Gastric Cancer

Treatment

The primary treatments for gastric cancer include surgery, radiation and chemotherapy. Patients with early cancers (cancer confined to the wall of the stomach that has not entered the lymph nodes) can usually be treated with surgery alone, but cancers that have spread beyond the wall of the stomach or involve lymph nodes require the addition of external beam radiation and chemotherapy. Cancers that have spread through the bloodstream or abdominal cavity may be treated primarily with chemotherapy.

The advantage of adding radiation and chemotherapy to surgery was demonstrated in a large randomized trial performed in the United States that compared treatment with surgery alone versus surgery followed by radiation and chemotherapy. Patients in the trial had tumors extending beyond the stomach wall, tumors that involved lymph nodes or both. Mayo Clinic physicians were involved in both the design and treatment phase of this important trial.

For patients who may need all three treatment options, the sequencing of surgery with radiation and chemotherapy depends on the location and extent of the cancer. If the cancer does not involve the esophagus, surgery is used first, followed by radiation and chemotherapy if necessary. If the cancer is in the esophagus as well as the stomach, then radiation and chemotherapy are usually used first and surgery is done later if needed. For patients with localized, advanced cancers that have extended beyond the wall of the stomach to nearby organs, external beam radiation plus chemotherapy are usually given before surgery. Intraoperative radiation (IORT) with electrons may be given at the time of surgery. Gastric lymphomas are generally treated without surgery.

Mayo Clinic physicians work carefully to develop an individualized, comprehensive treatment plan. This treatment plan depends on a person's general health and the stage (extent) of the cancer. People with advanced disease (tumor spread to other sites) can often participate in clinical trials that offer experimental therapies.

Surgery

A surgeon will remove the part of the stomach that contains the cancer along with a small amount of noncancerous tissue. Most gastric operations are for adenocarcinoma and are usually a partial or total gastrectomy. Lymph nodes in the region are usually taken out as well. In rare cases, the surgeon will remove the stomach and connect the esophagus directly to the small intestine.

For some people with very early disease, endoscopic techniques can be used in place of traditional surgery. An endoscopist (physician specializing in endoscopic procedures) directs an endoscope (a flexible tube) into the stomach through the mouth. This allows the endoscopist to view the stomach and destroy the tumor through endoscopic mucosal resection or laser therapy. In cases of inoperable gastric tumors, an endoscope can be used to place a stent (tube) that allows food and liquid to pass through the stomach. Specialists consider this to be palliative treatment (care that provides comfort but does not cure the cancer). Palliative gastrectomy may be appropriate in patients who have a tumor obstruction not amenable to stenting or have significant tumor hemorrhage or a perforated cancer.

During surgery, surgeons can determine whether the cancer has penetrated the wall of the stomach or spread to other parts of the body. This knowledge helps them decide whether chemotherapy and radiation are appropriate.

Chemotherapy

Chemotherapy involves the use of drugs to destroy cancer cells. Chemotherapy may be given after surgery, given during and following radiation, or given to treat cancer that may remain after surgery. Chemotherapy usually begins about a month after surgery and continues for six months. Medical oncologists may recommend chemotherapy as the main treatment option when the tumor cannot be surgically removed because of spread within the abdominal cavity or through the bloodstream to other organs such as the liver or lungs.

Radiation Therapy

Radiation is given to destroy cancer cells while minimizing the radiation dose to surrounding healthy tissue. Physicians may recommend radiation, including intraoperative radiation (IORT), in combination with chemotherapy or surgery.

When external beam radiation (EBRT) is necessary, it is usually delivered with sophisticated radiation techniques involving either 3-D conformal radiation therapy or intensity-modulated radiation therapy (IMRT). These specialized techniques are used to limit the radiation dose to nearby organs and structures such as the liver, lungs, kidneys, spinal cord and small intestine. A typical course of treatment with EBRT and concurrent chemotherapy consists of a series of 25-30 radiation treatments delivered five days per week (Monday through Friday) during five to six weeks.

It may be advantageous for patients to receive this specialized treatment in centers where radiation oncologists specialize in the treatment of gastric and other gastrointestinal cancers such as Mayo Clinic. Radiation oncologists at Mayo have extensive experience in the treatment of patients with gastric cancer and cancers at the junction of the esophagus and stomach.

Biological Therapy

Biological therapy, also called immunotherapy, uses the body's immune system to fight cancer. The immune system finds cancer cells in the body and works to destroy them. Biological therapies may be used to repair, stimulate or enhance the immune system's natural anticancer function. They may be combined with other treatments.