The process of staging categorizes each cancer into certain standardized groups, which helps determine treatment options. Staging defines the extent that the cancer has spread from its original location in the lung to other parts of the body. Staging helps determine the prognosis of the disease as well as the course of treatment commonly recommended.

Staging is done either surgically and/or using scanning tests after the doctor has confirmed a diagnosis of lung cancer through a variety of methods. [Please refer to the section Risk Factors, Symptoms, Screening & Diagnostic Methods.]

Depending on the results of the tests described above, a chest surgeon—in consultation with the pathologist, the radiation oncologist, and the medical oncologist—can establish the stage of the lung cancer. This staging determines whether or not the cancer can be surgically removed. Lung cancer can be viewed as operable if cancer is not detected in any other organs, and the location of the tumor is such that surgery can be performed. If the tumor can be completely removed surgically, it is then defined as “resectable.” If there is a question, then surgery to make a further determination is often recommended.

During surgery, the lungs and the lymph nodes in the chest cavity are examined. This is called surgical staging. If the tumors can be removed, this is done at the same time the cancer is being staged. Ideally, a person who has been diagnosed with lung cancer should have his or her case discussed at a multidisciplinary conference of oncology specialists to ensure that the most appropriate therapy is recommended.

Because non-small cell lung cancer and small cell lung cancer are usually staged in somewhat different ways, their staging systems are described separately below.

Staging for NSCLC

Most physicians use the TNM classification system to stage non-small cell lung cancer (NSCLC). “T” refers to the size of the tumor, “N” refers to lymph node involvement, and “M” refers to metastasis. Basically, staging is based on the size and location of the primary tumor, the size and location of tumors other than those in the lungs, the presence of cancer cells in lymph nodes, and the spread of the cancer to other organs. All of this information is put together to determine the stage of tumor.

Your physician should tell you exactly what TNM stage of NSCLC you have before discussing treatment options with you.

Stages of Non-Small Cell Lung Cancer

Occult cancer means that cancerous cells are discovered in the sputum, but that no cancer can be found in the lung.

Stage 0 (also known as carcinoma in situ) is lung cancer that is found only in the layer of cells lining the air passages. Unfortunately, very few people are diagnosed at stage 0. Stage 0 lung cancer is usually discovered by a technique called “sputum cytology.” Most people who are diagnosed with stage 0 are participating in a screening trial or they sought out a special screening test like a spiral CT scan because they were concerned they were at risk.

 Stage IA means that the tumor is no larger than 3 centimeters (slightly less than 1¼ inches), has not spread to the membranes that surround the lungs, and does not affect the main branches of  the bronchi. In addition, the cancer has not spread to the lymph nodes or any other distant organ.  The most commonly recommended treatment at this stage is surgical removal of the tumor.

 Stage IB is defined by a tumor that has not spread to the lymph nodes or distant site and has one or more of the following features:

•  Is larger than 3 centimeters
•  Involves a main bronchus, but is not closer than 2 centimeters to where the trachea (windpipe) branches into the left and right main bronchi
•  Has spread to the membranes that surround the lungs
•  May partially clog the airways, but not enough to collapse the lung or develop pneumonia

Stage IIA means that the tumor is no larger than 3 centimeters, has not spread to the membranes that surround the lungs, and does not affect the main branches of the bronchi. However, the tumor has spread to the lymph nodes within the cancerous lung but not to any distant sites. Stage II lung cancer is treated with surgery, sometimes followed by radiation. Chemotherapy has not been proven to be effective with this stage at this time.

 Stage IIB lung cancer is diagnosed when the cancer has one or more of the following features:

• Is larger than 3 centimeters
• Involves the main bronchus, but not close to the windpipe
• Has spread to the membranes that surround the lung
• Has spread to the lymph nodes within the same cancerous lung

  Or,

• Has spread to the chest wall, the diaphragm, the membranes that surround the space between the lungs, or the membranes that surround the sac of the heart
• Involves the main bronchus and is closer to the windpipe where it branches into the right and left bronchi
• Has grown into the airways enough to cause one lung to collapse or develop pneumonia
• Has not spread to lymph nodes or distant organs

Stage III lung cancer means the cancer has spread to the lymph nodes in the middle of the chest away from the lungs. Treatment for stage III cancer involves a combination of chemotherapy and radiation and sometimes surgery. There are 2 types of stage III lung cancer:

Stage IIIA means the cancer is confined to the lung itself and the lymph nodes around the windpipe or in the mediastinum (place behind the chest bone and in front of the heart) on the  same side as the cancerous lung.

Stage IIIB involves a tumor of any size, that may involve the bronchus, trachea, esophagus, backbone, or the fluid in the space surrounding the lung and, most importantly, has spread to the lymph nodes near the collarbone on either side, and/or the lymph nodes within the lung, or mediastinal lymph nodes on the side that is opposite the cancerous lung. Therefore, your pretreatment work-up will focus on whether or not complete surgical removal of the tumor is possible or whether the cancer has already spread to the brain or bone. Whenever possible, your surgeon will try to remove the tumor(s). Sometimes chemotherapy or radiation is given first so that complete removal is more likely. If not, then you will most likely have radiation therapy with or without chemotherapy.

Stage IV is the most advanced form of lung cancer because the cancer has spread to distant parts of the body such as the liver, brain, or bone. At this stage, chemotherapy, usually a combination of different drugs, is the most commonly recommended form of treatment.

Stages of Small Cell Lung Cancer

The staging for small cell lung cancer is not put into the TNM staging criteria because the TNM criteria is a surgical staging system and surgery is rarely used in small cell lung cancer. Two stages are used to describe SCLC:

Limited-Stage SCLC means the cancer is in one lung and in the lymph nodes on the same side of the chest. In the following situations, it may be treated with a combination of chemotherapy and radiotherapy:

• The half of the chest in which the tumor originates
• The middle of the chest between the lungs (mediastinum)
• The lymph nodes closely adjacent to the lungs

Extensive-Stage SCLC describes any tumor or tumors that have spread to the other lung, to lymph nodes on the other side of the chest, or to areas too widely spread to fit the description of limited-stage disease such as the liver, brain, bone, adrenal glands, etc. This stage is usually treated with chemotherapy, (usually a combination of different drugs).

It is very important that you have a clear understanding about the type and stage of your lung cancer in order to evaluate your doctor’s recommendations for treatment. Talk with your physician, obtain copies of your original pathology report, and develop a solid understanding of your particular tumor type so that you can better partner with your physician as you chart your treatment course.