EOD Primary Tumor
Notes
**Note 1:** **Cortex of the bone** * The cortex of a bone is the dense outer shell that provides strength to the bone; the spongy center of a bone is the cancellous portion. * The periosteum of the bone is the fibrous membrane covering of a bone that contains the blood vessels and nerves; the periosteum is similar to the capsule on a visceral organ. **Note 2:** **Number of pelvic segments** * The number of pelvic segments involved by the primary tumor determines the appropriate EOD Primary Tumor (codes 100 through 550). The four pelvic segments used in these codes are: * Acetabulum * Iliac wing * Pubic ramus/Symphysis/Ischium * Sacrum| Code | Description | SS2018 T |
|---|---|---|
| 100 | Any size tumor - One pelvic segment involved AND no extraosseous extension | L |
| 200 | Code 100 WITH extraosseous extension - Beyond periosteum to surrounding tissues, including adjacent skeletal muscle(s) | RE |
| 300 | Any size tumor - Two pelvic segments involved AND no extraosseous extension | L |
| 400 | Code 300 WITH extraosseous extension - Beyond periosteum to surrounding tissues, including adjacent skeletal muscle(s) | RE |
| 500 | At least three pelvic segments involved, NOS | L |
| 550 | Code 500 WITH extraosseous extension - Beyond periosteum to surrounding tissues, including adjacent skeletal muscle(s) | RE |
| 600 | Confined to pelvis, NOS * Number of segments involved not known Localized, NOS | L |
| 650 | Sacroiliac joint Sacral neuroforamen | D |
| 700 | Encasement of external iliac vessels | D |
| 750 | Gross tumor thrombus in major pelvic vessels Further contiguous extension | D |
| 800 | No evidence of primary tumor | U |
| 999 | Unknown; extension not stated Primary tumor cannot be assessed Not documented in medical record Death Certificate Only | U |