Identifying distinct risks of treatment failure in nasopharyngeal carcinoma: Study based on the dynamic changes in peripheral blood lymphocytes, monocytes, N classification, and plasma Epstein‐Barr virus DNA

Abstract Background To evaluate the prognostic value of the dynamic change in absolute lymphocyte counts (ALCs) and absolute monocyte counts (AMCs) and identify patients with N stage and plasma Epstein‐Barr virus (EBV) DNA levels in nasopharyngeal carcinoma (NPC) who are at risk of treatment failure. Methods A total of 1124 eligible patients with Stage II–IVb NPC treated with concurrent chemoradiotherapy (CCRT) were enrolled. Percentage changes in the ALC (ΔALC%) and AMC (ΔAMC%) were calculated. Results Patients with high ΔALC% were correlated with poorer 5‐year overall survival (OS), progression‐free survival (PFS), and distant metastasis‐free survival (DMFS) rates than those with low ΔALC%. Likewise, high ΔAMC% was significantly associated with worse outcome than low ΔAMC% (OS, p = 0.001; PFS, p = 0.001; DMFS, p = 0.034). Multivariate analyses revealed that ΔALC% ( p = 0.046), ΔAMC% ( p = 0.019), and EBV DNA level ( p < 0.001) were independent prognostic factors for OS. With respect to PFS, ΔALC% ( p = 0.036), ΔAMC% ( p = 0.011), N classification ( p = 0.016), and EBV DNA level ( p < 0.001) were also independent prognosticators. Based on the aforementioned independent risk factors (ΔALC% ≥ 83.33%, ΔAMC% ≥ 40.00%, Stage N2–3, EBV DNA ≥ 4000 copies/ml), patients were divided into three different risk groups (low‐risk group [with <1 risk factor], intermediate risk group [with 1–3 risk factors], and high‐risk group [with 4 risk factors]) that correlated with disparate risks of death ( p < 0.001), disease progression ( p < 0.001), and distant metastasis ( p < 0.001). Conclusions High ΔALC% and ΔAMC% were correlated with poor prognosis in patients with NPC. Risk stratification based on ΔALC%, ΔAMC%, N classification, and plasma EBV DNA levels could provide potential utility for risk‐adapted therapeutic strategies for NPC.