Clinicians are searching for a marker which may add to exclusion or diagnosis of relevant infection underlying neutropenic fever. The rise of such a parameter should ideally precede the date of significant microbiologic findings or justify additional intensive search for a focus of infection even in patients without pyrexia. However, the literature concerning the significance of CRP, proinflammatory cytokines and soluble adhesion molecules in the clinical evaluation of neutropenic fever is surprisingly small. In the case of procalcitonin, available data look very preliminary. Furthermore, in case of CRP, it appears that the widespread view that its determination may add substantially to the clinical evaluation of neutropenic fever is not well founded by most clinical trials listed here. Most of the studies available demonstrate several limitations such as poor design and small size of the study population. Additionally, studies were heterogeneous with respect to patients recruited (children and adults, patients with leukemia and patients with solid tumors) and compared different categories of febrile episodes. None of the investigators analyzed cost-effectiveness or impact of serial measurements of these parameters on patients' outcome. To our knowledge no single multicenter trial has been published addressing this issue. Although the group of proinflammatory cytokines and known acute-phase reactants will surely grow, more data on relevance of the available parameters in the diagnosis of neutropenic fever are needed.