11. Persistent Cough

As our lungs are responsible for helping us breath properly, a cough could point to lung cancer. We cough because our body is trying to get rid of unwanted substances, which is why it happens when we have the flu or something similar. This usually gets better with time and medication.

But if the cough persists, and you start spitting up blood, it could be cause for concern. This kind of cough is also hoarse-sounding and painful at times. Excessive coughing is also a common sign in laryngeal or thyroid cancers.