Prognostic value of neutrophil-to-lymphocyte ratio in nasopharyngeal carcinoma: a systematic review and meta-analysis of 30 cohorts through June 30, 2026.

Abstract

Background: Previous meta-analyses have linked an elevated pretreatment neutrophil-to-lymphocyte ratio (NLR) to poor outcomes in nasopharyngeal carcinoma (NPC), but they included few recent cohorts and often combined adjusted and unadjusted estimates. We updated the evidence base and evaluated the consistency and certainty of the associations between pretreatment NLR and survival outcomes.

Methods: We systematically searched PubMed, Web of Science, Embase, the Cochrane Library, China National Knowledge Infrastructure (CNKI), and Wanfang Data from inception through June 30, 2026. Eligible reports were cohort studies of pathologically confirmed NPC that compared high versus low pretreatment NLR and reported multivariable-adjusted hazard ratios (HRs) for overall survival (OS), progression-free survival (PFS), distant metastasis-free survival (DMFS), or locoregional recurrence-free survival (LRFS). Two reviewers independently selected studies, extracted data, and assessed risk of bias using the Newcastle-Ottawa Scale (NOS). Random-effects models, prespecified subgroup analyses, leave-one-out analyses, assessment of small-study effects, and Grading of Recommendations Assessment, Development and Evaluation (GRADE) certainty assessment were used.

Results: Thirty cohorts comprising 11,671 patients were included; NOS scores ranged from 7 to 9. Elevated pretreatment NLR was associated with inferior OS [27 cohorts; HR: 2.16, 95% confidence interval (CI): 1.76-2.66] and PFS (18 cohorts; HR: 1.70, 95% CI: 1.45-2.00). Furthermore, high NLR correlated with compromised DMFS (6 cohorts; HR: 1.61, 95% CI: 1.33-1.93) and LRFS (2 cohorts; HR: 4.82, 95% CI: 1.51-15.31). Heterogeneity was substantial for OS (I²=84%) and moderate for PFS (I²=57%). Egger's tests indicated funnel-plot asymmetry for OS (P<0.001), but not PFS (P=0.26). GRADE certainty was very low for OS and PFS and low for DMFS and LRFS.

Conclusions: Elevated pretreatment NLR was associated with poorer survival outcomes in NPC. However, substantial heterogeneity, evidence of small-study effects for OS, and low to very low certainty of evidence preclude routine clinical implementation. Prospective validation using standardized sampling and cutoff methods is needed.