Kidney StonesMIMIC-PCNLNCT07697677
Modified Mini-PCNL Versus Standard PCNL for Complex Kidney Stones
A study testing 20 Fr Modified Mini Percutaneous Nephrolithotomy and 24 Fr Standard Percutaneous Nephrolithotomy in people with Kidney Stones and Complex Renal Calculi, run by The First Affiliated Hospital of Guangzhou Medical University at 1 site in China.
Trial 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. Read more about this study
- Who is it for?
- Ages 18 to 70 years
- Conditions the study is for
- Kidney Stones, Complex Renal Calculi
- What is being tested?
- 20 Fr Modified Mini Percutaneous Nephrolithotomy and 24 Fr Standard Percutaneous Nephrolithotomy
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 1,380 participants
- Where
- 1 siteChina
- Study dates
- 15 Jul 2026to 14 Sep 2027
- Phase
- Interventional
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 70 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- 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.
Who cannot join
- 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.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
China1 site, 1 recruiting
- Recruiting
The First Affiliated Hospital of Guangzhou Medical University
Guangzhou, Guangdong, 510120
Yongda Liu, +020-83062923, 13719007083@163.com
About this study
Official title: Modified Mini Percutaneous Nephrolithotomy Versus Standard Percutaneous Nephrolithotomy for the Treatment of Complex Renal Calculi: A Multicenter Randomized Controlled Trial
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.
- Conditions
- Kidney Stones, Complex Renal Calculi
- Being tested
- 20 Fr Modified Mini Percutaneous Nephrolithotomy, 24 Fr Standard Percutaneous Nephrolithotomy
- Keywords
- Percutaneous Nephrolithotomy, Mini-PCNL, Standard PCNL, Modified Mini-PCNL, Complex Renal Stones, Stone-Free Rate, Randomized Controlled Trial
- Medical subject headings
- Kidney Calculi
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
20 Fr Modified Mini Percutaneous NephrolithotomyProcedure or surgery
Also called Modified Mini-PCNL, Modified mPNL, 20 Fr Modified Mini-PCNL
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.
24 Fr Standard Percutaneous NephrolithotomyProcedure or surgery
Also called Standard PCNL, sPNL, 24 Fr Standard PCNL
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.
| Study group | Role | What they receive |
|---|---|---|
| Modified Mini-PCNL | Experimental | Participants randomized to this arm will undergo 20 Fr modified mini percutaneous nephrolithotomy using the F17 Hawk nephroscope for the treatment of complex renal stones. Receives: Procedure: 20 Fr Modified Mini Percutaneous Nephrolithotomy |
| Standard PCNL | Active comparator | Participants randomized to this arm will undergo 24 Fr standard percutaneous nephrolithotomy using the F20.8 Wolf nephroscope for the treatment of complex renal stones. Receives: Procedure: 24 Fr Standard Percutaneous Nephrolithotomy |
What is being measured
The primary outcome is the main question the study is designed to answer.
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.
Measured: Within 72 hours after surgery
Secondary outcomes (2)
Stone-Free Rate at 3 Months
Proportion of participants who achieve stone-free status at 3-month follow-up according to low-dose noncontrast CT.
Measured: 3 months after surgery
Length of Hospital Stay
Number of days from the day of surgery to the day of hospital discharge, rounded to the nearest whole day.
Measured: From surgery to hospital discharge, assessed up to 30 days after surgery
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted13 Jul 2026
- Study start15 Jul 2026 (estimated)
- Primary completion14 Jul 2027 (estimated)
- Study completion14 Sep 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Kidney StonesStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind
- Who is masked
- Outcomes assessor
- Enrolment
- 1,380 participants (estimated)
Sponsor and investigators
- Lead sponsor
- The First Affiliated Hospital of Guangzhou Medical University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Yongda Liu, The First Affiliated Hospital of Guangzhou Medical University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07697677
- Sponsor's protocol ID
- ES-2025-285-02
- Other IDs
- GMUCR2025-01006
- Acronym
- MIMIC-PCNL
- Status last verified
- Jul 2026
- First submitted
- 7 Jul 2026
- Last updated
- 13 Jul 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Publications
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.
PubMed 32994063