Table 1.
Basic characteristics of patients and tumors
| Characteristics | PSM (n=108) | NSM (n=163) | Total (n=271) | P |
|---|---|---|---|---|
| Age (year), mean±s.d. | 63.8±7.3 | 65.6±6.7 | 64.9±7.0 | 0.039 |
| Initial PSA (ng ml−1), mean±s.d. | 9.2±7.5 | 7.1±4.8 | 7.9±6.0 | 0.013 |
| Body mass index (kg m−2), mean±s.d. | 24.3±3.3 | 24.7±2.6 | 24.5±2.9 | 0.315 |
| Hypertension, n (%) | 70 (64.8) | 89 (54.6) | 112 (41.3) | 0.122 |
| Diabetes mellitus, n (%) | 23 (21.3) | 29 (17.8) | 52 (19.2) | 0.576 |
| Charlson comorbidity index, n (%) | ||||
| 0 | 9 (8.3) | 18 (11.0) | 27 (10.0) | 0.720 |
| 1 | 62 (57.4) | 94 (57.7) | 156 (57.6) | |
| ≥2 | 37 (34.3) | 51 (31.3) | 88 (32.5) | |
| D’Amico risk, n (%) | ||||
| Low | 2 (1.9) | 15 (9.2) | 17 (6.3) | 0.032 |
| Intermediate | 14 (13.0) | 14 (8.6) | 28 (10.3) | |
| High | 92 (85.2) | 134 (82.2) | 226 (83.4) | |
| Clinical T2 stage, n (%) | 78 (72.2) | 133 (81.6) | 211 (77.9) | 0.095 |
| Extracapsular invasion on MRI, n (%) | 30 (27.8) | 24 (14.7) | 54 (19.9) | 0.144 |
| Seminal vesicle invasion on MRI, n (%) | 7 (6.5) | 12 (7.4) | 19 (7.0) | 0.454 |
| Clinical Gleason score, n (%) | ||||
| 6 | 30 (27.8) | 52 (31.9) | 82 (30.3) | 0.014 |
| 7 | 48 (44.4) | 81 (49.7) | 129 (47.6) | |
| 8 | 14 (13.0) | 25 (15.3) | 39 (14.4) | |
| ≥9 | 16 (14.8) | 5 (3.1) | 21 (7.7) | |
| Prostate volume on TRUS (ml), mean±s.d. | 34.1±10.1 | 34.9±14.5 | 34.6±12.9 | 0.675 |
| Membranous urethra length on MRI (mm), mean±s.d. | 12.0±4.0 | 12.1±2.8 | 12.1±3.4 | 0.919 |
| Percent of positive core (%), mean±s.d. | 57.8±33.5 | 51.4±37.0 | 53.9±35.7 | 0.155 |
| Maximal tumor percent of positive core (%), mean±s.d. | 51.3±31.0 | 39.1±25.3 | 44.0±28.3 | 0.001 |
| Prostate volume (ml), mean±s.d. | 29.4±9.7 | 31.0±13.1 | 30.4±11.8 | 0.264 |
| Tumor volume (ml), mean±s.d. | 6.6±7.7 | 2.6±2.6 | 4.2±5.6 | <0.001 |
| Pathologic Gleason score, n (%) | ||||
| 6 | 12 (11.9) | 36 (22.5) | 48 (18.4) | 0.015 |
| 7 | 70 (69.3) | 112 (70.0) | 182 (69.7) | |
| 8 | 4 (4.0) | 3 (1.9) | 7 (2.7) | |
| ≥9 | 15 (14.9) | 9 (5.6) | 24 (9.2) | |
| Pathologic T stage, n (%) | ||||
| T2 | 52 (48.1) | 123 (75.5) | 175 (64.6) | <0.001 |
| T3a | 41 (38.0) | 28 (17.2) | 69 (25.5) | |
| T3b | 15 (13.9) | 12 (7.4) | 27 (10.0) | |
| Length of PSM (mm), mean±s.d. | 11.1±15.0 | 11.1±15.0 | ||
| Number of PSMs, n (%) | ||||
| 1 | 63 (58.3) | 63 (23.2) | ||
| ≥2 | 45 (41.7) | 45 (16.6) | ||
| Gleason pattern of PSM, n (%) | ||||
| <4 | 48 (44.4) | 48 (17.7) | ||
| ≥4 | 60 (55.6) | 60 (22.1) | ||
| Location of PSM, n (%) | ||||
| Apex | 62 (57.4) | 0 (0) | 62 (22.9) | |
| Base | 21 (19.4) | 0 (0) | 21 (7.7) | |
| Anterior | 37 (34.3) | 0 (0) | 37 (13.7) | |
| Posterolateral | 41 (38.0) | 0 (0) | 41 (15.1) | |
| Positive frozen section, n (%) | ||||
| Periurethra tissue | 44 (40.7) | 19 (11.7) | 63 (23.2) | <0.001 |
| Bladder neck | 6 (5.6) | 2 (1.2) | 8 (3.0) | 0.090 |
| Dorsal vein site | 15 (13.9) | 2 (1.2) | 17 (6.3) | <0.001 |
PSMs: positive surgical margins; NSM: negative surgical margin; s.d.: standard deviation; PSA: prostate-specific antigen; MRI: magnetic resonance imaging; TRUS: transrectal ultrasonography