Histology Grade Extension AJCC 6 Table
Notes
**Note**: For CS Extension codes 000, 100-550, and 950-999 ONLY, where histology equals 8020, 8021, 8030, 8031, or 8032, or grade equals 4, the T category is assigned based on the value of CS Extension as shown here.| CS Extension | T Category |
|---|---|
| 000, 950, 999 | T4NOS |
| 100, 200, 300, 400 | T4a |
| 405, 410, 415, 420, 490 | ERROR: |
| 450, 480, 500, 520, 550 | T4b |
| CS Extension | T Category |
|---|---|
| 000 | T4NOS |
| 100 | T4a |
| 200 | T4a |
| 300 | T4a |
| 400 | T4a |
| 405 | ERROR: |
| 410 | ERROR: |
| 415 | ERROR: |
| 420 | ERROR: |
| 450 | T4b |
| 480 | T4b |
| 490 | ERROR: |
| 500 | T4b |
| 520 | T4b |
| 550 | T4b |
| 950 | T4NOS |
| 999 | T4NOS |