Sample size The sample size was determined based on an expected mean IPSS of 5.8 ± 2.6 at 1-year followup. The investigators considered a change of deference of IPSS ≤ 2 as an accepted equivalence between the two groups. The sample size was calculated to be at least 21 patients in each group with α=0.05, β=0.80 and a desired statistical power level of 80%. Considering the possibility of patients drop out or lost to followup, 40 patients will be enrolled in each arm. All measurement data will be presented as mean ± standard deviation.