Which components are used to determine the TNM classification in cancer staging?

• A. Lymph node status
• B. Tumor size, lymph nodes, and metastasis
• C. Metastasis only
• D. Tumor grade and margins

Answer: (B)

TNM staging uses three elements to describe cancer spread: T for the size and extent of the primary tumor, N for involvement of regional lymph nodes, and M for distant metastasis. These three descriptors together determine the overall stage, guiding prognosis and treatment decisions. Tumor grade and margins are important prognostic/pathology factors, but they are not part of the TNM classification itself. So, tumor size/extent, lymph node status, and presence of distant metastasis constitute the components used to determine the TNM classification.