Types & Stages
There are two main types of lung cancer: non-small cell (accounting for 80 percent of all lung cancers) and small cell (accounting for the remaining 20 percent).
Non-small cell lung cancer is classified into three main categories:
- Adenocarcinomas, which arise from the mucus glands
- Squamous cell, or epidermoid, carcinomas, which are usually located in the bronchial tubes
- Large cell carcinomas, which are more commonly found near the lung surface
Small cell lung cancer, for the most part, grows and spreads quickly. There are two stages of the disease: limited and extensive.
Mesothelioma is another less common type of chest cancer. This cancer effects the lining of the lungs, called the pleura, and is often linked to asbestos exposure.
Stages of Lung Cancer
Staging is the process of finding out how far the cancer has spread. This is very important because your treatment and the outlook for your recovery depend on the stage of your cancer.
Accurate staging is probably the most important part of lung cancer treatment, because it allows the most appropriate therapy to be chosen and can help avoid ineffective or incorrect therapy. It is important to verify any X-ray findings that suggest more advanced cancer, as these X-rays can sometimes be wrong.
Determining the Stage
At Seattle Cancer Care Alliance (SCCA), the lung cancer team has a methodical and scientific approach to lung cancer staging that gives the benefit of the doubt to the patient rather than the cancer when there is any uncertainty in staging. This allows many patients to have a more aggressive therapy with a goal of cure, even when this may not have seemed possible based on initial X-ray evaluations.
Several methods may be used to determine the stage of the disease, including the following:
- Computed tomography (CT) scan—an X-ray machine linked to a computer which creates a series of detailed pictures of areas inside the body
- Magnetic resonance imaging (MRI) scan—a magnet connected to a computer which uses radio frequency waves to make detailed pictures of areas inside the body
- Positron emission tomography (PET) scan—a method of imaging the body’s physiologic functions by scanning for a radioactive substance that may collect in cancer cells
- Mediastinoscopy—a lighted scope inserted through an incision in the neck to access chest lymph nodes that may contain cancer
Your doctor may also want to do a brain scan or biopsies of lymph nodes or suspicious ares seen on X-rays.
Non-small Cell Lung Cancer Stages
Here’s how non-small cell lung cancer is staged.
- Stage I and II: Non-small cell lung cancer (NSCLC) is stage I or II if a surgeon can completely remove it. Stage I cancer has not spread to the lymph nodes. Stage II cancer may involve lymph nodes found within the lung, and it can be removed with the section of cancer in the lung.
- Stage III: Stage III NSCLC is difficult to remove and may not be removable at all. Stage IIIA is used when cancer has spread to the center of the chest or to the lymph nodes on the same side as the lung cancer. Stage IIIB is used when the cancer has spread to the lymph nodes on the opposite side of the chest.
- Stage IV: Stage IV NSCLC has spread to different lobes of the lung or elsewhere in the body.
Small Cell Lung Cancer Stages
Almost all small cell lung cancers spread outside the lung before they are discovered. Surgery is usually not possible, so patients receive chemotherapy treatment. Some may receive radiation therapy. Staging this disease helps doctors determine the best course of treatment.
- Limited-stage small cell lung cancer is located on one side of the chest and involves one region of the lung and lymph nodes. One-third of small cell lung cancer patients have limited stage.
- Extensive-stage small cell lung cancer has spread outside the lungs and possibly of the chest. Most patients are treated with chemotherapy only.
Advanced Lung Cancer
Despite treatment, lung cancer may come back. If cancer reappears in the lung, it is a local recurrence. Lung cancer cells can also travel through the lymph system or through the blood to reach other parts of the body, such as the bones. This is metastatic lung cancer.
Although tumors appear in distant sites—such as the lymph nodes, liver, bones or brain—these are not new cancers; this is a recurrence of the original lung cancer. In some cases, your lung cancer may have already metastasized, or spread, by the time you discover that you have lung cancer.
Metastatic lung cancer is generally seen as an incurable disease, but new treatments may put your cancer in remission and give you a good quality of life for a prolonged period of time.
If you have recurrent or metastatic lung cancer, SCCA can offer you new medical procedures and treatments, as well as access to clinical studies, that your community doctor may not know about. No one at SCCA will tell you that a diagnosis of metastatic lung cancer is not serious, but there is hope.
There are a number of new treatments that can be used against recurrent or advanced lung cancer, and one of these treatments may keep your disease under control. They include chemotherapy, radiation or a combination of both. Surgery is rarely used to treat metastatic lung cancer.
Your treatment will depend on a number of factors, including the type of treatment you have received in the past and the symptoms you are experiencing now. Your doctors may offer you radiation therapy or chemotherapy to relieve pain and other symptoms and to improve your quality of life.