Case study: Gastric ulcer mimicking malignancy

A 66-year-old man presented with a 2-week history of intermittent epigastric pain and was found to have a large gastric ulcer initially concerning for malignancy. Further evaluation ultimately revealed gastric IgG4-related disease (IgG4-RD), a rare but important diagnostic consideration.

The in-press case study from Gastroenterology was reported by MMed Yue Chen, of the Department of Gastroenterology and Hepatology, Xiamen University in China, and colleagues.

The patient had a history of hypertension and hyperuricemia and denied lengthy NSAID use, alcohol consumption, or smoking. Physical examination was unremarkable.

Laboratory studies demonstrated normocytic anemia (hemoglobin 88 g/L), peripheral eosinophilia, and hypoalbuminemia. Immunologic testing revealed elevated total IgG and markedly increased IgE levels, with positive anti-Ro52 antibodies. Tumor markers were within normal limits, and infectious workup, including parasitic evaluation, was negative.

Cross-sectional imaging and FDG PET–CT identified a gastric lesion suspicious for malignancy. Upper endoscopy confirmed a large ulcer with features concerning for advanced gastric cancer.

Initial and repeat endoscopic biopsies demonstrated inflammatory changes and fungal elements but no evidence of malignancy. Despite the concerning endoscopic and imaging appearance, the absence of neoplastic cells prompted further investigation.

Serum IgG4 levels were elevated. Immunohistochemical staining of gastric biopsy specimens revealed more than 50 IgG4-positive plasma cells per high-power field, with an IgG4/IgG ratio greater than 40%.

Laparoscopic biopsy of perigastric lymph nodes showed dense fibrosis, lymphoplasmacytic infiltration, eosinophils, and obliterative vasculitis, which are findings consistent with IgG4-related disease.

Together, these findings established the diagnosis of gastric IgG4-related disease, with fungal elements interpreted as secondary colonization.

The patient was treated with oral prednisone (30 mg daily) and a proton pump inhibitor. Symptoms improved rapidly, and corticosteroids were tapered over 6 months.

Follow-up endoscopy demonstrated complete resolution of the ulcer. At 6 months after discontinuation of therapy, the patient remained in clinical remission.

Gastric IgG4-RD is a rare manifestation that can closely mimic gastric carcinoma. Repeated negative biopsies in a suspicious lesion should prompt reconsideration of the diagnosis, particularly when accompanied by eosinophilia or elevated immunoglobulin levels. Diagnosis relies on characteristic histopathology and IgG4 immunostaining, and corticosteroids remain highly effective first-line therapy.

Authors reported no conflicts of interest.