Lithium-treated patients are at increased risk of renal tumors, according to French researchers.
In a retrospective study of 170 lithium-treated patients, renal tumors developed in 14 (8.2%) over a 16-year period. These tumors included 7 malignant and 7 benign tumors. The mean duration of lithium exposure at diagnosis was 21.4 years. The cancers included 3 clear-cell and 2 papillary renal cell carcinomas, 1 hybrid tumor with chromophobe and oncocytoma characteristics, and 1 clear-cell carcinoma with leiomyomatous stroma. The benign tumors included 4 oncocytomas, 1 mixed epithelial and stromal tumor, and 2 angiomyolipomas.
Lithium-treated patients had an incidence of renal tumors 7.5 times greater than that of the general French population, researchers reported in Kidney International (2014;86:184-190). Additionally, the researchers compared lithium-treated patients with chronic kidney disease (CKD) and a group of lithium-free CKD patients matched for age, sex, and estimated glomerular filtration rate. The frequency of renal cancer and oncocytoma was significantly higher in the lithium-treated group (4.1% vs. 0.3% and 2.4% vs. 0%, respectively).