paper were identified.¹⁶ Both articles addressed the safety and efficacy of performing BPH surgery in patients who may have bladder calculus. Chapelle et al retrospectively reviewed 179 men over the age of 50 years who underwent BS removal, with or without concomitant BPH surgery.²⁹ The outcome criteria used in this study were early postoperative complications, stone recurrence, subsequent surgery for BS or BPH, and late surgical complications. An aggregate score ranging from 0 to 4 was calculated by combining the four criteria, with 4 representing successes in all categories. One hundred seven patients were in the concomitant surgical treatment (CST) group and 72 patients in the bladder stone removal alone (SRA) group. The patients who underwent CST had a significantly lower rate of BS recurrence (12% vs. 39%; P = .001) and underwent fewer consequent surgeries (P < .001). There was an observed difference in composite score between the CST and SRA groups, but the difference was not significant (3.07 vs. 2.72, P = .08). Fifty-one percent of patients in the CST group had early complications (e.g., acute urinary retention with and without infection, bladder clots, urinary urgency, ICU admission, death) compared to 35% of the SRA group (P = .17). After one-month, late complications included urinary incontinence (15% for CST and 6% for SRA, P = .092), and de novo urethral stenosis (4% CST and 7% SRA group, P = .491). In this study a significant number of patients (44%) in the SRA group still required subsequent stone removal or BPH surgery. Based on this study, the combined surgical approach for the removal of prostate and bladder calculi may result in greater harm than the anticipated clinical benefits. Additionally, this approach does not consistently eliminate the need for subsequent procedures. The authors conclude that it there is insufficient support for the routine use of a combined surgical approach for treating both BPH and BS at the time of initial management and that further larger studies of a prospective nature are needed.

In 2023, Sandhu et al published an amendment to the American Urological Association (AUA) guideline for “Management of Lower Urinary Tract Symptoms Attributed to Benign Prostatic Hyperplasia (BPH).”¹⁶ The purpose of this amendment was to add additional evidence-based management guidance of male LUTS secondary to BPH. The AUA guidelines provide a single surgical recommendation on bladder stones which states that, “Surgery is recommended for patients who have renal insufficiency secondary to BPH, refractory urinary retention secondary to BPH, recurrent urinary tract infections (UTIs), recurrent bladder stones or gross hematuria due to BPH, and/or with LUTS/BPH refractory to or unwilling to use other therapies.”¹⁶ Surgery is recommended for bladder stone patients only for whom medical therapy is insufficient. Multiple surgical options were identified in the guideline (e.g., MIST, prostatectomy, and transurethral surgery), however there was no recommendation for the use of transurethral waterjet ablation (e.g., Aquablation) in this clinical scenario.

Analysis of Evidence: Bladder Calculus

There were several limitations noted. The Chapelle et al study design was retrospective therefore there is a high risk of protopathic bias, confusing the cause-and-effect relationship, as well as unknown effects from confounding variables.²⁹ Moreover, there is a high risk of selection bias since the procedures were performed at 2 university hospitals which tend to represent more resource rich environments as compared to a community hospital. For example, advanced equipment and specialized staff typically available at tertiary centers like university hospitals might not be available in rural settings. The study could also be subject to selection bias as the authors assumed that fragile patients (i.e., heart disease, anticoagulant treatment, etc.) were more often referred to SRA, to limit morbidity. Lastly, the smaller number of patients included could mean that small, but clinically significant differences between the groups, might not have been detected.

In summary, this contractor has determined that there is insufficient evidence (based on the small sample sizes, high risk of bias, and lack of supporting evidence for AUA recommendations) to support the use of waterjet ablation in the presence of bladder calculus provided by the submitted and identified literature. Additionally, the pivotal studies (e.g., WATER I and II trials) did not include patients with bladder stones so, there is no data on Aquablation in patients with bladder stones, and no data on patients undergoing concomitant prostate Aquablation and bladder stone removal. The identified literature does not support the removal of the bladder calculus limitation in the LCD and for these reasons, bladder calculus will not be removed from the coverage limitations.

Summary of Evidence: Prostate Volume Measurement

PubMed and Google Scholar were searched for peer-reviewed, evidence-based literature providing information on the analytic and clinical validity and clinical utility of transrectal ultrasound (TRUS) and Magnetic Resonance Imaging (MRI). Keywords used in the search were transrectal ultrasound and prostate and MRI and prostate volume.

A total of 2 publications, observational studies of retrospective nature, addressed the analytical validity of MRI and TRUS for prostate volume measurement.^30,31 Studies excluded from analysis included systematic reviews with a low certainty of evidence,^32,33 studies focusing on Prostate-Specific Antigen Density (PSAD)³⁴ and studies addressing the clinical utility of MRI-targeted biopsy,³⁵ which is beyond the scope of this policy.

Bezinque et al retrospectively reviewed records of 99 patients who underwent radical prostatectomy within 1 year of multiparametric prostate MRI (mpMRI) to determine optimal prostate volume (PV) measurement techniques.³⁰ The reference used was manual segmentation by a radiologist (MRI-R3D). MRI based methods were found to be the most reliable, with stronger intra-class correlation coefficients of .91 for manual segmentation by a third-year medical student (MRI-S3D) and .90 for MRI-ellipsoid formula. Digital rectal examinations (DRE) were the least reliable (.33). Although transrectal ultrasound (TRUS) yielded less favorable results (.71), it remains a useful tool for PV measurement as it is reliable, reasonably accurate, and commonly used when mpMRI is not performed.³⁰

In addition to the retrospective nature of this study, the authors have noted several limitations. These include small sample size, the failure to use surgical specimens as a reference standard, which may have provided more accurate PV measurements, and lack standardization between participating institutions. Therefore, interobserver variation could not be assessed, as a single radiologist performed the reference measurements, and a single urologist determined DRE and TRUS measurements. Other studies have shown low interobserver variability for MRI in PV assessments, thereby minimizing concern for MRI-R3D as the reference standard. The outcomes may have been affected by changes in prostate sizes within 1 year of mpMRI, as well as the absence of CT segmentation data for PV to compare with other methods. Due to the average younger age of 63 years (range of 59-68) and undergoing radical prostatectomy in the study cohort, results also may not be fully generalizable to the Medicare population, and outcomes may have differed for those older or without prostate cancer.³⁰

Analytical validity was assessed by Weiss et al in a retrospective comparison of preoperative transrectal ultrasound (TRUS) versus endorectal MRI (eMRI) in 756 patients diagnosed and treated for localized prostate cancer. A high correlation was found between the 2 methods in estimating prostate volume using the prolate ellipsoid formula. There was a significant correlation for average prostate size measured (R=.801; P < .001), as well as a strong linear relationship. The average difference in measurement in TRUS relative to eMRI was 1.7 mL, showing statistical significance (P < .001), without clinical relevance. These conclusions support the use of TRUS for prostate volume measurement in patients with prostatic disease due to its accuracy, reproducibility, and efficacy, despite the superiority of MRI based estimation of prostate size.³¹

Analysis of Evidence: Prostate Volume Measurement

Study limitations include its retrospective nature, the use of differing measurement methods, not estimating TRUS and eMRI volumes with the same units. The accuracy of imaging techniques was not verified with more precise methods such as planimetry-based estimations or anatomical specimens. Additionally, a notable limitation is that this study population consists of prostate cancer patients with mean age of 59 years (interquartile range 9) which may not be generalizable to older Medicare populations that do not have prostate cancer.³¹

In summary, the body of peer-reviewed evidence does not support specific measurement techniques as superior or preferred for prostate volume determination. Although MRI is shown to be slightly more accurate, the certainty of evidence supports that TRUS provides comparable results and is a useful tool often recommended due to its reliability, especially when MRI is unavailable or contraindicated.^30,31 Therefore, TRUS is no longer the only imaging modality required to determine the prostate volume.

Summary Rationale for Reconsideration

Based on the evidentiary review summarized by the preceding text, coverage expansion is granted through removal of the age limitation, the Q_max voided volume specification, and the imaging modality requirement for determining prostate volume. All other indications and limitations remain unchanged.

Please refer to the related Billing and Coding Article: Transurethral Waterjet Ablation of the Prostate (A58264) for documentation and utilization requirements as applicable.

This bibliography presents those sources that were obtained during the development of this policy. The Contractor is not responsible for the continuing viability of website addresses listed below.

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9. Administration UFaD. FDA Approval: De Novo Classification Request for AQUABEAM System.
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19. Gilling P, Barber N, Bidair M, et al. Five-year outcomes for Aquablation therapy compared to TURP: results from a double-blind, randomized trial in men with LUTS due to BPH. Can J Urol. 2022;29(1):10960-10968.
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22. Helfand BT, Glaser AP, Kasraeian A, et al. Men with lower urinary tract symptoms secondary to BPH undergoing Aquablation with very large prostates (> 150 mL). Can J Urol. 2021;28(6):10884-10888.
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29. Chapelle C, Lavallee E, Vallee M, Descazeaud A. Bicentric retrospective study comparing the postoperative outcomes of patients treated surgically for bladder stones with or without concomitant surgery for BPH. World J Urol. Jan 8 2024;42(1):13. doi:10.1007/s00345-023-04699-z.
30. Bezinque A, Moriarity A, Farrell C, Peabody H, Noyes SL, Lane BR. Determination of Prostate Volume: A Comparison of Contemporary Methods. Acad Radiol. Dec 2018;25(12):1582-1587. doi:10.1016/j.acra.2018.03.014.
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33. Wang S, Kozarek J, Russell R, et al. Diagnostic Performance of Prostate-specific Antigen Density for Detecting Clinically Significant Prostate Cancer in the Era of Magnetic Resonance Imaging: A Systematic Review and Meta-analysis. Eur Urol Oncol. Apr 2024;7(2):189-203. doi:10.1016/j.euo.2023.08.002.
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35. Hugosson J, Godtman RA, Wallstrom J, et al. Results after Four Years of Screening for Prostate Cancer with PSA and MRI. N Engl J Med. 2024;39(12):1083-1095. doi:10.1056/NEJMoa2406050.
36. Bach T, Giannakis I, Bachmann A, et al. Aquablation of the prostate: single-center results of a non-selected, consecutive patient cohort. World J Urol. Jul 2019;37(7):1369-1375. doi:10.1007/s00345-018-2509-y.
37. Bach T, Gilling P, El Hajj A, Anderson P, Barber N. First Multi-Center All-Comers Study for the Aquablation Procedure. J Clin Med. Feb 24 2020;9(2)doi:10.3390/jcm9020603.
38. Bhojani N, Nguyen DD, Kaufman RP, Jr., Elterman D, Zorn KC. Comparison of < 100 cc prostates and > 100 cc prostates undergoing aquablation for benign prostatic hyperplasia. World J Urol. Jul 2019;37(7):1361-1368. doi:10.1007/s00345-018-2535-9.
39. Bhojani N, Bidair M, Zorn KC, et al. Aquablation for Benign Prostatic Hyperplasia in Large Prostates (80-150 cc): 1-Year Results. Urology. Jul 2019;129:1-7. doi:10.1016/j.urology.2019.04.029.
40. Bhojani N, Bidair M, Kramolowsky E, et al. Aquablation Therapy in Large Prostates (80-150 mL) for Lower Urinary Tract Symptoms Due to Benign Prostatic Hyperplasia: Final WATER II 5-Year Clinical Trial Results. J Urol. Jul 2023;210(1):143-153. doi:10.1097/JU.0000000000003483.
41. Brierly RD, Mostafid AH, Kontothanassis D, Thomas PJ, Fletcher MS, Harrison NW. Is transurethral resection of the prostate safe and effective in the over 80-year-old? Ann R Coll Surg Engl. Jan 2001;83(1):50-3.
42. Chughtai B, Thomas D. Pooled Aquablation Results for American Men with Lower Urinary Tract Symptoms due to Benign Prostatic Hyperplasia in Large Prostates (60-150 cc). Adv Ther. Jun 2018;35(6):832-838. doi:10.1007/s12325-018-0722-0.
43. D'Agostino D, Colicchia M, Corsi P, et al. The combination of waterjet ablation (Aquabeam(®)) and holmium laser power for treatment of symptomatic benign prostatic hyperplasia: early functional results. Cent European J Urol. 2021;74(2):222-228. doi:10.5173/ceju.2021.0049.
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64. Administration UFaD. 21 CFR§ 876.4350. 501(k) Premarket Notification Database. 2023;
65. Administration UFaD. 21 CFR 876.4350. 501(k) Premarket Notification Database. July 19, 2024 2024;

• Lower urinary tract symptoms (LUTS),
• Benign prostatic hyperplasia (BPH),
• Waterjet ablation,
• Aquablation