| The great majority of lung cancers originate | | | | Symptoms. Symptoms vary with the size and |
| within the walls of the bronchi, the three-like | | | | location of the tumor. The patient develops a |
| structures of tubes which carry air to the lungs. | | | | cough early in the illness. It is usually dry but there |
| That is why lung cancers are more correctly | | | | may be blood in the mucus. There is chest pain |
| know as bronchogenic cancers. The direct cause | | | | similar to that of pleurisy. The patient is often |
| of this form of cancer, like all other cancers, is | | | | short of breath and wheezes as he breathes. His |
| unknown. However, there is much evidence to | | | | finger joints swell painfully. There can be swelling |
| show that cigarette smoking is responsible factor, | | | | of the face and upper extremities, and swallowing |
| as well as inhalation of certain irritating dusts | | | | difficulties, depending upon where the tumor |
| (including cobalt and chromates) and fumes. Lung | | | | located. |
| cancer cases have increased, and now account | | | | Complications. Complications include collapse of the |
| for about 15% of all cancers. The disease occurs | | | | lung, recurrent pneumonias, bronchiectasis, and |
| in middle life or later, with greater frequency in | | | | lung abscess. However, the real danger is the fatal |
| men. | | | | spread of this tumor to other parts of the body. |