Lung cancer: staging, imaging and surgery

Primary cancer of the lung is the leading cause of cancer-related deaths in industrialized countries. The overall 5-year survival for this disease is only 5.5% in the UK. Smoking is the primary risk factor for lung cancer and is responsible for 85% of all cases in the UK. The most important distinction is between non-small-cell cancer (NSCLC) and small-cell lung cancer (SCLC). SCLC is a clinically aggressive tumour and most patients present with systemic disease; it is rarely amenable to curative surgery. The aims of evaluating a patient suspected of having lung cancer are to establish the cell type of the tumour, determine the stage of disease, and to determine the functional status of the patient to assess his suitability for surgery. Precise clinical staging is of particular importance because it determines prognosis and guides therapy. A precise classification has been developed for NSCLC based on the TNM classification system. A number of invasive and non-invasive procedures are used to diagnose and stage lung cancer. Surgery is the only established method for curing NSCLC, but only one-quarter of patients have resectable disease at presentation. Lung resection is the best form of treatment for stage I and stage II disease. The aims of surgery are to achieve a complete resection of the tumour and its intrapulmonary lymphatics. This is best achieved with an anatomic resection-usually a lobectomy or pneumonectomy. The mortality after lobectomy is 2-4%, whilst the mortality of pneumonectomy is 6-8%.