Lung Cancer - Small Cell: Stages

Approved by the Cancer.Net Editorial Board, 03/2018

ON THIS PAGE: You will learn about how doctors describe a cancer’s growth or spread. This is called the stage. Use the menu to see other pages.

Staging is a way of describing where the cancer is located, if or where it has spread, and whether it is affecting other parts of the body. Doctors use diagnostic tests to find out the cancer’s stage, so staging may not be complete until all of the tests are finished. Knowing the stage helps the doctor to decide what kind of treatment is best and can help predict a patient’s prognosis, which is the chance of recovery. There are different stage descriptions for different types of cancer.

In general, a lower number stage of small cell lung cancer is linked with a better outcome. However, no doctor can predict how long a patient will live with small cell lung cancer based only on the stage of disease because it is different in each person, and treatment works differently for each tumor.

Cancer stage grouping

The most common way doctors stage small cell lung cancer is by classifying the disease as limited stage or extensive stage.

  • Limited stage. Limited stage means that the cancer is only in 1 part of the chest and radiation therapy could be a treatment option. About 1 out of 3 people with small cell lung cancer have limited stage disease when first diagnosed.

  • Extensive stage. Extensive stage is used to describe small cell lung cancer that has spread to parts of the body such as the other lung, bone, brain, or bone marrow. Many doctors consider small cell lung cancer that has spread to the fluid around the lung to be extensive stage as well. About 2 out of 3 people with small cell lung cancer have extensive disease when the cancer is first found.

Small cell lung cancer is often staged in this way because it helps doctors decide if a patient might benefit from more aggressive treatments. Learn more about treatment options for small cell lung cancer.

There is another, more formal system to describe the stage of lung cancer, but small cell lung cancer is almost always staged as limited or extensive stage as described above. The other, less commonly used staging system gives a number, 0 through 4, based on whether the tumor can be completely removed by a surgeon. Less than 5% of people have early-stage lung cancer (stage 0 to stage 2). About 25% of people have stage 3 (III) disease when first diagnosed. Stage 0 to stage 3 are called limited stage. Most patients with small cell lung cancer have extensive or stage 4 (IV) disease when first diagnosed.

Stage 0

This is called in situ disease, meaning the cancer is “in place” and has not grown into nearby tissues and spread outside the lung.

Stage I

A stage I lung cancer is a small tumor that has not spread to any lymph nodes, making it possible for a surgeon to completely remove it. Stage I is divided into 2 substages based on the size of the tumor:

  • Stage IA tumors are 3 centimeters (cm) or less in size. Stage IA tumors may be further divided into IA1, IA2, or IA3 based on the size of the tumor.

  • Stage IB tumors are more than 3 cm but 4 cm or less in size.

Stage II

Stage II lung cancer is divided into 2 substages:

  • A stage IIA cancer describes a tumor larger than 4 cm but 5 cm or less in size that has not spread to the nearby lymph nodes.

  • Stage IIB lung cancer describes a tumor that is 5 cm or less in size that has spread to the lymph nodes. Or a stage IIB cancer can be a tumor more than 5 cm wide that has not spread to the lymph nodes.

Stage III

Stage III lung cancers are classified as either stage IIIA, IIIB, or IIIC. The stage is based on the size of the tumor and which lymph nodes the cancer has spread to. Stage III cancers have not spread to other distant parts of the body.

Stage IV

Stage IV means the lung cancer has spread to more than 1 area in the other lung, the fluid surrounding the lung or the heart, or distant parts of the body through the bloodstream. Once cancer cells get into the blood, the cancer can spread anywhere in the body. Stage IV is divided into 2 substages:

  • Stage IVA cancer has spread within the chest and/or has spread to 1 area outside of the chest.

  • Stage IVB has spread outside of the chest to more than 1 place in 1 organ or to more than 1 organ.

Used with permission of the American College of Surgeons, Chicago, Illinois. The original and primary source for this information is the AJCC Cancer Staging Manual, Eighth Edition (2017) published by Springer International Publishing.

Prognosis

The stage of small cell lung cancer and the patient’s overall health influence prognosis. Although small cell lung cancer is treatable at any stage, only some people with certain stages of small cell lung cancer can be cured.

Doctors measure a patient’s general strength and health using an index known as performance status. Patients who are strong enough to go about their daily activities without assistance and work outside the home can safely receive chemotherapy, radiation therapy, and/or surgery. Treatment may not be as effective for patients with small cell lung cancer that has spread to the bones or liver, excessive weight loss, ongoing cigarette use, or pre-existing medical conditions, such as heart disease or emphysema.

It is important to note that a patient’s age has never been useful in predicting whether a patient will benefit from treatment. The average age of patients with small cell lung cancer in the United States is 71. A patient’s age should never be used as the only reason for deciding what treatment is best, especially for older patients who are otherwise physically fit and have no medical problems besides small cell lung cancer.

Information about the cancer’s stage will help the doctor recommend a specific treatment plan. The next section in this guide is Types of Treatment. Use the menu to choose a different section to read in this guide.