lung cancer

Diagnosis, Prevention and Screening

Diagnosis

Performing a chest x-ray is the first step if a patient reports symptoms that may be suggestive of lung cancer. This may reveal an obvious mass, widening of the mediastinum (suggestive of spread to lymph nodes there), atelectasis (collapse), consolidation (pneumonia), or pleural effusion. If there are no x-ray findings but the suspicion is high (such as a heavy smoker with blood-stained sputum), bronchoscopy and/or a CT scan may provide the necessary information. Bronchoscopy or CT-guided biopsy is often used to identify the tumor type.^[4]

CT scan showing a cancerous tumor in the left lung.

The differential diagnosis for patients who present with abnormalities on chest x-ray includes lung cancer as well as nonmalignant diseases. These include infectious causes such as tuberculosis or pneumonia, or inflammatory conditions such as sarcoidosis. These diseases can result in mediastinal lymphadenopathy or lung nodules, and sometimes mimic lung cancers.^[5] Lung cancer can also be an incidental finding: a solitary pulmonary nodule (also called a coin lesion) on a chest x-ray or CT scan taken for an unrelated reason.

Prevention

Prevention is the most cost-effective means of fighting lung cancer. While in most countries industrial and domestic carcinogens have been identified and banned, tobacco smoking is still widespread. Eliminating tobacco smoking is a primary goal in the prevention of lung cancer, and smoking cessation is an important preventative tool in this process.^[62]

Policy interventions to decrease passive smoking in public areas such as restaurants and workplaces have become more common in many Western countries, with California taking a lead in banning smoking in public establishments in 1998. Ireland played a similar role in Europe in 2004, followed by Italy and Norway in 2005, Scotland as well as several others in 2006, England in 2007, and France in 2008. New Zealand has banned smoking in public places as of 2004. The state of Bhutan has had a complete smoking ban since 2005.^[63] In many countries, pressure groups are campaigning for similar bans. In 2007, Chandigarh became the first city in India to become smoke-free.

Arguments cited against such bans are criminalisation of smoking, increased risk of smuggling, and the risk that such a ban cannot be enforced.^[64]

A 2008 study performed in over 75,000 middle-aged and elderly people demonstrated that the long-term use of supplemental multivitamins—such as vitamin C, vitamin E, and folate—did not reduce the risk of lung cancer. To the contrary, the study indicates that the long-term intake of high doses of vitamin E supplements may even increase the risk of lung cancer.^[65]

The World Health Organization has called for governments to institute a total ban on tobacco advertising in order to prevent young people from taking up smoking. They assess that such bans have reduced tobacco consumption by 16% where already instituted.^[66]

Screening

Screening refers to the use of medical tests to detect disease in asymptomatic people. Possible screening tests for lung cancer include chest x-ray or computed tomography (CT) of the chest. So far, screening programs for lung cancer have not demonstrated any clear benefit. Randomized controlled trials are underway in this area to see if decreased long-term mortality can be directly observed from CT screening.^[67]

posted by nugrahaboy (Hafiz Hari Nugraha) @ 6:04 AM