The impact of lung cancer in our society cannot be denied. According to www.mydr.com.au "Lung cancer is the leading cause of cancer death in Australia and most other Western industrialized countries. One in 28 Australians will develop lung cancer by the age of 75, and about 6,700 Australians die from lung cancer each year". Lung cancer is one of the more difficult cancers to detect at its early stages and is one of the more difficult cancers to cure. However understanding the different neoplasms arising in the lung, as well as their staging and grading with regard to prognosis, has lead to some promising new treatment modalities.
Neoplasms of the lung
"Neoplasia literally means 'new growth'. It is a process which causes uncontrolled abnormal growth of tissue. Such tissue serves no useful function and does not coordinate with other body tissues. The mass of tissue formed by neoplasia is a neoplasm" van de Mortel (1998:29).
Lung cancer is a primary malignant neoplasm occurring in the bronchus, trachea or lung tissue. Most originate in the lining of the bronchi and are caused by exposure to environmental carcinogens, predominantly tobacco smoke.
At least 12 different cell types of tumors are included under the broad heading of lung cancer. For clinical and therapeutic reasons however, lung cancers are frequently classified as small cell cancers and non small cancers. McCance & Huether (2002:1136-1139), outline these neoplasms as follows.
Non-Small Cell Lung Cancer
NSCLC account for 75 per-cent of all lung cancers, they affect the cells that line the main bronchi. Some of the different types of non-small cancer include squamous cell carcinoma, adenocarcinoma and large cell carcinoma.
Squamous cell carcinoma
Squamous cell carcinoma accounts for about 30 per-cent of bronchogenic carcinomas. Almost always associated with smoking, their growth rate is slow and metastasis...