Diffuse Large B-Cell Lymphoma Presenting as Aortic Aneurysm Rupture: A Case Report

We present a rare case of diffuse large B-cell lymphoma (DLBCL) mimicking an abdominal aortic aneurysm rupture. A 78-year-old male with prior endovascular aneurysm repair presented with abdominal pain, hypotension, and renal failure. Imaging revealed a periaortic mass concerning for aneurysm leak; however, PET/CT and biopsy confirmed DLBCL. This case underscores the diagnostic challenge posed by periaortic lymphoma masquerading as vascular emergencies. Clinicians should maintain a broad differential, as early recognition may avoid unnecessary surgery and enable appropriate oncologic management.