Chemotherapy is the use of medications to treat the cancer. It is given either intravenously (through a vein) or in a pill form which is swallowed. While surgery and radiation are “local” treatments (they treat the cancer only at the spot which treatment is aimed), chemotherapy treats the cancer “systemically” (it travels through the bloodstream to all areas of the body). Because chemotherapy is “systemic” it is mostly used to treat cancer which has spread through the bloodstream as well (stage 3 and 4).

Adjuvant chemotherapy involves giving drugs after surgery was performed with the intent of curing the patient.  Even small cancers may have spread before being removed despite normal scans such as PET.  Research has shown that chemotherapy improves the cure rates for certain high-risk patients after successful operations.

In some instances, chemotherapy is given in combination with radiation therapy. This is because research has shown that the combination of the two offers a higher chance of cure for advanced lung cancer (stage 3).

Currently studies are being done to determine if chemotherapy and radiation followed by removing the tumor surgically offers greater chance for cure and absence of recurrence. Treatment given in this way is called “neoadjuvant therapy.”