Pretreatment Serum Cystatin C Levels Predict Renal Function, but Not Tumor Characteristics, in Patients with Prostate Neoplasia

To evaluate the role of Cystatin C (Cys-C) in tumorigenesis and progression of prostate cancer (PCa), we retrospectively collected the clinical information from the records of 492 benign prostatic hyperplasia (BPH), 48 prostatic intraepithelial neoplasia (PIN), and 173 PCa patients, whose disease was newly diagnosed and histologically confirmed. Pretreatment serum Cys-C levels were compared across the various groups and then analyzed to identify relationships, if any, with clinical and pathological characteristics of the PCa patient group. There were no significant differences in serum Cys-C levels among the three groups (P > 0.05). In PCa patients with normal SCr levels, patient age was correlated with serum Cys-C level (P ≤ 0.001) but did not correlate with alkaline phosphatase (AKP), lactate dehydrogenase (LDH), prostate specific antigen (PSA), Gleason score, or bone metastasis status (P > 0.05). Age and SCr contributed in part to the variations in serum Cys-C levels of PCa patients (r = 0.356, P ≤ 0.001; r = 0.520, P ≤ 0.001). In conclusion, serum Cys-C levels predict renal function in patients with prostate neoplasia, but were not a biomarker for the development of prostate neoplasia, and were not correlated with the clinicopathological characteristics of PCa.