Predictive value of preoperative neutrophil-to-lymphocyte ratio in non-metastatic papillary renal cell carcinoma patients after receiving curative surgery.

Objective: To determine the predictive value of preoperative neutrophil-to-lymphocyte ratio (NLR) for disease-free survival (DFS) in non-metastatic papillary renal cell carcinoma (pRCC) patients following partial or radical nephrectomy.

Methods: We retrospectively analyzed 315 non-clear cell RCC patients who received curative surgery in our hospital from 2013 to 2018, from which 76 pRCC patients without metastasis (TNM) were selected. The receiver operating characteristics (ROC) curve was drawn and an NLR cut-off of 2.5 was set to achieve maximum diagnostic accuracy for predicting DFS. Kaplan-Meier method and the Cox regression model was used to determine the relationship of NLR with DFS.

Results: During a median follow-up of 28.0 months (IQR 15.9-42.1, mean 31.4), disease recurred in 12 patients (15.8%) recording a median duration of 14.4 months (IQR 8.6-22.9, mean 16.6). The 5-year DFS was 85.5% and 61.6% for the low (<2.5) and high (≥2.5) NLR groups respectively. According to Kaplan-Meier analysis, DFS was significantly lower in the high NLR group compared with that in the low NLR group (=0.03). Univariate analysis revealed that high NLR level (HR 3.3, =0.041), advanced pathological T stage (HR 10.1, <0.001), larger tumor size (HR 1.2, =0.008) and radical nephrectomy (HR 5.7, =0.025) were associated with poor DFS, while multivariate analysis indicated that only advanced pathological T stage (HR 6.9, =0.010) and high NLR level (HR 3.8, =0.028) remained as the independent prognostic factors for poor DFS.

Conclusion: A high preoperative NLR level was an independent prognostic marker for DFS in the patients of non-metastatic pRCC (pT1-3N0M0) following curative surgery. This can be used as an adjuvant tool to select patients for clinical trials or more frequent follow-up strategies.