MPXI AND EARLY NEUTROPHILIA - NEW POTENTIAL THERAPEUTIC BIOMARKERS FOR RECOMBINANT HUMAN GRANULOCYTE-COLONY-STIMULATING FACTOR

We evaluated the effect of recombinant human granulocyte colony-stimul ating factor (rhG-CSF) given after myelosuppressive chemotherapy in 15 cancer patients. No severe neutropenia (absolute neutrophil count, AN C < 0.5 x 10(3)/mu L) was noticed in 10 rhG-CSF primary prophylactic p atients, but was noticed in two of five rhG-CSF secondary prophylactic patients. Neutrophilia characterized by shift to the left occurred wi thin 24 hours after starting rhG-CSF prophylaxis. Thereafter, conversi on to normal level occurred within 24 hours. The peak of neutrophilia occurred earlier in the primary group than in the secondary prophylact ic group. The detection of myeloperoxidase (MPO) using flow cytochemis try blood autoanalyzer (Technicon(R) H1) was evaluated as mean peroxi dase index (MPXI). Leukocyte alkaline phosphatase (LAP) using the meth od of Kaplow (Am J Clin Pathol39:439-449, 1963) was recorded as LAP sc ore. There was a statistically significant elevation of MPXI in the pr imary group over the secondary prophylactic patients. The LAP activity was in normal range. There was a slightly decreased red blood cell (R BC) count, hemoglobin (Hb), and platelet count. In conclusion, rhG-CSF induced neutrophilia with efficient enzymatic activity. These finding s demonstrate the value of rhG-CSF in patients receiving chemotherapy. MPXI and early neutrophilia may serve as a potential biomarker of the rapeutic efficacy of rhG-CSF. (C) 1998 Wiley-Liss, Inc.