Background
Methods
Patients
18F-FDG PET/CT scan acquisition and analysis
Texture feature | Early scan median value—all tumours (range) | Late scan median value—all tumours (range) | ↑ or ↓ (all tumours) |
p value early vs late (all tumours) | Correlation early vs late—all tumours (r and (p) values) | ↑ or ↓ (benign) |
p value early vs late (benign) | ↑ or ↓ (malignant) |
p value early vs late (malignant) |
---|---|---|---|---|---|---|---|---|---|
First-order texture features | |||||||||
ROI: mean | 6226.9 (918.2–4039.2) | 5773.3 (2646.8–55066.4) | – | 0.19 | 0.81 (<0.001) | ↓ | 0.011 | – | 0.8 |
ROI: maximum | 12881.2 (3571.6–120766.4) | 15689.9 (4654.7–221719.7) | ↑ | 0.02 | 0.86 (<0.001) | – | 0.15 | – | 0.081 |
ROI: minimum | 1906.4 (157.1–15271.0) | 1119.8 (154.7–15198.9) | ↓ | 0.001 | 0.53 (<0.001) | ↓ | 0.001 | – | 0.19 |
ROI: range | 11757.5 (2135.7–119645.4) | 14371.1 (2848.3–220643.8) | ↑ | 0.002 | 0.87 (<0.001) | ↑ | 0.01 | ↑ | 0.043 |
ROI: standard deviation | 2177.4 (444.2–19219.2) | 2199.0 (502.3–26481.3) | ↑ | 0.015 | 0.86 (<0.001) | – | 0.11 | – | 0.076 |
ROI: skewness | 0.95 (−0.93–4.54) | 3.04 (0.25–13.3) | ↑ | <0.001 | 0.05 (0.7) | ↑ | <0.001 | ↑ | <0.001 |
ROI: kurtosis | 5.5 (3.7–26.2) | 15.6 (10.1–71.1) | ↑ | <0.001 | 0.4 (0.003) | ↑ | <0.001 | ↑ | <0.001 |
ROI: coefficient of variation | 0.57 (0.26–1.14) | 1.72 (0.73–3.31) | ↑ | <0.001 | 0.65 (<0.001) | ↑ | <0.001 | ↑ | <0.001 |
ROI: median | 5895.6 (833.1–37490.6) | 5324.8 (2425.3–50631.2) | – | 0.07 | 0.79 (<0.001) | ↓ | 0.002 | – | 0.98 |
ROI: 10th percentile | 3822.0 (506.6–18913.7) | 2692.1 (1295.6–24466.4) | ↓ | 0.002 | 0.63 (<0.001) | ↓ | <0.001 | – | 0.35 |
ROI: 25th percentile | 4787.5 (637.2–24843.1) | 3966.1 (1817.0–33982.6) | ↓ | 0.008 | 0.72 (<0.001) | ↓ | <0.001 | – | 0.69 |
ROI: 75th percentile | 7148.3 (1074.9–52427.0) | 7174.7 (3026.9–71854.5) | – | 0.44 | 0.85 (<0.001) | ↓ | 0.041 | – | 0.69 |
ROI: 90th percentile | 8691.3 (1414.5–68876.1) | 8656.2 (3444.4–94054.6) | – | 0.97 | 0.87 (<0.001) | – | 0.17 | – | 0.38 |
ROI: entropy | 5.75 (4.51–6.01) | 5.71 (4.55–6.01) | – | 0.34 | 0.53 (<0.001) | – | 0.98 | – | 0.12 |
ROI: energy | 0.0038 (0.0028–0.0397) | 0.004 (0.0027–0.013) | – | 0.53 | 0.52 (<0.001) | – | 0.83 | – | 0.20 |
ROI: LoG entropy 1_5 | 5.12 (4.12–5.44) | 5.02 (3.87–5.43) | ↓ | 0.002 | 0.6 (<0.001) | ↓ | 0.016 | ↓ | 0.033 |
ROI: LoG entropy 2_0 | 5.14 (4.22–5.44) | 5 (3.87–5.41) | ↓ | 0.004 | 0.57 (<0.001) | – | 0.052 | ↓ | 0.04 |
ROI: LoG entropy 2_5 | 5.15 (4.39–5.49) | 5.11 (4.05–5.49) | – | 0.071 | 0.61 (<0.001) | – | 0.39 | – | 0.063 |
Metabolic active volume (cm3) | 35.6 (3.3–303.9) | 34.9 (3.5–301.4) | – | 0.069 | 0.89 (<0.001) | – | 0.39 | – | 0.29 |
Effective diameter (cm) | 4.08 (1.84–8.34) | 4.05 (1.98–8.32) | – | 0.14 | 0.89 (<0.001) | – | 0.59 | – | 0.29 |
SUV: mean | 1.42 (0.5–8.89) | 1.27 (0.41–9.1) | ↓ | 0.006 | 0.94 (<0.001) | ↓ | <0.001 | – | 0.89 |
SUV: total lesion glycolysis (TLG) | 62.1 (2.6–2412.7) | 47.2 (2.3–2321.5) | ↓ | 0.005 | 0.92 (<0.001) | ↓ | <0.001 | – | 0.55 |
SUV: peak | 2.5 (0.7–23.4) | 2.3 (0.7–23.3) | – | 0.93 | 0.92 (<0.001) | ↓ | 0.032 | – | 0.30 |
SUV: maximum | 3.1 (0.9–30.8) | 3.5 (0.8–30.8) | ↑ | 0.036 | 0.93 (<0.001) | – | 0.72 | ↑ | 0.039 |
SUV: minimum | 0.45 (0.09–3.35) | 0.26 (0.03–3.27) | ↓ | <0.001 | 0.56 (<0.001) | ↓ | <0.001 | – | 0.15 |
SUV: range | 2.6 (0.6–30.5) | 3.2 (0.7–30.5) | ↑ | 0.002 | 0.92 (<0.001) | – | 0.079 | ↑ | 0.019 |
SUV: standard deviation | 0.45 (0.12–5.05) | 0.44 (0.12–5.12) | ↓ | 0.033 | 0.93 (<0.001) | – | 0.704 | – | 0.092 |
SUV: skewness | 0.54 (−0.52–2.54) | 0.67 (−0.01–2.92) | ↑ | 0.002 | 0.05 (0.7) | ↑ | 0.037 | ↑ | 0.014 |
SUV: kurtosis | 3.1 (2.1–14.9) | 3.4 (2.2–15.6) | ↑ | 0.003 | 0.4 (0.003) | – | 0.090 | ↑ | 0.005 |
SUV: coefficient of variation | 0.31 (0.15–0.65) | 0.38 (0.16–0.73) | ↑ | <0.001 | 0.65 (<0.001) | ↑ | 0.001 | ↑ | 0.034 |
SUV: median | 1.4 (0.5–8.4) | 1.1 (0.4–8.7) | ↓ | 0.001 | 0.92 (<0.001) | ↓ | <0.001 | – | 0.61 |
SUV: 10th percentile | 0.9 (0.3–3.9) | 0.7 (0.3–3.9) | ↓ | <0.001 | 0.74 (<0.001) | ↓ | <0.001 | – | 0.12 |
SUV: 25th percentile | 1.1 (0.4–4.9) | 0.9 (0.3–5.4) | ↓ | <0.001 | 0.84 (<0.001) | ↓ | <0.001 | – | 0.21 |
SUV: 75th percentile | 1.8 (0.6–12.3) | 1.5 (0.5–12.6) | ↓ | 0.043 | 0.95 (<0.001) | ↓ | <0.001 | – | 0.73 |
SUV: 90th percentile | 2.1 (0.7–15.8) | 1.9 (0.6–16.1) | – | 0.45 | 0.95 (<0.001) | ↓ | 0.001 | – | 0.35 |
SUV: entropy | 0.8 (0.17–2.98) | 0.81 (0.12–2.99) | ↑ | 0.033 | 0.85 (<0.001) | – | 0.3 | – | 0.092 |
SUV: energy | 0.5 (0.06–0.92) | 0.5 (0.05–0.95) | – | 0.053 | 0.83 (<0.001) | – | 0.13 | – | 0.17 |
Second-order texture features | |||||||||
GLCM: autocorrelation | 202.1 (50.8–432.5) | 152.6 (29.6–295.2) | ↓ | <0.001 | 0.26 (0.6) | ↓ | 0.003 | ↓ | 0.026 |
GLCM: cluster prominence | 39992.1 (74471.1–118471.8) | 33630.5 (4478.5–113080.7) | – | 0.23 | 0.64 (<0.001) | – | 0.2 | – | 0.73 |
GLCM: cluster shade | 541.9 (−305.0–2242.1) | 630.5 (−85.7–2134.6) | – | 0.13 | 0.44 (0.001) | – | 0.32 | – | 0.19 |
GLCM: contrast | 36.3 (8.4–140.1) | 41.2 (5.4–146.2) | – | 0.39 | 0.58 (<0.001) | – | 0.17 | – | 0.86 |
GLCM: correlation | 0.99 (0.96–0.99) | 0.98 (0.95–0.99) | ↓ | 0.01 | 0.68 (<0.001) | – | 0.31 | ↓ | 0.001 |
GLCM: difference entropy | 2.56 (1.87–3.14) | 2.62 (1.66–3.12) | – | 0.83 | 0.57 (<0.001) | – | 0.47 | – | 0.71 |
GLCM: difference variance | 36.3 (8.4–140.1) | 41.2 (5.4–146.2) | – | 0.39 | 0.58 (<0.001) | – | 0.17 | – | 0.86 |
GLCM: dissimilarity | 4.71 (2.05–10.04) | 5.04 (1.59–11.24) | – | 0.93 | 0.6 (<0.001) | – | 0.32 | – | 0.42 |
GLCM: energy | 0.020 (0.008–0.06) | 0.023 (0.007–0.1) | ↑ | 0.016 | 0.5 (<0.001) | ↑ | 0.033 | – | 0.25 |
GLCM: entropy | 5.83 (4.39–6.34) | 5.79 (4.17–6.44) | ↓ | 0.016 | 0.47 (<0.001) | – | 0.090 | – | 0.097 |
GLCM: homogeneity | 0.73 (0.53–0.89) | 0.73 (0.5–0.91) | – | 0.30 | 0.67 (<0.001) | – | 0.12 | – | 0.80 |
GLCM: information measure correlation 1 | −0.06 (−0.15--0.01) | −0.05 (−0.17--0.01) | – | 0.069 | 0.69 (<0.001) | ↑ | 0.047 | – | 0.48 |
GLCM: information measure correlation 2 | 0.99 (0.96–0.99) | 0.98 (0.95–0.99) | ↓ | 0.005 | 0.62 (<0.001) | – | 0.23 | ↓ | 0.002 |
GLCM: inverse difference moment | 0.73 (0.53–0.89) | 0.73 (0.5–0.91) | – | 0.30 | 0.67 (<0.001) | – | 0.12 | – | 0.80 |
GLCM: inverse difference moment normalised | 0.9992 (0.9974–0.9998) | 0.9992 (0.9965–0.9998) | – | 0.91 | 0.7 (<0.001) | – | 0.31 | – | 0.28 |
GLCM: inverse difference normalised | 0.98 (0.96–0.99) | 0.98 (0.96–0.99) | – | 0.48 | 0.68 (<0.001) | – | 0.17 | – | 0.59 |
GLCM: maximum probability | 0.05 (0.02–0.13) | 0.05 (0.01–0.2) | – | 0.081 | 0.42 (0.001) | – | 0.15 | – | 0.36 |
GLCM: sum average | 27.7 (13.1–40.9) | 23.1 (9.8–33.5) | ↓ | <0.001 | 0.22 (0.1) | ↓ | 0.001 | ↓ | 0.026 |
GLCM: sum entropy | 3.71 (3.02–3.96) | 3.65 (2.88–4.0) | ↓ | 0.004 | 0.51 (<0.001) | ↓ | 0.035 | – | 0.052 |
GLCM: sum of squares variance | 221.2 (53.1–438.1) | 160.2 (30.6–313.2) | ↓ | <0.001 | 0.27 (0.046) | ↓ | 0.002 | ↓ | 0.034 |
GLCM: sum variance | 654.4 (133.8–1468.2) | 466.3 (72.8–984.9) | ↓ | 0.001 | 0.25 (0.064) | ↓ | 0.002 | ↓ | 0.028 |
GLDM: mean | 4.71 (2.05–10.04) | 5.04 (1.59–11.24) | – | 0.93 | 0.6 (<0.001) | – | 0.32 | – | 0.42 |
GLDM: entropy | 2.56 (1.87–3.14) | 2.62 (1.66–3.12) | – | 0.83 | 0.57 (<0.001) | – | 0.47 | – | 0.71 |
GLDM: variance | 13.5 (4.2–39.3) | 15.8 (2.9–64.6) | – | 0.21 | 0.59 (<0.001) | – | 0.21 | – | 0.65 |
GLDM: contrast | 36.3 (8.4–140.1) | 41.2 (5.4–146.2) | – | 0.39 | 0.58 (<0.001) | – | 0.17 | – | 0.86 |
High-order texture features | |||||||||
GLRL: short run emphasis | 0.29 (0.17–0.71) | 0.29 (0.16–0.77) | ↑ | 0.007 | 0.8 (<0.001) | – | 0.090 | ↑ | 0.034 |
GLRL: long run emphasis | 209.6 (66.8–415.0) | 164.6 (41.9–280.1) | ↓ | <0.001 | 0.22 (0.11) | ↓ | 0.003 | ↓ | 0.015 |
GLRL: grey-level nonuniformity | 8082.9 (975.1–73005.3) | 7639.5 (991.0–65663.1) | – | 0.54 | 0.88 (<0.001) | – | 0.83 | – | 0.67 |
GLRL: run length nonuniformity | 917.6 (158.9–6079.5) | 947.5 (147.8–6787.9) | ↑ | 0.023 | 0.87 (<0.001) | – | 0.10 | – | 0.12 |
GLRL: run percentage | 0.91 (0.65–0.98) | 0.91 (0.59–0.99) | – | 0.17 | 0.75 (<0.001) | – | 0.24 | – | 0.53 |
GLRL: low grey-level run emphasis | 0.93 (0.76–0.98) | 0.93 (0.7–0.99) | – | 0.31 | 0.75 (<0.001) | – | 0.29 | – | 0.71 |
GLRL: high grey-level run emphasis | 40.9 (7.4–425.5) | 35.4 (7.42–315.5) | – | 0.87 | 0.86 (<0.001) | – | 0.70 | – | 0.93 |
GLRL: short run low grey-level emphasis | 0.08 (0.04–0.18) | 0.09 (0.04–0.17) | ↑ | 0.027 | 0.61 (<0.001) | – | 0.34 | ↑ | 0.024 |
GLRL: short run high grey-level emphasis | 40.0 (4.4–424.2) | 34.2 (5.5–314.2) | – | 0.94 | 0.87 (<0.001) | – | 0.80 | – | 0.95 |
GLRL: long run low grey-level emphasis | 184.9 (44.6–377.7) | 141.0 (26.0–251.9) | ↓ | <0.001 | 0.18 (0.19) | ↓ | 0.004 | ↓ | 0.021 |
GLRL: long run high grey-level emphasis | 924.6 (279.4–3387.9) | 711.4 (336.0–2341.7) | ↓ | <0.001 | 0.66 (<0.001) | ↓ | 0.003 | ↓ | 0.002 |
GLRL: intensity variability | 945001.0 (20680.9–68924026.0) | 921355.2 (22561.0–56722816.4) | – | 0.46 | 0.87 (<0.001) | – | 0.3 | – | 0.78 |
GLRL: run length variability | 92938.6 (3597.7–5739641.7) | 103541.0 (3494.2–4675872.2) | ↑ | 0.016 | 0.86 (<0.001) | ↑ | 0.008 | – | 0.28 |
GLSZM: short zone emphasis | 0.02 (0.01–0.08) | 0.02 (0.01–0.06) | – | 0.47 | 0.44 (0.001) | – | 0.41 | – | 0.93 |
GLSZM: long zone emphasis | 253.9 (126.6–384.9) | 229.9 (129.6–327.8) | ↓ | 0.015 | 0.36 (0.007) | ↓ | 0.035 | – | 0.18 |
GLSZM: intensity nonuniformity | 97.4 (22.7–654.4) | 128.9 (33.11–594.0) | – | 0.18 | 0.61 (<0.001) | – | 0.2 | – | 0.46 |
GLSZM: zone length nonuniformity | 25.6 (10.2–180.1) | 35.8 (10.2–200.0) | – | 0.28 | 0.72 (<0.001) | – | 0.34 | – | 0.65 |
GLSZM: zone percentage | 0.068 (0.018–0.313) | 0.071 (0.018–0.335) | ↑ | 0.006 | 0.79 (<0.001) | – | 0.075 | ↑ | 0.028 |
GLSZM: low-intensity zone emphasis | 0.39 (0.28–0.54) | 0.41 (0.31–0.6) | ↑ | 0.001 | 0.63 (<0.001) | ↑ | 0.001 | – | 0.29 |
GLSZM: high-intensity zone emphasis | 4108.4 (45.4–43861.1) | 4043.2 (31.4–38723.0) | ↓ | 0.049 | 0.79 (<0.001) | – | 0.63 | ↓ | 0.037 |
GLSZM: short zone low-intensity emphasis | 0.0048 (0.0016–0.0535) | 0.0053 (0.0017–0.0355) | – | 0.83 | 0.52 (<0.001) | – | 0.25 | – | 0.46 |
GLSZM: short zone high-intensity emphasis | 33.0 (1.5–3423.9) | 72.9 (0.45–4921.8) | – | 0.59 | 0.74 (<0.001) | – | 0.59 | – | 0.73 |
GLSZM: long zone low-intensity emphasis | 100.8 (56.8–150.4) | 104.3 (54.2–167.0) | – | 0.40 | 0.34 (0.11) | – | 0.59 | – | 0.51 |
GLSZM: long zone high-intensity emphasis | 599829.4 (2743.9–11949368.6) | 322428.3 (5079.9–3059584.4) | ↓ | <0.001 | 0.81 (<0.001) | ↓ | 0.001 | ↓ | 0.016 |
GLSZM: intensity variability | 231.6 (29.5–3815.9) | 353.3 (50.2–3591.3) | – | 0.19 | 0.62 (<0.001) | – | 0.18 | – | 0.57 |
GLSZM: size zone variability | 56.2 (13.8–869.2) | 101.9 (17.3–1066.3) | – | 0.26 | 0.67 (<0.001) | – | 0.19 | – | 0.69 |
NGTDM: coarseness | 7.1 (4.3–17.4) | 6.6 (4.0–15.3) | – | 0.087 | 0.79 (<0.001) | – | 0.48 | – | 0.092 |
NGTDM: contrast | 0.14 (0.02–0.59) | 0.12 (0.01–0.46) | – | 0.16 | 0.53 (<0.001) | – | 0.31 | – | 0.33 |
NGTDM: busyness | 4.2 (0.7–32.9) | 4.7 (0.8–33.3) | ↑ | 0.007 | 0.89 (<0.001) | ↑ | 0.006 | – | 0.2 |
NGTDM: complexity | 0.09 (0.01–2) | 0.11 (0–1.55) | – | 0.66 | 0.89 (<0.001) | – | 0.94 | – | 0.59 |
NGTDM: texture strength | 0.33 (0.03–1.93) | 0.35 (0.04–1.84) | – | 0.086 | 0.83 (<0.001) | – | 0.066 | – | 0.48 |
Model-based texture features | |||||||||
FD: fractal dimension mean | 3.23 (2.85–4.14) | 3.23 (2.85–4.09) | – | 0.67 | 0.87 (<0.001) | – | 0.89 | – | 0.65 |
FD: SD | 0.37 (0.2–1.31) | 0.44 (0.22–1.92) | ↑ | 0.018 | 0.74 (<0.001) | – | 0.063 | – | 0.15 |
FD: lacunarity | 0.02 (0–0.73) | 0.02 (0.01–0.63) | ↑ | 0.006 | 0.72 (<0.001) | ↑ | 0.003 | – | 0.44 |
FD: Hurst exponent | 0.33 (0.06–1.62) | 0.34 (0.03–1.69) | – | 0.73 | 0.55 (<0.001) | – | 0.21 | – | 0.39 |
FD: blanket mean | 3.91 (2.66–4.98) | 3.64 (2.65–4.89) | ↓ | 0.014 | 0.69 (<0.001) | ↓ | 0.009 | – | 0.49 |
FD: inverse | 0.31 (0.24–0.35) | 0.31 (0.24–0.35) | – | 0.85 | 0.77 (<0.001) | – | 0.83 | – | 0.99 |
Statistical methods
Results
First order | Second order | High order | Model based | Total | |
---|---|---|---|---|---|
All 54 tumours | 25/37 (12↑, 13↓) | 9/25 (1↑, 8↓) | 13/31 (7↑, 6↓) | 3/6 (2↑, 1↓) | 50/99 (22↑, 28↓) |
30 benign tumours | 22/37 (6↑, 16↓) | 7/25 (2↑, 5↓) | 8/31 (3↑, 5↓) | 2/6 (1↑, 1↓) | 39/99 (12↑, 27↓) |
24 malignant tumours | 11/37 (9↑, 2↓) | 6/25 (0↑, 6↓) | 8/31 (3↑, 5↓) | 0/6 (0↑, 0↓) | 25/99 (12↑, 13↓) |