A. LUNG CANCER: Definition: According to the National Cancer Institute (2009), lung cancer refers to the uncontrolled and abnormal proliferation of lung tissue, usually in the cells lining the airways1. It occurs when there is an overgrowth of cells present in the lungs leading to a variety of clinical symptoms. Classification: The International Classification of Diseases, ICD-10, classifies lung cancer under C34 as a malignant neoplasm of the bronchi and lung2. When routine statistics are reported, tumors of the lung and bronchi are grouped together with those of the trachea C333. Pathology and clinical features: Lung cancer occurs mainly in adults between 45 and 75 years of age and approximately 80 - 90% of all cases smoke. smoking as the main etiological factor4-6. The chance of developing lung cancer is higher in those who start smoking at a young age and also in heavy smokers than in light smokers5. Other risk factors include exposure to radon gas, asbestos, uranium and pitchblende miners, chromium and nickel refiners, welders, and workers exposed to halogenated ethers. 5. There are basically two types of lung cancer, small cell tumor and non-small cell tumor that can be differentiated microscopically. The main clinical features of lung cancer include cough (80%), hemoptysis (70%), dyspnea (60%), and chest pain (40%). Others include recurrent or slowly resolving pneumonia, weight loss, anemia, anorexia, and swollen lymph nodes. 7. Epidemiology: Lung cancer is the second most common cancer diagnosed in the UK (excluding non-melanoma skin cancers) and is more common in men than women (Figure 1.0). Lung cancer accounted for approximately 39,000 (Figure 1.3) of all UK cancer cases diagnosed in... half of article......arch/articlesBySubject/displaystory.cfm?subjectid=349008&story_id=E1_TPSGGQRP. Accessed 11/28/2009.22. Why People Smoke Available at: http://healthliteracy.worlded.org/docs/tobacco/Unit3/1why_people_smoke.html. Accessed 11/29/2009.23. Walker MS, Vidrine DJ, Gritz ER, Larsen RJ, Yan Y, Govindan R, et al. Smoking relapse during the first year after treatment for early-stage non-small cell lung cancer. Cancer Epidemiol Biomarkers Prev 2006; December; 15(12):2370-7.24. Britain quits smoking - Times Online Available at: http://www.timesonline.co.uk/tol/news/uk/article730913.ece. Accessed 11/28/2009.25. Get help to stop smoking – NHS Stop Smoking Campaign – Quit Smoking Available at: http://www.canstopsmoking.com/. Accessed 11/29/2009,26. Smoking and Lung Cancer Associations Available at: http://www.medscape.com/viewarticle/576699. Logged in 11/28/2009