[Relationship between plasma and urinary platinum pharmacokinetics with cisplatin nephrotoxicity in breast cancer patients].

In 25 cycles of 20 breast cancer patients who received 26 cycles of high-dose cisplatin (100 mg/m2, iv drip), the urinary Alb, IgG and NAG values were elevated above normal. These patients were divided into low-nephrotoxicity and high-nephrotoxicity groups by the degree of renal dysfunction. Of these patients 35% showed high-nephrotoxicity. They had significantly higher plasma and/or urinary Pt peak levels during cisplatin infusion than did those with low-nephrotoxicity. And 70-80% of the patients developed significant nephrotoxicity when the urinary Pt level rose up to greater than 40 micrograms/ml or plasma Pt level greater than 4 micrograms/ml. It is very important to keep the urinary and plasma Pt level below 40 micrograms/ml and 4 micrograms/ml respectively in order to reduce the nephrotoxicity. It is suggested that the urine output be maintained over 300 ml/hr for 2 hours before and after the completion of infusion and greater than 100 ml/hr in the following 3 days. This helps keep the cisplatin-induced nephrotoxicity in less severe and the function of kidney easy to recover.