Background: The discrepant concordance between biopsy and radical prostatectomy (RP) specimen are well reported. To validate the clinical usefulness of neutrophil-lymphocyte ratio (NLR) in discriminating real GS ≥ 7 PCa from biopsy-based GS ≤ 6 PCa in comparison with serum total prostate-specific antigen (tPSA) and value of their combination.
Methods: One hundred one patients who underwent physical examinations incidentally found elevated tPSA and subsequently received biopsy with a conclusion of GS ≤ 6 and RP with an interval of 4-6 weeks after biopsy were enrolled. NLR and tPSA were obtained within 15 days prior to biopsy. Logistic regression model was applied appropriately; McNemar tests and AUC model were performed to evaluate differences among tPSA, NLR and their combination and corresponding diagnostic power respectively.
Results: The pathological results from RP specimen comprised 61 patients with GS ≤ 6 and 100 patients with GS ≥ 7. Higher tPSA and NLR were significantly associated with patients with actual GS ≥ 7 (All P < 0.05) concurrently. Multivariate logistic regression indicated that tPSA (OR = 1.088, 95% C.I. = 1.029-1.151, P = 0.003) and NLR (OR = 1.807, 95% C.I. = 1.021-3.200, P = 0.042) could be independent predictors for GS groupings. Under cutoff value of 14.09 ng/ml for tPSA and 2.25 for NLR, the sensitivity, specificity and accuracy were 60.0%, 80.3% and 67.7% for tPSA, 42%, 88.5% and 59.6% for NLR, and 71.0%, 75.4% and 72.7% for combination of tPSA and NLR (tPSA + NLR) respectively. The sensitivity of tPSA + NLR was significantly higher in comparison with tPSA (P = 0.001) and NLR (P < 0.001). Except for sensitivity, no significant difference was found between tPSA and NLR in specificity (P = 0.227) and accuracy (P = 0.132). tPSA got the largest AUC with 0.732 (p < 0.001, 95% C.I.: 0.651-0.813).
Conclusions: Serum tPSA and NLR were significantly elevated among GS ≥ 7 PCa concurrently. The combination of tPSA and NLR might have additional benefit to biopsy on discriminating real GS ≥ 7 Pca from biopsy-based GS ≤ 6 PCa. More stratification models and prospectively multicenter studies are necessary.
Keywords: Neoplasm grading; Prostate cancer; Systemic inflammatory index; Watchful waiting.