Derived Grade
NAACCR Item
NAACCR #1975| Code | Description |
|---|---|
| 1 | G1: Tumor with areas of retinoma [retinocytoma] (fleurettes or neuronal differentiation) |
| 2 | G2: Tumor with many rosettes (Flexner-Wintersteiner or Homer Wright) |
| 3 | G3: Tumor with occasional rosettes (Flexner-Wintersteiner or Homer Wright) |
| 4 | G4: Tumor with poorly differentiated cells without rosettes and/or with extensive areas (more than half of tumor) of anaplasia |
| A | Well differentiated |
| B | Moderately differentiated |
| C | Poorly differentiated |
| D | Undifferentiated, anaplastic |
| 9 | Grade cannot be assessed (GX); Unknown |