Initial assessment
When a gastric polyp is identified on upper gastrointestinal endoscopy, the first step is to ensure accurate endoscopic characterization and histological confirmation. Morphology (sessile or pedunculated), size, location and the presence of suspicious endoscopic features should be assessed. In parallel, representative biopsies should be obtained from the polyp and from the adjacent gastric mucosa, allowing assessment for atrophic gastritis, intestinal metaplasia or Helicobacter pylori infection, all of which influence risk and follow-up.
Histological classification
Clinical decision-making is primarily based on the histological type of the polyp, distinguishing four major groups: gastric adenomas, hyperplastic polyps, fundic gland polyps and gastric neuroendocrine tumours. This classification is decisive, as each subtype has distinct biological behaviour and neoplastic risk, requiring different strategies for resection, surveillance or further investigation.
Gastric adenoma
Gastric adenomas are premalignant lesions and should be removed endoscopically whenever identified. After complete resection, follow-up endoscopy at approximately 12 months is indicated, with subsequent surveillance adjusted according to histological risk, resection margins and background mucosa. In the presence of R0 resection and absence of extensive background gastric mucosal changes, surveillance intervals may be progressively extended.
Hyperplastic polyp
Hyperplastic polyps are usually benign, but are associated with chronic inflammation of the gastric mucosa and an increased risk of synchronous neoplasia. Eradication of Helicobacter pylori is an essential step whenever infection is present. Endoscopic resection is mainly indicated for polyps ≥10 mm, symptomatic polyps, those with dysplasia or those associated with anaemia or bleeding. Small asymptomatic polyps may be biopsied only, with follow-up determined by the risk profile of the background mucosa.
Fundic gland polyp
Fundic gland polyps are usually benign and are frequently associated with long-term proton pump inhibitor use. In the absence of dysplasia, they do not require routine systematic endoscopic surveillance. However, when they are numerous, occur at a young age, are large or show dysplasia, the possibility of hereditary syndromes should be considered, particularly familial adenomatous polyposis, with initial assessment including complete colonoscopy.
Gastric neuroendocrine tumour
Management of gastric neuroendocrine tumours depends on type (I, II or III), size, histological grade (Ki-67/mitoses) and depth of invasion. Type I and II tumours are usually associated with hypergastrinaemia and have an indolent behaviour, allowing follow-up with periodic endoscopic surveillance, with endoscopic resection reserved for larger lesions.
Type III gastric neuroendocrine tumour
Type III gastric neuroendocrine tumour is sporadic, not associated with hypergastrinaemia and has greater metastatic potential. In these cases, formal staging is indicated, including endoscopic ultrasound to assess depth of invasion and lymph node involvement, often complemented by CT or MRI. Endoscopic resection should be considered only in highly selected cases, namely lesions <10 mm, G1 (Ki-67 ≤2%) and confined to the mucosa or submucosa. In the absence of these criteria, surgery is the recommended treatment.
Maintenance and follow-up
Follow-up after identification or treatment of gastric polyps should be individualized, integrating histological type, presence of dysplasia, background mucosa and patient risk factors. A structured approach helps avoid excessive surveillance in benign lesions while ensuring early identification of situations with true neoplastic potential, aligning clinical practice with current recommendations from scientific societies.
