Lung Cancer 101
Lung cancer is a well-known but often misunderstood disease. When treated early, many patients continue to do well. In 2007 there are 330,000 long term cancer survivors.
Lung cancer is the most frequently diagnosed cancer in the US. Each year 170,000 Americans are diagnosed with lung cancer. From 1930 to 1997 the rate of lung cancer has risen 600% in women, a sign of equality no one wanted to see. While cigarette smoke is considered the leading cause of lung cancer, 20-25% of women with lung cancer are non-smokers. Environmental factors such as exposure cancer-causing agents such as asbestos or radon have been known to cause lung cancer or when combined with cigarette smoke to increase chance of developing lung cancer.
There are two main types of lung cancer—small cell lung cancer and non-small cell lung cancer. Squamous cell, large cell and adenocarcinoma are three common forms of non-small cell lung cancer. About 85% of all lung cancers are caused by non-small cell cell cancers. Small cell lung cancers (also known as oat cell cancer) account for about 15% of lung cancers diagnosed in the US. Small cell lung cancers tend to grow and spread more quickly than non-small cell.
Lung cancer is not inherited like eye color or height, but underlying genetic factors influence susceptibility if smoking or other environmental factors are there to trigger problems. The leading cause of lung cancer is cigarette smoking. More than 80% of lung cancers are caused by tobacco, including cigarettes, pipes and cigars. Tobacco affects not only the users. This smoke is potentially deadly for people who live and work with smokers. In fact 20-25% of lung cancer in women is found in non-smokers and many of these cases are felt to be due to second hand smoke.
Other chemicals either singly or in combination with tobacco smoke have been linked to lung cancer. Asbestos used as insulation in brake linings and construction, silica dust found in mines and radiation have been found to increase risk of lung cancer.
Lung cancer may not cause symptoms in its earliest stages. As the cancer cells develop in the airways, symptoms such as chronic cough, blood tinged phlegm, shortness of breath, chest pain and repeated episodes of bronchitis may occur. As a pulmonologists, I will see patients who are concerned about the arrival of one or more of classic symptoms. In other cases, a suspicious nodule is picked up on an X-ray during a routine physical.
Diagnosis usually starts with the evaluation of a chest x-ray to characterize the size and location of a suspicious shadow. To further refine our information, we usually order a CT scan. This piece of equipment provides a more accurate image and can give us better information on the size and location of the nodule. We usually want to biopsy the nodule in order to confirm the diagnosis and determine what kind of cancer we are dealing with. For this we use a procedure called bronchoscopy or fine needle biopsy. We may also do a PET scan to learn if the cancer has spread.
Like asthma and COPD, lung cancer is described in terms of stages. Lung cancer is defined in stages I-IV. Determination of the stage depends on the size, number and location of the nodules as well as spread to the lymph nodes and other parts of the body.
Treatment depends on balancing the type of cancer, the stage at which it was diagnosed and the health of the person with lung cancer. There are three main types of treatment—surgery, radiation and chemotherapy. Within these three groups there are a wide range of options that are often combined to develop a personalized treatment plan for the best results.
Lung cancer is a serious diagnosis and it is essential that you have support from you family and health care team, as well as early expert opinion. When dealing with lung cancer (as well as any serious illness), it is always wise to get a second opinion. Donít be concerned about hurting your doctorís feelings. Good doctors know that a second opinion is good medicine.