Abstract
OBJECTIVE: To investigate the relationship between absolute neutrophils count (ANC) in different periods of treatment and the outcomes of patients and assess effect of longitudinal neutrophils variation during radiotherapy (RT) on prognosis in patients with nasopharyngeal carcinoma (NPC). METHODS: A total of 1753 patients with newly diagnosed NPC were retrospectively analyzed. Complete blood counts of patients were obtained before treatment, before, during, and end of RT. The survival rate was calculated by Kaplan-Meier method and the result was compared by the log-rank test. The univariate and multivariate COX regression analyses were performed to investigate the association between the variation of ANC and survival for patients in different periods. RESULTS: Higher ANC pretreatment (>4 × 10(9)/L) and pre-RT (>7 × 10(9)/L) were correlated with poor OS (89.7% vs 85.6%, P = .009; 88.3% vs 77.3%, P = .002, respectively). An increase >5 × 10(9)/L of ANC during RT was associated with adverse OS (87.9% vs 73.6%, P = .042). The multivariate Cox regression analysis showed that high ANC of pre-RT (>7 × 10(9)/L) and a high increase (>5 × 10(9)/L) of ANC during RT were independent prognostic factors of patients with NPC (P = .002, .044, respectively). CONCLUSION: Our results demonstrated that ANC was an independent prognostic factor for survival in patients with NPC who received RT. Neutrophils may promote tumor resistance to radiotherapy in NPC. LEVEL OF EVIDENCE: 2a.