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

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.