At 12 months , interstitial ( 125 ) I implantation had induced a significant decrease in prostate volume ( 28.3 11.1-20 .5 8.1 g in the silodosin group and 26.1 9.7-17 .7 4.9 g in the controls ) and the prostate-specific antigen level ( 7.1 3.6-1 .4 1.7 ng/mL in the silodosin group and 8.1 4.3-1 .3 1.2 ng/mL in the controls ) .