Lung nodule 20mm with rough edges is not necessarily lung cancer, we suggest the patient to continue to observe the condition, if the condition continues to deteriorate or the patient shows malignancy after pathological examination, then it is lung cancer. If the pathological result is not malignant, it may be caused by pneumonia, tuberculosis and other diseases. The presence of a lung nodule 20mm with rough edges when the patient undergoes imaging examination is not necessarily lung cancer. The patient should observe the condition further. If the nodule grows rapidly in a short period of time, the degree of malignancy is relatively high. The patient should go to the hospital for pathologic examination in time. If the pathological result shows malignant tumor, it may be lung cancer. In addition, the nodule belongs to the proliferative disease of the lung, if the patient has the symptom that the examination result is a pulmonary nodule 20mm with hairy edges, and the pathological examination is not malignant, it may also be caused by pneumonia, tuberculosis and other diseases. When the patient’s imaging results show that the edge of lung nodule 20mm is hairy, it is recommended that the patient follow up on time and under the guidance of the doctor to carry out formal examination to determine whether it is lung cancer.