Type 1
Type 1 is the most common. These are associated with atrophic gastritis and an overproduction of gastrin (hypergastrinaemia). These are small polyps (less than 1–2 cm) that are sometimes found during a gastroscopy. These polyps may not be cancerous, but they may recur. They can be removed and a regular follow-up plan put in place. Long-term use of proton pump
inhibitors (anti-acid medications) for gastric reflux or dyspepsia may increase risk of this type of Neuroendocrine Cancer.
Type 2
These are uncommon and may occur as part of an inherited condition
known as multiple endocrine neoplasia type 1 (MEN 1): when excessive secretion of the hormone gastrin by a tumour (gastrinoma) causes overproduction of stomach acid. This is known as Zollinger–Ellison syndrome. These tumours in the stomach are often small and are often simply monitored with endoscopic ultrasound.
Type 3
These uncommon tumours are often larger (>2 cm) and can spread to other parts of the body (metastasise). They need to be surgically removed.
Type 4
Type 4 is a very rare type of gastric Neuroendocrine Cancer and is the most difficult to treat.
Tumours are often large and may have spread (metastasised) at diagnosis.