Extranodal Extension Head and Neck Pathological
**Note 1:** Physician statement of extranodal extension (ENE) pathologically during a lymph node dissection or physician pathological stage indicating the absence or presence of ENE can be used to code this data item when no other information is available.
**Note 2:** Code the status of ENE assessed on histopathologic examination of **surgically resected** involved regional lymph node(s). Do not code ENE from a lymph node biopsy (FNA, core, incisional, excisional, sentinel). Do not code ENE for any distant lymph nodes.
* If codes 0.0-0.9, X.1-X.7 are used, this indicates that the lymph nodes were surgically resected and Scope of Regional Lymph Node Surgery [NAACCR Data Item: 1292] must be 3-7
**Note 3:** Be aware that the rules for coding ENE for head and neck sites compared to non-head and neck sites are different.
**Note 4:** Definitions of ENE subtypes and rules:
* Microscopic ENE [ENE (mi)] is defined as less than or equal to 2 mm.
* Major ENE [ENE (ma)] is defined as greater than 2 mm.
* Both ENE (mi) and ENE (ma) qualify as ENE (+) for definition of pN.
**Note 5:** The measurement of ENE is the distance from the lymph node capsule in millimeters (mm).