Lung Cancer Signs and Symptoms

Lung cancer is responsible for the most cancer deaths in both men and women throughout the world, even causing more cancer-related deaths in women than breast cancer. The incidence of lung cancer is strongly correlated with cigarette smoking, with about 90% of lung cancers arising as a result of tobacco use. Uncommon before the 1930s, lung cancer incidence began to rise during the 1930s as tobacco smoking became more popular. Public education programs about the dangers of cigarette smoking and effective smoking cessation programs have led to decreases in lung cancer rates in many developing countries. Nevertheless, lung cancer remains the most common form of cancer in men worldwide and the fifth most common form of cancer in women.

Symptoms of lung cancer are varied dependent upon the exact location of the tumor and the extent of its spread. A person with lung cancer may have the following kinds of symptoms:

• No symptoms - Up to 25% of people who get lung cancer do not have any symptoms when the cancer is found. In these cases the cancer is first discovered on a routine chest x-ray or CAT scan.

• Symptoms related to the cancer - The growth of the cancer and invasion of lung tissues and surroundings may interfere with breathing, leading to symptoms such as cough, shortness of breath, wheezing, chest pain, and coughing up blood (hemoptysis). If the cancer has invaded nerves, for example, it may cause shoulder pain that travels down the outside of the arm (called Pancoast's Syndrome) or paralysis of the vocal cords leading to hoarseness. Invasion of the esophagus may lead to difficulty swallowing (dysphagia). If a large airway is obstructed, collapse of a portion of the lung may occur and cause infections (abscesses, pneumonia) in the obstructed area.

• Symptoms related to metastasis (spread to other organs) - Lung cancer that has spread to the bones may produce excruciating pain at the sites of bone involvement. Cancer that has spread to the brain may cause a number of neurologic symptoms that may include blurred vision, headaches, seizures, or symptoms of stroke.

• Paraneoplastic symptoms - Lung cancers frequently are accompanied by so-called paraneoplastic syndromes that result from production of hormone-like substances by the tumor cells. A common paraneoplastic syndrome associated with one type of lung cancer is the production of a hormone called adrenocorticotrophic hormone (ACTH) by the cancer cells, leading to oversecretion of the hormone cortisol by the adrenal glands (Cushing's Syndrome).

• Nonspecific symptoms - Non-specific symptoms seen with many cancers including lung cancers include weight loss, weakness, and fatigue.

Always consult a doctor if you develop the symptoms associated with lung cancer, in particular, if you notice:

• A new persistent cough or worsening of an existing chronic cough
• Blood in your sputum
• Persistent bronchitis or repeated respiratory infections
• Chest pain
• Unexplained weight loss and/or fatigue
• Breathing difficulties such as shortness of breath or wheezing

For additional information, please read our Lung Cancer article.