Fig. 2From: Lung cancer in the emergency departmentLung cancer staging. T refers to the primary tumor size and ranges from no primary tumor (T0) to a tumor more than 7Â cm in the greatest dimension (T4). N describes regional lymph node involvement and broadly includes no regional lymph node involvement (N0) to contralateral mediastinal, hilar, scalene, or supraclavicular or ipsilateral scalene or supraclavicular lymph node metastasis (N3). The presence of distant metastasis is categorized as M0 (no distant metastasis) and M1 (distant metastasis). M1 is further delineated into subclasses where M1a consists of secondary nodules in the contralateral lung, pericardium, or pleura, with or without the presence of a malignant pleural or pericardial effusion. M1b involves one extra-thoracic metastasis, and M1c accounts for multiple extra-thoracic metastases. Information derived from [96]Back to article page