Table 4.
Baseline characteristics between ER-PR+HER2- and ER-PR-HER2- patients before and after PSM
| Characteristics | Unmatched Cohort | 1:2 propensity score matched (PSM) Cohort | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
|
|
|
|||||||||
| ER-PR+HER2- | ER-PR-HER2- | Unadjusted | ER-PR+HER2- | ER-PR-HER2- | PSM-adjusted | |||||
|
|
|
|
|
|
|
|||||
| N=2417 | % | N=38262 | % | P value | N=2416 | % | N=4826 | % | P value | |
| Age at diagnosis | 0.005 | 0.951 | ||||||||
| <40 | 275 | 11.38% | 3922 | 10.25% | 275 | 11.38% | 556 | 11.52% | ||
| 40-49 | 515 | 21.31% | 7345 | 19.20% | 514 | 21.27% | 1017 | 21.07% | ||
| 50-59 | 613 | 25.36% | 9882 | 25.83% | 613 | 25.37% | 1264 | 26.19% | ||
| 60-69 | 549 | 22.71% | 8928 | 23.33% | 549 | 22.72% | 1102 | 22.83% | ||
| 70-79 | 282 | 11.67% | 5324 | 13.91% | 282 | 11.67% | 538 | 11.15% | ||
| 80+ | 183 | 7.57% | 2861 | 7.48% | 183 | 7.57% | 349 | 7.23% | ||
| Race | 0.157 | 0.303 | ||||||||
| White | 1783 | 73.77% | 27569 | 72.05% | 1782 | 73.76% | 3585 | 74.29% | ||
| Black | 398 | 16.47% | 6763 | 17.68% | 398 | 16.47% | 803 | 16.64% | ||
| Other | 212 | 8.77% | 3628 | 9.48% | 212 | 8.77% | 409 | 8.47% | ||
| Unknown | 24 | 0.99% | 302 | 0.79% | 24 | 0.99% | 29 | 0.60% | ||
| Histological type | 0.953 | 0.598 | ||||||||
| IDC | 2096 | 86.72% | 33205 | 86.78% | 2096 | 86.75% | 4206 | 87.15% | ||
| Non-IDC | 321 | 13.28% | 5057 | 13.22% | 320 | 13.25% | 620 | 12.85% | ||
| Marital | 0.123 | 0.965 | ||||||||
| Married | 1332 | 55.11% | 20530 | 53.66% | 1331 | 55.09% | 2725 | 56.46% | ||
| Unmarried | 947 | 39.18% | 15744 | 41.15% | 947 | 39.20% | 1866 | 38.67% | ||
| Unknown | 138 | 5.71% | 1988 | 5.20% | 138 | 5.71% | 235 | 4.87% | ||
| T stage | 0.090 | |||||||||
| T1 | 1002 | 41.46% | 15862 | 41.46% | 1002 | 41.47% | 1995 | 41.34% | 0.380 | |
| T2 | 1064 | 44.02% | 16397 | 42.85% | 1063 | 44.00% | 2175 | 45.07% | ||
| T3 | 170 | 7.03% | 3247 | 8.49% | 170 | 7.04% | 345 | 7.15% | ||
| T4 | 115 | 4.76% | 1864 | 4.87% | 115 | 4.76% | 212 | 4.39% | ||
| Tx | 66 | 2.73% | 892 | 2.33% | 66 | 2.73% | 99 | 2.05% | ||
| N stage | 0.023 | 0.758 | ||||||||
| N0 | 1631 | 67.48% | 25118 | 65.65% | 1630 | 67.47% | 3294 | 68.26% | ||
| N1 | 584 | 24.16% | 9156 | 23.93% | 584 | 24.17% | 1157 | 23.97% | ||
| N2 | 99 | 4.10% | 2049 | 5.36% | 99 | 4.10% | 198 | 4.10% | ||
| N3 | 76 | 3.14% | 1487 | 3.89% | 76 | 3.15% | 135 | 2.80% | ||
| Nx | 27 | 1.12% | 452 | 1.18% | 27 | 1.12% | 42 | 0.87% | ||
| Grade | 0.022 | 0.422 | ||||||||
| Well | 65 | 2.69% | 734 | 1.92% | 64 | 2.65% | 100 | 2.07% | ||
| Moderately | 387 | 16.01% | 6273 | 16.39% | 387 | 16.02% | 767 | 15.89% | ||
| Poorly | 1867 | 77.24% | 29425 | 76.90% | 1867 | 77.28% | 3775 | 78.22% | ||
| Unknown | 98 | 4.05% | 1830 | 4.78% | 98 | 4.06% | 184 | 3.81% | ||
| median household income (inflation adjusted) | 0.001 | 0.614 | ||||||||
| <50,000 $ | 349 | 14.44% | 4520 | 11.81% | 348 | 14.40% | 659 | 13.66% | ||
| 50,000-59,999 $ | 398 | 16.47% | 6443 | 16.84% | 398 | 16.47% | 806 | 16.70% | ||
| 60,000-69,999 $ | 830 | 34.34% | 13241 | 34.61% | 830 | 34.35% | 1619 | 33.55% | ||
| 70,000 $+ | 840 | 34.75% | 14058 | 36.74% | 840 | 34.77% | 1742 | 36.10% | ||
| Radiotherapy | 0.271 | 0.895 | ||||||||
| No/unknown | 1150 | 47.58% | 18655 | 48.76% | 1150 | 47.60% | 2251 | 46.64% | ||
| Yes | 1267 | 52.42% | 19607 | 51.24% | 1266 | 52.40% | 2575 | 53.36% | ||
| Chemotherapy | <0.001 | 0.936 | ||||||||
| No/unknown | 691 | 28.59% | 9167 | 23.96% | 690 | 28.56% | 1326 | 27.48% | ||
| Yes | 1726 | 71.41% | 29095 | 76.04% | 1726 | 71.44% | 3500 | 72.52% | ||
| Surgery | 0.159 | 0.687 | ||||||||
| No | 161 | 6.66% | 2572 | 6.72% | 161 | 6.66% | 301 | 6.24% | ||
| Yes | 2244 | 92.84% | 35583 | 93.00% | 2243 | 92.84% | 4505 | 93.35% | ||
| Unknown | 12 | 0.50% | 107 | 0.28% | 12 | 0.50% | 20 | 0.41% | ||
ER+/-: estrogen receptor positive/negative; PR+/-: progesterone receptor positive/negative; HER2+/-: human epidermal growth factor receptor 2 positive/negative; PSM: propensity score matching.