Development of a nomogram for predicting a positive repeat prostate biopsy

Table 1 Clinical and pathological characteristics n (%)

Predictor variables		No cancer	Cancer	P value
		n = 675	n = 132
Digital rectal ex- amination	Negative	642 (95.1)	122 (92.4)	0.209
	Positive	33 (4.9)	10 (7.6)
TRUS	Negative	603 (89.3)	108 (81.8)	0.015
	Positive	72 (10.7)	24 (18.2)
HGPIN in previous biopsy	Negative	648 (96)	121 (91.7)	0.032
	Positive	27 (4)	11 (8.3)
ASAP in previous biopsy	Negative	627 (92.9)	116 (87.9)	0.051
	Positive	48 (7.1)	16 (12.1)
Age, yr	Mean	67	68.8	0.008
	SD	7.3	6.3
No. of previous biopsy sessions	Mean	1.7	1.7	0.894
	SD	1	1.1
No. of biopsy cores	Mean	11.3	11.9	0.006
	SD	2.4	2.5
Cumulative No. of cores	Mean	16.1	15.8	0.791
	SD	12.3	11.4
Months from the initial biopsy	Mean	26.8	25.7	0.576
	SD	21.0	22.7
Months from the previous biopsy	Mean	16.9	15.7	0.353
	SD	13.7	13.6
PSA slope (ng/mL per year)	Mean	1.2	1.3	0.824
	SD	5.7	13.2
PSA (ng/mL)	Mean	9.8	11.6	0.011
	SD	6.7	9.8
Prostate volume (cc)	Mean	53.0	43.8	< 0.001
	SD	25.8	27.2
TZ prostate volume (cc)	Mean	30.2	21.2	< 0.001
	SD	20.4	17.9
PSA density (ng/mL per cc)	Mean	0.2	0.3	< 0.001
	SD	0.2	0.4
PSA TZ density (ng/mL per cc)	Mean	0.4	0.8	< 0.001
	SD	0.4	0.9

TRUS: Transrectal ultrasonography; HGPIN: High grade prostatic intraepithelial neoplasia; ASAP: Atypical small acinar proliferation; TZ: Transitional zone.