Authors' objectives: Renal tract stone disease is common. The three intervention options are shockwave lithotripsy, flexible ureteroscopic stone treatment and keyhole surgery. To determine which of shockwave lithotripsy, flexible ureteroscopic stone treatment and keyhole surgery offer the best outcomes in terms of health and quality of life, clinical effectiveness and cost-effectiveness for people with lower pole kidney stones. Renal tract stone disease is very common, with a lifetime prevalence of approximately 10% across the world. It mainly affects adults of working age, and the incidence has been increasing over recent decades. Approximately 50% of people with renal tract stones will experience symptoms, typically kidney pain, and about 25% of patients with stones will require active treatment. Many of these stones occur in the lower pole of the kidney and the three standard active intervention options are extracorporeal shockwave lithotripsy (ESWL), flexible ureteroscopic stone treatment (FURS) and keyhole surgery [percutaneous nephrolithotomy (PCNL)]. The aim of the PUrE study was to determine which of ESWL, FURS and PCNL offer the best treatment outcomes in terms of health status, clinical-effectiveness, and cost-effectiveness for people with lower pole kidney stones seeking treatment within the UK NHS.

Authors' results and conclusions: RCT1: A total of 461 participants were randomised: 231 to flexible ureteroscopic stone treatment; and 230 to shockwave lithotripsy. RCT2: A total of 159 participants were randomised: 73 to flexible ureteroscopic stone treatment; and 86 to keyhole surgery. The PUrE study found in RCT1 that shockwave lithotripsy was more cost-effective than flexible ureteroscopic stone treatment, with no meaningful difference in patient health status even though complete stone-free rates were higher with flexible ureteroscopic stone treatment. In RCT2, keyhole surgery was more cost-effective than flexible ureteroscopic stone treatment on a micro-costing basis, which better reflects treatment cost differences to the NHS. Keyhole surgery was marginally beneficial for health status with higher complete stone-free rates. Main outcome RCT1: The mean health status AUC was 0.807 [standard deviation (SD) 0.205] in the FURS group (n = 164) and 0.826 (SD 0.207) in the ESWL group (n = 188). The adjusted effect estimate was 0.024 [confidence interval (CI) −0.004 to 0.053] and this was not significant (p = 0.097). Complete stone clearance was higher with FURS (72%) than with ESWL (36%). RCT2: The mean health status AUC was 0.794 (SD 0.198) in the FURS group (n = 57) and was 0.818 (SD 0.217) in the PCNL group (n = 63). The adjusted effect estimate was −0.07 (CI −0.11 to −0.02; p = 0.006). Complete stone clearance was higher with PCNL (71%) than with FURS (48%). The PUrE study shows in RCT1 that ESWL for lower renal pole stones under 10 mm was more cost-effective than FURS, and there was no meaningful difference in patient health status. Stone-free rates (SFRs) were higher, however with FURS. From an overall NHS perspective, the costs savings of treating all patients with these stones with ESWL would be substantial. In RCT2, for larger stones 10–25 mm, PCNL was more cost-effective than FURS when using micro-costing to cost the interventions. Health status was marginally beneficial and SFRs were higher with PCNL.

Authors' recommendations: What effect will suction devices, improvements in laser technology, and intraoperative pressure monitoring have on postoperative pain, QoL, SFRs, complications, and costs of FURS? What is the effect of minaturisation of PCNL on postoperative pain, length of stay, complications, SFRs, and costs? What is the clinical and cost-effectiveness of full metabolic assessment compared with standard advice alone, in people who have undergone treatment for LPSs?

Authors' methods: The PUrE study comprised two pragmatic multicentre, open-label, superiority randomised controlled trials: RCT1 for lower pole stones ≤ 10 mm and RCT2 for lower pole stones > 10 and ≤ 25 mm. National Health Service Urology departments. Adults presenting with lower pole renal stones, able to undergo any of the treatments and complete trial procedures. The primary outcome measure was health status ‘area under the curve’, measured weekly to 12 weeks post intervention with the EuroQol-5 Dimensions, five-level version. The primary economic outcome was the incremental cost per quality-adjusted life-year gained at 12 months from randomisation. Blinding of participants and healthcare providers was not possible. There were differential waiting times between interventions in RCT1; however, adjusting for this gave similar treatment effect estimates. Design Two pragmatic multicentre, patient-randomised, open-label superiority randomised controlled trials (RCTs): the first (RCT1) for lower pole stones (LPSs) ≤ 10 mm in maximum dimension and the second (RCT2) for LPSs > 10 and ≤ 25 mm. National Health Service secondary care units across the UK, with a high volume of patients presenting with LPSs, and able to deliver all active treatments. Adults (16 years or over) with lower pole renal stones judged to require active treatment. Clinical: (1) Health status area under the curve (AUC) measured weekly to 12 weeks post intervention using the EuroQol-5 Dimensions, five-level version (EQ-5D-5L) and (2) stone clearance at 12 weeks. Economic: Incremental cost per quality-adjusted life-years (QALYs) gained at 12-months from randomisation. QALYs are based on the responses to the EQ-5D-5L.

Project Status: Completed

URL for project: https://www.journalslibrary.nihr.ac.uk/programmes/hta/13/152/02

Year Published: 2025

URL for published report: https://www.journalslibrary.nihr.ac.uk/hta/WFRE6844

URL for additional information: English

English language abstract: An English language summary is available

Publication Type: Full HTA

Country: England, United Kingdom

DOI: 10.3310/WFRE6844

Organisation Name: NIHR Health Technology Assessment programme

Contact Address: NIHR Journals Library, National Institute for Health and Care Research, Evaluation, Trials and Studies Coordinating Centre, Alpha House, University of Southampton Science Park, Southampton SO16 7NS, UK

Contact Name: journals.library@nihr.ac.uk

Contact Email: journals.library@nihr.ac.uk