Pretreatment Serum Prealbumin as an Independent Prognostic Indicator in Patients With Metastatic Renal Cell Carcinoma Using Tyrosine Kinase Inhibitors as First-Line Target Therapy

Abstract

Background: Although serum prealbumin is a sensitive marker to assess malnutrition, its prognostic impact in patients with metastatic renal cell carcinoma (mRCC) remains elusive.

Methods: Patients' data were retrospectively retrieved from the medical records of Renji Hospital affiliated to Shanghai Jiao Tong University School of Medicine from March 2006 to July 2015 to access overall survival (OS) and progression-free survival (PFS). The survival outcomes of patients with low pretreatment prealbumin (< 200 mg/L) and high pretreatment prealbumin (≥ 200 mg/L) were compared using a log-rank test and Cox proportional hazard regression model. Prognostic accuracy was determined using the Harrell concordance index (c-index).

Results: The median PFS and OS for 143 patients were 11 months (95% confidence interval [CI], 9-14 months) and 27 months (95% CI, 22-39 months), respectively. The low pretreatment prealbumin group had significantly shorter median PFS (6 vs. 14 months, P < .001) and OS (10 vs. 34 months, P < .001) than the normal pretreatment prealbumin group. Multivariate analysis showed that pretreatment prealbumin was an independent predictor of OS (hazard ratio [HR] 1.963; 95% CI, 1.140-3.381; P = .015) and also an independent predictor of PFS (HR 2.021; 95% CI, 1.227-3.329; P = .006). Further, addition of pretreatment prealbumin to the Heng model enhanced the predictive accuracy of PFS and OS (c-index: 0.70 and 0.74) compared with the Heng model alone (c-index: 0.69 and 0.72).

Conclusion: Low pretreatment serum prealbumin is an independent prognosticator of risk and survival outcomes in patients with mRCC receiving tyrosine kinase inhibitors as first-line treatment and also increases the accuracy of established prognostic models.

Keywords: Pretreatment prealbumin; Prognosis; Renal cell carcinoma; Sorafenib; Sunitinib.