The importance of serum osteopontin and stanniocalcin-1 in renal cell carcinoma

A total of 56 RCC patients with staging ≥ pT1b were enrolled in a prospective study to assess the prognostic importance of serum levels of osteopontin (OP), stanniocalcin-1 (SC), FGF-23, alpha Klotho and 25-OH-D at the time of diagnosis in renal cell carcinoma (RCC) patients. The relationship between the serum level of the analyzed parameters and recurrence-free survival (RFS), overall survival (OS) and cancer-specific survival (CSS) was examined, and our control group consisted of 20 patients without cancer. The levels of osteopontin, stanniocalcin-1, FGF-23 and alpha Klotho were determined by Enzyme-Linked Immunosorbent Assay (ELISA) and 25-OH-D by chemiluminiscence immunoanalysis (CLIA). The follow-up period median was 46 months. Renal cell carcinoma recurred in 9 patients and 20 patients died during follow-up; 12 of them from RCC. The level of osteopontin and stanniocalcin-1 varied between the control group and RCC patients (at p=0.02 and p=0.0003). Higher levels of stanniocalcin-1 were detected in the metastatic RCC group than in the localized RCC group (p=0.003). Only the stanniocalcin-1 level at the time of surgery was associated with RFS (p=0.0004). Both OS and CCS were associated with the osteopontin, stanniocalcin-1 and FGF preoperative level. Patients with stanniocalcin-1 level over 1,277 pg/ml and osteopontin level over 100 ng/ml had 17.8 times higher and 7.9 times higher risk of dying from RCC progression, respectively (p