Twenty-six patients with a malignancy who were receiving intermittent cytotoxic chemotherapy acquired putative bacterial infections while neutropenic. Fourteen patients with neutrophil counts less than 100 X 10(6)/L received cefuroxime plus amikacin. Twelve patients with neutrophil counts between 100 and 500 X 10(6)/L were given cefuroxime alone. The dosages were amikacin, 500 mg BID, and cefuroxime, 1.5 gm TID, although the dose of cefuroxime was halved in three patients because of low body weight and in one patient because of impaired renal function. Bacteriological proof of infection was obtained in 14 patients. In all but two, the bacteria were eradicated by therapy; those two had strains resistant to cefuroxime. Clinical cure was obtained in 15 patients (58%); marked improvement, in seven (27%). One of the patients not cured was probably not infected. In another, the organism was eradicated but the patient did not recover from preexisting shock and renal failure. There were minimal side effects. One patient had diarrhea, one complained of pain on injection, and two had slight increases in transaminase levels. Of particular note is the lack of renal toxicity, particularly in the five patients previously treated with cisplatin.