Validation of the ^CSRFENCE score for prediction of febrile neutropenia during chemotherapy cycles 2-6

Purpose: Though febrile neutropenia (FN) risk prediction models are important in clinical practice, their external validation is limited. In this study, we validated the Cycle-Specific Risk of FEbrile Neutropenia after ChEmotherapy (^CSRFENCE) score for predicting FN.

Methods: We reviewed the medical records of patients with solid malignancies and diffuse large B-cell lymphoma during chemotherapy cycles 2-6 and recorded if patients developed FN, defined as absolute neutrophil counts less than 500 cells/microL with fever more than or equal to 38.2 ℃. The ^CSRFENCE score was determined by adding the risk factors' coefficients described by the original study; subsequently, the score was used to classify chemotherapy cycles into the following risk groups for developing FN: low, intermediate, high, and very high risk. The discriminatory ability of the score was assessed using area under the receiver operating characteristics curve (AUROCC) and incidence rate ratios (IRR) within each ^CSRFENCE risk group.

Results: We analyzed 2870 chemotherapy cycles, of which 42 (1.5%) were associated with FN. Among those, 3 (7.1%), 14 (33.3%), 5 (12%), and 20 (47.6%) were classified as low, intermediate, high, and very high risk for developing FN, respectively. The AUROCC was 0.72 (95% CI 0.64-0.81). Compared with the low risk group (n = 666), the IRR of developing FN was 1.01 (95% CI 0.15-43.37), 0.69 (95% CI 0.08-32.46) and 1.17 (95% CI 0.17-49.49) in the intermediate (n = 1431), high (n = 498) and very high (n = 275) risk groups, respectively.

Conclusion: The ^CSRFENCE model can moderately stratify patients into four risk groups for predicting FN prior to chemotherapy cycles 2-6.