Table 3.
Subgroup analysis of serum carcinoembryonic antigen and carbohydrate antigen 19-9 based on the serum total bilirubin levels and the T and N stages of The American Joint Committee on Cancer staging system
| AUC | Sensitivity (%) | Specificity (%) | PPV (%) | NPV (%) | ||
|---|---|---|---|---|---|---|
| Total bilirubin | ||||||
| ≥51.3 µmol/l (n = 197) | CEA | 0.565 | 13.7 | 99.2 | 60.0 | 93.1 |
| CA19-9 | 0.820 | 69.5 | 94.5 | 51.9 | 97.3 | |
| <51.3 µmol/l (n = 447) | CEA | 0.529 | 6.5 | 99.2 | 61.7 | 84.6 |
| CA19-9 | 0.716 | 48.8 | 94.5 | 63.2 | 90.5 | |
| T stage | ||||||
| 0, I, II (n = 298) | CEA | 0.538 | 8.4 | 99.2 | 58.1 | 89.4 |
| CA19-9 | 0.707 | 47.0 | 94.5 | 52.4 | 93.3 | |
| III, IV (n = 350) | CEA | 0.540 | 8.9 | 99.2 | 63.3 | 87.8 |
| CA19-9 | 0.797 | 64.9 | 94.5 | 64.1 | 94.7 | |
| N stage | ||||||
| 0 (n = 427) | CEA | 0.541 | 8.9 | 99.2 | 67.9 | 85.5 |
| CA19-9 | 0.723 | 50.1 | 94.5 | 62.8 | 91.1 | |
| I, II (n = 218) | CEA | 0.540 | 8.7 | 99.2 | 51.4 | 92.0 |
| CA19-9 | 0.817 | 68.8 | 94.5 | 54.2 | 97.0 |
AUC, area under the curve; CA19-9, carbohydrate antigen 19-9; CEA, carcinoembryonic antigen; NPV, negative predictive value; PPV, positive predictive value.