The great majority of lung cancers originate within the walls of the bronchi, the three-like structures of tubes which carry air to the lungs. That is why lung cancers are more correctly know as bronchogenic cancers. The direct cause of this form of cancer, like all other cancers, is unknown. However, there is much evidence to show that cigarette smoking is responsible factor, as well as inhalation of certain irritating dusts (including cobalt and chromates) and fumes. Lung cancer cases have increased, and now account for about 15% of all cancers. The disease occurs in middle life or later, with greater frequency in men.
Symptoms. Symptoms vary with the size and location of the tumor. The patient develops a cough early in the illness. It is usually dry but there may be blood in the mucus. There is chest pain similar to that of pleurisy . The patient is often short of breath and wheezes as he breathes. His finger joints swell painfully. There can be swelling of the face and upper extremities, and swallowing difficulties, depending upon where the tumor located.
Complications. Complications include collapse of the lung, recurrent pneumonias, bronchiectasis, and lung abscess. However, the real danger is the fatal spread of this tumor to other parts of the body.
Prevention. The main hope is to identify the tumor before the symptoms appear. For that reason, all men over 40, and particularly those who smoke, should have routine chest X rays. A patient who has a persistent cough, or spits blood, should notify his doctor promptly. People who have repeated bouts of pneumonia, or a case of pneumonia that does not respond to treatment, should be checked to rule out the possibility of underlying malignant disease. It may also be suspected in any case of unresponding lung disease for which no cause of apparent. Early recognition and surgery to eradicate the disease are vital. Delay that permits, the cancer to spread beyond the confines of the lung is fatal.