Staging of Non-Small Cell Lung Cancer

After non-small cell lung cancer is diagnosed, it is given a stage. The stage describes how large the tumor is, and how far it has spread in the body. Knowing the stage of lung cancer guides the health care team in choosing the most appropriate therapy. The stage of lung cancer at the time of diagnosis is also predictive of long-term survival.

Basic Staging of Non-Small Cell Lung Cancer

• Stage 0 – The cancer has not spread past the inner lining of the lungs; also known as carcinoma in situ

• Stage 1 – The cancer is localized within the lung and has not spread to any lymph nodes. Stage 1 is divided into stage 1A (tumors 3 cm or less in size), and stage 1B (tumors greater than 3 cm).

• Stage 2 – The cancer has spread to nearby lymph nodes, or has not spread to lymph nodes but is large, in a certain region of the main bronchus, or in a location where it invades the lung lining. Stage 2 is divided into stage 2A (a tumor 3 cm or less in size with spread to lymph nodes), or stage 2B (tumors 3 cm or greater in size with spread to lymph nodes, or present in locations such as a region of the main bronchus or invading the lung lining or chest wall).

• Stage 3 – The cancer has spread to tissue near the lungs. Stage 3 is divided in stage 3A (large tumors with spread to nearby lymph nodes, or any size tumor that has spread to lymph nodes further away from the tumor), and stage 3B (any size tumor that has spread to distant lymph nodes, a tumor that has invaded other structures in the chest such as the heart or esophagus, or a tumor with a malignant pleural effusion).

• Stage 4 – The cancer has spread to another part of the body. This can include spread to another lobe of the lung.

The TNM Staging System

Physicians often describe non small-cell lung cancer by something called the TNM system, which can be quite confusing at first. These letters stand for:

• T – indicates the size of the tumor
• N – describes if lymph nodes are involved
• M – defines whether metastasis (distant spread) has occurred

Oncologists use this system to further classify a cancer within the basic stages.

_Sources:

National Cancer Institute. Non-Small Cell Lung Cancer Treatment. Updated 03/08/08.