TABLE 1.
Multivariate Cox analysis of the training set on CSS and OS
| Variables | Patient no. (%) | CSS | OS |
|---|---|---|---|
| HR (95% CI) | HR (95% CI) | ||
| Age (years) | |||
| ≤66 | 1579 (67.0) | Reference | Reference |
| 67–76 | 4797 (20.4) | 1.17 (1.12–1.22)*** | 1.15 (1.11–1.20)*** |
| ≥77 | 2977 (12.6) | 1.30 (1.24–1.37)*** | 1.34 (1.28–1.40)*** |
| Race | |||
| White | 16,389 (69.5) | Reference | Reference |
| Black | 3305 (14.0) | 0.95 (0.91–1.00)* | 0.98 (0.93–1.02) |
| Other | 3876 (16.5) | 0.87 (0.83–0.92)*** | 0.85 (0.82–0.89)*** |
| Sex | |||
| Male | 18,311 (77.7) | Reference | Reference |
| Female | 5259 (22.3) | 0.92 (0.88–0.96)*** | 0.91 (0.87–0.94)*** |
| Primary tumor number | |||
| 1 | 22,781 (96.7) | Reference | Reference |
| ≥2 | 789 (3.3) | 0.48 (0.43–0.54)*** | 0.67 (0.61–0.74)*** |
| Tumor size (mm) | |||
| ≤45 | 10,303 (43.7) | Reference | Reference |
| 46–85 | 5182 (22.0) | 1.55 (1.47–1.63)*** | 1.44 (1.37–1.50)*** |
| ≥86/unknown | 8085 (34.3) | 2.14 (2.03–2.25)*** | 1.94 (1.85–2.04)*** |
| Fibrosis score | |||
| 0–4 | 1087 (4.6) | Reference | Reference |
| 5–6 | 5575 (23.7) | 1.16 (1.06–1.28)** | 1.21 (1.11–1.33)*** |
| Unknown | 16,908 (71.7) | 1.28 (1.17–1.40)*** | 1.32(1.21–1.43)*** |
| AFP | |||
| Positive | 13,435 (57.0) | Reference | Reference |
| Negative | 4711 (20.0) | 0.62 (0.59–0.65)*** | 0.66 (0.63–0.69)*** |
| Bordline | 37 (0.2) | 0.92 (0.60–1.41) | 0.87 (0.58–1.31) |
| Unknown | 5387 (22.8) | 0.78 (0.74–0.81)*** | 0.79 (0.76–0.82)*** |
| T | |||
| 0/1 | 9396 (39.9) | Reference | Reference |
| 2 | 4725 (20.0) | 1.39 (1.32–1.46)*** | 1.29 (1.23–1.35)*** |
| 3 | 5341 (22.7) | 1.72 (1.64–1.81)*** | 1.60 (1.53–1.68)*** |
| 4 | 855 (3.6) | 1.96 (1.80–2.13)*** | 1.80 (1.66–1.95)*** |
| X | 3253 (13.8) | 1.32 (1.24–1.42)*** | 1.27 (1.19–1.35)*** |
| N | |||
| 0 | 18,909 (80.2) | Reference | Reference |
| 1 | 1642 (7.0) | 1.27 (1.20–1.35)*** | 1.26 (1.19–1.33)*** |
| X | 3019 (12.8) | 1.15 (1.07–1.23)*** | 1.14 (1.07–1.22)*** |
| M | |||
| 0 | 20,334 (86.3) | Reference | Reference |
| 1 | 3236 (13.7) | 1.62 (1.52–1.73)*** | 1.57 (1.48–1.67)*** |
| Metastasis to brain | |||
| Yes | 75 (0.3) | Reference | Reference |
| No | 21,792 (92.5) | 0.90 (0.70–1.15) | 0.91 (0.72–1.15) |
| Unknown | 1703 (7.2) | 0.93 (0.68–1.23) | 0.92 (0.67–1.25) |
| Metastasis to lung | |||
| Yes | 1299 (5.5) | Reference | Reference |
| No | 20,533 (87.1) | 0.74 (0.69–0.80)*** | 0.75 (0.70–0.81)*** |
| Unknown | 1738 (7.4) | 0.93 (0.78–1.10) | 0.91 (0.77–1.08) |
| Metastasis to bone | |||
| Yes | 955 (4.1) | Reference | Reference |
| No | 20,928 (88.8) | 0.94 (0.86–1.02) | 0.97 (0.89–1.05) |
| Unknown | 1687 (7.1) | 0.84 (0.68–1.04) | 0.88 (0.72–1.08) |
| Node | |||
| No | 21,043 (89.3) | Reference | Reference |
| Yes | 827 (3.5) | 0.86 (0.73–1.01) | 0.85 (0.73–0.98)* |
| Unknown | 1700 (7.2) | 0.74 (0.68–0.81)*** | 0.76 (0.70–0.83)*** |
| Surgery | |||
| Yes | 5301 (22.5) | Reference | Reference |
| No/unknown | 18,269 (77.5) | 3.57 (3.37–3.78)*** | 3.40 (3.23–3.58)*** |
| Surgery_lymph | |||
| Yes | 659 (2.8) | Reference | Reference |
| No/unknown | 22,911 (97.2) | 1.34 (1.09–1.65)** | 1.29 (1.06–1.55)** |
| Chemotherapy | |||
| Yes | 9744 (41.3) | Reference | Reference |
| No/unknown | 13,826 (58.7) | 1.92 (1.85–1.99)*** | 1.95 (1.88–2.01)*** |
| Cost‐of‐living index | |||
| ≤0.882 | 4822 (20.4) | Reference | Reference |
| 0.885–1.167 | 12,652 (53.7) | 0.86 (0.82–0.91)*** | 0.87 (0.83–0.92)*** |
| ≥1.169 | 6096 (25.9) | 0.78 (0.74–0.85)*** | 0.80 (0.75–0.86)*** |
| Income ($) | |||
| 22,500–60,380 | 4896 (20.8) | Reference | Reference |
| 60,460–82,200 | 11,526 (48.9) | 0.99 (0.94–1.05) | 0.98 (0.94–1.03) |
| 82,940–132,070 | 7148 (30.3) | 1.01 (0.94–1.09) | 1.02 (0.95–1.09) |
| Insurance | |||
| Medicaid | 5890 (25.0) | Reference | Reference |
| Private insured | 15,835 (67.2) | 0.93 (0.89–0.96)*** | 0.89 (0.86–0.93)*** |
| No/unknown | 1845 (7.8) | 1.22 (1.14–1.30)*** | 1.16 (1.09–1.23)*** |
| Marital | |||
| Married/domestic partner | 11,359 (48.2) | Reference | Reference |
| Other | 5507 (23.4) | 1.12 (1.07–1.16)*** | 1.12 (1.08–1.17)*** |
| Single | 5372 (22.8) | 1.07 (1.03–1.12)** | 1.10 (1.06–1.15)*** |
| Unknown | 1332 (5.6) | 0.89 (0.82–0.96)** | 0.90 (0.84–0.96)** |
| Residence | |||
| Metropolitan | 21,255 (90.2) | Reference | Reference |
| Non‐metropolitan | 2315 (9.8) | 0.99 (0.93–1.05) | 0.99 (0.93–1.04) |
| Poverty rate | |||
| 8.9%–11.6% | 6897 (29.3) | Reference | Reference |
| 11.8%–14.2% | 11,798 (50.1) | 1.00 (0.93–1.07) | 1.00 (0.94–1.07) |
| 16.3%–21.6% | 4875 (20.6) | 1.12 (1.03–1.21)** | 1.11 (1.04–1.20)** |
| Education level | |||
| 78.7%–86.7% | 14,464 (61.4) | Reference | Reference |
| 88.5%–94.6% | 9106 (38.6) | 0.98 (0.92–1.05) | 0.98 (0.93–1.05) |
Fibrosis score: AJCC classifies fibrosis scores 0–4: none to moderate fibrosis; 5–6: severe fibrosis or cirrhosis. Fibrosis score is also called Ishak score.
Node: lymph nodes removed for examination to derive the staging basis for the N category in the TNM system.
Surgery_lymph: surgery for regional lymph node.
Education level represents the percentage of patients aged ≥25 years with at least a high school diploma. The education level and poverty rate were determined at the county‐level.
Abbreviations: AFP, alpha fetoprotein; AJCC, American Joint Committee on Cancer;CI, confidence interval; CSS, cause‐specific survival; HR, hazard ratio; OS, overall survival; T, N, M, TNM staging system (T, tumor, N, node, M, metastasis).
*
p < 0.05.
**
p < 0.01.
***
p < 0.001.