Table 2.
Baseline characteristics for men diagnosed as having metastasis after treatment, low risk at cancer diagnosis
| Characteristic | Overall cohort | Propensity-matched cohort | ||||
|---|---|---|---|---|---|---|
| Irradiation, no. (%) (n = 708) |
Radical prostatectomy, no. (%) (n = 178) |
SD* | Irradiation, no. (%) (n = 171) |
Radical prostatectomy, no. (%) (n = 171) |
SD* | |
| Age, yr | ||||||
| 66–69 | 169 ( 23.9) | 78 ( 43.8) | 0.4313 | 70 ( 40.9) | 71 ( 41.5) | 0.0119 |
| 70–74 | 282 ( 39.8) | 89 ( 50.0) | 0.2055 | 90 ( 52.6) | 89 ( 52.1) | 0.0117 |
| 75–79 | 209 ( 29.5) | 10 ( 5.6) | 0.6615 | 10 ( 5.9) | 10 ( 5.9) | 0 |
| ≥80 | 48 ( 6.8) | 1 ( 0.6) | 0.3353 | 1 ( 0.6) | 1 ( 0.6) | 0 |
| Race | ||||||
| White | 590 ( 83.3) | 158 ( 88.8) | 0.1572 | 141 ( 82.5) | 152 ( 88.9) | 0.1844 |
| Black | 65 ( 9.2) | 11 ( 6.2) | 0.1129 | 17 ( 9.9) | 10 ( 5.9) | 0.1522 |
| Others | 53 ( 7.5) | 9 ( 5.1) | 0.1003 | 13 ( 7.6) | 9 ( 5.3) | 0.0955 |
| Year of diagnosis | ||||||
| 2000 or earlier | 409 ( 57.8) | 143 ( 80.3) | 0.5034 | 136 ( 79.5) | 136 ( 79.5) | 0 |
| 2001 or later | 299 ( 42.2) | 35 ( 19.7) | 0.5034 | 35 ( 20.5) | 35 ( 20.5) | 0 |
| Region | ||||||
| North central | 179 ( 25.3) | 41 ( 23.0) | 0.0526 | 41 ( 23.9) | 41 ( 23.9) | 0 |
| Northeast | 166 ( 23.5) | 13 ( 7.3) | 0.4592 | 13 ( 7.6) | 13 ( 7.6) | 0 |
| South | 99 ( 13.9) | 12 ( 6.7) | 0.2393 | 12 ( 7.0) | 12 ( 7.0) | 0 |
| West | 264 ( 37.3) | 112 ( 62.9) | 0.5304 | 105 ( 61.4) | 105 ( 61.4) | 0 |
| Comorbidity | ||||||
| 0 | 542 ( 76.6) | 160 ( 89.9) | 0.3626 | 153 ( 89.5) | 153 ( 89.5) | 0 |
| ≥1 | 166 ( 23.5) | 18 ( 10.1) | 0.3626 | 18 ( 10.5) | 18 ( 10.5) | 0 |
| Cancer stage | ||||||
| T1 | 462 (65.3) | 128 ( 71.9) | 0.1438 | 122 ( 71.4) | 121 ( 70.8) | 0.0129 |
| T2a | 246 (34.8) | 50 ( 28.1) | 0.1438 | 49 ( 28.7) | 50 ( 29.2) | 0.0129 |
| ≥T2b | NA | NA | ||||
| Cancer grade Well differentiated |
42 ( 5.9) | 19 ( 10.7) | 0.1725 | 20 ( 11.7) | 19 ( 11.1) | 0.0184 |
| Moderately differentiated State buy-in |
666 ( 94.1) | 159 ( 89.3) | 0.1725 | 151 ( 88.3) | 152 ( 88.9) | 0.0184 |
| No | 651 (91.9) | 168 (94.4) | 0.0965 | 157 (91.8) | 161 ( 94.2) | 0.0917 |
| Yes | 57 (8.1) | 10 (5.6) | 0.0965 | 14 ( 8.2) | 10 ( 5.9) | 0.0917 |
SD = standardized difference.
*
SD = |P1 - P2| / square root of (P1[1 – P1] + P2[1 – P2] / 2). SDs are the same for all categorical variables with two levels.
Cancer grade: The Surveillance Epidemiology and End Results registry used a system of describing tumors as well differentiated, moderately differentiated, and poorly differentiated based on a Gleason score of 2–4, 5–7, and 8–10, respectively, before 2003. Starting in 2003, code 7 was reclassified from moderately differentiated to poorly differentiated.