Predictive Parameters of Febrile Neutropenia and Clinical Significance of G-CSF Receptor Signaling Pathway in the Development of Neutropenia during R-CHOP Chemotherapy with Prophylactic Pegfilgrastim in Patients with Diffuse Large B-Cell Lymphoma

PURPOSE: Pegfilgrastim is widely used to prevent chemotherapy-induced neutropenia (CIN) and febrile neutropenia (FN) in patients with diffuse large B-cell lymphoma (DLBCL). We investigated the predictive factors affecting CIN and FN incidence in patients with DLBCL receiving rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) chemotherapy with pegfilgrastim and conducted experiments to find reason for the occurrence of CIN even when pegfilgrastim was used. MATERIALS AND METHODS: We reviewed the CIN and FN events of 200 patients with DLBCL. Based on these data, we investigate the association with predictive factor and the levels of granulocyte-colony stimulating factor (G-CSF) receptor signaling pathway markers (pSTAT3, pAKT, pERK1/2, pBAD, and CXCR4) in bone marrow (BM) samples isolated from patients with DLBCL. RESULTS: FN was significantly associated with stage III/IV (hazard ratio [HR], 12.74) and low serum albumin levels (HR, 3.87). Additionally, patients with FN had lower progression-free survival (PFS; 2-year PFS, 51.1 % vs. 74.0%) and overall survival (OS; 2-year OS, 58.2% vs. 85.0%) compared to those without FN. The occurrence of CIN was associated with overexpression of G-CSF receptor signaling pathway markers, and expression levels of these markers were upregulated in BM cells co-cultured with DLBCL cells. The rate of neutrophil apoptosis was also higher in neutrophils co-cultured with DLBCL cells and was further promoted by treatment with doxorubicin. CONCLUSION: Our findings suggest that high DLBCL burden may alter the BM environment and G-CSF receptor signaling pathway, even in chemotherapy-naïve state, which may increase CIN frequency during R-CHOP chemotherapy.