CDH1 Gene

February 13, 2026

This page was reviewed under our medical and editorial policy by Heather Hampel, M.S., C.G.C., professor, Department of Medical Oncology & Therapeutics Research, City of Hope^® Cancer Center Duarte.

The CDH1 gene is found in all men and women. This gene contains genetic instructions for creating the epithelial cadherin or E-cadherin (CDH1) protein.

When functioning as it should, the CDH1 protein helps cells connect to one another to form tissues. CDH1 also helps to stop tumors from growing (tumor suppression) and plays a role in gene activation, cell growth and movement, and chemical transmission of signals in cells, all important functions in the body’s cells.

This guide to the CDH1 gene and its role in cancer risk will help patients learn more.

What Is a CDH1 Mutation?

In some people, mutations may occur in the CDH1 gene. This means the gene’s instructions, or DNA sequence, has been altered and the gene is not working as it should. More than 120 different harmful changes have been found to occur in the CDH1 gene and increase the risk for developing cancer.

These mutations may be either inherited, meaning they are passed down from parent to child, or they may be acquired. Acquired, or somatic, mutations are caused by cell changes that occur during a person’s life and are not inherited from parents.

Both inherited and acquired CDH1 mutations may increase a person’s risk for developing cancer. Inherited CDH1 changes may cause a condition called hereditary diffuse gastric cancer (HDGC), a disorder that increases a person’s chances of developing diffuse gastric cancer and lobular breast cancer.

CDH1 Gene Mutation and Cancer Risk

Mutations to CDH1 are linked to the following cancers.

Stomach cancer: Patients with HDGC caused by CDH1 mutations have up to a 70% lifetime risk for developing a specific type of stomach cancer called diffuse gastric cancer.

Lobular breast cancer: This type of cancer originates in the mammary glands. For women with HDGC, it is estimated they have a 40% to 55% lifetime risk for developing lobular breast cancer.

Patients with an increased risk may benefit from more frequent screening, beginning screening at a younger age or risk-reducing surgeries. Because it is difficult to screen for this specific type of gastric cancer, patients with CDH1 mutations may need to have their stomach removed to prevent the development of diffuse gastric cancer. In addition, some women at this level of breast cancer risk consider getting risk-reducing mastectomies. These are personal decisions that will be discussed with a team of physicians to help patients weigh the risks, benefits and limitations of these surgeries.

Patients who have already been diagnosed with cancer may benefit from testing, as the results may help doctors create a personalized treatment plan. Their family members may also wish to speak to a genetic counselor and consider CDH1 genetic testing, as this may help them better understand their own cancer risk.

Who Is a Candidate for CDH1 Genetic Testing?

CDH1 gene testing may be recommended for patients who have a personal or family history of certain cancer types.

Patients with diffuse gastric cancer diagnosed at any age meet testing criteria for CDH1. Risks may be higher in individuals who have diffuse gastric cancer and any of the following:

• They have a cleft lip or cleft palate and/or have a close family relative who also has a cleft lip or cleft palate
• They are of Maori descent
• They were diagnosed under age 49
• They have also been diagnosed with lobular breast cancer before age 69

Patients with lobular breast cancer and a personal or family history of diffuse gastric cancer also meet criteria for testing.

For patients with a family history of cancer, CDH1 testing may be recommended for people with at least two family members with gastric cancer, with at least one diagnosed at age 50 or younger and at least one confirmed to have diffuse gastric cancer at any age.

It may be confusing to understand who should get tested for CDH1 mutations, so patients should discuss testing with their care team to find out more.

Cost of CDH1 Gene Testing

In most cases, a multi-gene panel test will be ordered. This type of test checks several genes at the same time and may be useful when a family has no known gene mutations. Some of the genes that are typically included in multi-gene panel tests for diffuse gastric cancer are CDH1 and CTNNA1.

Multi-gene panel testing may be covered by health insurance if the patient meets testing criteria and it is recommended by a patient’s doctor. However, patients should contact their insurance provider to find out more.

As an alternative, patients may wish to pay out of pocket for CDH1 testing. Self-pay costs vary, depending on the laboratory, but typically range from $250 to $400.

CDH1 Test Results

After CDH1 testing, the results may be ready in about two to three weeks, although this may vary. During an appointment, the patient’s doctor will let them know their results and what they mean for their cancer treatment or future cancer risk.

A positive test: This means a CDH1 mutation (harmful genetic change) linked to an increased risk of diffuse gastric and lobular breast cancer was found. For patients testing positive, additional screening, risk-reducing surgeries and preventive lifestyle changes may be recommended.

A negative test: This result is especially helpful in families with a known CDH1 genetic mutation because it means the person tested did not inherit it. This result is known as a true negative. It means the person’s cancer risk is about the same as that of the general population.

When a person has a strong family history of diffuse gastric and/or lobular breast cancer but has no associated gene mutation, the negative result is known as an uninformative negative. This means a genetic mutation may be still involved, but it was not detected by current technology. Doctors may recommend further testing or check-ups as new technology becomes available.

An inconclusive result: This means a genetic change was found, but there is not yet enough information to know whether it increases cancer risk. This type of genetic change is referred to as a variant of uncertain significance (VUS). People with this finding are urged to stay in touch with their provider in case new information becomes available about their variant over time.

Not all gene variations, or mutations, have been studied. Meeting with a genetic counselor to go over the pros and cons of testing may help patients understand the limitations of each test.