Table 6.
Comparison of DPD Screening Approaches to Correctly Predict Grade 3 or Higher FP Toxicity.
| Statistical property | Genotyping | Phenotyping Uracil ≥ 16 ng/ml | Phenotyping UH2/U ratio | Multi-parametric method |
|---|---|---|---|---|
| N | 472 | 472 | 472 | 472 |
| False Positives, n (%) | 10 (2.1%) | 34 (7.2%) | 6 (1.3%) | 10 (2.1%) |
| False Negatives, n (%) | 178 (36.4%) | 108 (22.9%) | 67 (14.2%) | 12 (2.5%) |
| Sensitivity (%) | 33.08 | 59.40 | 74.81 | 95.49 |
| Specificity (%) | 95.15 | 83.50 | 97.09 | 95.15 |
| Positive Predictive Value (%) | 89.80 | 82.29 | 97.07 | 96.21 |
| Negative Predictive Value (%) | 52.41 | 61.43 | 74.91 | 94.23 |
| Positive Likelihood ratio (LR+) | 6.82 | 3.59 | 25.68 | 19.67 |
| Negative Likelihood ratio (LR-) | 0.70 | 0.48 | 0.26 | 0.047 |
| Diagnostic Odds Ratio (DOR) | 9.69 | 7.48 | 98.76 | 418.51 |
| Clinical Diagnostic Strength | Moderate | Moderate | Moderately Strong | Very Strong |
|
Deaths
(Grade 5 Toxicity) |
Genotyping |
Phenotyping
Uracil ≥ 16 ng/ml |
Phenotyping
UH2/U ratio |
Multi-Parametric Method |
| N | 41 | 41 | 41 | 41 |
| Sensitivity, n (%) | 20 (48.78%) | 33 (80.5%) | 37 (90.2%) | 40 (97.6%) |
| False negatives, n (%) | 21 (51.2%) | 8 (19.5%) | 4 (9.8%) | 1 (2.4%) |
“-” = not applicable