Table 1 Baseline characteristics of elderly patients with breast cancer before and after PSM
Characteristics | Before PSM | After PSM | |||||
|---|---|---|---|---|---|---|---|
Non-PMRT (N = 22,889) | PMRT (N = 4747) | P value | Non-PMRT (N = 3777) | PMRT (N = 3777) | P value | SMD | |
Age group at diagnosis, y | < 0.001 | 0.586 | 0.032 | ||||
70–74 | 8028 (35.1) | 1970 (41.5) | 1476 (39.1) | 1527 (40.4) | |||
75–79 | 6634 (29.0) | 1406 (29.6) | 1123 (29.7) | 1079 (28.6) | |||
80–84 | 4869 (21.3) | 883 (18.6) | 745 (19.7) | 731 (19.4) | |||
85+ | 3358 (14.7) | 488 (10.3) | 433 (11.5) | 440 (11.6) | |||
Race | 0.156 | 0.637 | 0.022 | ||||
White | 18,868 (82.4) | 3906 (82.3) | 3183 (84.3) | 3154 (83.5) | |||
Black | 2054 (9.0) | 460 (9.7) | 346 ( 9.2) | 358 (9.5) | |||
Others | 1967 (8.6) | 381 (8.0) | 248 ( 6.6) | 265 (7.0) | |||
Marital Status | < 0.001 | 0.981 | 0.001 | ||||
Married | 9252 (40.4) | 2057 (43.3) | 1547 (41.0) | 1549 (41.0) | |||
Unmarried | 13,637 (59.6) | 2690 (56.7) | 2230 (59.0) | 2228 (59.0) | |||
Laterality | 0.874 | 0.982 | 0.001 | ||||
Left | 11,821 (51.6) | 2445 (51.5) | 1959 (51.9) | 1957 (51.8) | |||
Right | 11,068 (48.4) | 2302 (48.5) | 1818 (48.1) | 1820 (48.2) | |||
Grade | < 0.001 | 0.988 | 0.004 | ||||
Grade I | 4340 (19.0) | 543 (11.4) | 399 (10.6) | 402 (10.6) | |||
Grade II | 10,491 (45.8) | 2108 (44.4) | 1694 (44.9) | 1697 (44.9) | |||
Grade III + IV | 8058 (35.2) | 2096 (44.2) | 1684 (44.6) | 1678 (44.4) | |||
T | < 0.001 | 0.591 | 0.032 | ||||
T0/T1 | 11,500 (50.2) | 866 (18.2) | 735 (19.5) | 746 (19.8) | |||
T2 | 9134 (39.9) | 2197 (46.3) | 1902 (50.4) | 1859 (49.2) | |||
T3 | 1395 (6.1) | 1036 (21.8) | 749 (19.8) | 748 (19.8) | |||
T4 | 860 (3.8) | 648 (13.7) | 391 (10.4) | 424 (11.2) | |||
N | < 0.001 | 0.506 | 0.035 | ||||
N0 | 14,966 (65.4) | 975 (20.5) | 899 (23.8) | 943 (25.0) | |||
N1 | 5659 (24.7) | 1685 (35.5) | 1514 (40.1) | 1465 (38.8) | |||
N2 | 1460 (6.4) | 1347 (28.4) | 882 (23.4) | 868 (23.0) | |||
N3 | 804 (3.5) | 740 (15.6) | 482 (12.8) | 501 (13.3) | |||
ER | 0.017 | 0.909 | 0.003 | ||||
Negative | 4462 (19.5) | 998 (21.0) | 776 (20.5) | 771 (20.4) | |||
Positive/Borderline | 18,427 (80.5) | 3749 (79.0) | 3001 (79.5) | 3006 (79.6) | |||
PR | < 0.001 | 0.262 | 0.026 | ||||
Negative | 7549 (33.0) | 1719 (36.2) | 1365 (36.1) | 1413 (37.4) | |||
Positive/Borderline | 15,340 (67.0) | 3028 (63.8) | 2412 (63.9) | 2364 (62.6) | |||
Chemotherapy | < 0.001 | 0.531 | 0.015 | ||||
No/Unknown | 18,902 (82.6) | 2311 (48.7) | 2157 (57.1) | 2129 (56.4) | |||
Yes | 3987 (17.4) | 2436 (51.3) | 1620 (42.9) | 1648 (43.6) | |||
LN Surgery | 0.145 | 0.034 | |||||
SLNB | 11,571 (50.6) | 1198 (25.2) | < 0.001 | 1036 (27.4) | 1094 (29.0) | ||
ALND | 11,318 (49.4) | 3549 (74.8) | 2741 (72.6) | 2683 (71.0) | |||