RIRS with TFLLT shows similar stone-free rates to PNL for 20-30 mm kidney stones in adults

This randomized prospective study was conducted at the Urology Clinic of Atatürk University Research Hospital. The population consisted of 86 adults with a single kidney stone classified as Guy stone score 1. These stones were located in the renal pelvis, lower pole, or middle pole and measured between 20-30 mm. The sample was divided into 44 patients in the RIRS group and 42 patients in the PNL group. The study aimed to evaluate the efficacy and safety of RIRS performed with Thulium Fiber Laser Lithotripsy (TFLLT) compared to standard PNL.

The primary outcome measured was stone-free rates. Results indicated that stone-free rates were statistically similar between the two groups. The p-value for this comparison was 0.714. This suggests that the choice between RIRS and PNL does not significantly impact the likelihood of being stone-free at follow-up for stones in this size range. No specific absolute numbers for stone-free rates were reported in the provided data, but the statistical equivalence was established.

Secondary outcomes included operative time, hemoglobin decrease, hospital stay, postoperative complications, fluoroscopy time, postoperative pain, and analgesic consumption. Operative time was longer in the RIRS group compared to the PNL group. Conversely, hemoglobin decrease was significantly greater in the PNL group with a p-value less than 0.001. Similarly, hospital stay duration was longer in the PNL group with a p-value less than 0.001. The direction of these differences favored RIRS regarding blood loss and length of stay.

Postoperative complications showed no statistically significant difference between the groups with a p-value of 0.806. The study did not report specific adverse events, serious adverse events, discontinuations, or overall tolerability metrics. Data regarding fluoroscopy time, postoperative pain scores, and analgesic consumption were not detailed in the provided results. The absence of reported adverse event data limits the ability to fully assess the safety profile beyond the reported hemoglobin and complication statistics.

A key limitation noted is that further studies with larger patient series will contribute to the literature. This single-center study with 86 patients may limit the generalizability of the findings to broader populations. The lack of reported adverse events and specific pain metrics prevents a comprehensive safety comparison. The study design does not allow for causal conclusions regarding long-term outcomes or rare complications.

Clinically, RIRS with TFLLT may have the potential to be a safe and effective alternative to PNL for kidney stones measuring 20-30 mm. The shorter hospital stay and reduced hemoglobin loss with RIRS are relevant for patient recovery and resource utilization. However, the longer operative time for RIRS must be weighed against the benefits of less invasiveness. Practitioners should consider these trade-offs when selecting a procedure for patients with stones in the renal pelvis, lower pole, or middle pole.

Several questions remain unanswered. The lack of reported adverse events and specific pain data leaves gaps in the safety profile. Long-term stone recurrence rates were not addressed. The optimal laser settings or specific RIRS protocols for TFLLT were not detailed. Future research with larger cohorts is needed to validate these findings and provide more granular safety data. Until then, clinicians should interpret these results with caution regarding the equivalence of safety profiles.