Table 4.
Univariate and multivariate analysis of disease‐specific survival (DSS) in matched groups
| Variables | Univariate analysis | Multivariate analysis | |||
|---|---|---|---|---|---|
| HR (95% CI) | P | HR (95% CI) | P | ||
| Year of diagnosis | 1990–1999 | Reference | – | Reference | – |
| 2000–2009 | 0.796 (0.419–1.512) | 0.485 | 0.963 (0.205–4.516) | 0.962 | |
| Age at diagnosis | 15–49 | Reference | – | Reference | – |
| 50–85+ | 3.756 (1.641–8.596) | <0.01 | 4.455 (1.751–11.338) | <0.01 | |
| Race | White | Reference | – | Reference | – |
| Black | 1.738 (0.994–3.039) | 0.053 | 1.723 (0.832–3.571) | 0.143 | |
| Othera | 1.082 (0.540–2.168) | 0.823 | 1.830 (0.843–3.973) | 0.127 | |
| Marital status | Married | Reference | – | Reference | – |
| Unmarriedb | 2.167 (1.176–3.994) | 0.013 | 1.011 (0.424–2.411) | 0.980 | |
| Laterality | Left | Reference | – | Reference | – |
| Right | 1.056 (0.705–1.583) | 0.790 | 0.685 (0.404–1.161) | 0.160 | |
| Group | PLC | Reference | – | Reference | – |
| IDC | 1.078 (0.720–1.614) | 0.715 | 0.946 (0.617–1.450) | 0.798 | |
| Grade | I | Reference | – | Reference | – |
| II | 2.695 (2.602–2.791) | <0.01 | 1.839 (1.775–1.905) | <0.01 | |
| III | 5.641 (5.453–5.835) | <0.01 | 2.722 (2.628–2.820) | <0.01 | |
| AJCC stage | I | Reference | – | Reference | – |
| II | 1.361 (0.792–2.340) | 0.265 | 2.0701.004–4.268) | 0.049 | |
| III | 2.415 (1.325–4.402) | <0.01 | 4.519 (2.001–10.207) | <0.01 | |
| IV | 11.49 (4.531–29.149) | <0.01 | 9.840 (2.699–35.868) | <0.01 | |
| LN status | Negative | Reference | – | Reference | – |
| Positive | 1.287 (0.828–2.001) | 0.263 | 3.512 (1.443–8.549) | <0.01 | |
| ER status | Positive | Reference | – | Reference | – |
| Negative | 2.127 (1.350–3.351) | <0.01 | 1.665 (0.466–5.952) | 0.433 | |
| PR status | Positive | Reference | – | Reference | – |
| Negative | 2.276 (1.457–3.556) | <0.01 | 0.903 (0.436–1.867) | 0.782 | |
| Surgery type | No surgery | Reference | – | Reference | – |
| Lumpectomy | 0.131 (0.056–031) | <0.01 | 0.468 (0.117–1.883) | 0.285 | |
| Mastectomy | 0.222 (0.100–0.490) | <0.01 | 0.676 (0.182–2.505) | 0.557 | |
| Radiation | Yes | Reference | – | Reference | – |
| No | 1.375 (0.636–2.973) | 0.418 | 2.720 (01.084–6.826) | 0.033 | |
Multivariate analysis included year of diagnosis, age at diagnosis, race, marital status, laterality, grade, histology, LN status, ER/PR status, surgery type, and radiation. HR, hazard ratio; CI, confidence interval; ER, estrogen receptor; PLC, Pleomorphic lobular breast carcinoma; IDC, infiltrating ductal carcinoma; LN, lymph node; PR, progesterone receptor. The value of bold is statistically significant.
a
Including American Indian, Alaska Native, Asian, Pacific Islander and others‐unspecified.
b
Including divorced, separated, single (never married) and widowed.