The initial stages of lung cancer do not produce any symptoms and it normally goes unnoticed. It is increasingly common for lung cancer to be diagnosed by chance while performing an X-ray to explore another complaint. Symptoms generally appear in later phases of the disease and so most cases are only diagnosed when the cancer has reach an advanced stage.
Symptomatology depends on the size and location of the tumour. The most common symptoms include:
A chronic cough or cough that differs from normal. This is the most typical symptom; it arises because of bronchial irritation.
Shortness of breath (or dyspnoea). Caused by decreased lung capacity, the presence of the tumour or some other cause induced by the tumour, such as a thrombus obstructing a pulmonary blood vessel (pulmonary embolism) or the presence of fluid in the pleura (pleural effusion).
Blood in sputum (or haemoptysis).
Chest or shoulder pain. Pain in this region occurs when the tumour has spread towards the chest wall, pleura, ribs, muscles and nerves.
Other symptoms. Associated with lung cancer are voice disorders (dysphonia), poor appetite and weight loss, tiredness, bone and spine pain (if it has spread to bones) or headache and vomiting (if it has spread to the brain).
Nevertheless, the presence of these symptoms does not necessarily mean you have lung cancer as they may also be caused by other types of benign disease. When in doubt you should always visit your doctor who will decide whether your case needs to be studied further with some additional tests.