Aneurysm of the Communicating Vein Between the Left Renal Vein and Left Ascending Lumbar Vein Mimicking Retroperitoneal Lymphadenopathy: A Case Report

Introduction: Aneurysm of the communicating vein between the left renal vein and left ascending lumbar vein is extremely rare, with only anecdotal reported cases. Unless detected and recognized promptly, this rare condition may give rise to severe bleeding in patients undergoing retroperitoneal surgery. It may also closely mimic enlarged retroperitoneal lymph nodes, paragangliomas, adrenal masses, or renal artery aneurysms. Case Report: In this case study, we reported the imaging findings of this rare entity, which was falsely diagnosed as an enlarged retroperitoneal lymph node in an outside medical center, reported to be consistent with metastatic disease in a patient with newly diagnosed testicular cancer. Conclusion: The aneurysm of the communicating vein should be considered in the differential diagnosis in patients with testicular cancer and other disease processes where lymph nodes are commonly affected.