There are many causes of pulmonary nodules, ranging from inflammation, tuberculosis and benign nodules to malignant nodules. If the nodules are benign, they are usually not prone to cancer. Benign nodules are actually not cancerous, like the most common inflammatory nodules, which can usually be eliminated with active anti-infection treatment, and some patients can shrink or eliminate them on their own without treatment. For tuberculous nodules, they can shrink or disappear through anti-tuberculosis treatment. Some tuberculous nodules, although not treated, may calcify. Some granulomatous nodules will continue to grow, but they are usually not cancerous. There is no exact answer to whether a nodule is cancerous or not. Some inflammatory nodules that are there for a long time may lead to cancer, but this is a long process that may take five or ten years, and there is no standard answer. There is no answer as to how long it takes for a lung nodule to become cancerous. It is possible that the nodule will not become cancerous for life, but if the nodule is prone to mutation, it may become cancerous, and it may take only a few months, so if you have a nodule, you should actively review it regularly if the nature is not clear.