Use of procalcitonin for the differential diagnosis of fever in cancer patients: an observational study

Fever often occurs in cancer patients and the possibility of having a reliable marker for the differential etiological diagnosis is desirable. The aim of this study was to investigate the eligibility of the use of procalcitonin (PCT) in hemato-oncological patients for the differential diagnosis of fever. We prospectively enrolled 98 cancer patients and divided them into two groups: those with active disease and those with non-active disease. Procalcitonin was dosed at Time 0 (recruitment) and at the onset of fever. On enrollment, PCT values were 0.1 ng/mL in 83% patients with active disease, and lower than 0.5 ng/mL in 23%, which is usually considered not suggestive of bacterial infection. Four percent of patients had values over 0.5 ng/mL and these were mainly patients with neuroendocrine tumors or affiliates. On enrollment, there were also no statistically significant differences in PCT values between the two groups of patients. This showed that active cancer is unable by itself to change PCT levels. In the active disease group, 21 episodes of fever due to bacterial infection were registered, and in all of them an increase in PCT values was observed. This demonstrates the ability of PCT to detect an infection-induced fever in cancer patients. Procalcitonin concentrations are not significantly altered by active neoplastic disease. On the contrary, in the course of fever due to a bacterial infection, PCT values increase and can, therefore, be considered a useful tool in the differential diagnosis between infection-induced fever and drug-related or tumor associated-fever. Procalcitonin may be a useful marker of bacterial infection even in cancer patients.