The Importance Of Biopsy: A Primary Gastrointestinal Tract Lymphoma Diagnosis

Primary gastrointestinal (GI) tract lymphoma is a rare cause of recurrent GI bleeding, with the duodenum being the least common site of small bowel involvement. Lymphoma is often seen as polypoid lesions on endoscopy, but may present as an ulcer, often mistaken for other ulcerative conditions. We highlight a rare de novo presentation of diffuse large B-cell lymphoma (DLBCL) to emphasize the importance of prompt endoscopic evaluation and ulcer biopsy, which allows for earlier detection and treatment, leading to improved patient survival. An 86-year-old female with a past medical history of gastroesophageal reflux disease and Diffuse Large B-cell Lymphoma of the stomach initially diagnosed and treated 17 years prior, presented with abdominal pain, nausea, vomiting, hematochezia, and an unintentional weight loss of 10 pounds over the past month. Physical exam was remarkable for a grade II systolic murmur, but was otherwise normal. All blood work including white blood cell count, Hgb, and BUN/Cr were within normal limits. An abdominal Computed Tomography (CT) scan with contrast showed gastric antral and duodenal edematous wall thickening, consistent with gastritis and duodenitis. The patient underwent esophagogastroduodenoscopy (EGD) revealing a distal duodenal ulcer [Image 1]. Biopsy showed High Grade B-cell Lymphoma with a high proliferation index, morphologically consistent with DLBCL [Images 2,3]. The neoplastic lymphocytes were immunohistochemically positive for CD10, CD20, BCL2, BCL6 and, MUM1 confirming germinal center type DLBCL. Molecular studies ruled out double/triple hit lymphoma. The patient was discharged in stable condition following supportive care with outpatient referral to oncology for bone marrow biopsy and further management. Primary gastrointestinal lymphoma is rare, accounting for only 1-4% of all GI malignancies. Tissue biopsy is needed for microscopic analysis. However, current guidelines for ulcer biopsy versus expectant management are conflicting and require further study. Standard therapy for advanced DLBCL is 6 cycles of R-CHOP-21 (Rituximab, Cyclophosphamide, Doxorubicin, Vincristine, Prednisone), given every 21 days. Early diagnosis and treatment supports a favorable prognosis with average 5-year progression-free and overall survival rates greater than 60%. Albeit rare, clinicians must consider primary lymphoma in the differential diagnosis of GI bleed with ulcerative lesions to avoid delay in diagnosis and treatment.2526_A Figure 1. Distal duodenal ulcer via esophagogastroduodenoscopy (EGD).2526_B Figure 2. H&E stain at 40x magnification showing small bowel infiltration by diffuse lymphoid proliferation (asterisk) effacing normal duodenal architecture.2526_C Figure 3. Proliferation index of greater than 90% visualized by Ki-67 immunostain.