Purpose: Magnesium supplementation is an effective protective method against cisplatin-induced nephrotoxicity (CIN); however, there are few reports regarding the mechanism of its nephroprotective effect. The aim of this study was to determine whether premedication with intravenous magnesium prevents CIN and to determine the relationship between its nephroprotective effect and serum magnesium level.
Methods: Fifty-eight patients with head and neck cancer who received cisplatin, docetaxel, and 5-fluorouracil (DCF) were retrospectively investigated. Grade 2 or more serum creatinine elevation was defined as CIN. The incidence of CIN was compared between a magnesium sulfate (20 mEq, 2.46 g) premedication group and a non-magnesium group during the first cycle and in all cycles.
Results: CIN did not occur in any patients receiving magnesium premedication but did occur in 5 of 29 patients during the first cycle and in 6 patients during all subsequent cycles in patients who did not receive magnesium premedication. Furthermore, the variation of creatinine clearance was significantly worse in the non-magnesium group than in the magnesium premedication group from baseline. There was no difference in adverse effects or response rate between the two groups. Univariate analysis suggested that magnesium premedication significantly reduced the risk of CIN. On the other hand, serum magnesium depletion was seen in both groups to equal degrees despite supplementation.
Conclusion: Intravenous magnesium premedication has a protective effect on cisplatin-induced nephrotoxicity without the influence on the serum magnesium level. Magnesium premedication is a simple nephroprotective method that does not influence other adverse effects or rate of response to chemotherapy.
Keywords: Cisplatin; Hypomagnesemia; Magnesium; Nephrotoxicity; Prevention.