Table 4.

Univariate Cox Proportional Hazard analysis of clinical, biopsy and imaging variables for the prediction of treatment failure in 262 patients with 35 treatment failures. HR = Hazards ratio. REF indicates the reference category to which the other categories are compared. For the continuous variables, the Hazards ratio indicates the percentage increase in the chance of a treatment failure event for a unit increase in the variable. For example, a 1.07 HR for age at diagnosis indicates that the chance of treatment failure increases by 7% for every year of increase in age. For the categorized variables, the HR indicates the percentage increase in the chance of TF compared to the reference category. All variables were significant (p < 0.05-p < 0.0001).

Variable type	Variable	Category	N	HR	[95% CI]
Clinical	Age at Diagnosis			1.07	[1.01–1.13]
	Pre-treatment PSA			1.09	[1.03–1.15]
	Clinical Stage	T1–T2	244	REF
		T3–T4	18	8.17	[3.99–16.75]
	Biopsy Gleason Score	≤ 3+4	227	REF
		> 3+4	35	8.13	[4.18–15.81]
	NCCN-based clinical risk score (CRS)	low	132	REF
		intermediate	102	2.51	[0.99–6.37]
		high	28	15.36	[6.29–37.48]
Biopsy Core	# negative cores (NNC)			0.86	[0.78–0.95]
Data	# positive cores (NPC)			1.28	[1.16–1.41]
	% of cores positive			1.03	[1.02–1.04]
MRI	MRI Stage
		1–3	235	REF
		4–7	27	6.57	[3.25–13.26]
MRSI	# of index lesion voxels (NILV)			1.08	[1.06–1.11]
	# of high grade (HG) voxels (NHGV)			1.14	[1.08–1.21]
	# of undetectable polyamine voxels (NUPV)			1.11	[1.07–1.16]