Table 2.
Univariate Cox regression analysis of the whole cohort, the Right-sided cohort, and the Left-sided cohort
| Patients Characteristics | Full cohort | Right-sided | Left-sided | |||
|---|---|---|---|---|---|---|
| HR (95% CI) | P | HR (95% CI) | P | HR (95% CI) | P | |
| Age at diagnosis | < 0.001 | < 0.001 | < 0.001 | |||
| < 40 | 1.000 | 1.000 | 1.000 | |||
| 40–49 | 1.101 (0.987–1.229) | 0.319 | 1.080 (0.928–1.258) | 0.319 | 1.126 (0.961–1.320) | 0.143 |
| 50–59 | 1.158 (1.048–1.279) | 0.007 | 1.205 (1.051–1.381) | 0.007 | 1.086 (0.938–1.256) | 0.270 |
| 60–69 | 1.557 (1.414–1.716) | < 0.001 | 1.499 (1.313–1.711) | < 0.001 | 1.523 (1.321–1.757) | < 0.001 |
| > 70 | 3.364 (3.063–3.695) | < 0.001 | 2.999 (2.636–3.411) | < 0.001 | 3.646 (3.178–4.183) | < 0.001 |
| Gender | ||||||
| Female vs. Male | 0.989 (0.960–1.019) | 0.018 | 0.475 | 0.875 | 0.839–0.913 | < 0.001 |
| Race | < 0.001 | < 0.001 | < 0.001 | |||
| Black | 1.000 | 1.000 | 1.000 | |||
| White | 0.994 (0.959–1.031) | 0.756 | 1.056 (1.010–1.105) | 0.017 | 0.879 (0.827–0.935) | < 0.001 |
| Hispanic/Latino | 0.861 (0.730–1.016) | 0.077 | 0.913 (0.743–1.122) | 0/388 | 0.793 (0.601–1.046) | 0.101 |
| Asian or Pacific Islander and others | 0.699 (0.659–0.742) | < 0.001 | 0.766 (0.708–0.828) | < 0.001 | 0.671 (0.614–0.734) | < 0.001 |
| Unknown | 0.445 (0.320–0.618) | < 0.001 | 0.449 (0.295–0.684) | < 0.001 | 0.449 (0.265–0.761) | 0.003 |
| Hispanic | ||||||
| Yes vs. No | 0.834 (0.799–0.871) | < 0.001 | 0.838 (0.793–0.885) | < 0.001 | 0.857 (0.798–0.921) | < 0.001 |
| T stage | < 0.001 | < 0.001 | < 0.001 | |||
| T0–T2 (0, 2, 3) | 1.000 | 1.000 | 1.000 | |||
| T3–T4 (4, 5) | 1.973 (1.889–2.061) | < 0.001 | 1.784 (1.690–1.883) | < 0.001 | 2.212 | 2.055–2.381 |
| TX (6) | 1.315 (0.900–1.922) | 0.157 | 1.188 (0.714–1.976) | 0.507 | 1.575 (0.891–2.786) | 0.118 |
| N stage | ||||||
| N2 vs. N1 | 1.581 (1.543–1.620) | < 0.001 | 1.657 (1.608–1.707) | < 0.001 | 1.415 (1.355–1.477) | < 0.001 |
| Chemotherapy | ||||||
| Yes vs. No | 0.408 (0.398–0.418) | < 0.001 | 0.430 (0.417–0.443) | < 0.001 | 0.386 (0.370–0.403) | < 0.001 |
| Radiotherapy | < 0.001 | < 0.001 | 0.001 | |||
| No | 1.000 | 1.000 | 1.000 | |||
| Yes | 0.517 (0.410–0.654) | < 0.001 | 0.637 (0.469–0.865) | 0.004 | 0.508 (0.351–0.735) | < 0.001 |
| Unknown | 0.524 (0.421–0.651) | < 0.001 | 0.515 (0.390–0.680) | < 0.001 | 0.506 (0.356–0.721) | < 0.001 |
| Marital status | < 0.001 | < 0.001 | < 0.001 | |||
| Single, separated, divorced, | 1.000 | 1.000 | 1.000 | |||
| Married (including common law) | 0.843 (0.818–0.870) | < 0.001 | 0.872 (0.839–0.907) | < 0.001 | 0.788 (0.748–0.829) | < 0.001 |
| Widowed | 1.681 (1.623–1.740) | < 0.001 | 1.592 (1.524–1.659) | < 0.001 | 1.746 (1.643–1.856) | < 0.001 |
| Unknown | 1.065 (0.996–1.139) | 0.065 | 1.082 (0.998–1.173) | 0.056 | 0.984 (0.873–1.110) | 0.792 |
| Pathology grade | < 0.001 | < 0.001 | < 0.001 | |||
| Well-differentiated | 1.000 | 1.000 | 1.000 | |||
| Moderately differentiated | 1.119 (1.056–1.186) | < 0.001 | 1.197 (1.112–1.289) | < 0.001 | 1.020 (0.930–1.119) | 0.669 |
| Poorly differentiated | 1.635 (1.540–1.736) | < 0.001 | 1.673 (1.551–1.804) | < 0.001 | 1.436 (1.300–1.586) | < 0.001 |
| Undifferentiated | 1.981 (1.825–2.150) | < 0.001 | 1.988 (1.802–2.192) | < 0.001 | 1.735 (1.476–2.040) | < 0.001 |
| Unknown | 1.308 (1.188–1.439) | < 0.001 | 1.403 (1.247–1.578) | < 0.001 | 1.113 (0.942–1.315) | 0.208 |
| Positive lymph node | < 0.001 | < 0.001 | < 0.001 | |||
| 0 | 1.000 | 1.000 | 1.000 | |||
| 1 | 0.943 (0.851–1.045) | 0.265 | 0.933 (0.819–1.062) | 0.293 | 0.932 (0.787–1.105) | 0.418 |
| 2–3 | 1.085 (0.979–1.202) | 0.121 | 1.082 (0.951–1.232) | 0.232 | 1.058 (0.893–1.253) | 0.514 |
| 4–6 | 1.347 (1.215–1.495) | < 0.001 | 1.385 (1.216–1.578) | < 0.001 | 1.236 (1.041–1.467) | 0.015 |
| ≥ 7 | 2.012 (1.814–2.232) | < 0.001 | 2.101 (1.844–2.393) | < 0.001 | 1.713 (1.441–2.035) | < 0.001 |
| Lymph nodes ratio | < 0.001 | < 0.001 | < 0.001 | |||
| < 0.07 | 1.000 | 1.000 | 1.000 | |||
| 0.07–0.25 | 1.312 (1.267–1.360) | < 0.001 | 1.375 (1.318–1.435) | < 0.001 | 1.245 (1.168–1.327) | < 0.001 |
| 0.25–0.50 | 1.771 (1.704–1.842) | < 0.001 | 1.942 (1.853–2.036) | < 0.001 | 1.597 (1.490–1.711) | < 0.001 |
| 0.50–1.0 | 2.873 (2.761–2.990) | < 0.001 | 3.302 (3.147–3.466) | < 0.001 | 2.446 (2.279–2.625) | < 0.001 |
| Tumor site | ||||||
| Left-sided vs. Right-sided | 0.716 (0.698–0.734) | < 0.001 | ||||
| aTotal number of lymph node | ||||||
| ≥ 12 vs. < 12 | 0.758 (0.739–0.778) | < 0.001 | 0.692 (0.670–0.715) | < 0.001 | 0.765 (0.733–0.798) | < 0.001 |
| bTotal number of lymph node | 0.985 (0.983–0.986) | < 0.001 | 0.980 (0.978–0.982) | < 0.001 | 0.986 (0.983–0.988) | < 0.001 |
| cTotal number of lymph nodes | ||||||
| ≥ 11 vs. < 11 | 0.742 (0.706–0.779) | < 0.001 | ||||
Abbreviations: aTotal number of lymph nodes as the Categorical variable
bTotal number of lymph nodes as a continuous variable
cThe threshold of total number of lymph nodes as 11 in the Left-sided cohort