Platelet to lymphocyte ratio plays an important role in prostate cancer's diagnosis and prognosis.

Objective: To compare the platelet to lymphocyte ratio (PLR) in normal people, benign prostatic hyperplasia (BPH) patients and prostate cancer (PCA) patients, and to explore the prognostic role of PLR in PCA.

Methods: 155 normal people, 168 BPH patients and 103 PCA patients were enrolled. PCA patients were divided into PLR low value group (PLR<150) and PLR high value group (PLR≥150), and the difference of patients' clinical characteristics between high value group and low value group was comparative studied.

Results: The differences of PLR among normal people, BPH patients and PCA patients were statistically significant. In addition, platelet counts, neutrophil counts, PSA level, LDH level, AKP level, CRP level and alkaline phosphatase level were also significantly increased in PLR high value group, while the hemoglobin level was decreased. Besides, serious events such as coma during hospitalization were also more likely to appear in PLR high value group. PCA patients had an average follow-up of 3 years, and a total of 25 cases of patients died, including 11 (16.4%) cases in the PLR low value group, and 14 (38.9%) cases in PLR high value group with. Three years survival rate of patients in high value group was significantly reduced. Additionally, PLR was a possible risk factor associated with mortality, and an independent predictor of all-cause mortality during follow-up.

Conclusion: PLR is significantly increased in PCA patients, and it is an independent predictor of 3-year mortality in PCA patients.