What Is Hereditary Diffuse Gastric Cancer?

Medically Reviewed by Melinda Ratini, MS, DO on April 27, 2024
3 min read

If your doctor talks about the possibility of hereditary diffuse gastric cancer (HDGC), there's a lot of information to take in. It could be that someone in your family has been diagnosed with this rare type of stomach cancer, or you may already have it yourself.

Your doctor may suggest you get surgery. Listen carefully to their recommendations, and talk things over with your family or close friends. It's important to get their support to help you manage the wave of emotions that can go along with a cancer diagnosis. And because this disease runs in families, you'll need to reach out to your relatives to discuss the cancer risks that they may face.

You get HDGC because of a change -- called a mutation -- in a gene that's passed on from one of your parents. The gene is called CDH1.

The majority of people with this gene mutation get HDGC, often by about age 40.

If you're diagnosed with HDGC but tests don't show that you have a CDH1 mutation, it's likely that you have another gene change that made you more likely to get the cancer.

With HDGC, cancer cells multiply under the lining of your stomach. That leads to a cancer that's spread out -- or "diffuse" -- rather than a solid tumor. This also makes it more likely that the cancer will spread to other areas, including your liver and bones.

Since the cancer cells linked with HDGC are lodged in the lining of your stomach, it's not easy for a doctor to spot them, even if you get an endoscopy procedure that uses a camera to see inside your digestive system. A lot of times, HDGC isn't diagnosed until the disease is in its late stages.

Some of the symptoms you may have are:

If the cancer spreads to other parts of your body, you may also get:

  • Yellowing of the eyes and skin (jaundice)
  • Fluid buildup in your belly
  • Firm lumps under your skin
  • Broken bones


The only sure way to prevent HDGC if you have the gene mutation is to have surgery to remove your stomach. You may hear your doctor call this a "total gastrectomy." This surgery is also the treatment when HDGC has already been found in your stomach.

During the operation, your surgeon connects your esophagus -- a tube that runs from your throat to your stomach -- to your small intestine. That way, your digestive system still works, even without your stomach.

If HDGC has already spread to other organs, your doctor may suggest other treatments like chemotherapy, radiation, or targeted drugs.

Some people decide not to have a gastrectomy, or it may not be a good choice because they have other long-term diseases. In these cases, doctors will recommend that you get regular tests for new stomach tumors, as well as make lifestyle changes. They'll suggest you get more exercise, eat more fruits and vegetables, and avoid salted, cured, and preserved foods. And if you smoke, you'll need to stop.

If someone in your family has been diagnosed with HDGC, a doctor may recommend that you get genetic testing to find out whether you have a gene change that makes it more likely that you'll get the cancer.

The same gene changes that make you more likely to get HDGC also may raise your odds of getting other cancers, including lobular breast cancer, prostate cancer, and colorectal cancers.

If you get a diagnosis of HDGC, make sure you get the emotional backing you need -- before and after treatment. Your doctor can help you get in touch with support groups, where you can meet and talk to others who are going through the same things you are. You can also find online groups where you can get tips and learn from others.