Effects of gemcitabine on renal function in patients with non-small cell lung cancer

Gemcitabine is a novel fluorine-substituted cytarabine (Ara-C) analogue with activity against a range of solid tumours. Besides dose-limiting haematological toxicity, renal side-effects were observed from phase I and II studies concerning elevations of serum creatinine, proteinuria and erythrocyturia. The aim of this study was to investigate the effect of gemcitabine on renal function in 11 untreated patients with non-small cell lung cancer (NSCLC). Gemcitabine was given as weekly infusions of 1250 mg/m2 for 3 weeks, followed by 1 week rest. This comprised one cycle (maximum of six cycles). The glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) were measured simultaneously with a constant infusion of 125I-iothalamate and 131I-hippuran, respectively. Tubular damage was monitored by excretion of tubular enzymes (lactic dehydrogenase (LDH), alkaline phosphatase (ALP), gamma-glutamyltransferase (GT) and beta 2-microglobulin); glomerular damage was monitored by excretion of albumin in the urine. In 9 patients, the effect of the first infusion was evaluated. After the first infusion of gemcitabine, no change was observed in renal function. After two, three, and six cycles of treatment, no significant changes in GFR and ERPF were noticed in 9 evaluable patients. However, in 3 patients, a decrease in GFR of > 10% was observed after multiple cycles. In one of them this was accompanied with albuminuria (360 mg/24 h) and erythrocyturia. There were no significant changes in urinary excretion of tubular enzymes or albumin. In conclusion, we did not observe acute renal toxicity with gemcitabine. No significant cumulative effects of gemcitabine on renal function could be detected, although 3 patients, treated with multiple cycles of gemcitabine, showed a moderate decrease in renal function. Glomerular damage might play a role in the development of renal function loss.