Table 2.
FAPI and FET PET imaging interpretation & follow up data
| Patient | MRI findings | FET*** PET | FAPI PET | Diagnosis | Follow-up | ||
|---|---|---|---|---|---|---|---|
| T1 post-contrast | Perfusion | BT-RADS | |||||
| 1 | Nodular enhancement | Hyper | 3C** | 2.9 | Positive | Recurrence | Re-surgery, HPR—Grade IV GBM |
| 2 | Nodular enhancement | Hyper | 3C | 4.07 | Positive | Recurrence | Salvage TMZ |
| 3 | Irregular enhancement “Swiss cheese” pattern | Iso | 3B* | 2.5 | Negative | Post-treatment changes | Follow-up MRI—no change |
| 4 | Nodular enhancement | Hyper | 3B | 3.6 | Positive | Recurrence | Salvage TMZ |
| 5 | Nodular enhancement | Iso | 3B | 5.9 | Positive | Recurrence | On Bevacizumab |
| 6 | Nodular enhancement “Swiss cheese” pattern | Hyper | 3C | 4.0 | Positive | Recurrence | Salvage TMZ |
BT-RADS 3B*: indeterminate mix of treatment effect and tumor progression [13]; BT-RADS 3C**: tumor progression favored [13]; FET PET***: tumor-to-white mater cut-off of 2.62 to differentiate between recurrence and post treatment changes [8]; HPR: histopathology report; GBM: glioblastoma; TMZ: temozolamide; MRI: magnetic resonance imaging; FAP: fibroblast-activated protein; FET: fluoro-ethyl tyrosine