S3421 A Rare Case of Biliary Obstruction Caused by Diffuse Large B-Cell Lymphoma

Introduction: Biliary obstruction is most commonly caused by gallstones, strictures, pancreatic or biliary malignancies. Invasion by lymphoma is rare. In 1 study, lymphoma accounted for only 0.6% of cases of biliary obstruction. Diffuse large B-cell lymphoma (DLBCL) is the main subtype of Non-Hodgkin lymphoma (NHL). The gastrointestinal (GI) tract is the primary site of extranodal NHL, and is often linked to a poor prognosis. We present a case of biliary obstruction caused by biopsy-confirmed high-grade DLBCL. Case Description/Methods: A 55-year-old man with no past medical history presented with jaundice, melena, fever and weight loss over 3 weeks. On arrival, he was tachycardic and labs showed transaminitis with direct hyperbilirubinemia, anemia, and elevated INR. Computed tomography of the abdomen and pelvis found a 17 cm mass/due to the melena, Gastroenterology recommended esophagogastroduodenoscopy (EGD) to evaluate for tumor bleeding and diagnostic biopsies. He was started on a proton pump inhibitor (PPI) twice daily. EGD showed an invasive gastric mass. The biopsies showed advanced DLBCL confirmed by chromosomal studies. Due to hepatic insufficiency, biliary decompression was recommended but a target was not found for percutaneous drainage. Gastroenterology planned to relieve the obstruction with stenting via endoscopic retrograde cholangiopancreatography (ERCP). An abdominal magnetic resonance imaging was performed to delineate the anatomy and showed extensive infiltration and obstruction of multiple bile ducts. ERCP was deferred due to high perforation risk. Oncology postponed standard chemotherapy due to hepatically metabolized agents. Steroids and cycle 1 of Rituxan were started followed by a non-traditional regimen of gemcitabine and oxaliplatin. He tolerated chemotherapy and was discharged with Oncology follow-up. On discharge, melena had resolved, and plan was to continue PPI twice daily. Discussion: GI DLBCL can present with abdominal pain, B-symptoms, and mild bleeding due to its ulcerative features. Severe symptoms like obstruction, perforation, or profuse bleeding signify advanced disease. PPIs protect the gastric mucosa to prevent significant bleeding. Endoscopy is diagnostic but often delayed until severe symptoms present, limiting treatment and interventions. Timely symptom recognition prompts diagnostics, like EGD and endoscopic ultrasound, to facilitate early disease detection. ERCP interventions can then be pursued with fewer complication risks, enhancing subsequent chemotherapy efficacy.