Endonephrology: Evolving Techniques of Endoscopic Ultrasound in Diagnosing Renal Lymphoma

Mucosa-associated lymphoid tissue lymphoma is a subtype of non-Hodgkin lymphoma, exceedingly rare when originating in the kidney. Most renal masses are percutaneously sampled with ultrasound or computed tomography guidance; however, limitations can include location, size, and body habitus, which may be resolved using endoscopic ultrasound-guided approaches. We present an unusual case of a 77-year-old man with history of systemic lupus erythematosus, duodenal mucosa-associated lymphoid tissue lymphoma in remission, and rectal adenocarcinoma who presented for evaluation of a right renal mass, which highlights the novelty of endoscopic ultrasound-guided renal evaluation and tissue acquisition.