A 67-year-old male diagnosed with a 9-year history of ulcer, who currently presented with gastric ulcers and melenas.
Gastroscopy showed a large submucosal tumor in the posterior aspect of the lesser curvature of the stomach, with a deep ulceration of 2 cm, suggesting a differential endoscopic diagnosis with leiomyoma or ulcerated GIST.
At CT (CT) and endoscopic ultrasound, the mass was 40 x 36 mm thick plus celiac lymphadenopathy grade 1 cm. A PET-CT scan revealed absence of uptake in the mass due to celiac disease.
Biopsies of both the mass and lymph nodes were insufficient for histological diagnosis.
She had no history of Helicobacter pylori infection or chronic systemic inflammatory disorder.
The patient underwent surgery, obtaining a blocked piece that included partial gastrectomy of the body and pancreatectomy corporeal.
Macroscopic examination of the resection specimen showed a cavitated ulcer in the gastric wall of 4 cm wide, with raised edges and thickened walls with fibrous appearance.
The ulcerous bed appeared covered by helium material and remnants of fibrin, resting the lesion on the piece of partial pancreatectomy.
Microscopically, a gastric ulcer, deep, cavitated, with granulation tissue, recent hemorrhage and fibrin was confirmed.
Regarding the ulcer, marked hypocellular fibrosis was observed, affecting all layers of the gastric wall, especially in the submucosa and gastric serosa.
Isolated nodular lymphoid aggregates, some with germinal center, as well as lymphoplasmacytic inflammatory infiltrate fibrosis, with some isolated eosinophilic, were identified in the sinus of the disease.
Small veins of the gastric wall with luminal occlusion and occasional presence of plasma cells in its wall were also observed.
These histological findings suggested the diagnosis of inflammatory disease related to G4, so immunohistochemical studies were performed which confirmed the positivity of plasma cells for IgG4, immunoglobulin positive accumulation with more than 50 cells.
The balance of IgG4 positive cells with respect to total IgG positive cells was above 40%.
In addition, in some of the isolated lymph nodes, IgG4 positivity was also observed in both parenchymal and paracortex cells.
The deep ulcer, which was in contact with the pancreas, also showed a mild lymphoplasmacytic inflammatory infiltrate positive for IgG4, with distortion of large pancreatic ducts and endocrine hyperplasia of the exocrine parenchyma.
Some arteries also showed marked intimal fibrosis that caused luminal obstruction without associated inflammation.
In this patient, immunoglobulin G4 levels were not elevated at the time of diagnosis.
