Table 4.
Cox regression analysis of prognostic factors for overall survival in T1 colon cancer
| Unadjusted | Adjusted | Variable selection | ||||
|---|---|---|---|---|---|---|
| HR* (95% CI*) | P | HR (95% CI) | P | HR (95% CI) | P | |
| N stage | ||||||
| N0 | Reference | |||||
| N1/N2 | 1.11 (0.95–1.29) | 0.21 | ||||
| Tumor size (cm) | ||||||
| < 1 | Reference | Reference | Reference | |||
| 1–1.9 | 1.16 (0.98–1.39) | 0.091 | 1.08 (0.91–1.29) | 0.405 | 1.09 (0.91–1.30) | 0.348 |
| 2–2.9 | 1.41 (1.17–1.69) | < 0.001 | 1.21 (1.01–1.46) | 0.043 | 1.23 (1.02–1.48) | 0.029 |
| 3+ | 1.45 (1.22–1.73) | < 0.001 | 1.29 (1.08–1.53) | 0.005 | 1.30 (1.09–1.54) | 0.004 |
| Not stated | 0.86 (0.72–1.02) | 0.086 | 0.93 (0.78–1.11) | 0.433 | 0.93 (0.78–1.11) | 0.448 |
| Histology | ||||||
| Adenocarcinoma | Reference | Reference | ||||
| Mucinous carcinoma | 1.47 (1.14–1.91) | 0.003 | 1.12 (0.86–1.46) | 0.391 | ||
| CEA* | ||||||
| Positive | Reference | Reference | Reference | |||
| Negative | 0.40 (0.33–0.48) | < 0.001 | 0.50 (0.41–0.60) | < 0.001 | 0.49 (0.41–0.60) | < 0.001 |
| Borderline/unknown | 0.51 (0.43–0.61) | < 0.001 | 0.61 (0.51–0.73) | < 0.001 | 0.61 (0.51–0.72) | < 0.001 |
| Grade | ||||||
| Well-differentiated | Reference | Reference | ||||
| Moderately differentiated | 1.04 (0.91–1.19) | 0.600 | 1.05 (0.91–1.20) | 0.502 | ||
| Poorly differentiated | 1.10 (0.88–1.37) | 0.422 | 1.12 (0.89–1.40) | 0.340 | ||
| Undifferentiated | 2.31 (1.43–3.72) | < 0.001 | 2.02 (1.25–3.26) | 0.004 | ||
| Unknown | 0.90 (0.73–1.11) | 0.320 | 1.05 (0.85–1.30) | 0.666 | ||
| Year | ||||||
| 2004–2006 | Reference | |||||
| 2007–2009 | 1.02 (0.90–1.16) | 0.745 | ||||
| 2010–2012 | 0.86 (0.74–1.01) | 0.063 | ||||
| Age (years) | ||||||
| Up to 49 | Reference | Reference | Reference | |||
| 50–64 | 1.84 (1.25–2.71) | 0.002 | 1.92 (1.30–2.82) | 0.001 | 1.91 (1.30–2.82) | 0.001 |
| 65–79 | 5.39 (3.72–7.82) | < 0.001 | 5.33 (3.67–7.76) | < 0.001 | 5.37 (3.70–7.80) | < 0.001 |
| 80+ | 17.44 (12.00–25.36) | < 0.001 | 15.68 (10.72–22.91) | < 0.001 | 15.82 (10.86–23.04) | < 0.001 |
| Gender | ||||||
| Male | Reference | |||||
| Female | 0.99 (0.89–1.10) | 0.827 | ||||
| Race | ||||||
| Black | Reference | Reference | Reference | |||
| White | 1.00 (0.85–1.17) | 0.954 | 0.78 (0.67–0.92) | 0.004 | 0.78 (0.66–0.92) | 0.003 |
| Others | 0.56 (0.42–0.74) | < 0.001 | 0.50 (0.38–0.66) | < 0.001 | 0.50 (0.38–0.66) | < 0.001 |
| Marital status | ||||||
| Married | Reference | Reference | Reference | |||
| Single/widowed | 2.10 (1.88–2.35) | < 0.001 | 1.38 (1.23–1.55) | < 0.001 | 1.38 (1.23–1.55) | < 0.001 |
| Other/unknown | 1.05 (0.89–1.25) | 0.562 | 1.02 (0.86–1.21) | 0.823 | 1.02 (0.86–1.21) | 0.839 |
| Primary site | ||||||
| Cecum | Reference | Reference | ||||
| Ascending colon | 0.99 (0.86–1.13) | 0.866 | 1.07 (0.93–1.23) | 0.369 | ||
| Hepatic flexure | 0.87 (0.68–1.11) | 0.264 | 0.95 (0.73–1.21) | 0.658 | ||
| Transverse colon | 0.73 (0.58–0.91) | 0.006 | 0.91 (0.73–1.14) | 0.405 | ||
| Splenic flexure | 0.72 (0.48–1.07) | 0.106 | 1.05 (0.70–1.58) | 0.803 | ||
| Descending colon | 0.64 (0.49–0.85) | 0.002 | 0.96 (0.73–1.28) | 0.802 | ||
| Sigmoid colon | 0.58 (0.50–0.67) | < 0.001 | 1.01 (0.87–1.17) | 0.883 | ||
*HR hazard ratio, 95% CI 95% confidence intervals, CEA carcinoembryonic antigen