TNM staging
Pronunciation: T-N-M
Also written as: TNM — Tumor, Node, Metastasis
The internationally standardized system for describing cancer extent using tumor size, lymph node involvement, and metastasis status.
Full Definition
The TNM classification system evaluates three key components: T (primary tumor characteristics), N (regional lymph node involvement), and M (distant metastasis presence). Each component receives specific designations (T1-4, N0-3, M0-1) that combine to determine overall stage groupings (Stage I-IV). This system provides universal language for cancer staging across institutions and guides treatment decisions, prognosis discussions, and research protocols. Editorial consistency requires proper capitalization and formatting of TNM designations.
Usage
Usage note: Always capitalize T, N, M; use arabic numerals for staging designations (T1, not T-1).
In Context
- "Final TNM staging revealed T3N1M0 moderately differentiated adenocarcinoma." — Pathology report
- "The tumor was upstaged to T4 based on adjacent organ invasion." — Multidisciplinary conference note