Extranodal Extension
Tumor growth extending beyond the capsule of lymph nodes into surrounding soft tissues, indicating advanced local disease.
Full Definition
The pathologic finding where malignant cells have breached the fibrous capsule of involved lymph nodes and invaded into adjacent soft tissues, fat, or other structures. This finding represents a more advanced form of nodal involvement compared to intranodal disease confined within the lymph node capsule. Extranodal extension has significant prognostic implications across various cancer types, particularly in head and neck cancers where it affects staging, treatment planning, and survival outcomes. The presence of extranodal extension typically upstages the nodal category in TNM staging systems and may influence decisions regarding adjuvant therapy intensity. Radiologically, it may be suggested by irregular nodal borders, infiltration of perinodal fat, or soft tissue masses contiguous with lymph nodes.
Usage
Usage note: May be abbreviated as ENE in clinical documentation; extracapsular extension is an acceptable synonym.
In Context
- "Histopathologic examination revealed extranodal extension involving the surrounding adipose tissue." — Surgical pathology report
- "The presence of extranodal extension upstaged the patient to pN3 disease." — Staging summary