Topic overview

Start with the big picture

Grading evaluates features such as differentiation, nuclear atypia, mitotic activity, and necrosis; lower-grade tumors are generally more differentiated and associated with a better prognosis. Staging assesses anatomic spread and is generally more important for prognosis. The TNM framework describes the primary tumor, regional lymph nodes, and distant metastasis, with stages grouped from 0 to IV. Paraneoplastic syndromes result from mechanisms such as ectopic hormone or cytokine production, immune cross-reactivity, and hypercoagulability. Examples include endocrine disturbances, neuromuscular effects, skin changes, and thrombotic complications. Some syndromes can appear before a tumor is identified, making recognition of the pattern clinically relevant.