Lung cancer can present with different symptoms. Sometimes, although rarer (<20%), it may remain asymptomatic. Among the most frequent symptoms:

- Cough
- Hemoptysis or the coughing up of blood
- Dyspnea or subjective feeling of breathing difficulty, so-called ‘hungry for air’
- Weight loss
- Thoracic pain manifesting if the tumor invades a chest cavity structure or pleura
- Asthenia or fatigue
Most lung cancer diagnoses occur when the tumor has already grown, has taken up some space and interfered with surrounding structures.
Some cancer cells can break away from the main mass grown in the lungs and travel to other body parts via the blood or lymphatic circulation. More frequently, they end up in:
- lymph nodes
- other parts inside the Lung
- bones
- brain
- liver
- adrenal glands (located above the kidneys)
Therefore, other symptoms that may also present include:
- bone pain
- stomach ache
- backache
- headache or other neurological deficits (balance, speech, walking, etc.)
In rare cases, lung cancer can release hormones that may lead to an imbalance in the body such as a decrease in Sodium or an increase in Calcium.