Summary about Disease
Gastrinoma is a rare type of tumor, usually found in the pancreas or duodenum (the first part of the small intestine), that produces excessive amounts of gastrin. Gastrin is a hormone that stimulates the stomach to produce hydrochloric acid. The excessive gastrin leads to overproduction of stomach acid, causing peptic ulcers, gastroesophageal reflux disease (GERD), and other digestive problems. Gastrinomas are often cancerous and may spread to other parts of the body. They are a type of neuroendocrine tumor.
Symptoms
Abdominal pain (often severe)
Diarrhea
Heartburn
Nausea and vomiting
Bleeding in the digestive tract (leading to anemia or bloody stools)
Weight loss
Fatigue
Loss of appetite
Rarely, symptoms from tumor spread like jaundice if it affects the liver.
Causes
The exact cause of gastrinomas is not fully understood. Most gastrinomas occur sporadically, meaning they develop without a clear inherited cause. However, some cases are associated with Multiple Endocrine Neoplasia type 1 (MEN1), a rare inherited disorder that causes tumors in various endocrine glands.
Medicine Used
Proton Pump Inhibitors (PPIs): These are the primary medications used to reduce stomach acid production (e.g., omeprazole, lansoprazole, pantoprazole, esomeprazole). Higher doses than typically used for GERD are often required.
Octreotide or Lanreotide: Somatostatin analogs that can reduce gastrin secretion and slow tumor growth, particularly in patients with metastatic disease.
Chemotherapy: May be used for metastatic gastrinomas.
Streptozotocin and Doxorubicin: Other Chemotherapeutics used for Gastrinoma.
Is Communicable
No, gastrinoma is not communicable. It is not an infectious disease and cannot be spread from person to person.
Precautions
Since the exact cause is often unknown, there are no specific precautions to prevent sporadic gastrinomas. If you have a family history of MEN1, genetic testing and regular screening may be recommended. For those diagnosed with a gastrinoma:
Follow your doctor's treatment plan meticulously.
Maintain a healthy lifestyle, including a balanced diet and regular exercise (as tolerated).
Avoid smoking and excessive alcohol consumption, as these can worsen digestive symptoms.
Report any new or worsening symptoms to your healthcare provider promptly.
How long does an outbreak last?
Gastrinoma isn't an outbreak, it's a tumor. Symptoms are chronic and persist until the underlying gastrinoma is effectively treated or managed. Without treatment, symptoms related to hyperacidity and tumor growth will continue. The duration of symptoms depends on how quickly the diagnosis is made, how aggressive the tumor is, and how effective the treatment is.
How is it diagnosed?
Fasting Serum Gastrin Level: Elevated gastrin levels in the blood are a key indicator.
Gastric Acid Analysis: Measuring stomach acid output.
Secretin Stimulation Test: Secretin is a hormone that normally inhibits gastrin release, but in gastrinoma, it paradoxically stimulates gastrin release. This test is highly specific.
Imaging Studies:
Endoscopic Ultrasound (EUS): To visualize tumors in the pancreas and duodenum.
CT Scan and MRI: To detect tumors and assess for metastasis.
Somatostatin Receptor Scintigraphy (SRS) or PET/CT with Gallium-68 DOTATATE: To locate tumors that express somatostatin receptors.
Upper Endoscopy: To visualize the duodenum and look for ulcers or tumors.
Timeline of Symptoms
The timeline of symptoms can vary significantly from person to person. Some individuals may experience mild symptoms for a long period before diagnosis, while others may have a rapid onset of severe symptoms.
Early stages: Intermittent abdominal pain, mild heartburn, and occasional diarrhea might be the initial presentation. These symptoms can be mistaken for common digestive issues.
Progressive stages: As the gastrinoma grows and gastrin levels increase, symptoms become more persistent and severe. This can include chronic abdominal pain, severe diarrhea, weight loss, vomiting, and complications from peptic ulcers (such as bleeding).
Late stages (if the tumor spreads): Symptoms related to metastasis may appear, such as jaundice (if the liver is affected) or other systemic symptoms.
Important Considerations
MEN1 Screening: If a gastrinoma is diagnosed, especially in a younger individual, screening for MEN1 syndrome is crucial.
Localization of the Tumor: Accurately locating the gastrinoma is essential for surgical planning. EUS and SRS or PET/CT are important tools.
Surgical Resection: Surgery is the primary treatment option for localized gastrinomas. Complete resection offers the best chance for cure.
Management of Metastatic Disease: If the gastrinoma has spread, treatment focuses on controlling symptoms and slowing tumor growth. Options include medications (PPIs, somatostatin analogs, chemotherapy) and targeted therapies.
Long-Term Follow-Up: Regular monitoring is necessary to detect recurrence or progression of the disease.