TNM Gets an Upgrade in Eight Edition Staging Guidelines

Nearly a century ago, cancer staging was a simple categorization of disease as either local, regional, or distant. Then in the 1940s, a French surgeon developed the concept for a staging system that uses the size of the primary tumor (T), its lymphatic involvement (N), and the presence of metastases (M) to stage a patient’s cancer based on the anatomic extent of the disease at the time of diagnosis.