LEUKOCYTE BEHAVIOR IN A FREE-FLAP MODEL-FOLLOWING CHEMOTHERAPY AND APPLICATION OF GRANULOCYTE-COLONY-STIMULATING FACTOR (GCSF)

Free-flap reconstruction following tumor resection and chemotherapy is used increasingly in sarcoma patients. Granulocyte colony-stimulating factor (GCSF) is used to stimulate polymorphnuclear leukocytes (PMNs) . In this study we used a free-flap model to investigate PMN behavior after chemotherapy and GCSF stimulation. Eighteen Lewis rats were divi ded into three groups: (1) chemotherapy + vehicle; (2) chemotherapy GCSF; and (3) control. Group 1 received vinblastine; group 2 received vinblastine plus 300 mu g rhGCSF. Blood was drawn for total white cell and PMN counts for 9 days. Free-flap surgery was simulated by isolati ng the cremaster muscle on its pedicle and anastomosing the artery. Le ukocyte-endothelium interaction was assessed by observation of leukocy tes rolling and sticking. Leukocyte sequestration was measured by coun ting leukocytes in the lungs and the abdomen. We found that leukocyte rolling and sticking were significantly increased, while sequestration was decreased in the chemotherapy + GCSF group. We conclude that leuk ocytes-endothelium interaction after chemotherapy and GCSF administrat ion is increased in the microcirculation. This augments the risk of mi crovascular compromise and subsequent flap failure, as capillary flow may be altered. (C) 1998 Wiley-Liss, Inc.