Effective endoscopic management of gastric neoplastic complications in patients with autoimmune gastritis: results of a monocentric study of 88 patients.

Background: We evaluated the efficacy of endoscopic treatment (ET) for gastric neoplastic complications of autoimmune gastritis (AIG). We also assessed the safety of ET and the risk factors for the occurrence of neuroendocrine tumors (NETs) and gastric adenocarcinoma (GA).

Methods: This was a retrospective, single-center, observational study. All patients diagnosed with AIG between 1987 and 2019 and had at least 1 upper endoscopy available were included.

Results: The study population comprised 88 patients (68.2% female). The median follow up was 5 years (range 1-28). A total of 132 NETs were diagnosed in 39/88 patients (44.3%) (median age 50.0 years, range 27.0-85.0 years). The mean lesion size was 7.1 mm (range 1-30); there were 80 G1 NETs and 52 G2 NETs. Among the 132 lesions, 86.3% (114/132) were endoscopically resected, mostly by endoscopic mucosal resection (105/114, 92.1%), without complications. Only 1 patient underwent surgery. Twelve patients (13.6%) (7 females; median age, 76.0 years; range, 53.0-90.0 years) presented with GA. Of these, 66.7% (8/12) needed surgery, while 4 patients underwent exclusive endoscopic resection. Only 2 patients presented with NETs and GA (2.8%). Patients who presented with NETs were significantly younger at AIG diagnosis than patients with GA: 52.0 (18.0-85.0) vs. 67.0 (44.0-81.0) years (P=0.008). Patients who presented with GA were significantly older than those who presented with NETs: 76.0 (53.0-90.0) vs. 50.0 (27.0-85.0) years (P<0.001).

Conclusion: ET of NETs for AIG is effective and safe. GA is rarer, occurs in significantly older patients, and usually requires surgery.