Guide Treatment and Management Decisions with Genetic Testing

Gastric cancer

Knowing if your gastric cancer was brought on by an inherited mutation will provide information that will help you in your journey. Your results will provide your physician with information that will personalize your treatment and risk management decisions to be specific to your cancer.

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Myriad Onocology's Tests for Gastric Cancer and What Answers They Provide:

Hereditary cancer testing

myRisk genetic testing

Myriad myRisk® is a gene panel that helps identify your options for treatment, your risk of additional cancers, and if any close family members may be at an elevated risk of developing cancer.

Hereditary cancer risk associated with gastric cancer

Some gastric cancer cases are caused by genes passed down from your parents. Mutations in the BRCA1 and BRCA2 genes can increase your risk of gastric cancer. Lynch syndrome is another inherited condition that increases the risk of gastric cancer.1

Hereditary diffuse gastric cancer is another inherited syndrome that greatly increases the risk of developing stomach cancer. This condition is rare, but the lifetime stomach cancer risk among affected people is about 70% to 80%. This condition is caused by mutations in the CDH1 gene.2-3

Genetic testing for gastric cancer can help your family members understand their inherited risks and can help you and your doctor make fully informed treatment decisions.

To see if genetic testing will benefit you, take The Hereditary Cancer Quiz. It is time to take control of your health.

What is Gastric Cancer?4

When abnormal cells within the stomach grow out of control it’s called gastric cancer. Depending on where in the stomach cancer appears, it may have different symptoms and may require different treatments. Stomach cancers tend to develop slowly, sometimes over many years. Symptoms of stomach cancer often do not appear until the disease is advanced, which means only about 1 in 5 stomach cancers in the United States is found at an early stage,(4) making them more difficult to treat.

There are four major forms of gastric cancer:


Over 90% of cancers of the stomach are adenocarcinomas.(4) These cancers develop from the cells that form the innermost lining of the stomach.


These are cancers of the immune system tissue that are sometimes found in the wall of the stomach. The treatment and outlook depend on the type of lymphoma.

Gastrointestinal Stromal Tumor

These rare tumors start in very early forms of cells in the wall of the stomach called interstitial cells.

Carcinoid tumor

These tumors start in hormone-making cells of the stomach. Most of these tumors do not spread to other organs. Because gastric cancer begins in the stomach, it can be hard to pinpoint when it spreads to other organs. A genetic screening can help identify if you may be at higher risk for gastric cancer so your healthcare professional can diagnose it sooner.

Gastric Cancer Signs and Symptoms4

People may experience different symptoms and signs of gastric cancer because it can develop in different parts of the stomach. Early-stage gastric cancer rarely causes symptoms, which is one of the reasons stomach cancer is so hard to detect early.

Common signs and symptoms of gastric cancer:

  • Poor appetite
  • Weight loss
  • Stomach and abdominal pain
  • Vague discomfort in the abdomen, usually above the navel
  • A sense of fullness in the upper abdomen after eating a small meal
  • Heartburn or indigestion
  • Nausea
  • Vomiting, with or without blood
  • Swelling or fluid build-up in the abdomen
  • Blood in the stool

Some of these symptoms can be caused by issues other than cancer, such as a stomach virus or an ulcer. They may also occur with other types of cancer.

Gastric Cancer Diagnosis and Staging


If you have symptoms of gastric cancer, your healthcare professional may advise an upper endoscopy. This is the main way doctors look for signs of stomach cancer. This test is performed by inserting a small video camera down the throat to look at the stomach. If something suspicious is found, they may recommend a biopsy or electronic imaging for further testing.

Once a diagnosis has been confirmed, your healthcare professional will determine if it has spread. This is called staging. Staging is a process to identify where the gastric cancer is located, how much it has grown, and where it has spread.


The staging system most often used for gastric cancer is the American Joint Committee on Cancer (AJCC) TNM system, which is based on 3 key pieces of information:

  • The extent (size) of the tumor (T): How far has the cancer grown into the 5 layers of the stomach wall? Has the cancer reached nearby structures or organs?
  • The spread to nearby lymph nodes (N): Has the cancer spread to nearby lymph nodes?
  • The spread (metastasis) to distant sites (M): Has the cancer spread to distant lymph nodes or distant organs such as the liver or lungs?

Gastric Cancer Treatment Options4

Gastric cancer is difficult to treat and may require surgery to remove. Surgery may remove the cancer and part of or all of the stomach and some nearby lymph nodes. The surgeon will try to leave behind as much normal stomach as possible.

The type of operation usually depends on what part of the stomach the cancer is in and how much cancer is in the surrounding tissue. Different kinds of surgery can be used to treat stomach cancer:

Endoscopic Resection

An endoscope, a long, flexible tube with a small video camera on the end, is inserted down the throat and into the stomach. Surgical tools are passed through the endoscope to remove the tumor and part of the normal stomach wall around it.

Subtotal Gastrectomy

Also called a partial gastrectomy, this is a surgery where only part of the stomach is removed, sometimes along with part of the esophagus or the first part of the small intestine. The remaining section of stomach is then reattached. 

Total Gastrectomy

The surgeon removes the entire stomach, nearby lymph nodes, and omentum, and may remove the spleen and parts of the esophagus, intestines, pancreas, or other nearby organs. The end of the esophagus is then attached to part of the small intestine. 

Your healthcare professional may combine surgery with other treatments like chemo and radiation therapy. When used together, these treatments can help kill cancer cells that were left behind. Stomach surgery can change how and how much you eat. Talk with your doctor about all the risks, side effects, and benefits of each treatment.

  1. Giardiello FM, et al. Guidelines on Genetic Evaluation and Management of Lynch Syndrome: A Consensus Statement by the US Multi-Society Task Force on Colorectal Cancer. Am J Gastroenterol. 2014 109:1159-79. PMID:25070057.

  2. U.S. National Library of Medicine. Hereditary Diffuse Gastric Cancer. U.S. National Library of Medicine, 2020.

  3. Lynch HT, et al. Hereditary colorectal cancer. N Engl J Med. 2003 Mar 6;348(10):919-932.

  4. American Cancer Society. Cancer Facts and Figures 2020. Atlanta, Ga: American Cancer Society; 2020.

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