Table 2.
Overview of studies regarding the differentiation of radiation-induced changes from brain metastasis recurrence using amino acid PET
| Tsuyuguchi et al, 200380 | Terakawa et al, 200879 | Galldiks et al, 201235 | Lizarraga et al, 201482 | Cicone et al, 201583 | Minamimoto et al, 201581 | Romagna et al, 201637 | Ceccon et al, 201736 | Tomura et al, 201773 | Yomo et al, 201788 | |
|---|---|---|---|---|---|---|---|---|---|---|
| Patients, n | 21 | 51 | 31 | 32 | 42 | 39 | 22 | 62 | 15 | 32 |
| Lesions, n | 21 | 56 | 40 | 83 | 46 | 42 | 50 | 76 | 18 | 37 |
| Recurrent metastases, n | 9 | 24 | 19 | 32 | 20 | na | 21 | 36 | 10 | 19 |
| Radiation-induced changes, n | 12 | 32 | 21 | 51 | 26 | na | 29 | 40 | 8 | 18 |
| Histological confirmation of diagnosis | 52% | na | 28% | 11% | 24% | na | 40% | 34% | 56% | 46% |
| Tracer | MET | MET | FET | FDOPA | FDOPA | MET | FET | FET | MET | MET |
| Amino acid PET method | 10 min static scan, 20 min p.i. | 10 min static scan, 20 min p.i. | dynamic scan, 0–50 min, 16 frames, summed image 20–40 min p.i. | 20 min static scan, 10 min p.i. | 20 min static scan, 15 min p.i. | 10 min static scan, 20 min p.i. | dynamic scan, 0–40 min, 16 frames, summed image 10–30 min p.i. | dynamic scan, 0–50 min, 16 frames, summed images 20–40 min p.i. | static scan 20 min p.i., scan duration na | 10 min static scan, 20 min p.i. |
| Additional imaging method | na | na | na | na | DSC PWI | na | na | na | DWI, FDG PET | na |
| Sensitivity | 78% | 79% | 74% | 81% | 90% | 82% | 86% | 86% | 90% | 82% |
| Specificity | 100% | 75% | 90% | 73% | 92% | 86% | 79% | 88% | 75% | 75% |
| Accuracy | na | na | 83% | 76% | 91% | 83% | 82% | 87% | na | na |
| Threshold (TBRmean) | 1.4 | 1.4 | 2.0 | 1.7 | 1.6 (TBRmax) | 1.3 (TBRmax) | 2.0 | 2.0 | 1.4 (TBRmax) | 1.4 (TBRmax) |
| Increase of accuracy by integrating dynamic FET PET parameters | na | na | 10% | na | na | na | 6% | 1% | na | na |
| Performance of amino acid PET compared with other imaging method(s) | na | na | na | na | superior | na | na | na | superior | na |
DSC PWI = dynamic susceptibility contrast-enhanced perfusion-weighted imaging; DWI = diffusion-weighted imaging; FDG =18F-2-fluoro-2-deoxy-D-glucose; FDOPA = 3,4-dihydroxy-6-[18F]-fluoro-L-phenylalanine; FET = O-(2-[18F]fluoroethyl)-L-tyrosine; sL/GM = lesion to gray matter ratio; MET =11C-methyl-L-methionine; na = not available; p.i. = post-injection; TBRmean/max = mean or maximum standardized uptake value of the lesion divided by the maximum standardized uptake value of the reference region