Although liver enzyme function (AST, ALT and γ-GTP) was significantly different in patients with and without G4 neutropenia (P<0.1) in the univariate analysis, these factors were not used as explanatory variables in the logistic regression analysis, as all patients developing G4 neutropenia demonstrated values of these parameters that were within the normal range. This evidence concerns the gene GPT and Decreased total neutrophil count.