PCNL vs RIRS in management of stones in calyceal diverticulum: outcomes from a global multicentre match paired study...

Calyceal diverticulum (CD) is the outpouching of a calyx into the renal parenchyma, connected by an infundibulum. Often associated with recurrent stones, common surgical options include percutaneous nephrolithotomy (PCNL) or retrograde intrarenal surgery (RIRS). We aim to present the real-world practises and outcomes comparing both approaches and the technical choices made.

Retrospective data including 313 patients from 11 countries were evaluated. One hundred and twenty-seven underwent mini-PCNL and one hundred and eighty-six underwent RIRS. Patient demographics, perioperative parameters, and outcomes were analysed using either T test or Mann-Whitney U test. Categorical data between groups were analysed using the Chi-squared test. Propensity score matching (PSM) was performed matching for baseline characteristics. Subgroup analyses for anomalous/malrotated kidneys and difficult diverticulum access were performed.

After PSM, 123 patients in each arm were included, with similar outcomes for stone-free rate (SFR) and complications (p < 0.001). Hospitalisation was significantly longer in PCNL. Re-intervention rate for residual fragments (any fragment > 4 mm) was similar. RIRS was the preferred re-intervention for both groups. Intraoperative bleeding was significantly higher in PCNL (p < 0.032) but none required transfusion. Two patients with malrotated anatomy in RIRS group required transfusion. Lower pole presented most difficult access for both groups, and SFR was significantly higher in difficult CD accessed by RIRS (p < 0.031). Laser infundibulotomy was preferred for improving diverticular access in both. Fulguration post-intervention was not practised.

The crux lies in identification of the opening and safe access. Urologists may consider a step-up personalised approach with a view of endoscopic combined approach where required.