The growth and division of normal cells are very orderly, and only after the old cells die, new cells will grow, which ensures the normal function of the body and also ensures that the cells will not grow excessively. Unlike cancer, the genes of cancer cells have been changed due to external or internal factors, and the growth and division of cancer cells are in a disorderly state, and their growth and division are no longer under control, and cancer cells will gradually invade or destroy the tissues around them, causing damage to normal tissue functions. If the cancer cells enter the blood or lymphatic fluid and enter other organs or tissues with the blood or lymphatic fluid, the cancer cells will again take root in these places and form new cancer tumors, which we call tumor metastasis. The so-called lung cancer is this malignant cancer cells originated from the tissue cells of the lung, and it is the genetic change of the lung cells after being influenced by the outside world. Yao Li, Department of Integrated Chinese and Western Medicine, Agricultural Third Division Hospital, Kashgar, Xinjiang, China