A pre-treatment elevated neutrophil-to-lymphocyte ratio (NLR) predicts larger and aggressive renal cell carcinoma (RCC) at the time of nephrectomy, according to researchers.
A team led by Matthew K. Tollefson, MD, of Mayo Clinic in Rochester, Minn., studied 2,402 patients who underwent radical or partial nephrectomy for localized renal tumors from 1995 to 2008. Of these, 2,039 had an NLR determination made within 90 days prior to surgery. The investigators found significantly lower NLR in patients with benign rather than malignant renal masses (median 2.92 vs. 3.12), with the greatest difference observed among renal lesions larger than 7 cm (median 2.79 vs. 3.87), Dr. Tollefson and his colleagues reported online ahead of print in the World Journal of Urology.
The investigators noted a significant difference in NLR among RCC subtypes. Cystic clear-cell RCC (ccRCC) had the lowest NLR (median 2.48) and collecting duct RCC had the highest NLR (median 5.99). Results also showed that NLR increased significantly with larger tumor size and greater nuclear grade. Specifically, in patients with ccRCC, an incremental increase in tumor size was associated with greater NLR (2.80 for tumors 4 cm or less, 3.09 for tumors larger than 4 but not more than 7 cm, and 3.95 for tumors larger than 7 cm). G1, G2, G3, and G4 tumors were associated with an NLR of 2.68, 2.87, 3.48, and 5.18, respectively.
“An elevated NLR is associated with RCC pathology, higher-grade tumors, and more aggressive histologic subtypes at the time of nephrectomy,” the authors concluded. “Therefore, NLR appears to be a preoperative marker of biologically aggressive RCC and may be useful in predicting malignancy and guiding management among patients with suspicious renal tumors.”