The authors propose that high neutrophil-to-lymphocyte ratio (NLR) is associated with poor disease-free survival (DFS) in patients with human papillomavirus positive (HPV+) oropharyngeal cancer (OPC). This is a retrospective study that compared the outcomes of 43 patients treated for HPV+ OPC with high NLR to 61 patients treated for HPV+ OPC with low NLR. Patients had been treated at Samsung Medical Center, Seoul, for HPV+ OPC between November 2004 and December 2016. Patients with immunocompromise, immunomodulatory treatment or haematogenous pathologies were excluded. Sixty-six patients were treated with concurrent chemoradiation (CCRT), three with definitive radiotherapy (RT) alone, and 35 with surgery followed by adjuvant RT. NLR was calculated based on laboratory data obtained within four weeks preinitiation of treatment. The optimal cutoff value of 2.42 (sensitivity 78.4%, specificity 64.7%) determining high (>2.42) and low (<2.42) NLR was determined using receiver operating characteristic curve analysis. The follow-up period ranged from 6-120 months.
Locoregional failure rate was 4.9% (3/61) in the patients with low NLR and 11.6% (5/43) in patients with high NLR. All four distant metastases occurred in patients with high NLR. The five-year DFS rate was significantly lower in the patients with high NLR compared to those with low NLR (68.1% vs 94.7%, log rank P=0.01).
Although there was lower five-year overall survival in the high NLR group compared to the low NLR group, it was not statistically significant (85.3% vs 96.3%, P=0.09). Their analysis also found that when used as a continuous variable, NLR maintained a significant impact on DFS (HR, 1.11; 95% CI, 1.01-1.22; P=0.03), but not on OS (HR, 1.06; 95% CI 0.92-1.23; P=0.39). When a different cutoff of four, as proposed in a recent meta-analysis, was used, high NLR was significantly associated with both worse OS and DFS (P=0.022 and P=0.043 respectively). The limitations include a retrospective analysis at a single institution with substantial heterogeneity in treatment modality and cancer staging, while the prognostic value of NLR needs to be validated in a separate set of patients with HPV+ OPC.
