Large renal artery aneurysm masquerading as renal cell carcinoma

Renal artery aneurysms (RAAs) are rare. Diagnosis is typically incidental with most cases asymptomatic and detected on routine imaging. Rarely large saccular RAAs may appear to extend to the neighbouring renal parenchyma. Differentiating these from renal tumours can be difficult and subsequent investigation with biopsy may result in fatal rupture. Our case describes an RAA arising from the right renal artery masquerading as renal cell carcinoma (RCC). Emphasis is placed upon thorough radiological evaluation ensuring that RAA is considered and excluded from the differential diagnosis prior to biopsy or surgical intervention. The role of multidisciplinary input is also emphasised.