Risk Stratification after Biochemical Failure following Curative Treatment of Locally Advanced Prostate Cancer: Data from the TROG 96.01 Trial
Table 2
Performance of 24 candidate post-biochemical failure risk categorization schemes (BFRC)* in univariable competing risk models for prostate cancer-specific mortality (PCSM) after biochemical failure.
BFRC model
High risk†
Low risk†
Intermediate risk‡
BFRC model performance§
PSADT
TTBF
HR
(95% CI)
PSADT
TTBF
HR
HR
(95% CI)
c-Index
(95% CI)
Rank
value#
1
97
<3
<1
6.1
(3.8–9.8)
231
>9
>4
1
157
2.7
(1.8–4.3)
0.724
(0.685–0.763)
7
0.32
2
113
<3
<1.5
5.1
(3.3–7.7)
267
>6
>4
1
105
2.7
(1.8–4.2)
0.719
(0.678–0.760)
8
0.28
3
129
<3
<1.5
5.6
(3.5–9.0)
222
>9
>4
1
134
2.7
(1.7–4.3)
0.718
(0.679–0.757)
9
0.15
4
163
<3
<2
5.2
(3.2–8.5)
212
>9
>4
1
110
2.8
(1.6–4.7)
0.705
(0.668–0.743)
13
0.013
5
166
<3
<2
5.1
(3.2–8.3)
221
>12
>3
1
98
2.9
(1.7–4.9)
0.697
(0.658–0.736)
17
0.007
6
171
<3
<2
7.3
(3.9–13.7)
183
>12
>4
1
131
3.9
(2.1–7.5)
0.695
(0.657–0.733)
19
0.004
7
119
<4
<1
5.7
(3.7–8.8)
246
>9
>3
1
120
2.6
(1.7–4.2)
0.732
(0.695–0.769)
1#
—
8
119
<4
<1
7.0
(4.3–11.3)
225
>12
>3
1
141
3.1
(1.9–5.1)
0.730
(0.693–0.767)
2
0.70
9
120
<4
<1
8.2
(4.8–14.1)
208
>24
>3
1
157
3.5
(2.0–6.0)
0.729
(0.692–0.767)
3
0.68
10
188
<4
<2
8.1
(4.2–15.5)
180
>12
>4
1
117
3.7
(1.9–7.3)
0.705
(0.669–0.741)
14
0.019
11
196
<4
<2
7.4
(3.8–14.7)
163
>18
>4
1
126
2.9
(1.4–5.9)
0.697
(0.661–0.733)
16
0.005
12
196
<4
<2
8.0
(3.9–16.4)
159
>24
>4
1
130
3.1
(1.4–6.5)
0.697
(0.660–0.733)
18
0.005
13
150
<5
<1
7.6
(4.4–13.0)
201
>24
>3
1
134
3.4
(1.9–6.0)
0.727
(0.691–0.762)
4
0.55
14
149
<5
<1
5.2
(3.4–7.9)
239
>9
>3
1
97
2.5
(1.5–4.1)
0.726
(0.691–0.762)
5
0.41
15
149
<5
<1
6.3
(3.9–10.3)
218
>12
>3
1
118
3.1
(1.8–5.1)
0.726
(0.690–0.762)
6
0.45
16
201
<5
<2
8.4
(4.3–16.6)
173
>12
>4
1
111
3.9
(1.9–7.9)
0.700
(0.665–0.735)
15
0.007
17
209
<5
<2
7.8
(3.8–15.9)
156
>18
>4
1
120
3.0
(1.4–6.4)
0.693
(0.658–0.728)
20
0.002
18
209
<5
<2
8.5
(4.0–18.2)
152
>24
>4
1
124
3.2
(1.4–7.2)
0.693
(0.658–0.728)
21
0.002
19
141
<6
<1
5.0
(3.3–7.7)
235
>18
>2
1
109
2.4
(1.5–3.9)
0.714
(0.676–0.753)
10
0.18
20
184
<6
<1
6.8
(3.9–11.8)
190
>24
>3
1
111
2.7
(1.5–5.0)
0.713
(0.679–0.748)
11
0.07
21
140
<6
<1
4.7
(3.1–7.1)
242
>12
>2
1
103
2.4
(1.5–3.8)
0.712
(0.674–0.751)
12
0.12
22
220
<6
<2
7.7
(3.9–15.0)
167
>12
>4
1
98
3.3
(1.6–6.9)
0.691
(0.657–0.725)
22
0.001
23
228
<6
<2
7.0
(3.5–14.3)
150
>18
>4
1
107
2.4
(1.1–5.3)
0.685
(0.651–0.719)
23
<0.001
24
228
<6
<2
7.7
(3.6–16.4)
146
>24
>4
1
111
2.6
(1.1–6.0)
0.685
(0.651–0.719)
24
<0.001
PSA: prostate-specific antigen; BFRC: biochemical failure risk categorization; : number of patients; PSADT: PSA doubling time (months); TTBF: time from biochemical (Phoenix) failure (years); HR: hazard ratio; CI: confidence interval; c-index: Harrell’s concordance index.
*BFRC schemes presented include the best and worst three schemes for each high risk PSADT cutpoint from the 72 evaluable schemes. †Risk is defined by PSADT and/or TTBF ranges specified. ‡PSADT and TTBF ranges are intermediate between the high and low risk ranges. §Performance assessed by C-index, ranked highest (best) to lowest (worst). Performance against best BFRC compared using paired Student’s -test.
#The best BFRC scheme. ¶A
-value
for the paired Student’s t-test indicates that the BFRC model is significantly worse (less predictive) than the best BRFC model.
