{'fraction_non_alphanumeric': 0.03686786296900489, 'fraction_numerical': 0.02773246329526917, 'mean_word_length': 4.741573033707865, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
The Neutrophil-to-Lymphocyte Ratio before Repeat Prostate Needle Biopsy for Predicting Prostate Cancer

men (41.9%) were diagnosed to have prostate cancer. In these cohorts, none of the patients were diagnosed with pathological proven prostatitis. The NLR in prostate cancer patients was higher than that in men with no prostate cancer (3.30 ± 2.09 vs. 1.84 ± 0.75, p = 0.015; fig. 1 ). No correlation was observed between NLR and known risk factors, including the F/T PSA ratio, the digital renal examination findings, age or PSA density. To detect the cutoff point, we plotted a receiver operating curve; the candidate cutoff point for the cohort of the present study was 2.8 (area under the curve 0.729). There was no correlation between the NLR and either the Gleason Score or clinical stage. A simple, inexpensive and highly accurate method is highly desirable for daily clinical use. The NLR, which can be easily calculated from routine complete blood counts in peripheral blood samples, has been suggested to be a potentially useful predictor, not only for the systemic inflammatory response in critical care patients but also for the presence of prostate cancer [9] . Our data also indicate that the NLR functions as a biomarker to predict prostate cancer, not only in men who undergo initial needle biopsy but also in men who undergo repeat needle biopsy. The neutrophil-to-lymphocyte ratio (NLR), a simple marker of the systemic inflammatory response, has been demonstrated to be an independent prognosticator for some solid malignancies, including prostate cancer. Although one report showed that a lower neutrophil count predicts a positive prostate biopsy result, we previously reported that the NLR can predict prostatic carcinoma in men undergoing needle biopsy [1, 2] . Additionally, in combination with the free/total prostate specific antigen (F/T PSA) ratio, the positive/negative predictive value for a PSA level between 4 and 10 ng/ml would be 80.7/60.1%. Although the PSA level has a good sensitivity, the test suffers from low specificity due to the difficulty in distinguishing patients with prostate cancer versus those with benign prostatic conditions [3, 4] . Furthermore, an invasive biopsy may also miss cancer in some men, given that up to 20% of men are found to have prostate cancer on a repeat biopsy [5, 6] . On the other hand, radical prostatectomy is required to detect early stages of prostate cancer [7, 8] . From 2012 to 2015, a total of 416 men underwent multi-core ( ≥ 16) transrectal ultrasonography-guided prostate needle biopsy in our institute. Forty-three of these 416 (10.3%) men underwent repeated needle biopsy. None of the patients had systemic inflammatory disease, nor did they have any history of anti-inflammatory drug use within the 2 weeks prior to the biopsy. We retrospectively analyzed the NLR before both the repeat biopsies and performed a pathological diagnosis of prostate cancer. Eighteen of 43 Received: September 9, 2015 Accepted after revision: November 17, 2015 Published online: December 16, 2015