Coughing blood
When lung cancer starts to impact the lung tissues, you start to cough up blood. The by-the-book definition of this symptom is hemoptysis.
The blood can be rust-colored, clotted, or may look like pink or red streaks in the mucus. You’re probably asking yourself: When do I know if it’s time to go to the doctor?
Well, you should call the doctor right away if you’re coughing up more than half a cup(100 milliliters) of bloody mucus, as this is an alarming symptom and things can rapidly worsen. Also, if it’s been more than a week since you started coughing up blood, this also qualifies as a reason to get checked.