Comparison of miniaturized percutaneous nephrolithotomy and flexible ureterorenoscopy for moderate size renal stones in elderly patients

Life expectancy has become longer, thus the number of elderly people who require treatment for nephrolithiasis has increased. We aimed to analyze the efficacy of flexible ureterorenoscopy (f-URS) and miniaturized percutaneous nephrolithotomy (mPNL) in the management of 10 and 30 mm renal stones in patients aged >60 years. In prospective non-randomized series, the data of patients who underwent f-URS or mPNL for kidney stones between July 2013 and July 2016 were analyzed. The procedure was accepted as successful if the patient was achieved complete stone clearance according to CT imaging between 1-3 months postoperatively. In total 60 patients and 58 patients were underwent f-URS and mPNL, respectively. The mean operation time, fluoroscopy time and hospitalization time were significantly shorter for the f-URS (p < 0.001, p < 0.001, p < 0.001, respectively). According to Clavien classification system, complication rates were not significantly different between the groups (p = 0.673). The stone-free rate was 81.7% for the f-URS group and 77.6% for the mPNL group after a single-session procedure (p = 0.747). Calcium oxalate monohydrate stones were the most common stone type in both groups. In multivariate analysis, multiple stones localization was only independent factor to predict complications. Our study had showed that both f-URS and mPNL are effective treatment modalities for 10-30-mm renal stones in elderly patients. Additionally, presence of stones in multiple location was the only predictive factor for complication development.