Background: Cancer surgery is known to lead to a deterioration in host defence mechanisms and an increase in susceptibility to infection after operation. Filgrastim enhances important antimicrobial functions of neutrophils including chemotaxis, phagocytosis and oxidative killing mechanisms.
Methods: The effects of additional (all patients received perioperative 3 ' 25 mg kg-1 cefotiam and 1 ' 20 mg kg-1 metronidazole) preoperative prophylaxis with filgrastim (5 microg kg-1 12 h prior to surgery plus 5 microg kg-1 0 h prior to surgery) on neutrophil phagocytosis and reactive oxygen radical production and postoperative infections in 24 patients undergoing cancer neck dissection were studied. Phagocytic capacity was assessed by measuring the uptake of fluorescein isothiocyanate-labelled Escherichia coli and Staphylococcus aureus by flow cytometry. Reactive oxygen generation after phagocytosis was estimated by determining the amount of dihydrorhodamine 123 converted to rhodamine 123, intracellularly.
Results: In the filgrastim-treated patients a higher neutrophil phagocytic capacity was seen intraoperatively, and 1-5 days postoperative, but not prior to surgery. Reactive oxygen radical production was significantly higher in filgrastim-treated patients prior to surgery, intraoperative and postoperative (1-5 days). 2/12 (17%) patients had postoperative infections in the filgrastim group and 9/12 (75%) patients had infections in the placebo group (P < 0.001). In particular, wound infections were recorded more often in the placebo group (1/12 vs. 6/12; P = 0.004).
Conclusion: We conclude that filgrastim enhances perioperative neutrophil function and could be useful in the prophylaxis of postoperative wound infections in patients undergoing cancer neck dissection.