Neutrophil-lymphocyte ratio evaluation in patients undergoing radical cystectomy

Abstract

To the Editor We have read with great interest the published article by Potretzke et al. [1] titled “NLR is predictive of upstaging at the time of radical cystectomy for patients with urothelial carcinoma of the bladder.” The authors have suggested that the preoperative neutrophil-lymphocyte ratio (NLR) was a cost-effective test that might be useful to predict pathologic upstaging in patients undergoing radical cystectomy. However, we think that some more points should be discussed. The NLR is an easily calculable laboratory marker used to evaluate systemic inflammation. It was shown that thyroid disorders, inflammatory bowel disease, essential hypertension, diabetes mellitus, cardiovascular events, renal or hepatic failure or both, obesity, metabolic syndrome, and many inflammatory diseases may potentially affect the NLR [2–4]. Therefore, it would be more appropriate if the authors had stated these NLR-affecting factors while evaluating the NLR as a predictor of pathologic upstaging and nonorgan-confined disease. Also, it would have been useful if the patients use steroid, antibiotic, antidiabetic, anti-inflammatory, or any other medications that could potentially affect NLR besides current medications. NLR are easily obtained by complete blood count (CBC) analysis, which is being used in almost all clinical laboratories. The authors have not defined which analyzer or analyzers were used for this study. It should not be ignored that different analyzers could provide different results. In addition, it would have been better if the authors indicated the elapsed time between obtaining the blood samples and measuring NLR, because preanalytical waiting period could affect these parameters [5]. In addition, although the authors have stated that the differential was not included as part of the routine CBC test before 2011, they mentioned later in the article that NLR was obtained from the differential of the CBC test. There is a complexity in this statement. The authors should define how they calculated NLR without having differential CBC test results before 2011. Calculating NLR without differential CBC could not be acceptable. to further studies about the predictive role of NLR upon pathologic upstaging in patients undergoing radical cystectomy. On the contrary, explanation of these concerns would certainly provide the readers clearer information.