Zollinger-Ellison Syndrome (ZES)


Zollinger-Ellison syndrome (ZES) is sometimes known as gastrinoma, pancreatic ulcerogenic tumor syndrome or Z-E syndrome.

ZES is a rare condition that is usually diagnosed in patients between the ages of 20 and 60. This disease causes a tumor or multiple tumors to form in the upper part of your small intestine (duodenum), the lymph nodes next to your pancreas, or in your pancreas. These tumors cause your stomach to produce too much acid which can lead to ulcers, diarrhea, and more. In addition, these tumors are cancerous, or have the potential to become cancerous, and the cancer can spread if not treated or removed.

At Loma Linda University Health, we are uniquely qualified to treat Zollinger-Ellison syndrome. We treat more pancreatic disorders than any other center in the region.


Signs and symptoms of Zollinger-Ellison syndrome may include:

  • Stomach pain
  • Decreased appetite
  • Feeling full too soon
  • Nausea and vomiting
  • Diarrhea
  • Burning, aching, or gnawing in the upper abdomen
  • Heartburn and acid reflux
  • Unintended weight loss
  • Bleeding in your digestive tract
  • Black or tarry stool
  • Blood in the stool
  • Weakness
  • Fatigue


The cause of Zollinger-Ellison syndrome is unknown. However, in approximately 25% of those affected, ZES occurs in association with a genetic syndrome known as multiple endocrine neoplasia type 1 (aka MEN-1).


Diagnosis of Zollinger-Ellison syndrome starts with a medical exam and health history. Doctors may order lab work, including a blood test to check for high levels of a certain hormone that is associated with ZES.

Patients should tell the doctor if they have used over-the-counter, acid-reducing medications. Often, these medications may mask the symptoms of ZES. This could lead to a misdiagnosis or delay the diagnosis.


At Loma Linda University, our Gastroenterology and Hepatology department provides state-of-the-art, patient-centered care for those suffering from digestive disorders such as Zollinger-Ellison syndrome. Zollinger-Ellison syndrome is typically treated with medication, surgery or a combination of the two.

Treatment of Excess Acid Production

Medications known as proton pump inhibitors are powerful drugs that reduce acid by blocking the action of the tiny "pumps" within acid-secreting cells, and they are the first line of treatment.

Long-term use of prescription proton pump inhibitors, especially in people age 50 and older, has been associated with an increased risk of fractures of the hip, wrist, and spine, according to the Food and Drug Administration. This risk is small and should be weighed against the acid-blocking benefits of these medications.

Treatment of Tumors

An operation to remove the tumors that occur in Zollinger-Ellison may be necessary. Our board-certified specialists have the skills to locate even the smallest of tumors even though they are often difficult to find.

If you have just one tumor, your doctor may be able to remove it surgically, but surgery may not be an option if you have multiple tumors, or tumors that have spread to your liver. On the other hand, even if you have multiple tumors, your doctor may still recommend removing a single large tumor.

Doctors may advise other treatments to control tumor growth, including:

  • Debulking - In this procedure, the doctor removes as much of a liver tumor as possible.
  • Embolization or radiofrequency ablation - This treatment attempts to destroy the tumor by cutting off the blood supply or by using heat to destroy cancer cells.
  • Injecting medications - Drugs are injected into the tumor to relieve cancer symptoms.
  • Chemotherapy - The goal of chemotherapy is to slow tumor growth.
  • Enucleation - Many small ulcers in the pancreas may be treated by “scooping out” alone. This is a procedure of choice for patients that have small tumors (less than 1cm) where the tumor is located on the surface of the pancreas.
  • Resection of the pancreas - In patients with large tumors, a distal pancreatectomy or a Whipple operation may be performed, depending on where the tumor is located in the pancreas.
  • Duodenal exploration - Tumors often occur in the wall of the duodenum (first part of the intestine). Therefore, opening the duodenum and carefully feeling it to remove any tumors in this area is important.
  • Lymph nodes - In some patients, the tumor may be located in the lymph glands outside the pancreas. When this happens, careful palpation and removal of these glands is important at the time of surgery.
  • Liver transplant - In some cases, a patient may need to undergo a liver transplant.

In addition, genetic counseling may be beneficial for patients and their families.


If Zollinger-Ellison syndrome is left untreated, complications may include continued pain, diarrhea, and weight loss. If ZES is left untreated, further complications include the possible spread of cancer and the need for more complex and unpleasant treatments that may have been avoided. Ultimately, failing to seek treatment for ZES can be fatal.


Anyone can develop Zollinger-Ellison syndrome. However, in about 25% of those affected by ZES, it may be caused by an inherited condition called multiple endocrine neoplasia type 1. This is also known as MEN-1.

Those who have a parent, sibling, or another blood relative with MEN-1 may be at greater risk for developing ZES.


Seek medical intervention. If you are experiencing symptoms like those associated with ZES, seek medical intervention right away. Being proactive is important, and it starts with a medical evaluation. To request an evaluation at Loma Linda University Health, contact this department or schedule the appointment through MyChart.

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