Table 1.
Patient and tumor characteristics for the entire cohort and the case control cohort.
| Variable | Entire Cohort (n = 7565) | Case Control Cohort (n = 1802) | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| BCS + RT | Mastectomy | p-Value | BCS + RT | Mastectomy | p-Value | |||||
| n | (%) * | n | (%) * | n | (%) * | n | (%) * | |||
| All | 6412 | (84.8) | 1153 | (15.2) | 929 | (50.0) | 929 | (50.0) | ||
| Age at diagnosis | <0.001 | n.s. | ||||||||
| <40 years | 353 | (5.5) | 102 | (8.8) | 68 | (7.5) | 62 | (6.9) | ||
| 40–49 years | 1193 | (18.6) | 221 | (19.2) | 201 | (22.3) | 184 | (20.4) | ||
| 50–59 years | 1880 | (29.3) | 282 | (24.5) | 241 | (26.7) | 234 | (26.0) | ||
| 60–69 years | 2043 | (31.9) | 258 | (22.4) | 215 | (23.9) | 225 | (25.0) | ||
| >70 years | 943 | (14.7) | 290 | (25.2) | 176 | (19.5) | 196 | (21.8) | ||
| median (years) | 58.2 | 59.3 | 58.6 | 58.8 | ||||||
| Lateralisation | 0.007 | n.s. | ||||||||
| right | 3181 | (49.6) | 522 | (45.3) | 414 | (45.9) | 414 | (45.9) | ||
| left | 3231 | (50.4) | 631 | (54.7) | 487 | (54.1) | 487 | (54.1) | ||
| Tumour size | <0.001 | n.s. | ||||||||
| pT1 | 4790 | (74.7) | 656 | (56.9) | 514 | (57.0) | 514 | (57.0) | ||
| pT2 | 1622 | (25.3) | 497 | (43.1) | 387 | (43.0) | 387 | (43.0) | ||
| Nodal status | <0.001 | n.s. | ||||||||
| pN0 | 4904 | (76.5) | 791 | (68.6) | 646 | (71.7) | 646 | (71.7) | ||
| pN+ (1–3 LN) | 1508 | (23.5) | 362 | (31.4) | 255 | (28.3) | 255 | (28.3) | ||
| Tumor stage | <0.001 | n.s. | ||||||||
| T1N0 | 3860 | (60.2) | 492 | (42.7) | 395 | (43.8) | 395 | (43.8) | ||
| T2N0 | 1044 | (16.3) | 299 | (25.9) | 251 | (27.9) | 251 | (27.9) | ||
| T1N1 | 930 | (14.5) | 164 | (14.2) | 119 | (13.2) | 119 | (13.2) | ||
| T2N1 | 578 | (9.0) | 198 | (17.2) | 136 | (15.1) | 136 | (15.1) | ||
| Resection status | n.s. | n.s. | ||||||||
| R0 | 5769 | (98.1) | 922 | (98.2) | 812 | (98.5) | 740 | (98.5) | ||
| R1/R2 | 112 | (1.9) | 17 | (1.8) | 12 | (1.5) | 11 | (1.5) | ||
| [unknown] | 531 | (8.2) | 214 | (18.5) | 77 | (8.5) | 150 | (16.6) | ||
| Grade | <0.001 | n.s. | ||||||||
| G1 | 1248 | (19.9) | 98 | (9.1) | 77 | (8.5) | 77 | (8.5) | ||
| G2 | 3610 | (57.6) | 684 | (63.6) | 599 | (66.5) | 599 | (66.5) | ||
| G3/4 | 1411 | (22.5) | 294 | (27.3) | 225 | (25.0) | 225 | (25.0) | ||
| [unknown] | 143 | [2.3] | 77 | [6.6] | ||||||
| Hormone receptor | ||||||||||
| positive | 5674 | (90.2) | 986 | (88.0) | 0.038 | 83 | (9.2) | 83 | (9.2) | n.s. |
| negative | 613 | (9.8) | 135 | (12.0) | 818 | (90.8) | 818 | (90.8) | ||
| [unknown] | 125 | [1.9] | 32 | [2.7] | ||||||
| Chemotherapy | n.s. | n.s. | ||||||||
| no | 4581 | (71.4) | 855 | (74.2) | 660 | (73.3) | 660 | (73.3) | ||
| yes | 1831 | (28.6) | 298 | (25.8) | 241 | (26.7) | 241 | (26.7) | ||
| Endocrine therapy | <0.001 | n.s. | ||||||||
| no | 3076 | (48.0) | 651 | (56.5) | 485 | (53.8) | 485 | (53.8) | ||
| yes | 3336 | (52.0) | 502 | (43.5) | 416 | (46.2) | 416 | (46.2) | ||
* Percentages of the presented subcategories are related to the sum of each item with available data; missing values are not taken into account. Hormone receptor positive: estrogen and/or progesterone positive (>1%). BCS: breast conserving surgery, RT: radiotherapy, n.s.: not significant.