Table 1.
Patient characteristics (n=44 852)
| Variable | Surgery alone (n=5500) (n (%)) | NAT (n=3007) (n (%)) | AT (n=10 458) (n (%)) | No surgery (n=25 887) (n (%)) | P value |
| Sex | <0.001 | ||||
| Male | 2677 (49) | 1528 (51) | 5514 (53) | 12 981 (50) | |
| Female | 2823 (51) | 1479 (49) | 4944 (47) | 12 906 (50) | |
| Age group (years) | <0.001 | ||||
| 18–49 | 241 (4) | 267 (9) | 738 (7) | 1708 (7) | |
| 50–69 | 2206 (40) | 1885 (63) | 5986 (57) | 13 418 (52) | |
| 70–84 | 2765 (50) | 832 (28) | 3614 (35) | 9870 (38) | |
| 85+ | 288 (5) | 23 (1) | 120 (1) | 891 (3) | |
| Charlson | <0.001 | ||||
| 0 | 3466 (63) | 2037 (68) | 7003 (67) | 18 265 (71) | |
| 1 | 1528 (28) | 794 (26) | 2776 (27) | 6049 (23) | |
| 2+ | 506 (9) | 176 (6) | 679 (6) | 1573 (6) | |
| Tumour size | <0.001 | ||||
| 2 cm or less | 761 (14) | 382 (13) | 1585 (15) | 1466 (7) | |
| 2.1–5 cm | 3933 (73) | 2205 (77) | 7510 (73) | 16 844 (76) | |
| >5 cm | 686 (13) | 272 (10) | 1170 (11) | 3900 (18) | |
| Location | <0.001 | ||||
| Head | 3978 (72) | 2328 (77) | 7731 (74) | 16 292 (63) | |
| Body | 333 (6) | 236 (8) | 634 (6) | 3872 (15) | |
| Tail | 578 (11) | 122 (4) | 1102 (11) | 1017 (4) | |
| Duct | 47 (1) | 4 (<1) | 68 (1) | 72 (<1) | |
| Other | 564 (10) | 317 (11) | 923 (9) | 4634 (18) | |
| Clinical nodes | <0.001 | ||||
| Negative | 3543 (64) | 1856 (64) | 6705 (67) | 13 533 (58) | |
| Positive | 1702 (36) | 1052 (36) | 3339 (33) | 9655 (42) | |
| Grade | <0.001 | ||||
| 1 | 465 (9) | 233 (11) | 840 (8) | 1195 (18) | |
| 2 | 2703 (52) | 1102 (54) | 5264 (53) | 2789 (41) | |
| 3 | 1946 (38) | 688 (34) | 3709 (37) | 2733 (40) | |
| 4 | 51 (1) | 26 (1) | 92 (1) | 68 (1) | |
| Clinical stage | <0.001 | ||||
| IIA (T3N0) | 6977 (41) | 1441 (48) | 6462 (62) | 5858 (23) | |
| IIB (T1-3N1) | 3886 (23) | 887 (29) | 3360 (32) | 4865 (19) | |
| III (T4N0-1) | 5960 (35) | 679 (23) | 636 (6) | 15 164 (59) | |
| Chemoradiation | <0.001 | ||||
| Chemo only | N/A | 935 (31) | 5643 (54) | 12 966 (50) | |
| Chemoradiation | N/A | 2072 (69) | 4815 (46) | 12 921 (50) | |
| Chemo number | <0.001 | ||||
| Single agent | N/A | 1183 (42) | 6769 (69) | 13 505 (56) | |
| Multiagent | N/A | 1652 (58) | 2974 (31) | 10 501 (44) | |
| Path stage | <0.001 | ||||
| IA | 2 (<1) | 18 (1) | 7 (<1) | N/A | |
| IB | 9 (<1) | 13 (1) | 10 (<1) | N/A | |
| IIA | 70 (1) | 55 (2) | 125 (1) | N/A | |
| IIB | 4595 (91) | 2353 (91) | 9245 (93) | N/A | |
| III | 251 (5) | 126 (5) | 385 (4) | N/A | |
| IV | 106 (2) | 33 (1) | 166 (2) | N/A | |
| Path nodes | <0.001 | ||||
| Negative | 1843 (34) | 1537 (54) | 2733 (27) | N/A | |
| Positive | 3549 (66) | 1293 (46) | 7553 (73) | N/A | |
| Margins | <0.001 | ||||
| No surgery | N/A | N/A | N/A | N/A | |
| R0 | 4481 (81) | 2638 (88) | 8472 (81) | N/A | |
| R1 | 938 (17) | 352 (12) | 1857 (18) | N/A | |
| R2 | 81 (1) | 17 (<1) | 129 (1) | N/A | |
| 30day mortality | <0.001 | ||||
| By group | 544 (10) | 70 (2) | 1 (<1) | N/A | |
| NAT | 70 (2) | ||||
| Upfront surgery | 546 (3.6) | ||||
| 90-day mortality | <0.001 | ||||
| By group | 1033 (19) | 167 (6) | 67 (1) | N/A | |
| NAT | 167 (6) | ||||
| Upfront surgery | 1100 (7) |
AT, adjuvant therapy; chemo, chemotherapy; NAT, neoadjuvant therapy; path, pathology.