Procalcitonin and C-Reactive Protein/Procalcitonin Ratio for Distinguishing between Infectious and Neoplastic Fever in Cancer Patients

Objective center dot This study aims to investigate the potential of procalcitonin (PCT) levels and the C-reactive protein/ procalcitonin ( CRP/PCT) ratio as markers for distinguishing between infectious and neoplastic fever among febrile patients with malignant tumors. Methods center dot A retrospective analysis was conducted on febrile patients admitted to the hospital with malignant tumors. The patients were categorized into an infection group (67 cases) and a non-infection group (73 cases) based on the presence or absence of positive cultures. PCT levels, CRP levels, and CRP/PCT ratios were compared between the two groups. The receiver operating characteristic curve (ROC) was used to identify optimal cut-off values. Results center dot Data from 140 patients between January 2017 and December 2021 were extracted for analysis. Patients in the infected group showed elevated PCT levels and significantly decreased CRP/PCT ratios compared to the non-infected group (P <.01). The calculated cut-off values for distinguishing infectious and neoplastic fever were 0.52 ng/mL for PCT and 101.80 for CRP/PCT ratio. The ROC curve results revealed good sensitivity for both PCT (74.63%) and CRP/PCT (70.15%), while CRP/PCT demonstrated higher specificity (78.08%) compared to PCT (58.90%). Conclusions center dot PCT and CRP/PCT are both sensitive markers for identifying infection in patients with malignant tumors, with PCT showing slightly better sensitivity but lower specificity than CRP/PCT. Our findings suggest that CRP/PCT may be more valuable than PCT in distinguishing between infectious fever and neoplastic fever in cancer patients.