Gastrinoma is a type of tumor that produces too much gastrin, leading to an overproduction of stomach acid.

What are signs and symptoms of Gastrinoma?

The signs and symptoms of Gastrinoma, a type of tumor causing Zollinger-Ellison syndrome (ZES), include: - Belly pain - Chronic diarrhea - Indigestion - Heartburn - Gastrointestinal bleeding - Weight loss It is important to note that if a patient is experiencing recurring or tough-to-treat peptic ulcers, particularly in the first part of the small intestine (duodenum) and accompanied by diarrhea, doctors should consider the possibility of a gastrinoma. However, it is not necessary to screen everyone for this condition as ZES only accounts for about 0.1% to 1% of all peptic ulcer cases. Additionally, it is worth mentioning that diarrhea caused by ZES tends to improve when proton pump inhibitors (PPIs) are given, which are medications used to decrease stomach acid.

What else can Gastrinoma be?

The doctor needs to rule out the following conditions when diagnosing Gastrinoma: 1. Achlorhydria (a condition where the stomach doesn't produce any hydrochloric acid) 2. Atrophic gastritis (a long-term inflammation that damages the stomach lining) 3. Gastric outlet obstruction (a blockage from the stomach to the small intestine) 4. Peptic ulcer disease (sores that form on the lining of the stomach or upper part of the small intestine) 5. Pernicious anemia (a decrease in red blood cells due to inability to absorb vitamin B12 properly) 6. Zollinger-Ellison syndrome (a rare condition where one or more tumors form in your pancreas or the upper part of your small intestine)

How is Gastrinoma treated?

Surgery is the primary treatment for gastrinomas, particularly for patients with sporadic gastrinomas who do not have cancer spread to other parts. However, patients with multiple endocrine neoplasia type 1 (MEN1)-related Zollinger-Ellison Syndrome, which is characterized by multiple small tumors and widespread cancer, are often managed with medication. Surgical removal is recommended for MEN1-related tumors larger than 2cm. Patients not suitable for surgery or those with widely spread cancer are recommended to take proton pump inhibitors as a conservative treatment method. Chemotherapy and hormonal therapy have limited effectiveness, while other promising approaches are still pending large-scale usage and further clinical evaluation. Radiotherapy is not typically recommended.

What are the side effects when treating Gastrinoma?

The side effects when treating Gastrinoma include difficulty for the surgeon in finding the tumor during the operation, failure to get rid of all the cancerous tissue, bleeding or a hole in the intestine due to stomach or duodenal ulcers, weight loss or severe diarrhea, and the spread of cancer to other parts of the body (metastases).

Are there long term effects of Gastrinoma?

If a patient has their gastrinoma tumor completely removed, they can anticipate more than a 90% chance of surviving for 5 to 10 years. However, if the tumor removal isn't entirely successful, the prognosis decreases significantly. In these cases, the chances of surviving 5 years stands at just 43%, and further drops to a 25% chance of surviving 10 years.

What type of doctor should I see for Gastrinoma?

You should see an endocrinologist or a gastroenterologist for Gastrinoma.

Gastrinoma

What is Gastrinoma?

Gastrinomas are a type of tumor that come from cells called neuroendocrine cells. These tumors have a unique characteristic – they produce too much gastrin. Gastrin is a hormone that signals the stomach to make acid. When a gastrinoma is present, there’s too much gastrin, leading to an overproduction of stomach acid.

This overproduction can cause severe stomach ulcers, which are sores on the stomach lining, and diarrhea. When gastric ulcers and diarrhea occur together because of a gastrinoma, it’s known as Zollinger-Ellison syndrome (ZES).

What Causes Gastrinoma?

Tumors associated with the pancreas seem to develop from very early cells that can become many different types of tissue, known as endodermal pluripotent cells. Gastrinomas, a specific type of these tumors, can occur randomly (75 to 80% of the time) or be related to a genetic disorder called multiple endocrine neoplasia type 1 (MEN-1). MEN-1 is a condition passed down in families that leads to the development of tumors in hormone-producing glands and can affect 20 to 30% of cases.

This syndrome is due to changes, or mutations, in a gene that normally helps control cell growth (the MEN1 gene), and this gene is located on a specific region of chromosome 11 (11q13). Scientists believe that additional changes in the MEN1 gene contribute to the development of tumors in individuals predisposed to this condition.

Risk Factors and Frequency for Gastrinoma

Gastrinomas, a type of tumor, have an incidence of 0.5 to 3 cases per million people every year across the world. With better detection methods, doctors have been seeing more of these cases each year. Majority of these tumors, about 80% to 90%, appear in a specific area in the abdomen known as the ‘gastrinoma triangle.’ However, they can also appear in locations such as the stomach, lymph nodes around the pancreas, liver, bile duct, ovary, heart or might be linked with certain lung cancers.

Most of these gastrinomas that appear in the duodenum, a part of the small intestine, are typically smaller than 1 cm. They are generally found in the first part of the duodenum. When it comes to gastrinomas associated with certain conditions, about 50% to 88% with sporadic ZES and almost all gastrinomas with MEN1, a genetic disorder, are duodenal.

Contrarily, gastrinomas that appear in the pancreas are often bigger and make up around 25% of such tumors. They’re also the most common kind of functional and malignant tumor to affect the hormone-producing part of the pancreas.

Generally, gastrinomas are found in individuals between the ages of 20 and 50, and it’s slightly more common in men. For people with MEN1, these tumors are often detected at a younger age, usually between 10 and 30 years. Though gastrinomas grow slowly, about 60% are cancerous and have already spread by the time of diagnosis.

Signs and Symptoms of Gastrinoma

Zollinger-Ellison syndrome (ZES) often presents with symptoms like belly pain and chronic diarrhea. Some people also experience indigestion, heartburn, gastrointestinal bleeding, or weight loss. If a patient is battling recurring or tough-to-treat peptic ulcers, particularly if they’re in the first part of the small intestine (duodenum) and accompany diarrhea, doctors should consider the possibility of a gastrinoma, which is a type of tumor causing ZES. However, it’s important to bear in mind that ZES only accounts for about 0.1% to 1% of all peptic ulcer cases, so it’s not necessary to screen everyone for this condition. A noteworthy point about diarrhea caused by ZES is that it seems to get better when proton pump inhibitors (PPIs) are given, which are medications used to decrease stomach acid.

Testing for Gastrinoma

If your doctor suspects that you may have a Zollinger-Ellison Syndrome (ZES), which is a condition where one or more tumors form in your pancreas or the upper part of your small intestine, they may order specific tests to confirm this. These tests involve checking the level of a hormone, gastrin, in your blood. If your blood shows an increased amount of gastrin together with an increased amount of stomach acid or low stomach PH, this could confirm the diagnosis of ZES. However, it is important to know that a normal gastrin level can rule out ZES.

There are other conditions that can also lead to high gastrin levels, including certain medications like proton pump inhibitors (PPIs), elevated calcium levels in the blood, chronic inflammation of the stomach lining (atrophic gastritis), or a blockage at the stomach outlet. Because of this, your doctor may also want to analyze your stomach acid secretion.

Additionally, a hormone called chromogranin A is often measured as it can mark the presence of certain types of tumors, including gastrinomas (tumors associated with ZES). This hormone amount can also give an idea about the size of a tumor and help predict its behavior, which is useful for disease management and monitoring.

Other than blood tests, your doctor may also want to get detailed images of your internal organs to locate the tumor and understand how far, if at all, it has spread. This is typically done using methods such as computed tomography (CT), magnetic resonance imaging (MRI), and techniques involving radioactive tracers (somatostatin receptor scintigraphy with SPECT/CT and gallium-somatostatin analog PET-CT). Endoscopy can help detect small tumors that might be missed otherwise. In some cases, however, the tumor can only be located during a surgical procedure (laparotomy).

Patients with ZES are often assessed for multiple endocrine neoplasia type 1 (MEN 1) syndrome, a disorder that affects your endocrine glands (glands that produce hormones) and can lead to the development of tumors in these glands. This is diagnosed based on history, including any history of elevated blood calcium levels (hypercalcemia), kidney stone formation (nephrolithiasis), and tumors of the pituitary gland along with the patient’s family history. Other non-hormone related symptoms of MEN 1 include skin disorders like angiofibromas (small, benign bumps on the skin) and collagenomas (skin tumors linked to collagen, the protein that gives our skin structure).

Treatment Options for Gastrinoma

The primary aim of medical treatment is to manage symptoms and prevent complications of peptic ulcer disease. The most recommended medication includes proton pump inhibitors, often consumed in high dosages. The preference for proton pump inhibitors over H2 receptor blockers is because they’re more potent, and they last in the system longer.

Surgery is the only permanent solution for gastrinomas, which are tumors that produce too much acid in the stomach. Patients with a sporadic gastrinoma who do not have cancer spread to other parts cannot be cured should be referred for surgery. However, most patients with multiple endocrine neoplasia type 1 (MEN1)-related Zollinger-Ellison Syndrome, a condition characterized by multiple small tumors, widespread cancer, and minimal chances of surgical cure, are often managed with medication. Still, if the tumors related to MEN1 are larger than 2cm, surgical removal is recommended.

Cancer spreading (metastasis) and its extent are the most critical factors affecting survival. The purpose of surgery is to remove the primary tumor for a possible cure, lower the risk of cancer spread, and enhance survival. For non-spread gastrinomas located in the pancreas, surgical removal is usually an effective method. If the gastrinomas are found in the duodenum (part of the small intestine), they tend to be multiple, hence often necessitating the removal of the duodenum. Lymph nodes in the area should be routinely checked during the procedure. Patients undergoing surgery should receive proton pump inhibitors. Regular yearly check-ups with blood tests and imaging, as needed, are recommended after the tumor removal.

Patients not suitable for surgery or those with widely spread cancer are recommended to take proton pump inhibitors as a conservative treatment method.

Treatment options for patients with cancer spread have limited effectiveness. Chemotherapy is an available choice for patients with widespread cancer spread. There are specific combinations of drugs that are used, but they’ve been found to provide limited improvement and can cause considerable side effects. Hormonal therapy, which is known to decrease stomach acid production, does not show any anti-cancer activity. Other promising approaches in the treatment of pancreatic neuroendocrine tumors (tumors that begin in the hormone-producing cells of the pancreas) target the growth factor receptors and their related signaling pathways. These strategies have shown promising results in delaying cancer progression in some clinical trials but are still pending large-scale usage and further clinical evaluation. Other treatments include blocking the blood supply to liver cancer and using human leukocyte interferon, an immune protein. As a rule, radiotherapy is not typically recommended.

Here are some medical conditions to be aware of:

Achlorhydria (a condition where the stomach doesn’t produce any hydrochloric acid)
Atrophic gastritis (a long-term inflammation that damages the stomach lining)
Gastric outlet obstruction (a blockage from the stomach to the small intestine)
Peptic ulcer disease (sores that form on the lining of the stomach or upper part of the small intestine)
Pernicious anemia (a decrease in red blood cells due to inability to absorb vitamin B12 properly)
Zollinger-Ellison syndrome (a rare condition where one or more tumors form in your pancreas or the upper part of your small intestine)

What to expect with Gastrinoma

If a patient has their tumor completely removed, they can anticipate more than a 90% chance of surviving for 5 to 10 years. However, if the tumor removal isn’t entirely successful, the outlook decreases significantly. In these cases, the chances of surviving 5 years stands at just 43%, and further drops to a 25% chance of surviving 10 years.

Possible Complications When Diagnosed with Gastrinoma

Possible complications of surgery to remove a tumor include:

Difficulty for the surgeon in finding the tumor during the operation
Failure to get rid of all the cancerous tissue
Bleeding or a hole in the intestine due to stomach or duodenal ulcers
Weight loss or severe diarrhea
The spread of cancer to other parts of the body (metastases)

Preventing Gastrinoma

It’s important for patients to know that these growths can often be successfully treated if discovered early. Taking your medication as directed by your doctor is crucial for successful treatment and to prevent complications related to these growths.