Table 2.

Failure-free survival based on patient, tumor and treatment characteristics^#.

Characteristics	N (events)	Univariate analysis			Multivariate analysis*
		p-value	HR	95% CI	p-value	HR	95% CI
Pre-RT PSA (ng/ml)
<0.5	81 (26)		1.00			1.00
≥0.5	115 (59)	0.006	1.92	1.21 – 3.05	0.021	1.84	1.09–3.08
Clinical T Stage
T1–T2a	55 (14)		1.00			1.00
T2b–T2c	47 (24)	0.095	1.76	0.91 – 3.42	0.077	1.83	0.94–3.58
T3–T4	88 (46)	0.40	1.30	0.71 – 2.38	0.30	1.39	0.74–2.60
Gleason Score
5–6	15 (6)		1.00
7	57 (25)	0.33	1.56	0.64 – 3.83
8–10	124 (54)	0.33	1.53	0.66 – 3.57
iPSA (ng/ml)
≤10	60 (15)		1.00			1.00
10.1–20	41 (20)	0.068	1.87	0.95 – 3.65	0.51	1.28	0.61–2.68
>20	95 (50)	0.008	2.18	1.22 – 3.89	0.19	1.54	0.80–2.96
iPSA (ng/ml)	196 (85)	0.17	1.00	0.99 – 1.01
Duration of neoadjuvant ADT (mo)	194 (85)	0.14	1.09	0.97 – 1.22	0.087	1.10	0.99–1.23
Total duration of ADT (yrs)
<1	39 (11)		1.00			1.00
1–2	60 (28)	0.016	2.37	1.17 – 4.78	0.013	2.51	1.21–5.20
>2	95 (46)	0.15	1.62	0.84 – 3.14	0.19	1.58	0.79–3.16
Type of neoadjuvant ADT
LH/RH monotherapy/orchiectomy	137 (65)
Total androgen blockade	59 (20)	0.40	0.81	0.49 – 1.34
Age	196 (85)	0.11	0.98	0.95 – 1.01	0.49	0.99	0.96–1.02
Race
Others	169 (73)		1.00
African-American	27 (12)	0.59	1.19	0.64 – 2.19
Radiation dose (Gy)	196 (85)	0.40	0.97	0.91 – 1.04

Abbreviations: pre-RT PSA = pre- radiation therapy prostate specific antigen, iPSA = pre-treatment prostate specific antigen, ADT = androgen deprivation therapy, HR = hazard ration, 95% CI = 95% confidence interval.

^#Because death is included as an event in the definition of FFS, Cox proportional hazards regression was performed to model the impact of patient, tumor and treatment characteristics on the FFS.

^*After univariate analyses, factors that reached a p-value of 0.25 or less were included in a multivariate model.