Cumulative incidences of prostate cancer-specific mortality were 41 % ( 95 % CI 22-70 ) in the STAS group , 78 % ( 49-115 ) in the STAS plus zoledronic acid group , 74 % ( 46-110 ) in the ITAS group , and 43 % ( 23-73 ) in the ITAS plus zoledronic acid group .