Whether or not a lung nodule 4mm will go away cannot be generalized, the most common causes of lung nodules are lung infections, pulmonary nodular disease, tuberculosis or old lesions in the lungs, and very rarely, malignant tumors in the lungs. In this case, if it is a lung infection, pulmonary nodular disease or tuberculosis, it is possible that it will disappear. If it is a malignant tumor of the lungs, it will gradually get bigger, so it is not possible to generalize whether a lung nodule 4mm will disappear. If you consider it to be an infectious lesion, you can take anti-infective treatment for two weeks and then go for a review. If it is indeed an infectious disease, it may become smaller or even disappear. Lung nodular disease will disappear in some patients even without treatment. If the tuberculosis is only 4mm, there are no symptoms and it is not easy to find out early, and it will also be cured by itself if the resistance is strong enough. If it is a malignant tumor of the lungs, it may gradually increase in size, so follow-up and regular review may be necessary under the guidance of a doctor.