Non-small cell lung cancer (NSCLC) is the most common type of lung cancer. Adjuvant therapy is additional treatment given after surgery to reduce the risk that the cancer will come back. Adjuvant treatment may include chemotherapy (the use of drugs to kill cancer cells) and/or radiation therapy (the use of high energy x-rays to kill cancer cells). This guide for patients explains whether chemotherapy and radiation therapy are recommended treatments after surgery to remove the lung cancer, depending on the stage of the cancer.

Staging is a way of describing the cancer, such as its size, and if or where the cancer has spread. Cancer may spread through the blood or lymphatic system. The lymphatic system is part of the immune system and drains fluid from body tissues through a series of tubes. Lymphatic fluid is filtered in small, bean-shaped organs called lymph nodes. When cancer cells travel in the lymphatic system, they become trapped in the lymph nodes.

The treatment for stage I, II, and IIIA NSCLC includes surgery to remove the tumor and the surrounding lung tissue and lymph nodes. The stage of NSCLC is described by a number, one through four (Roman numerals I-IV). A higher stage of cancer means that the risk that the cancer may come back is also higher.

• Stage I NSCLC means that the cancer has not spread to nearby lymph nodes. Stage IA means the primary tumor is relatively small. Stage IB means the primary tumor is relatively large, or is located in a place where it is more likely to spread.

A stage I cancer can usually be removed by surgery.

• Stage II NSCLC describes a cancer that may have spread to nearby lymph nodes. Stage IIA means the primary tumor is relatively small. Stage IIB means the primary tumor is relatively large, or is located in a place where it is more likely to spread. In a stage II cancer, both the tumor and the affected lymph nodes can usually be removed by surgery.
• Stage III NSCLC may be difficult to remove with surgery. When the cancer has spread to lymph nodes in the center of the chest, on the same side as where the cancer started, it is known as stage IIIA. When the cancer spreads to lymph nodes on the opposite side of the chest, it is known as stage IIIB. In general, surgery is not used for any stage IIIB lung cancer.
• Stage IV NSCLC has spread through the bloodstream to areas of the body outside of the lung and is not treated with surgery.

This patient guide applies to stage I, II, and IIIA NSCLC.