Stage III Gastric Cancer


Patients with stage III gastric cancer have spread of cancer to structures adjacent to the stomach and/or to regional lymph nodes. Stage III gastric cancer can be further divided into stage IIIA and stage IIB.  Stage IIIA gastric cancer invades the muscle of the wall of the stomach and 7 or more lymph nodes, the next-to-the-last layer of the stomach and 3-6 lymph nodes, or the outermost layer of the stomach (the serosa) and 1-2 lymph nodes.  Stage IIIB gastric cancer invades the next-to-the-last layer of the stomach and 7 or more lymph nodes, the outermost layer of the stomach and 3-6 lymph nodes, or adjacent structures and few (1-2) or no lymph nodes.

A variety of factors ultimately influence a patient’s decision to receive treatment of cancer. The purpose of receiving cancer treatment may be to improve symptoms through local control of the cancer, increase a patient’s chance of cure, or prolong a patient’s survival. The potential benefits of receiving cancer treatment must be carefully balanced with the potential risks of receiving cancer treatment.

The following is a general overview of the treatment of Stage III gastric cancer. Circumstances unique to your situation and prognostic factors of your cancer may ultimately influence how these general treatment principles are applied. The information on this Web site is intended to help educate you about your treatment options and to facilitate a mutual or shared decision-making process with your treating cancer physician.

Most new treatments are developed in clinical trials. Clinical trials are studies that evaluate the effectiveness of new drugs or treatment strategies. The development of more effective cancer treatments requires that new and innovative therapies be evaluated with cancer patients. Participation in a clinical trial may offer access to better treatments and advance the existing knowledge about treatment of this cancer. Clinical trials are available for most stages of cancer. Patients who are interested in participating in a clinical trial should discuss the risks and benefits of clinical trials with their physician. To ensure that you are receiving the optimal treatment of your cancer, it is important to stay informed and follow the cancer news in order to learn about new treatments and the results of clinical trials.

Optimal treatment of patients with Stage III gastric cancer often requires more than one therapeutic approach. Thus, it is important for patients to be treated at a medical center that can offer multi-modality treatment involving medical oncologists, radiation oncologists, surgeons, medical gastroenterologists and nutritionists.

Surgery as Primary Treatment

Depending a patient’s circumstances, surgery may be performed with the goal of curing Stage III cancer or to relieve symptoms caused by the cancer. Surgery may involve removal of all or part of the stomach, and typically includes removal of several lymph nodes as well.

For Stage III gastric cancer patients who are candidates for surgery, surgery is often combined with other approaches to treatment such as chemotherapy. Some patients receive chemotherapy both before and after surgery. For patients who don’t receive chemotherapy prior to surgery, chemotherapy may be given in combination with radiation therapy after surgery.

In some cases, the patient may be too ill to undergo surgery or the cancer may be too extensive to allow surgery, and the patient will be offered non-surgical approaches to treatment.

Patients with Stage III gastric cancer should consider treatment at a medical center with a surgical team that has experience and treats a large number of patients with gastric cancer each year. To learn more about surgical treatment, go to Surgery for Gastric Cancer.

Neoadjuvant Therapy (Treatment Before Surgery)

Some patients may receive treatment with chemotherapy (with or without radiation therapy) prior to surgery. This treatment can help to reduce the extent of cancer, making it easier to remove the cancer during surgery.

Adjuvant Therapy (Treatment After Surgery)

The goal of additional treatment after surgery is to reduce the risk of cancer recurrence by eliminating any areas of cancer that may remain in the body. Adjuvant (post-surgery) therapy for Stage III gastric cancer typically involves chemotherapy alone or in combination with radiation therapy.

Chemotherapy and Radiation Therapy as Primary Treatment

If the cancer cannot be surgically removed or the patient is medically unable to undergo surgery, treatment of Stage III gastric cancer may involve a combination of chemotherapy and radiation therapy. It appears that the combination of chemotherapy and radiation therapy has substantial activity for the local control of advanced gastric cancer.

Strategies to Improve Treatment

The progress that has been made in the treatment of gastric cancer has resulted from the use of multi-modality treatment and improved patient and physician participation in clinical studies. Future progress in the treatment of gastric cancer will result from continued participation in appropriate studies. Currently, there are several areas of active exploration aimed at improving the treatment of gastric cancer.

Supportive Care: Supportive care refers to treatments designed to prevent and control the side effects of cancer and its treatment. Side effects not only cause patients discomfort, but also may prevent the optimal delivery of therapy at its planned dose and schedule. In order to achieve optimal outcomes from treatment and improve quality of life, it is imperative that side effects resulting from cancer and its treatment are appropriately managed. For more information, go to Managing Side Effects.

New Neoadjuvant or Adjuvant Regimens: Development of new multi-drug chemotherapy treatment regimens that incorporate new or additional anti-cancer therapies is an active area of clinical research carried out in clinical trials. Treatment before and/or after surgery may consist of chemotherapy alone or in combination with radiation therapy or targeted therapy. Targeted therapies interfere with specific biological pathways involved in cancer growth or survival. A type of targeted therapy that improves outcomes for selected patients with advanced gastric cancer is Herceptin® (trastuzumab). Herceptin targets a protein known as HER2 that can stimulate cancer growth. Roughly 20% of patients with gastric cancer have cancer that overexpresses (makes too much of) this protein; these cancers are referred to as HER2-positive. For patients with HER2-positive, metastatic gastric cancer, treatment with Herceptin can improve overall survival. Based on these results, studies are also evaluating the role of Herceptin and other targeted therapies for earlier-stage gastric cancer.

Multiple Drug Resistance Inhibitors: Gastric cancer can be drug resistant at the outset of treatment or develop drug resistance after treatment. Several drugs are being tested to determine if they will overcome or prevent the development of multiple drug resistance in esophageal cancer and other cancers.

Gene Therapy: Currently, there are no gene therapies approved for the treatment of gastric cancer. Gene therapy is defined as the transfer of new genetic material into a cell for therapeutic benefit. This can be accomplished by replacing or inactivating a dysfunction gene or replacing or adding a functional gene into a cell to make it function normally. Gene therapy has been directed towards the control of rapid growth of cancer cells, control of cancer death or efforts to make the immune system kill cancer cells. A few gene therapy studies are being carried out in patients with refractory gastric cancer. If successful, these therapies could be applied to patients with earlier stage disease.


Bang Y-J, Van Cutsem E, Feyereislova A et al. Trastuzumab in combination with chemotherapy versus chemotherapy alone for treatment of HER2-positive advanced gastric or gastro-oesophageal junction cancer (ToGA): a phase 3, open-label, randomised controlled trial. Lancet. 2010; 376:687-697.