Table 2. Surgeon volume and treatment and histological prognostic factors.
| High (6) (⩾50) | Medium (4) (11–49) | Low (15) (⩽10) | Total (25) | Test, P-value | |
|---|---|---|---|---|---|
| Surgeon volumea, N | |||||
| Therapeutic procedures, N (%) | Cusick's test for trend | ||||
| BCT | 1133 (54) | 299 (56) | 29 (38) | 1461 (54) | z=1.15, P=0.25 |
| Radiotherapy | 724 (35) | 169 (32) | 615 (20) | 908 (34) | z=−2.6, P=0.014 |
| Tamoxifen | 1129 (54) | 211 (39) | 21 (28) | 1361 (50) | z=−7.23, P<0.01 |
| Chemotherapy | 74 (3.5) | 9 (1.7) | 4 (5.3) | 88 (3.3) | z=−1.13, P=0.26 |
| Invasive status, N (%) | Wilcoxin's rank sum | ||||
| Invasive tumours | 1636 (78) | 422 (79) | 63 (83) | 2121 (78) | P=0.97 |
| In situ tumours | 448 (21) | 112 (21) | 12 (16) | 572 (21) | |
| Missingb | 8 (0.38) | 2 (0.37) | 1 (1.32) | 11 (0.41) | |
| All tumours | 2092 | 536 | 76 | 2704 | |
| Invasive tumours onlyc, N (%): 2121 (100) | |||||
| Malignant nodesa | Spearman's rank | ||||
| None | 1221 (75) | 312 (74) | 37 (59) | 1570 (74) | correlation |
| Few (1–4) | 299 (18) | 79 (19) | 18 (29) | 396 (19) | P=0.59 |
| Medium (5–9) | 60 (3.7) | 14 (3.3) | 3 (4.8) | 77 (3.6) | |
| Lots (⩾10) | 18 (1.1) | 9 (2.1) | 0 | 27 (1.3) | |
| Missingb | 38 (2.3) | 8 (1.9) | 5 (7.9) | 51 (2.4) | |
| Size (mm)a, N | 1620 | 417 | 60 | 2097 | Spearman's rank |
| Median (IQR) | 13 (9–18) | 13 (9–19) | 15 (10.5–22) | 13 (9–18) | correlation |
| Range | 1–99 | 1–99 | 2–60 | 1–99 | P=0.53 |
| Missingb | 16 (0.8) | 5 (0.9) | 3 (3.9) | 24 (0.9) | |
| Grade | |||||
| 1 | 528 (32) | 115 (27) | 10 (16) | 653 (31) | Cusick's test |
| 2 | 711 (43) | 181 (43) | 27 (43) | 919 (43) | for trend |
| 3 | 224 (14) | 55 (13) | 9 (14) | 288 (14) | P=0.85 |
| Missingb | 173 (11) | 71 (17) | 17 (27) | 261 (12) | |
| NPIa | Spearman rank | ||||
| Good | 936 (57) | 220 (52) | 19 (30) | 1175 (55) | Correlation |
| Moderate | 391 (24) | 106 (25) | 19 (30) | 516 (24) | P=0.94 |
| Poor | 87 (5.3) | 17 (4.0) | 4 (6.4) | 108 (5.1) | |
| Missingb | 222 (14) | 79 (19) | 21 (33) | 322 (15) | |
BCT=breast conservation therapy; IQR=interquartile range.
All tumours, N (%): 2704 (100), one patient with missing surgeon ID.
a
Surgeon volume, malignant nodes, size and Nottingham Prognostic Index analysed as continuous variables.
b
Missing values not included in analyses.
c
These data not available for noninvasive tumours.