Table 1.
Baseline characteristics by local treatment strategy for each cohort*
| MarketScan cohort* |
SEER-Medicare cohort* |
|||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Lump+WBI | Lump+ Brachy | Lump alone | Mast alone | Mast+Recon | Lump+WBI | Lump+ Brachy | Lump alone | Mast alone | Mast+Recon | |
| (n = 16 700) | (n = 2313) | (n = 2513) | (n = 11 432) | (n = 11 386) | (n = 29 764) | (n = 2733) | (n = 7502) | (n = 19 096) | (n = 1772) | |
| Variable | No. (%) | No. (%) | No. (%) | No. (%) | No. (%) | No. (%) | No. (%) | No. (%) | No. (%) | No. (%) |
| Age, y | ||||||||||
| <40 | 592 (3.5) | 5 (0.2) | 259 (10.3) | 697 (6.1) | 1221 (10.7) | |||||
| 40–49 | 4480 (26.8) | 381 (16.5) | 911 (36.3) | 2519 (22.0) | 4320 (37.9) | |||||
| 50–59 | 8657 (51.8) | 1354 (58.5) | 1135 (45.2) | 5861 (51.3) | 4753 (41.7) | |||||
| 60–64 | 2971 (17.8) | 573 (24.8) | 208 (8.3) | 2355 (20.6) | 1092 (9.6) | |||||
| 66–69 | 7368 (24.8) | 661 (24.2) | 644 (8.6) | 3051 (16.0) | 758 (42.8) | |||||
| 70–74 | 8981 (30.2) | 823 (30.1) | 963 (12.8) | 4692 (24.6) | 614 (34.7) | |||||
| 75–79 | 7376 (24.8) | 661 (24.2) | 1379 (18.4) | 4746 (24.9) | 293 (16.5) | |||||
| 80–84 | 4431 (14.9) | 429 (15.7) | 1892 (25.2) | 3968 (20.8) | 81 (4.6) | |||||
| 85+ | 1608 (5.4) | 159 (5.8) | 2624 (35.0) | 2639 (13.8) | 26 (1.5) | |||||
| Race | ||||||||||
| White | 26 508 (89.1) | 2467 (90.3) | 6643 (88.6) | 16 363 (85.7) | 1642 (92.7) | |||||
| Black | 1678 (5.6) | 151 (5.5) | 498 (6.6) | 1475 (7.7) | 82 (4.6) | |||||
| Other | 1578 (5.3) | 115 (4.2) | 361 (4.8) | 1258 (6.6) | 48 (2.7) | |||||
| Type of coverage | ||||||||||
| non-HMO | 13 713 (82.1) | 1989 (86.0) | 2035 (81.0) | 9304 (81.4) | 9200 (80.8) | |||||
| HMO | 2987 (17.9) | 324 (14.0) | 478 (19.0) | 2128 (18.6) | 2186 (19.2) | |||||
| Covered individual | ||||||||||
| Employ | 10 304 (61.7) | 1461 (63.2) | 1439 (57.3) | 6651 (58.2) | 6641 (58.3) | |||||
| Depen | 6396 (38.3) | 852 (36.8) | 1074 (42.7) | 4781 (41.8) | 4745 (41.7) | |||||
| Comorbidity | ||||||||||
| 0 | 15 145 (90.7) | 2065 (89.3) | 2289 (91.1) | 9676 (84.6) | 10 564 (92.8) | 19 971 (67.1) | 1810 (66.2) | 4216 (56.2) | 11 098 (58.1) | 1270 (71.7) |
| 1 | 1355 (8.1) | 212 (9.2) | 183 (7.3) | 1396 (12.2) | 721 (6.3) | 6723 (22.6) | 627 (22.9) | 1948 (26.0) | 5038 (26.4) | 378 (21.3) |
| ≥2 | 200 (1.2) | 36 (1.6) | 41 (1.6) | 360 (3.2) | 101 (0.9) | 3070 (10.3) | 296 (10.8) | 1338 (17.8) | 2960 (15.5) | 124 (7.0) |
| Year | ||||||||||
| 2000 | 270 (1.6) | 4 (0.2) | 126 (5.0) | 275 (2.4) | 221 (1.9) | 2015 (6.77) | 30 (1.1) | 481 (6.4) | 1755 (9.2) | 96 (5.4) |
| 2001 | 300 (1.8) | 1 (0.0) | 116 (4.6) | 282 (2.5) | 238 (2.1) | 2288 (7.69) | 14 (0.5) | 524 (7.0) | 1938 (10.2) | 114 (6.4) |
| 2002 | 336 (2.0) | 9 (0.4) | 182 (7.2) | 462 (4.0) | 326 (2.9) | 2528 (8.49) | 63 (2.3) | 597 (8.0) | 1977 (10.4) | 117 (6.6) |
| 2003 | 635 (3.8) | 51 (2.2) | 240 (9.6) | 658 (5.8) | 529 (4.7) | 2581 (8.67) | 110 (4.0) | 519 (6.9) | 1781 (9.3) | 122 (6.9) |
| 2004 | 824 (4.9) | 65 (2.8) | 230 (9.2) | 649 (5.7) | 594 (5.2) | 2550 (8.57) | 142 (5.2) | 616 (8.2) | 1708 (8.9) | 122 (6.9) |
| 2005 | 1125 (6.7) | 92 (4.0) | 272 (10.8) | 903 (7.9) | 750 (6.6) | 2406 (8.08) | 191 (7.0) | 649 (8.7) | 1574 (8.2) | 119 (6.7) |
| 2006 | 1212 (7.3) | 176 (7.6) | 239 (9.5) | 885 (7.7) | 804 (7.1) | 2479 (8.33) | 256 (9.4) | 680 (9.1) | 1483 (7.8) | 113 (6.4) |
| 2007 | 1921 (11.5) | 321 (13.9) | 267 (10.6) | 1172 (10.3) | 1252 (11.0) | 2502 (8.41) | 333 (12.2) | 616 (8.2) | 1505 (7.9) | 162 (9.1) |
| 2008 | 1870 (11.2) | 382 (16.5) | 214 (8.5) | 1288 (11.3) | 1307 (11.5) | 2476 (8.32) | 371 (13.6) | 626 (8.3) | 1469 (7.7) | 170 (9.6) |
| 2009 | 2748 (16.5) | 419 (18.1) | 288 (11.5) | 1721 (15.1) | 1795 (15.8) | 2618 (8.8) | 390 (14.3) | 641 (8.5) | 1389 (7.3) | 219 (12.4) |
| 2010 | 2915 (17.5) | 424 (18.3) | 209 (8.3) | 1727 (15.1) | 1848 (16.2) | 2619 (8.8) | 418 (15.3) | 745 (9.9) | 1294 (6.8) | 213 (12.0) |
| 2011 | 2544 (15.2) | 369 (16.0) | 130 (5.2) | 1410 (12.3) | 1722 (15.1) | 2702 (9.08) | 415 (15.2) | 808 (10.8) | 1223 (6.4) | 205 (11.6) |
| Chemotherapy | ||||||||||
| No | 10 263 (61.5) | 1876 (81.1) | 2200 (87.5) | 8554 (74.8) | 7248 (63.7 | 24 658 (82.9) | 2484 (90.9) | 7124 (95.0) | 15 710 (82.3) | 1263 (71.28) |
| Yes | 6437 (38.5) | 437 (18.9) | 313 (12.5) | 2878 (25.2) | 4138 (36.3) | 5106 (17.2) | 249 (9.1) | 378 (5.0) | 3386 (17.7) | 509 (28.72) |
| Trastuzumab | ||||||||||
| No | 15 672 (93.8) | 2233 (96.5) | 2482 (98.77) | 11 005 (96.26) | 10 643 (93.5) | 28 998 (97.4) | 2688 (98.4) | 7439 (99.2) | 18 591 (97.4) | 1665 (94.0) |
| Yes | 1028 (6.2) | 80 (3.5) | 31 (1.23) | 427 (3.74) | 743 (6.5) | 766 (2.57) | 45 (1.7) | 63 (0.8) | 505 (2.6) | 107 (6.0) |
| Axillary surgery | ||||||||||
| No | 3456 (20.7) | 514 (22.2) | 1788 (71.2) | 5830 (51.0) | 2009 (17.6) | 2042 (6.86) | 106 (3.9) | 3347 (44.6) | 943 (4.9) | 32 (1.8) |
| Yes | 13 244 (79.3) | 1799 (77.8) | 725 (28.9) | 5602 (49.0) | 9377 (82.4) | 27 722 (93.1) | 2627 (96.1) | 4155 (55.4) | 18 153 (95.1) | 1740 (98.19) |
| Bilateral mastectomy | ||||||||||
| No | 16 700 (100) | 2313 (100) | 2513 (100) | 10 801 (94.5) | 8015 (70.4) | 29 764 (100) | 2733 (100) | 7502 (100) | 18 542 (97.1) | 1485 (83.8) |
| Yes | 0 (0) | 0 (0) | 0 (0) | 631 (5.5) | 3371 (29.6) | 0 (0) | 0 (0) | 0 (0) | 554 (2.9) | 287 (16.2) |
| Node positive | ||||||||||
| No | 14 520 (87.0) | 2259 (97.7) | 2381 (94.8) | 10 239 (89.6) | 9986 (87.7) | 25 307 (85.0) | 2604 (95.3) | 7038 (93.8) | 15 462 (81.0) | 1464 (82.62) |
| Yes | 2180 (13.1) | 54 (2.3) | 132 (5.3) | 1193 (10.4) | 1400 (12.3) | 4457 (15.0) | 129 (4.7) | 464 (6.2) | 3634 (19.0) | 308 (17.38) |
| Endocrine therapy | ||||||||||
| Yes | 9930 (59.5) | 1436 (62.1) | 585 (23.3) | 3574 (31.3) | 5107 (44.9) | |||||
| No | 6770 (40.5) | 877 (37.9) | 1928 (76.7) | 7858 (68.7) | 6279 (55.2) | |||||
| ER positive | ||||||||||
| Yes | 24 414 (82.0) | 2387 (87.3) | 6102 (81.3) | 14060 (73.6) | 1389 (78.39) | |||||
| No | 3441 (11.6) | 208 (7.6) | 553 (7.4) | 2684 (14.1) | 247 (13.94) | |||||
| Unknown | 1909 (6.41) | 138 (5.1) | 847 (11.3) | 2352 (12.3) | 136 (7.67) | |||||
*
P value < .001 (chi-square) for all comparisons of treatment strategy by patient and treatment characteristics for each cohort. Brachy = brachytherapy; Depen = dependent; Employ = employee; HMO = Health Maintenance Organization; Lump = lumpectomy; Mast = mastectomy; SEER = Surveillance, Epidemiology, and End Results; WBI = whole breast irradiation.