Background: The pretreatment neutrophil-to-lymphocyte ratio has prognostic value after radical prostatectomy for treating localized prostate cancer. However, the use of postoperative neutrophil-to-lymphocyte ratio has not been evaluated in this population. We investigated the prognostic significance of early postoperative neutrophil-to-lymphocyte ratio after radical prostatectomy for prostate cancer.
Methods: We retrospectively reviewed clinical data from 2,302 patients with localized prostate cancer who underwent radical prostatectomy at our institution between years 2000 and 2010. Only patients with pre- and postoperative complete blood counts with differential results were included. Patients who received neoadjuvant or postoperative adjuvant treatment and those without adequate medical records were excluded. Kaplan-Meier analyses were performed to analyze biochemical recurrence-free survival and overall survival rates. Univariate and multivariate Cox regression models were used for each endpoint.
Results: Kaplan-Meier curves showed that high postoperative neutrophil-to-lymphocyte ratio (>3.5) was significantly associated with decreased biochemical recurrence-free survival (p = 0.009) and overall survival (p = 0.010). In the univariate and multivariate Cox regression analyses, high postoperative neutrophil-to-lymphocyte ratio was a significant predictor of biochemical recurrence (hazard ratio 1.270, p = 0.008) and overall survival (hazard ratio 1.437, p = 0.033).
Conclusions: Our results demonstrate that postoperative neutrophil-to-lymphocyte ratio is an independent factor for biochemical recurrence and overall survival in patients who underwent radical prostatectomy for prostate cancer. These findings suggest that neutrophil-to-lymphocyte ratio can be a potentially valuable tool for stratifying high-risk patients and facilitating choices of postoperative therapy in patients with prostate cancer.
Keywords: biochemical recurrence; neutrophil-to-lymphocyte ratio; prostate cancer; radical prostatectomy; survival.