Study population
A total of 108 patients were included in the current study (80 males, 28 females; mean age, 69.0 (21–87) years). The METAVIR fibrosis grade according to FibroScan was F1, F2, F3, and F4 in 2, 36, 39, and 17 of the 94 patients, respectively. The HCC patients mean (range) FIB-4 index was 4.27 (0.3–13.7), and the mean (range) M2BPGi level was 2.79 (0.29–8.75). Among the 108 total subjects, a sustained virological response (SVR) was seen in 74 patients, and failure to achieve sustained virological response (non-SVR) was observed in 20 patients (Table 1). SVR status was determined by blood test before surgery. Details on non-SVR are shown in Table 2 (Table 2).
Box plots of Fibroscan, VTQ, Fib4-index and M2BPGi
The box plots of the METAVIR scores with respect to each method are shown in Figure 1 (Figure 1). According to Spearman's rank correlation analysis, positive correlations between each method and the METAVIR fibrosis stage were observed (FibroScan: r=0.61, p≤0.001 (Figure 1a); VTQ: r=0.64, p≤0.001 (Figure 1b); FIB-4 index: r=0.40, p≤0.001 (Figure 1c); and M2BPGi: r=0.32, p=0.01 (Figure 1d)). The median METAVIR scores for each method were as follows: FibroScan, F0: 3.9, F1: 7.6, F2: 8.8, F3: 13.1, F4: 22.8; VTQ, F0: 1.03, F1: 1.22, F2: 1.38, F3: 1.88, F4: 2.42; FIB-4 index, F0: 1.27, F1: 3.60, F2: 2.78, F3: 4.20, F4: 4.04; M2BPGi, F0: 0.55, F1: 1.40, F2: 1.71, F3: 2.37, F4: 3.60. Among the four methods, VTQ had the best correlation with the METAVIR score (r=0.64, p<0.001), followed by FibroScan (r=0.61, p≤0.001). The results for the non-SVR group are shown in Figure 2 (Figure 2). According to Spearman's rank correlation analysis, positive correlations between each method and the METAVIR fibrosis stage were observed (FibroScan: r=0.65, p≤0.001 (Figure 2a); VTQ: r=0.70, p≤0.001 (Figure 2b); FIB-4 index: r=0.44, p≤0.001 (Figure 2c); and M2BPGi: r=0.31, p=0.01 (Figure 2d)). The median METAVIR scores for each method were as follows: FibroScan, F0: 3.9, F1: 9.6, F2: 8.9, F3: 13.6, F4: 22.0; VTQ, F0: 1.03, F1: 1.25, F2: 1.40, F3: 1.89, F4: 2.39; FIB-4 index, F0: 1.27, F1: 5.99, F2: 4.18, F3: 4.88, F4: 6.05; M2BPGi, F0: 0.55, F1: 1.50, F2: 1.90, F3: 2.37, F4: 3.53.
ROC analysis of Fibroscan, VTQ, Fib4-index and M2BPGi
The sensitivity, specificity and cut-off values were compared among the four diagnostic methods. The ROC curves for each method are shown in Figure 3 (Figure 3). The areas under the ROC curve (AUC) for a diagnosis of fibrosis grade F2 or greater were as follows: 0.94 for FibroScan, 0.89 for VTQ, 0.85 for theFIB-4 index, and 0.77 for the M2BPGi level (Figure 3a). The respective values for a diagnosis of grade F3 or greater were 0.85, 0.84, 0.74, and 0.73 (Figure 3b), and those for a diagnosis of F4 were 0.91, 0.88, 0.67, and 0.78 (Figure 3c). The results of the non-SVR group are shown in Figure 4 (Figure 4). The AUC for a diagnosis of fibrosis grade F2 or greater were as follows: 0.95 for FibroScan, 0.93 for VTQ, 0.87 for the FIB-4 index, and 0.81 for the M2BPGi level (Figure 4a). The respective values for a diagnosis of grade F3 or greater were 0.85, 0.83, 0.67, and 0.67 (Figure 4b), and those for a diagnosis of F4 were 0.89, 0.86, 0.65, and 0.76 (Figure 4c).
The cutoff values for each test for a diagnosis of grade F2 or greater were as follows: FibroScan, 6.2; VTQ, 1.27; FIB-4 index, 1.74; M2BPGi, 1.40. The respective values for a diagnosis of F3 or greater were 8.9, 1.46, 2.91, and 1.76, and those for a diagnosis of F4 were 15.0, 1.94, 3.25, and 2.70. (Table3)The results of the non-SVR group were as follows: FibroScan, 5.6; VTQ, 1.26; FIB-4 index, 1.74; M2BPGi, 1.63. The respective values for a diagnosis of F3 or greater were 9.8, 1.78, 3.20, and 2.15, and those for a diagnosis of F4 were 16.0, 1.94, 4.56, and 2.70. The cutoff value was taken as the maximum value of [sensitivity + specificity - 1] (Table4).