Table 1.
Characteristics of the study population (N = 592)
| Indolent controls, N = 367 (N (%)) | Lethal cases, N = 225 (N (%)) | P‐value | |
|---|---|---|---|
| Age at diagnosis | |||
| Mean ± SD | 72.0 ± 6.6 | 74.8 ± 6.6 | <0.001 a |
| Calendar year of diagnosis | |||
| 1977‐1982 | 16 (4.4) | 13 (5.8) | 0.002 b |
| 1983‐1986 | 18 (4.9) | 4 (1.8) | |
| 1987‐1991 | 134 (36.5) | 113 (50.2) | |
| 1992‐1998 | 199 (54.2) | 95 (42.2) | |
| Tumor stage(1 missing) | |||
| T1a | 178 (48.6) | 56 (24.9) | <0.001 b |
| T1b | 188 (51.4) | 169 (75.1) | |
| Gleason score (1 missing) | |||
| ≤6 | 223 (60.9) | 45 (20.0) | <0.001 c |
| 3 + 4 | 81 (22.2) | 36 (16.0) | |
| 4 + 3 | 44 (12.0) | 44 (19.6) | |
| 8−10 | 18 (4.9) | 100 (44.4) | |
| Tumor percentage (55 missing) | |||
| ≤2 | 151 (44.9) | 37 (18.4) | <0.001 c |
| >2‐10 | 90 (26.8) | 50 (24.9) | |
| >10‐60 | 78 (23.2) | 79 (39.3) | |
| >60 | 17 (5.1) | 35 (17.4) |
SD, standard deviation.
a
t‐test.
b
χ 2‐ test.
c
χ 2‐test of trend.