Table 2.

Cox hazard analysis of factors associated with biochemical recurrence-free survival

Models	Total cohort (univariate model)			Total cohort (multivariate model 1)a			PSM cohort (multivariate model 2)b
	HR	95% CI	P	HR	95% CI	P	HR	95% CI	P
PSM versus NSM	3.310	1.900–5.740	<0.0001	2.681	1.474–4.878	0.0012
Gleason pattern of PSM (vs NSM)
Gleason pattern <4	1.440	0.660–3.140	0.3640	1.212	0.522–2.813	0.6551	1.000		Reference
Gleason pattern ≥4	6.670	3.670–12.100	<0.0001	4.434	2.347–8.380	<0.0001	4.386	1.938–9.928	0.0004
Length of PSM (vs NSM)
<8 mm	2.310	1.110–4.840	0.0260	2.497	1.156–5.394	0.0198	1.000		Reference
≥8 mm	4.160	2.230–8.090	<0.0001	2.804	1.441–5.456	0.0024	1.236	0.536–2.854	0.6191
Number of PSMs (vs NSM)
1	2.670	1.390–5.140	0.0030	2.448	1.240–4.828	0.0098	1.000		Reference
≥2	4.250	2.230–8.090	<0.0001	3.056	1.471–6.347	0.0027	1.147	0.445–2.955	0.7767
Location of PSM (vs NSM)
Apex	3.660	1.990–6.730	<0.0001	3.861	1.919–7.768	0.0002	1.000		Reference
Base	5.210	2.370–11.420	<0.0001	1.826	0.742–4.491	0.1898	1.294	0.272–6.160	0.7464
Anterior	3.120	1.500–6.480	0.0020	2.727	1.162–6.400	0.0212	0.765	0.131–4.467	0.7663
Posterolateral	3.560	1.800–7.040	<0.0001	2.691	1.300–5.570	0.0076	0.908	0.158–5.219	0.9143

^aIn multivariate model 1, each variable was adjusted for initial PSA, pathologic Gleason score, and pathologic T stage; ^bIn multivariate model 2, all variables related to PSM were entered into the PSM cohort. CI: confidence interval; HR: hazard ratio; PSM: positive surgical margin; NSM: negative surgical margin; PSA: prostate-specific antigen