EOD Primary Tumor
Notes
**Note 1:** Deep invasion (code 300) is defined as either invasion beyond the subcutaneous fat, or >6 mm deep (as measured from the granular layer of adjacent normal epidermis to the base of the tumor).
**Note 2:** In the case of multiple simultaneous tumors, code the tumor with the greatest extension.
**Note 3:** Skin ulceration does not alter the classification.
| Code |
Description |
SS2018 T |
| 000 |
Carcinoma in situ |
IS |
| 100 |
Lesion(s) confined to dermis
Subcutaneous tissue (through entire dermis) |
L |
| 300 |
Bone erosion (minor or NOS)
Deep invasion
- Skeletal muscle
- Underlying cartilage
Perineural invasion |
RE |
| 400 |
Maxilla
Mandible
Orbital bone
Temporal bone |
RE |
| 500 |
Gross cortical bone/marrow |
RE |
| 600 |
Skull base invasion
Skull base foramen |
RE |
| 700 |
Further contiguous extension |
D |
| 999 |
Unknown; extension not stated
Primary tumor cannot be assessed
Not documented in patient record
Death Certificate Only |
U |
(1) Fritz AG, Ries LAG (eds). **SEER Extent of Disease 1988: Codes and Coding Instructions (3rd Edition, 1998)**, National Cancer Institute, NIH Pub. No. 98-2313, Bethesda, MD, 1998
(2) Young JL Jr, Roffers SD, Ries LAG, Fritz AG, Hurlbut AA (eds.). **SEER Summary Staging Manual-2000: Codes and Coding Instructions**, National Cancer Institute, NIH Pub. No. 01-4969, Bethesda, MD, 2001.
(3) Collaborative Stage Work Group of the American Joint Committee on Cancer. **Collaborative Stage Data Collection System User Documentation and Coding Instructions, version 02.05**. American Joint Committee on Cancer (Chicago, IL)
(4) Gress, D.M., Edge, S.B., Gershenwald, J.E., et al. **Principles of Cancer Staging**. In: Amin, M.B., Edge, S.B., Greene, F.L., et al. (Eds.) AJCC Cancer Staging Manual. 8th Ed. New York: Springer; 2017: 3-30
(5) Lydiatt, W.M., Patel, S.G., Shah, J.P., et al. **Staging Head and Neck Cancers**. In: Amin, M.B., Edge, S.B., Greene, F.L., et al. (Eds.) AJCC Cancer Staging Manual. 8th Ed. New York: Springer; 2017: 55-65
(6) Califano, J.A., Lydiatt, W.M., Shah, J.P., et al. **Cutaneous Squamous Cell Carcinoma of the Head and Neck**. In: Amin, M.B., Edge, S.B., Greene, F.L., et al. (Eds.) AJCC Cancer Staging Manual. 8th Ed. New York: Springer; 2017: 171-181
