Table 2. Diagnostic performance for mean kurtosis and diffusion coefficients from DKI and ADC from DWI in detecting pCR.
| Factor | Sensitivity (%) | Specificity (%) | PPV (%) | NPV (%) | Accuracy (%) | AUC* | Optimal Cutoff† |
|---|---|---|---|---|---|---|---|
| Pre-CRT | |||||||
| ADC | 57.1 (8/14) | 69 (29/42) | 38.1 (8/21) | 82.9 (29/35) | 66.1 (37/56) | 0.583 [0.44-0.71] | 0.8178 |
| MD | 64.3 (9/14) | 61.9 (26/42) | 36 (9/25) | 83.9 (26/31) | 62.5 (35/56) | 0.587 [0.45-0.72] | 1.4505 |
| MK | 92.9 (13/14) | 81 (34/42) | 61.9 (13/21) | 97.1 (34/35) | 83.9 (47/56) | 0.901 [0.79-0.97] | 0.8199 |
| Post-CRT | |||||||
| ADC | 92.9 (13/14) | 66.7 (28/42) | 48.1 (13/27) | 96.6 (28/29) | 73.2 (41/56) | 0.823 [0.70-0.91] | 1.1665 |
| MD | 92.9 (13/14) | 71.43 (30/42) | 52 (13/25) | 96.8 (30/31) | 76.8 (43/56) | 0.871 [0.75-0.95] | 2.0326 |
| MK | 92.9 (13/14) | 83.3 (35/42) | 65 (13/20) | 97.2 (35/36) | 85.7 (48/56) | 0.908 [0.80-0.97] | 0.6196 |
| Ratio | |||||||
| ADC | 78.6 (11/14) | 73.81 (31/42) | 50 (11/22) | 91.2 (31/34) | 75 (42/56) | 0.793 [0.66-0.89] | 0.4321 |
| MD | 85.7 (12/14) | 71.4 (30/42) | 45.5 (10/22) | 88.2 (30/34) | 71.4 (40/56) | 0.825 [0.70-0.91] | 0.3439 |
| MK | 71.4 (10/14) | 50 (21/42) | 32.3 (10/31) | 84 (21/25) | 55.4 (31/56) | 0.546 [0.41-0.68] | 0.2343 |
Note.—Data are percentages, with numerators and denominators in parentheses.
*Data in square brackets are 95% CIs.
†Cutoff values were obtained by calculating the maximal Youden index: Youden index = sensitivity - (1- specificity).
PPV=Positive Predictive Value, NPV=Negative Predictive Value, AUC=Area Under the ROC Curve