Modified Mini-PCNL Versus Standard PCNL for Complex Kidney Stones
MIMIC-PCNL
Modified Mini Percutaneous Nephrolithotomy Versus Standard Percutaneous Nephrolithotomy for the Treatment of Complex Renal Calculi: A Multicenter Randomized Controlled Trial
2 other identifiers
interventional
1,380
1 country
1
Brief Summary
Kidney stones that are large or complex are often treated with percutaneous nephrolithotomy, also called PCNL. Standard PCNL uses a larger access tract and is effective for removing complex kidney stones, but it may be associated with more bleeding, pain, and recovery burden. Modified mini-PCNL uses a smaller access tract and may reduce surgical trauma while maintaining a similar stone clearance rate. This multicenter randomized trial will compare modified mini-PCNL using a 20 Fr access sheath with standard PCNL using a 24 Fr access sheath in adults with complex renal stones. About 1,380 participants from 8 urology centers will be randomly assigned to receive one of the two procedures. The main purpose of the study is to determine whether modified mini-PCNL is not worse than standard PCNL in achieving stone-free status shortly after surgery. Stone-free status will be assessed by low-dose noncontrast CT within 72 hours after surgery. The study will also compare stone-free status at 3 months, complications, operation time, length of hospital stay, need for additional procedures, and quality of life.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for not_applicable
Started Jul 2026
1 active site
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
July 7, 2026
CompletedFirst Posted
Study publicly available on registry
July 13, 2026
CompletedStudy Start
First participant enrolled
July 15, 2026
CompletedPrimary Completion
Last participant's last visit for primary outcome
July 14, 2027
ExpectedStudy Completion
Last participant's last visit for all outcomes
September 14, 2027
July 13, 2026
July 1, 2026
12 months
July 7, 2026
July 7, 2026
Conditions
Keywords
Outcome Measures
Primary Outcomes (1)
Immediate Stone-Free Rate
Proportion of participants who achieve stone-free status after surgery. Stone-free status is defined as no residual stone visualized under endoscopy and no residual stone fragments, or residual fragments ≤2 mm, on low-dose noncontrast CT with 2-mm slice thickness.
Within 72 hours after surgery
Secondary Outcomes (2)
Stone-Free Rate at 3 Months
3 months after surgery
Length of Hospital Stay
From surgery to hospital discharge, assessed up to 30 days after surgery
Study Arms (2)
Modified Mini-PCNL
EXPERIMENTALParticipants randomized to this arm will undergo 20 Fr modified mini percutaneous nephrolithotomy using the F17 Hawk nephroscope for the treatment of complex renal stones.
Standard PCNL
ACTIVE COMPARATORParticipants randomized to this arm will undergo 24 Fr standard percutaneous nephrolithotomy using the F20.8 Wolf nephroscope for the treatment of complex renal stones.
Interventions
Standard percutaneous nephrolithotomy performed with a 24 Fr access sheath and F20.8 Wolf nephroscope. Stone fragmentation may be performed using pneumatic lithotripsy, Ho:YAG laser, or thulium fiber laser according to the standardized surgical protocol.
Modified mini percutaneous nephrolithotomy performed with a 20 Fr access sheath and F17 Hawk nephroscope. Stone fragmentation may be performed using pneumatic lithotripsy, Ho:YAG laser, or thulium fiber laser according to the standardized surgical protocol.
Eligibility Criteria
You may qualify if:
- Adults aged ≥18 years.
- Serum creatinine ≤133 μmol/L.
- American Society of Anesthesiologists (ASA) physical status classification I-III.
- S.T.O.N.E. score ≥8.
- Complex renal stones confirmed by noncontrast computed tomography, including stone surface area \>1500 mm², multiple calyceal stones, partial or complete staghorn calculi, or complex anatomical conditions.
- Patients who provide written informed consent and agree to undergo either modified mini-percutaneous nephrolithotomy or standard percutaneous nephrolithotomy.
You may not qualify if:
- Solitary kidney.
- Morbid obesity (body mass index ≥35 kg/m²).
- Previous renal transplantation or urinary diversion.
- Congenital abnormalities of the urinary tract.
- Pregnancy.
- Uncorrected coagulopathy.
- Active urinary tract infection.
Contact the study team to confirm eligibility.
Sponsors & Collaborators
Study Sites (1)
The First Affiliated Hospital of Guangzhou Medical University
Guangzhou, Guangdong, 510120, China
Related Publications (1)
Zeng G, Cai C, Duan X, Xu X, Mao H, Li X, Nie Y, Xie J, Li J, Lu J, Zou X, Mo J, Li C, Li J, Wang W, Yu Y, Fei X, Gu X, Chen J, Kong X, Pang J, Zhu W, Zhao Z, Wu W, Sun H, Liu Y, la Rosette J. Mini Percutaneous Nephrolithotomy Is a Noninferior Modality to Standard Percutaneous Nephrolithotomy for the Management of 20-40mm Renal Calculi: A Multicenter Randomized Controlled Trial. Eur Urol. 2021 Jan;79(1):114-121. doi: 10.1016/j.eururo.2020.09.026. Epub 2020 Sep 29.
PMID: 32994063RESULT
MeSH Terms
Conditions
Condition Hierarchy (Ancestors)
Central Study Contacts
Study Design
- Study Type
- interventional
- Phase
- not applicable
- Allocation
- RANDOMIZED
- Masking
- SINGLE
- Who Masked
- OUTCOMES ASSESSOR
- Purpose
- TREATMENT
- Intervention Model
- PARALLEL
- Sponsor Type
- OTHER
- Responsible Party
- PRINCIPAL INVESTIGATOR
- PI Title
- Professor and Director, Department of Urology
Study Record Dates
First Submitted
July 7, 2026
First Posted
July 13, 2026
Study Start
July 15, 2026
Primary Completion (Estimated)
July 14, 2027
Study Completion (Estimated)
September 14, 2027
Last Updated
July 13, 2026
Record last verified: 2026-07