Bianca Thakkar, DO1, Rukmoni Balasubramanian, MBBS2, Minh Thu T.. Nguyen, MD3, Krzysztof Glomski, MD, PhD4, Marianna Scranton, DO4 1University of Connecticut Health, Farmington, CT; 2University of Connecticut Health, Hartford, CT; 3University of Connecticut, Farmington, CT; 4Hartford HealthCare, Hartford, CT Introduction: Primary gastric diffuse large B-cell lymphoma (PG-DLBCL) is an aggressive and uncommon subtype of extranodal non-Hodgkin lymphoma (NHL), accounting for 5% of all gastric malignancies. It is most commonly seen in males aged 50–60 and often presents with nonspecific gastrointestinal symptoms. While Helicobacter pylori infection is implicated in the pathogenesis of mucosa-associated lymphoid tissue (MALT) lymphoma, its association with PG-DLBCL is less clearly established.
Case Description/
Methods: We report the case of a 64-year-old Vietnamese male who presented with progressive dysphagia. Although esophagogastroduodenoscopy (EGD) was recommended, the patient was lost to follow-up. He later re-presented with hematemesis, epigastric pain, and weight loss. Multiple EGDs identified a large antral gastric ulcer that repeatedly tested negative for malignancy but was positive for H. pylori. Eventually, endoscopic ultrasound (EUS) with fine needle biopsy confirmed PG-DLBCL, staged as T3 N1. Notably, the patient was nonadherent to H. pylori eradication therapy, and his course was marked by delays in diagnosis due to social determinants of health, including housing instability. The patient is currently undergoing R-CHOP chemotherapy. His course was further complicated by gastric outlet obstruction secondary to the cancer, status post EUS-guided gastrojejunostomy with Axios stent placement. Discussion: This case underscores the diagnostic challenges associated with PG-DLBCL. The disease often mimics benign gastric pathology, leading to diagnostic delays. Repeat EGDs with biopsy and EUS are critical when clinical suspicion for malignancy remains high despite initial negative findings. Diagnosis of PG-DLBCL requires histologic confirmation of large atypical B-cells, supported by immunohistochemical markers such as CD20. Staging typically follows the Lugano classification and involves imaging modalities such as PET-CT. Standard treatment consists of R-CHOP chemotherapy, which is associated with favorable outcomes in limited-stage disease. Prognostic factors include the International Prognostic Index (IPI) score and response to initial therapy.
Figure: Figure 1. Imaging Studies A. CT of the abdomen and pelvis demonstrating circumferential thickening of the esophagus (yellow arrow). B. EGD showed a non-obstructing, non-bleeding gastric ulcer without evidence of perforation. C. EUS demonstrating a cratered gastric ulcer in the antrum, involving three-quarters of the lumen. Mucosal bridges over the ulcer gave the appearance of multiple ulcers.
Figure: Figure 2. On routine hematoxylin and eosin (H&E)-stained tissue sections, biopsy fragments demonstrated diffuse involvement by a mononuclear cellular infiltrate composed of large epithelioid cells with round to folded, irregular nuclei, variably prominent nucleoli, and moderate pale cytoplasm (A). Immunohistochemical test showed that the neoplastic cells were strongly and diffusely positive for CD20 (B), and multifocally positive for BCL6 and MUM1 (C, D), while negative for CD10 and CD3 (not shown). The Ki-67 proliferation index was approximately 70-80% (not shown). Fluorescent in situ hybridization (FISH) testing for MYC, BCL2, and BCL6 revealed no rearrangements. The morphologic, immunohistochemical, and cytogenetic findings supported a diagnosis of diffuse large B-cell lymphoma (DLBCL), NOS (non-GCB subtype by Hans Algorithm).
Disclosures: Bianca Thakkar indicated no relevant financial relationships. Rukmoni Balasubramanian indicated no relevant financial relationships. Minh Thu Nguyen indicated no relevant financial relationships. Krzysztof Glomski indicated no relevant financial relationships. Marianna Scranton indicated no relevant financial relationships.
Bianca Thakkar, DO1, Rukmoni Balasubramanian, MBBS2, Minh Thu T.. Nguyen, MD3, Krzysztof Glomski, MD, PhD4, Marianna Scranton, DO4. P2098 - Unmasking Primary Gastric Diffuse Large B-Cell Lymphoma (DLBCL), ACG 2025 Annual Scientific Meeting Abstracts. Phoenix, AZ: American College of Gastroenterology.
