Table 1.
Patient and tumor characteristics by surgeon experience*. Note that this is the same table as that presented in our previous manuscript examining the learning curve for biochemical recurrence, as the same data set was used for both analyses.
| Surgeon experience (no. of cases before the incident case) | P† | |||||
|---|---|---|---|---|---|---|
| < 50 | 50–99 | 100–249 | 250–999 | ≥1000 | ||
| Number of patients | 1402 | 696 | 1575 | 2940 | 1152 | |
| Patient or tumor characteristic | ||||||
| Median preoperative PSA level, ng/mL (IQR) | 7.3 (5.1–12.1) | 6.8 (4.9–9.9) | 7.3 (5.2–12.0) | 6.6 (4.8–9.4) | 6.0 (4.7–8.0) | .002 |
| Median age at surgery, yr (IQR) | 63 (58–67) | 62 (57– 66) | 61 (56–66) | 61 (56–66) | 59 (54–64) | <.001 |
| Gleason grade, no. (%) | .6 | |||||
| ≤5 | 95 (7) | 31 (4) | 146 (9) | 133 (5) | 25 (2) | |
| 6 | 547 (39) | 286 (41) | 556 (35) | 1117 (38) | 529 (46) | |
| 7 | 669 (48) | 341 (49) | 748 (47) | 1489 (51) | 553 (48) | |
| 8 | 75 (5) | 27 (4) | 86 (5) | 133 (5) | 26 (2) | |
| ≥9 | 16 (1) | 11 (2) | 39 (2) | 68 (2) | 19 (2) | |
| Extraprostatic extension | 419 (30) | 196 (28) | 491 (31) | 893 (30) | 262 (23) | .004 |
| Seminal vesicle invasion | 164 (12) | 64 (9) | 166 (11) | 249 (8) | 52 (5) | <.001 |
| Lymph node involvement | 56 (4) | 28 (4) | 53 (3) | 118 (4) | 36 (3) | .5 |
| Non-organ confined cancer‡ | 458 (33) | 216 (31) | 536 (34) | 940 (32) | 273 (24) | <.001 |
| Number of operations performed by time period (%) | <.001 | |||||
| 1987–1990 | 202 (14) | 32 (5) | 152 (10) | 51 (2) | 0 (0)§ | |
| 1991–1995 | 532 (38) | 179 (26) | 646 (41) | 864 (29) | 0 (0)§ | |
| 1996–2000 | 504 (36) | 293 (42) | 441 (28) | 1294 (44) | 485 (42) | |
| 2001–2003 | 164 (12) | 192 (28) | 336 (21) | 731 (25) | 667 (58) | |
| Unadjusted outcomes | ||||||
| Positive surgical margin, no. (%) | 582 (42) | 235 (34) | 493 (31) | 624 (21) | 125 (11) | |
| Five-year probability of recurrence, % (95% CI) | 27 (24 to 30) | 23 (19 to 27) | 19 (17 to 22) | 16 (14 to 17) | 8 (6 to 10) | |
PSA = prostate-specific antigen; IQR = interquartile range; CI = confidence interval.
P values (two-sided) were determined by regression models in which the number of prior cases was entered as a continuous variable, with adjustment for clustering by surgeon.
Non-organ confined cancer = extraprostatic extension, seminal vesicle invasion, or lymph node involvement.
The two surgeons who treated 1000 or more patients treated their 1000th cases in 1996 and 2001, respectively. Hence, no patient who received surgery before 1996 was operated on by a surgeon who, at the time, had 1000 or more prior cases.