Background: Lithium salts are widely used in the treatment of affective disorders of the bipolar type. Lithium is a nephrotoxic substance which can cause both acute and chronic renal disease, including cyst formation. Cysts appear to predispose the kidney to renal cell carcinoma.
Case Report: A case of renal cell carcinoma in a background of acquired cystic disease due to chronic lithium toxicity is described.
Conclusions: Kidneys with multiple cysts are at risk of renal cell carcinoma. Although it is difficult to determine if long term Lithium use renal cell carcinoma, patients leads to the development of on long-term lithium therapy should undergo regular renal function and imaging tests.

Keywords: Carcinoma, Renal Cell, renal cysts, Anti-Inflammatory Agents, Non-Steroidal, Lithium Chloride, Kidney Neoplasms