Prognostic significance of serum albumin in patients with metastatic renal cell carcinoma

Abstract

Systemic inflammation has been suggested to impact on the prognosis of metastatic renal cell carcinoma (mRCC). We undertook a retrospective analysis of patients with mRCC treated at Akademiska University Hospital in Sweden during the years 2005-2012 to assess the possible prognostic significance of inflammation-related factors including serum albumin, platelet count, weight loss and C-reactive protein (CRP). The Memorial Sloan-Kettering Cancer Center (MSKCC) criteria for prognosis of mRCC and ECOG performance status were assessed for all patients. Overall survival (OS) and progression-free survival (PFS) were calculated according to Kaplan-Meier, and Cox proportional hazards regression was used for uni- and multivariate analyses. The median OS of all patients (n=84) was 20 months. Univariate analysis identified low serum albumin (HR=4.17, p<0.001), elevated platelet count (HR=2.98, p<0.001) and patient-reported weight loss prior to diagnosis of mRCC (HR=2.73, p<0.001), in addition to MSKCC (HR=3.35, p=0.0088) to be associated with shorter OS. CRP did not significantly affect OS. Serum albumin retained prognostic significance for OS in multivariate analysis (HR=2.72, p=0.015). In patients treated with an angiogenesis-targeted agent (n=47), low serum albumin level (HR=4.63, p<0.001) and elevated platelet count (HR=2.11, p=0.022) were associated with shorter PFS. In contrast, CRP, weight loss and MSKCC risk group did not significantly affect PFS. In multivariate analysis serum albumin remained associated with PFS (HR=3.92, p=0.0035). Our findings identify serum albumin as an independent prognostic factor for patients with mRCC treated with angiogenesis-targeted therapy.