Long-term follow-up after primary extracorporeal shockwave lithotripsy monotherapy of staghorn calculi: results after more than 6 years.

Objective: We retrospectively investigated 58 patients suffering from 60 staghorn calculi, who were treated with primary extracorporeal shockwave lithotripsy (ESWL) monotherapy, in order to determine long-term results and the fate of the residual stones.

Material and methods: Mean follow-up was 72.4 months. There were 49 partial staghorn calculi (C4) and 11 complete C5 stones according to Rocco's classification. The mean number of ESWL sessions needed for disintegration was 3.6. The mean amount of shockwaves was 10,244. ESWL monotherapy alone was performed in 26 staghorn calculi (43.3%). In treating the other 34 staghorn calculi 56 auxiliary procedures were necessary.

Results: At discharge 28.3% of the patients were free of stones. Fifty-five percent had small remnant particles (< 4 mm) and 16.7% had rest-fragments (> 4 mm). After a mean follow-up period of 72.4 months 36 patients were free of stones (60%). Twenty-four patients still have residual stones. The fragments in 2 patients did not change in size, in 14 patients fragments became bigger and 8 patients had a real recurrence (13.3%).

Conclusions: Primary ESWL monotherapy of staghorn calculi is justified because of the comparable results with open surgery and percutaneous nephrolithotomy (PCNL). Prognostic good factors are small stone mass with most of the stone mass in the upper and middle calices, the absence of dilatation and the absence of anatomical anomalies.