Every cancer, including lung cancer, starts out as single cell that changes from a normal cell into a cancerous cell. This usually occurs because one or more sections of the cell’s DNA have suffered mutation(s). When a tumor forms, it is made up of a collection of abnormal cells all descendants of that same cancerous cell. Therefore when a physician makes a diagnosis of cancer, it is important to determine which cell type is responsible for the tumor. The type of cell determines the course of treatment, the course of the disease, and the prognosis.
There are two main groups of lung cancer, small-cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). About 85% of all lung cancers are non-small cell lung cancers. Non-small cell lung cancers are divided into three main types: large cell carcinoma, squamous cell carcinoma, and adenocarcinoma of the lung. The remainder are small-cell lung cancers.
Non-small cell lung cancer (NSCLC) is the most common form of lung cancer. NSCLC gets its name from the way that the cancer cells look under a microscope. Since there are several different types of non-small cell lung cancer histologically, NSCLC is first distinguished from small-cell lung cancer and then further differentiated into subtypes.
In the overwhelming majority of cases, NSCLC arises from four major causes: active smoking, passive smoking (secondhand smoke), asbestos, and radon exposure. Certain other metals and toxins have a role in lung cancer as well; however, they are much less frequently the cause of lung cancer than smoking and the other top four.
Smoking is responsible for as many as 90% of all lung cancers. Tobacco smoke can lead to lung cancer in several ways. Most notably, cigarette smoke contains a number of carcinogens (cancer-causing molecules) that can directly interfere with the DNA of a cell. These toxins cause mutations in the DNA that lead to abnormal cell growth and development. The carcinogens in inhaled smoke also interfere with the cell’s ability to inhibit its own growth. Therefore the cell begins to multiply uncontrollably, which creates a tumor.
Of the 10% of lung cancers that are not caused by active smoking, as many as 25% of these tumors are caused by secondhand smoke. It has been shown that some carcinogens can be inhaled by people that are near active smokers. The negative effects of these toxic compounds on the lungs are similar to those who actively smoke.
Another major cause of lung cancer is asbestos exposure, specifically exposure to silicate asbestos. Asbestos has been linked to a variety of lethal and debilitating lung diseases. Asbestos exposure increases the risk of lung cancer 5-fold; for those exposed to smoke AND asbestos, the chance of developing lung cancer is 55 to 85 times the risk of someone who has not been exposed to these environmental factors.
Compensation information is available for those diagnosed with lung cancer. Call us toll-free at 1-800-258-1054.