Table 3. Factors Associated With Overall Survival at 5 Years.
| Factor | Training set | Testing set | ||
|---|---|---|---|---|
| HR (95% CI) | P value | HR (95% CI) | P value | |
| Sex | ||||
| Women | 1 [Reference] | NA | 1 [Reference] | NA |
| Men | 1.23 (1.16-1.30) | <.001 | 1.303 (1.17-1.44) | <.001 |
| Age | 1.02 (1.01-1.02) | <.001 | 1.02 (1.01-1.02) | <.001 |
| Smoking status | ||||
| Nonsmoker | 1 [Reference] | NA | 1 [Reference] | NA |
| Smoker | 1.66 (1.46-1.89) | <.001 | 1.92 (1.51-2.44) | <.001 |
| Stage | ||||
| 1 | 1 [Reference] | NA | 1 [Reference] | NA |
| 2 | 1.73 (1.54-1.94) | <.001 | 1.32 (1.08-1.61) | <.001 |
| 3 | 2.92 (2.66-3.20) | <.001 | 2.44 (2.08-2.86) | <.001 |
| 4 | 5.08 (4.65-5.54) | <.001 | 4.83 (4.16-5.62) | <.001 |
| Histologic type | ||||
| Adenocarcinoma | 1 [Reference] | NA | 1 [Reference] | NA |
| Squamous cell carcinoma | 1.05 (0.98-1.13) | .16 | 1.14 (1.01-1.29) | .03 |
| Other | 1.52 (1.40-1.65) | <.001 | 1.32 (1.16-1.51)) | <.001 |
| BMI | ||||
| Reference range | 1 [Reference] | NA | 1 [Reference] | NA |
| Obesity | 0.88 (0.80-0.97) | .01 | 0.86 (0.73-1.01) | .06 |
| Overweight | 0.90 (0.83-0.98) | .02 | 0.90 (0.78-1.04) | .15 |
| Underweight | 1.28 (1.06-1.55) | .01 | 0.94 (0.65-1.35) | .73 |
| Missing | 1.38 (1.28-1.49) | <.001 | 1.32 (1.16-1.51) | <.001 |
| Albumin, g/dL | ||||
| ≤3.5 | 1 [Reference] | NA | 1 [Reference] | NA |
| >3.5 | 0.66 (0.61-0.71) | <.001 | 0.59 (0.52-0.68) | <.001 |
| Missing | 0.48 (0.41-0.57) | <.001 | 0.45 (0.34-0.61) | <.001 |
| Alkaline phosphatase, U/L | ||||
| ≤140 | 1 [Reference] | NA | 1 [Reference] | NA |
| >140 | 1.40 (1.27-1.54) | <.001 | 1.54 (1.29-1.83) | <.001 |
| Missing | 1.17 (0.99-1.38) | .06 | 1.09 (0.81-1.47) | .57 |
| Creatinine, mg/dL | ||||
| Reference rangea | 1 [Reference] | NA | 1 [Reference] | NA |
| High | 1.02 (0.95-1.10) | .57 | 0.93 (0.81-1.06) | .27 |
| Low | 1.45 (1.26-1.67) | <.001 | 1.45 (1.26-1.67) | <.001 |
| Missing | 1.19 (0.90-1.57) | .22 | 0.93 (0.81-1.06) | .16 |
| Hemoglobin, g/dL | ||||
| Reference rangeb | 1 [Reference] | NA | 1 [Reference] | NA |
| High | 1.35 (1.08-1.70) | .01 | 1.34 (0.89-2.03) | .15 |
| Low | 1.16 (1.09-1.24) | <.001 | 1.06 (0.95-1.19) | .28 |
| Missing | 1.56 (0.96-2.55) | .07 | 0.54 (0.18-1.65) | .32 |
| Red cell distribution width, % | ||||
| ≤14.5 | 1 [Reference] | NA | 1 [Reference] | NA |
| >14.5 | 1.12 (1.05-1.20) | <.001 | 1.36 (1.20-1.53) | <.001 |
| Missing | 0.74 (0.46-1.20) | .23 | 0.84 (0.27-2.61) | .77 |
| WBC count, per μL | ||||
| 4500-11 000 | 1 [Reference] | NA | 1 [Reference] | NA |
| ≥11 000 | 1.17 (1.09-1.25) | <.001 | 1.24 (1.10-1.40) | <.001 |
| Missing | 1.01 (0.64-1.59) | .97 | 2.82 (0.73-10.91) | .13 |
| Neutrophil-lymphocyte ratio | ||||
| ≤4 | 1 [Reference] | NA | 1 [Reference] | NA |
| >4 | 1.34 (1.25-1.43) | <.001 | 1.23 (1.10-1.38) | <.001 |
| Missing | 0.85 (0.76-0.96) | .01 | 0.98 (0.80-1.20) | .83 |
| Calcium, mg/dL | ||||
| 8.5-10.5 | 1 [Reference] | NA | 1 [Reference] | NA |
| ≥8.5 | 0.72 (0.66-0.79) | <.001 | 0.68 (0.58-0.79) | <.001 |
| ≥10.5 | 1.37 (1.17-1.59) | <.001 | 1.56 (1.15-2.11) | .003 |
| Missing | 1.08 (0.84-1.40) | .54 | 1.12 (0.75-1.67) | .59 |
| Sodium, mEq/L | ||||
| 135-145 | 1 [Reference] | NA | 1 [Reference] | NA |
| <135 | 1.32 (1.23-1.43) | <.001 | 1.25 (1.10-1.43) | <.001 |
| >145 | 0.95 (0.77-1.16) | .59 | 1.07 (0.74-1.55) | .72 |
| Missing | 1.04 (0.73-1.48) | .82 | 0.97 (0.58-1.65) | .92 |
Abbreviations: BMI, body mass index; HR, hazard ratio; NA, not applicable; WBC, white blood cell.
SI conversion factors: To convert albumin to grams per liter, multiply by 10; alkaline phosphatase to microkatals per liter, multiply by 0.0167; calcium to millimoles per liter, multiply by 0.25; creatinine to micromoles per liter, multiply by 88.4; hemoglobin to grams per liter, multiply by 10.0; sodium to millimoles per liter, multiply by 1.0; WBC count to × 109 per liter, multiply by 0.001.
a
The reference range for creatinine is 0.6 to 1.2 mg/dL for men and 0.5 to 1.1 mg/dL for women.
b
The reference range for hemoglobin is 13.5 to 17.5 g/dL for men and 12.0 to 15.5 g/dL for women.