It is not possible to talk about any difference between dry cough and lung cancer cough because dry cough, especially irritating dry cough, can itself be typical of cough caused by lung cancer. The irritating dry cough itself is just a symptom, a light cough, without sputum in most cases. The cough of lung cancer can be this irritating dry cough in many cases, which means they are not different, and the dry cough is a manifestation of the cough of lung cancer. If there is an infection at the same time, there can be this cough with phlegm. There are many causes of dry cough, such as general bronchitis, bronchial mycoplasma infection, as well as asthma, allergic airway hyperreactivity, etc. Therefore, it is unlikely to distinguish which disease it really is or whether it is lung cancer simply by the symptoms of this dry cough. If this kind of irritating dry cough is accompanied by frequent coughing out of blood, it is more likely that you should be alert to lung cancer. In addition, bronchial dilatation or tuberculosis may also have such symptoms, so you cannot judge whether it is a cough of lung cancer by this dry cough alone, but you should go to the hospital for relevant examinations, and in many cases, a general CT can clarify it.