Consultancy Corner: Lung cancer - Prevention, early detection and treatments

Smoking tobacco is the largest reason for developing lung cancer and accounts to about 85 per cent of the cause of the disease. The risk increases depending upon number of cigarettes smoked daily and the duration of smoking. Those who breathe in second-hand smoke are not spared either. This is especially true for women who are exposed to passive smoking and whose risks go up by 30 per cent. Other factors of lung cancer include exposure to chemicals like coal gas, Radon, Asbestos, pesticides etc., besides family history.

Air pollution is an increasingly important risk factor for lung cancer among former and never-smokers and as pollution levels continue to climb in urban centers of many low- and middle- income countries, there is a significant global shift in the causes of lung cancer. Air pollution is a complex mix of gases and aerosols (suspended solid and liquid particles), the most measured and important pollutant of concern is particle pollution, also called particulate matter (PM), which manifests as dust, soot, smog, or smoke. Fine particulate matter, also known as PM2.5, or particles less than 2.5 microns across, has the largest impact on public health globally. Vehicle exhaust, industrial emissions, solid fuel use, and refuse burning are some of the most common sources of PM2.5 air pollution in urban centers across the world and this is a recognized marker for the risk of development of lung cancer. There is an urgent need to not only raise awareness of air pollution as a cause of lung cancer, but to explore how public health control strategies for tobacco could be applied to control air pollution.  

Broadly Lung cancer is divided into two types: Small cell and Non-small cell. The Non-small type is further sub classified several types based on histological appearance like Squamous, Adeno, Large cell etc.

Screening for lung cancer is recommended for high-risk patients like heavy smokers (more than 30 years) and industrial workers with exposure to chemicals. A chest X-ray can easily miss early lesions hence a CT Scan of the chest is recommended for lung cancer screening followed by a biopsy of any suspicious lesions.

Depends on the type of lung cancer and extent the disease has spread to (metastasis). Small cell lung cancer is mostly treated with chemotherapy or a combination of chemotherapy and radiation therapy. Non-small cell cancer can be treated with curative surgery if it is localized and detected early, or a combination of surgery, chemotherapy and radiation. Targeted therapy which aims at certain mutations in the cancer cells like EGFR, ALK etc has revolutionized chemotherapy with less side effects and better efficacy than conventional chemotherapy.

This has been a milestone in treatment of advanced lung cancer  which is designed to boost body’s natural defenses  and blocking pathways by which cancer cells evade body’s immune system with specific Antibodies. This has resulted in prolonged survival and improved quality of life in these patients.