Late stage tuberculosis is not lung cancer. Tuberculosis is a tubercle bacillus infecting the lungs and forming a mass lesion in the lung tissues, which is also manifested as a mass in the lungs in CT and X-ray chest radiographs, which is easily confused with lung cancer and other malignant tumors of the lungs. However, whether it is early or late, tuberculosis is a bacterial infectious lesion, and compared with malignant lesions such as lung cancer, it has a benign development, not only grows slowly, but also is not unlimited growth, and metastasis to distant organs will not occur even in the late stage. In a few cases, severe tuberculosis may also spread from the lungs to organs such as bones, kidneys, and lymph nodes, where tuberculosis foci also form, but this cannot be called metastasis. Pathologic examination can accurately distinguish between tuberculosis and lung cancer, because the pathologic manifestation of lung cancer is heaps of cancer cells clustered together, whereas in the case of tuberculosis, even in the advanced stage under the microscope, it shows caseous necrosis with no cellular components, and the difference between the two is very obvious. The treatment is also different, as tuberculosis adopts multi-drug combination chemotherapy, but even for advanced tuberculosis, as long as regular treatment is given, there is a great hope for a complete cure, while the possibility of a complete cure for advanced lung cancer is very slim.