Flexible Ureteroscopy With Tip-Bendable Suction Ureteral Access Sheath Versus Mini-Percutaneous Nephrolithotomy for Treatment of 2-3cm Renal Stones: an International Multicentre, Randomized, Parallel-Group, Non-Inferiority Trial
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- Enrollment
- 720
- Locations
- 1
- Primary Endpoint
- Immediately stone-free rate (SFR)
Study Overview
Brief Summary
Background: Percutaneous nephrolithotomy (PCNL) is the first-line treatment for renal stones larger than 2 cm according to EAU and AUA guidelines. Advances in flexible ureteroscopy, including smaller disposable ureteroscopes and suction techniques, have expanded its indications. The tip-bendable suction ureteral access sheath (S-UAS) offers improved flexibility and stone-free rates (SFR). This study compares clinical outcomes of flexible ureteroscopy (f-URS) with S-UAS and mini-PCNL in treating 2-3 cm renal stones.
Objective: This study aims to determine if f-URS with S-UAS is non-inferior to mini-PCNL regarding stone-free rates. Secondary objectives include comparing complication rates, surgical time, and hospitalization duration.
Methods: This multicenter, international, prospective, non-inferiority, randomized controlled trial will enroll 720 patients across 12 urological centers. Patients will be randomized to either f-URS with S-UAS or mini-PCNL. Outcomes include immediate and 3-month SFR, operative time, hospital stay, further interventions, complications, and quality of life.
Results: Data will be analyzed using intention-to-treat and per-protocol approaches, with statistical analyses performed using SPSS software.
Conclusion: This study will provide high-level evidence on the effectiveness of f-URS with S-UAS compared to mini-PCNL for medium-sized renal stones.
Detailed Description
- Background
According to the EAU and AUA guidelines, percutaneous nephrolithomy (PCNL) remains the first-line treatment for renal stones larger than 2 cm. In recent years, advancement in flexible ureteroscopic technology, such as the emergence of smaller disposable flexible ureteroscopes and suction techniques, have increased the efficiency of flexible ureteroscopy and expanded its indications.
The tip bendable suction ureteral access sheath (S-UAS) is a novel UAS characterized by excellent flexibility and bendability at the tip, enabling passive bending (angle >90°) in sync with the bending of flexible ureteroscope. It can be connected to a vacuum suction device. Initial studies suggest that S-UAS can significantly improve stone-free rates (SFR) and reduce the complication rates. Given the significant improvements in the effectiveness of flexible ureteroscopy (f-URS) with S-UAS, several studies report favorable outcomes in managing renal stones ≥2cm using flexible ureteroscopy. However, high-level evidence is still lacking to determine whether flexible ureteroscopy with S-UAS can achieve outcomes comparable to PCNL for medium-sized stones (2-3cm).
The objective of the current study is to assess the clinical outcomes of f-URS with S-UAS and mini-PCNL in the treatment of 2-3 cm renal stones, aiming to evaluate the suitability of f-URS for these patients. 2. Study objectives
The aim of this study is to determine whether f-URS with S-UAS is non-inferior to mini-PCNL in terms of surgical efficiency for 2-3 cm renal stones. An initial pilot phase will be included to assess the feasibility of recruitment and the appropriateness of eligibility criteria and outcome measures. The research question to be addressed is: does f-URS with S-UAS result in non-inferior stone-free rates compared to mini-PCNL? The secondary objective is to compare the complication rates, surgical time, and hospitalization time. 3. Methods and Design
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Treatment
- Masking
- Triple (Care Provider, Investigator, Outcomes Assessor)
Masking Description
Patients and surgeons cannot be blinded to the allocated trial arm due to the differing nature of the interventions. However, the radiologists assessing the post-operative imaging (CT scans) will be blinded to the intervention. The postoperative clinical assessment will be performed by investigators who are blinded to the surgical procedures and had not been involved in the surgeries. We will perform blinded statistical analyses, in which the individual performing the analyses in unaware the group belonging. The code for group assignment will not be broken until the analyses and interpretation have been completed.
Eligibility Criteria
- Ages
- 18 Years to — (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •Adults aged ≥ 18 years;
- •American Society of Anesthesiology score 1-3;
- •Renal stones diameter of 2-3 cm confirmed by non contrast-CT;
- •Capable of giving written informed consent, including adherence to the requirements of the trial.
Exclusion Criteria
- •Patients with abnormal urinary tract anatomy (such as horseshoe kidney or ileal conduit);
- •Patients with uncontrolled urinary tract infection;
- •Patients with health or other factors that are absolute contraindications to f-URS or mini-PCNL;
- •Patients unable to understand or complete trial documentation.
Outcomes
Primary Outcomes
Immediately stone-free rate (SFR)
Time Frame: Up to 72 hours.
No residual stone visualized under endoscopy and no residual stone or stone fragments less than 2 mm on low dose CT scan with a 2-mm section thickness within postoperative 72 hours are defined as stone free.
Secondary Outcomes
- Final SFR(3 months.)
- Duration of hospital stay(Up to 3 months.)
- Complications(Up to 3 months.)
- Operative time(through operation completion, an average of 1 hour)
- Improvement of Quality of Life Score(Up to 3 months.)
- Further interventions (Second-look PCNL or RIRS or SWL)(Up to 3 months.)
Investigators
Guohua Zeng
Vice president
The First Affiliated Hospital of Guangzhou Medical University