Table 1 GISTs risk classification of NIH (2008)
Risk category | Tumor size (cm) | Mitotic index (per 50 HPFs) | Primary tumor site |
|---|---|---|---|
Very low risk | < 2.0 | ≤5 | Any |
Low risk | 2.1–5.0 | ≤5 | Any |
Intermediate risk | 2.1–5.0 | > 5 | Gastric |
< 5.0 | 6–10 | Any | |
5.1–10.0 | ≤5 | Gastric | |
High risk | Any | Any | Tumor rupture |
> 10 | Any | Any | |
Any | > 10 | Any | |
> 5 | > 5 | Any | |
2.1–5.0 | > 5 | Nongastric | |
5.1–10.0 | ≤5 | Nongastric |