Chemotherapy uses drugs to kill cancer cells. Chemotherapy is a systemic treatment because the drugs travel through the entire body in the bloodstream, killing all cells that rapidly divide. That means the drugs can kill cancer cells as well as some healthy cells. This type of treatment doesn't usually cure stomach cancer.
Chemotherapy is not commonly used for early-stage stomach cancer when the cancer has not spread outside the stomach.
Chemotherapy is most often used when cancer is advanced and has spread to distant organs. It can help lengthen your life span, but it is not considered a cure.
Your doctor may recommend chemotherapy for these reasons:
You need treatment after surgery to help keep the cancer from coming back, which is called recurrence. Chemotherapy used in this setting is called adjuvant therapy. Your doctor may combine chemotherapy with radiation after surgery. When used with radiation, a drug called 5-fluorouracil may be used. Fluorouracil may increase the effect of the radiation on the cancer. This is called radiosensitization.
You need treatment to shrink a tumor. This might be done before surgery, to make the tumor easier to remove and to lower the chance of recurrence. Having another treatment before surgery is called neoadjuvant therapy.
You have stomach cancer that has spread to distant parts of the body. Chemotherapy may help shrink or slow the growth of the cancer or may be used to ease symptoms caused by the cancer, such as pain.