What are the symptoms of gastrinoma?

Gastrinoma is similar to ulcer disease, but it lasts longer and is more difficult to treat than ulcer. The most common symptoms are upper abdominal pain and burning sensation, accompanied by diarrhea. A large proportion of people also suffer from symptoms of reflux esophagitis.

1. Ulcer disease

The most common clinical manifestation of gastrinoma is multiple peptic ulcers, with the main complaints being upper abdominal pain, burning sensation, etc. The symptoms are similar to those of ordinary ulcers, but are often more persistent and stubborn, and the commonly used drugs for the treatment of ulcers have poor efficacy.

75% of peptic ulcers are located in the first segment of the duodenum, and 25% occur in atypical locations, such as the retrobulbar duodenum and jejunum. Some patients develop lower esophageal ulcers due to reflux esophagitis. Most ulcers are single, but multiple ulcers may also occur. Since gastrin is the "nutritional hormone" of the stomach, the ulcers in patients with gastrinoma are generally less than 1 cm in diameter, but sometimes may reach or exceed 2 cm, and may even be huge ulcers.

Commonly used drugs for treating ulcers are temporarily effective, but they are very prone to recurrence. Recurrent ulcers often lead to serious complications, such as upper gastrointestinal bleeding and/or perforation, fistula formation, etc., which may necessitate surgical treatment. However, because the gastrinoma was not removed during surgery, the ulcer recurred rapidly after the operation, often at the anastomosis or the duodenum or jejunum below. The characteristics of ulcers in this disease are: stubbornness, multiple occurrence, atypical location, and high incidence of complications.

When peptic ulcer is accompanied by the above phenomena, it is necessary to suspect the presence of gastrinoma and serum gastrin should be measured.

2. Diarrhea

Diarrhea occurs in 1/4 to 1/3 of patients. Most of them are watery diarrhea, ranging from 10 to 30 times per day. Diarrhea often occurs at the same time as ulcer symptoms, or before ulcer symptoms. 5% to 10% of patients only have diarrhea without ulcers. Excessive gastric acid secretion stimulates pancreatic lipase and excessive acidity in the gastric cavity causes microscopic or visible damage to the intestinal mucosal surface, which is the main cause of diarrhea. When gastric juice is aspirated with a gastric tube, diarrhea can be significantly improved, which is a characteristic of gastrinoma diarrhea. Gastrinoma can also cause steatorrhea, and in severe cases it can lead to fat absorption disorders. As a large amount of acidic gastric juice enters the small intestine, the pH of the upper small intestine decreases significantly, lipase is inactivated in the acidic environment, and the decomposition of triglycerides is reduced, leading to fat absorption disorder.

3. Multiple endocrine neoplasia syndrome

10%~40% of gastrinoma patients have other endocrine tumors concurrently, which is multiple endocrine neoplasia type Ⅰ (MEN-1). Hyperparathyroidism is the most common complication. In addition, it may also be combined with adenomas of the pituitary, adrenal glands, and thyroid glands, and may also be combined with carcinoids of the bronchi and small intestine. Pheochromocytoma is rare.

Reflux esophagitis

33% to 61% of gastrinoma patients have esophageal reflux symptoms, and 42% have esophageal abnormalities under endoscopy, of which 8% have severe lesions with ulcers, stenosis, and Barrett's esophagus.