Definition of Pathologic and Metabolic Grading in This Study
| Pathologic | Metabolic | ||
| Grade | Ki-67 index | Grade | T/L SUV ratio* |
| pG1 | ≤2% | mG1 | <1 |
| pG2 | 3–20% | mG2 | 1–2.3 |
| pG3 | >20% | mG3 | >2.3 |
↵* T/L ratio of SUVmax.
Pathologic grading is according to TNM staging and grading system for NET; metabolic grading is proposal according to 18F-FDG PET/CT (own data).