Table 2. Optimal cut-off values under 95% confidence interval for AJCC staging according to ROC curves analysis, with p values from direct comparison of ROC curves (only positive comparisons are shown).
| AJCC stage | Cut off value | Sensitivity(%) (95% CI) | Specificity(%) (95% CI) | Pos LR(95% CI) | Neg LR(95% CI) | p value |
|---|---|---|---|---|---|---|
| D | 0.749 × 10−3 mm2/s | 73.9(58.9-85.7) | 93.1(77.9-99.2) | 10.72(2.8-41.3) | 0.28(0.2-0.5) | |
| f | 0.145 | 76.1(61.24-87.4) | 75.9(56.5-89.7) | 3.15(1.6-6.1) | 0.32(0.2-0.5) | |
| D* | 100.401 × 10−3 mm2/s | 60.9(45.4-74.9) | 96.6(82.2-99.9) | 17.65(2.5-122.8) | 0.41(0.3-0.6) | |
| Ktrans | 0.571 /min | 97.8(88.5-99.9) | 96.6(82.2-99.9) | 28.37(4.1-194.7) | 0.023(0.003-0.2) | 0.0001a,b |
| Kep | 0.8196 /min | 91.3(79.2-97.6) | 86.2(68.3-96.1) | 6.62(2.7-16.5) | 0.10(0.04-0.3) | |
| Ve | 0.6556 % | 87.0(73.7-95.1) | 89.7(72.6-97.8) | 8.41(2.9-24.7) | 0.15(0.07-0.3) | |
| Vp | 0.0757 % | 84.8(71.1-93.7) | 93.1(77.2-99.2) | 12.29(3.2-47.1) | 0.16(0.08-0.3) |
* AJCC = American Joint Committee on Cancer; CI = confidence interval; Pos LR = positive likelihood ratio; Neg LR = negative likelihood ratio “a” = Ktrans vs f; “b” = Ktrans vs D*;
Bonferroni corrected p value = 0.002.