Donaldson JF et al, 2015: Systematic Review and Meta-analysis of the Clinical Effectiveness of Shock Wave Lithotripsy, Retrograde Intrarenal Surgery, and Percutaneous Nephrolithotomy for Lower-pole Renal Stones.
Donaldson JF, Lardas M, Scrimgeour D, Stewart F, MacLennan S, Lam TB, McClinton S
Department of Urology, Aberdeen Royal Infirmary, Aberdeen, UK
Academic Urology Unit, University of Aberdeen, Aberdeen, UK
The prevalence of urolithiasis is increasing. Lower-pole stones (LPS) are the most common renal calculi and the most likely to require treatment. A systematic review comparing shock wave lithotripsy (SWL), retrograde intrarenal surgery (RIRS), and percutaneous nephrolithotomy (PNL) in the treatment of ≤20 mm LPS in adults was performed. Comprehensive searches revealed 2741 records; 7 randomised controlled trials (RCTs) recruiting 691 patients were included. Meta-analyses for stone-free rate (SFR) at ≤3 mo favoured PNL over SWL (risk ratio [RR]: 2.04; 95% confidence interval [CI], 1.50-2.77) and RIRS over SWL (RR: 1.31; 95% CI, 1.08-1.59). Stone size subgroup analyses revealed PNL and RIRS were considerably more effective than SWL for >10 mm stones, but the magnitude of benefit
was markedly less for ≤10 mm stones. The quality of evidence (Grading of Recommendations Assessment, Development, and Evaluation [GRADE]) for SFR was moderate for these comparisons. The median SFR from reported RCTs suggests PNL is more effective than RIRS. The findings regarding other outcomes were inconclusive because of limited and inconsistent data. Well-designed, prospective, comparative studies that measure these outcomes using standardised definitions are required, particularly for the direct comparison of PNL and RIRS. This systematic review, which used Cochrane methodology and GRADE quality-of-evidence assessment, provides the first level 1a evidence for the management of LPS. PATIENT SUMMARY: We thoroughly examined the literature to compare the benefits and harms of the
different ways of treating kidney stones located at the lower pole. PNL and RIRS were superior to SWL in clearing the stones within 3 mo, but we were unable to make any conclusions regarding other outcomes. More data is required from reliable studies before firm
recommendations can be made.
Eur Urol. 2014 Oct 23. pii: S0302-2838(14)01005-7. doi: 10.1016/j.eururo.2014.09.054. [Epub ahead of print]
This meta-analysis demonstrates the well-known outcome that SWL of lower calyx stones is associated with a lower stone-free rate than that seen with endoscopic procedures. This conclusion was based on analysis of seven RCTs in which studies at least the endourological procedures had been carried out by experts.
The principles for allowing repeated SWL sessions most certainly varied considerably between different centres inasmuch as the reported re-treatment rates varied between 8.6 and 67.1%. The complications varied between 5.7 and 48.6%. Different criteria for complications probably partly explain this wide range, but it can be assumed that different strategies for SWL treatment and patient preparation had been applied. The higher complication rates in SWL-treated patients compared with complications associated with PNL and RIRS are surprising. There is, unfortunately, no information on auxiliary procedures and type of anaesthesia and it was accordingly not possible to calculate stone treatment index in the various groups.
Although repeated RCTs might shed some additional light on differences between invasive and non-invasive procedures for active removal of lower calyx stones, it would indeed be of greater interest to learn about the long-term course of lower calyx residuals and how these patients best should be treated.