Prognostic importance of vitamins a, e and retinol-binding protein 4 in renal cell carcinoma patients

Abstract

Aim: To assess the prognostic importance of serum levels of retinol, retinol-binding protein 4 (RBP4) and Vitamin E at the time of diagnosis in patients with renal cell carcinoma (RCC). Patients and Methods: In this prospective study, in a cohort of 102 renal cell carcinoma patients, relationships between serum levels of the aforementioned markers and recurrence-free survival (RFS), overall survival (OS), as well as cancer-specific survival (CSS), were evaluated. The Vitamin A and Vitamin E levels were determined by high-performance liquid chromatography (HPLC), while the RBP4 level by enzyme-linked immunosorbent assay (ELISA). Results: The median followup period was 39 monthS. Renal cell carcinoma recurred in 9 patients; 23 patients died with 12 of them from RCC. The preoperative Vitamin E level was associated to RFS (p=0.02). We found a significant relationship between OS and the level of RBP4 (p=0.002), retinol (p=0.037) and Vitamin E (p=0.007). The CSS period was significantly associated with the level of RBP4 (p=0.0001) and retinol (p=0.0003). Patients with an RBP4 level less than 21.0 mg/l at the time of diagnosis had a 13.5-times higher risk of death due to RCC progression; this risk was up to 7.7-times higher with Vitamin A levels under 0.52 mg/l. Conclusion: Low levels of Vitamin A, E and RBP4 at the time of RCC diagnosis are associated with a poorer prognosis after surgery.