Staging the cancer is important because it will help your doctor determine what therapies will work best for your situation. The two main types of lung cancer, non-small-cell lung cancer (NSCLC) and small-cell lung cancer, are staged differently.
How Doctors Determine Lung Cancer Stage
Doctors often use imaging scans to stage a lung cancer. These tests might include magnetic resonance imaging (MRI), computerized tomography (CT) scan, or positron emission tomography (PET). A biopsy is also commonly performed to help doctors determine the stage of a cancer. Additionally, if you’ve had surgery for the cancer, your doctor can examine your tumor under a microscope to help stage it.
Clinical and Pathological Staging
There are two ways to stage lung cancer: clinical and pathological staging. Clinical staging is based on the results of your physical exams and imaging tests. The pathological stage can be determined if you’ve had surgery. In some situations, the clinical and pathological stages may be different. For instance, a cancer spot might not show up on an imaging scan, but your doctor might find it during surgery. In this case, your pathologic stage might be more advanced than your clinical stage. Because not everyone with lung cancer has surgery, clinical staging is more commonly used.
“T” stands for “tumor.” It describes your tumor’s size and where it’s located.“N” stands for “node.” It reveals if the cancer has spread to your lymph nodes.“M” stands for “metastasis.” It’s used to tell doctors if the cancer has spread to other parts of your body, such as the liver, bones, or brain.
These letters are often used along with the numbers (0, 1, 2, 3, and 4) to stage your tumor. The most common way to stage lung cancer is using a letter followed by a number.
Non-Small-Cell Lung Cancer Stages
The numerical system for staging lung cancers includes: Occult Stage This stage is often referred to as stage “X” or a “hidden cancer.” It means your tumor can’t be seen on imaging scans or a biopsy, but cancer cells show up in your mucus. Stage 0 A stage 0 lung cancer is very small and hasn’t spread into deeper lung tissues or outside the lungs. It’s sometimes known as “carcinoma in situ.” Stage 1 Stage 1 lung cancer means you have cancer in your lung tissues, but it hasn’t spread to your lymph nodes. The tumor is usually smaller than 2 inches across. Stage 2 Stage 2 lung cancers have spread to nearby lymph nodes. Stage 3 Stage 3 tumors have grown large and spread further into your lymph nodes and chest. Stage 4 Stage 4 lung cancer has spread outside the lung and lymph nodes, occasionally causing pleural effusions — a collection of fluid around the lung — or to more distant sites in your body, such as the liver, bones, and brain. Typically, the lower the number, the better your prognosis.
Substages A and B
Sometimes, stages of lung cancer are further subdivided into categories “A”, “B,” or “C”. For example, your doctor might say you have a lung cancer that’s “stage 2A” or “stage 2B.” The letters offer a more specific way to classify the cancer. Stage A is usually used to describe a cancer that’s slightly less aggressive within a certain category. Stage B typically refers to cancer that’s more aggressive.
Small-Cell Lung Cancer Stages
There are two stages for small-cell lung cancer: Limited The cancer is found on one side of the chest only and may include nearby lymph nodes. Extensive The cancer has spread to both lungs or to organs outside the chest.
Understanding Lung Cancer Stages
The lung cancer staging process is complex and may be difficult to understand. There are many letters and numbers involved, and it can get confusing. Some medical professionals even have trouble figuring it out. Talk to your doctor if you have any questions.
Lung Cancer Stages and Survival Rates
Often, survival rates are calculated based on the stage of the cancer. The National Cancer Institute’s most recent statistics show:
For people with stage 1A non-small-cell lung cancer (NSCLC), the five-year survival rate is about 49 percent. For stage 1B NSCLC, the five-year survival rate is about 45 percent.For those with stage 2A lung cancer, the five-year survival rate is about 30 percent. It’s about 31 percent for stage 2B.The five-year survival rate for stage 3A NSCLC is about 14 percent. For stage 3B cancers, it’s about 5 percent.For metastatic, or stage 4 NSCLC, the five-year survival rate is about 1 percent.
It’s important to remember that survival rates are only estimates. They can’t be used to predict what will happen to you specifically. They are also based on data from over a decade ago, and there have been many new therapies approved to treat lung cancer in the last decade that will likely improve these numbers.
