Yavuz Kutay GOKCE, Arif Irfan SOYKAN, Ramazan Erdem ER, Memduh OZDEN
Annals of Clinical and Analytical Medicine - 2026;17(6):543-548
Aim: Autoimmune gastritis (AIG) is associated with the immune-mediated destruction of gastric parietal cells, potentially leading to carcinoid tumors. This study examined factors associated with carcinoid tumor development in patients with AIG, with a particular focus on anti-parietal cell antibody (APCA) positivity, autoimmune comorbidities, and biochemical markers. Methods: A retrospective single-center prevalence study was conducted on 330 patients with autoimmune gastritis (AIG), categorized into carcinoid tumor-positive (n = 28) and carcinoid tumor-negative (n = 302) groups. Demographic, clinical, and biochemical parameters were compared between the groups. Patients diagnosed with Helicobacter pylori were excluded from the study. Univariate and multivariate logistic regression analyses were used to identify independent predictors. Results: Carcinoid tumors were observed in 28 patients (8.5%). APCA negativity significantly increased the risk of carcinoid tumors (OR, 2.83; 95% CI: 1.10- 7.26, p=0.030). Autoimmune comorbidities were also significant negative predictors (OR, 3.63; 95% CI: 1.20-12.65, p=0.044). Lower vitamin B12 levels independently predicted tumor risk (odds ratio [OR], 0.95; 95% CI: 0.91-1.00, p=0.043). Lower hemoglobin and ferritin levels were significant in the univariate analysis, but not in the multivariate analysis. Conclusion: APCA negativity and vitamin B12 deficiency were significantly associated with carcinoid tumors in AIG patients. Vigilant monitoring of these risk factors is essential for early tumor detection. The observation that carcinoid tumor development was reduced in patients with autoimmune comorbidity forms the basis of a new hypothesis: "The protective effect of autoimmunity against cancer."
