Acute renal failure associated with the use of intraperitoneal carboplatin: a report of two cases and review of the literature. Carboplatin, a new analogue of cisplatin used in the treatment of ovarian carcinoma, has been demonstrated to be less nephrotoxic than its predecessor. To date, hundreds of cycles of therapy have been given without a significant incidence of renal failure. We report herein two cases of acute, nonoliguric renal failure in patients receiving intraperitoneal (IP) carboplatin as chemotherapy for advanced ovarian carcinoma. Each patient had received extensive previous treatment with cisplatin. The baseline serum creatinine levels in the patients were 0.9 and 1.1 mg/dL, respectively. After four cycles of IP carboplatin in Patient 1 and five cycles of IP carboplatin in Patient 2, the serum creatinine levels abruptly rose to 9.0 and 9.5 mg/dL, respectively, within a week after administration of therapy. No other primary etiologies for acute renal failure could be identified in either patient. One patient required hemodialysis briefly. Renal biopsy specimens were obtained from both patients. Patient 1 had focal and moderate interstitial nephritis with mild periglomerular fibrosis. Patient 2 had an edematous interstitium with a diffuse mononuclear cell infiltrate, focal interstitial hemorrhage, and toxic changes in proximal and distal tubules on electron microscopy. Treatment with oral prednisone at 1 mg/kg/day with a rapid taper over 4 weeks was done in both cases with the serum creatinine levels eventually dropping to 4.6 and 2.0 mg/dL, respectively. Acute interstitial nephritis and renal failure to this extent have not been previously reported with carboplatin therapy. The literature regarding carboplatin is reviewed with respect to the pathophysiology of its nephrotoxicity. 