Does coughing up phlegm mean I have lung cancer?

A cough with phlegm can mean many things, but it is a lung cancer symptom. Most times, however, it does not mean you have lung cancer. It is a good idea to be checked by a doctor if you have this symptom.

There are many reasons why people have a cough that produces phlegm. Most new coughs are related to an irritation in the lung such as viral infection or bacterial infection; and phlegm is commonly produced in these conditions. These coughs usually improve and then completely disappear once the infection has gone away. Some people have coughs that are persistent over months or years, and these are usually related to such things as acid reflux (heartburn), irritation from smoking, asthma, chronic lung damage, exposure to irritants in the surrounding environment, or other problems unrelated to the lungs themselves. Many of these coughs are also associated with phlegm.

The production of phlegm with a cough is not related to whether a lung cancer is present. Many people who have lung cancer don't have any cough at all. In some people who develop lung cancer a new cough may appear; in other people who develop lung cancer a cough that has been bothersome for months or years may change in character, becoming harsher or more nagging. Coughs related to a lung cancer can produce blood, phlegm, or nothing at all (dry cough).