Predictive value of preoperative monocyte-lymphocyte ratio among patients with localized clear renal cell carcinoma of ≤7 cm on preoperative imaging

Abstract

We investigated the prognostic ability of preoperative monocyte-lymphocyte ratio for oncologic outcomes in non-metastatic clear cell renal cell carcinoma of ≤7 cm on preoperative computed tomography (CT).We retrospectively reviewed 1637 patients who underwent radical or partial nephrectomy for solid renal masses ≤7 cm (2005-2014). We included 1137 patients after exclusion of benign pathology, non-clear cell, morbidity affecting inflammatory markers, metastasis, regional lymphadenopathy, positive margin, and follow up <12 months. According to cutoff values of 0.21, we had high ≥0.21 and low <0.21 preoperative monocyte-lymphocyte ratio groups. Mann-Whitney U and chi-squared tests were used for continuous and Dichotomous variables. Univariate and multivariate Cox regression analysis were used to predict factors affecting recurrence and survival. Kaplan-Meier curve was used for survival analysis.At a median age of 56 years with a median follow up of 65 months, 51 patients had a recurrence (4.5%). There were no statistical differences between the high and low monocyte-lymphocyte ratio groups as regard the pathological characters (P > .005). Monocyte-lymphocyte ratio was a predictor for recurrence-free and cancer-specific survivals (hazard risk [HR] 2.17, P = .012 and HR 4.06, P = .004, respectively). A higher monocyte-lymphocyte ratio was significantly associated with worse, both 10-year recurrence-free (90.2% vs 94.9%) and cancer-specific survival (89.5% vs 98.8%) (Log-rank, P = .002 and P < .001, respectively).The preoperative monocyte-lymphocyte ratio is an independent prognostic marker for recurrence-free and cancer-specific survivals after curative surgery for non-metastatic clear cell renal cell carcinoma of ≤7 cm on preoperative CT.

Figure 1

A flow chart showing the algorithm of database selection after application of inclusion and exclusion criteria. MLR = monocyte–lymphocyte ratio.

Figure 2

Optimal cutoff levels for MLR were applied at 0.21 using receiver operating curve. (A) Considering recurrence-free survival as a state variable. (B) Considering cancer-specific survival as a state variable. AUC = area under the curve, MLR = monocyte–lymphocyte ratio.

Figure 3

Kaplan–Meier curves according to preoperative MLR. (A) Recurrence-free survival. (B) Cancer-specific survival. MLR = monocyte–lymphocyte ratio.