Does red blood cell distribution width predict prognosis in metastatic renal cell carcinoma patients using first-line vascular endothelial growth factor receptor tyrosine kinase inhibitor therapy?

Aim: It is red cell distribution width (RDW) that has been reported to show an inflammatory response which has been studied recently. The aim of this study is to investigate whether the pre-treatment RDW in patients using first-line vascular endothelial growth factor tyrosine kinase inhibitor (VEGFR TKI) with the diagnosis of metastatic renal cell carcinoma (mRCC) predicts treatment response and is a prognostic factor or not.

Methods: About 92 patients diagnosed with mRCC who were being treated with sunitinib or pazopanib in the first line between January 2015 and June 2021 were included in the study. The patients were divided into 2 groups, as being ≤15.3 and >15.3, according to the RDW cut-off value calculated by ROC analysis.

Results: The mOS of patients with a RDW of ≤15.3% was 45.0 (30.0-59.9) months, and of 21.3 (10.4-32.2) in those with a RDW of >15.3%. This difference was statistically significant (p < 0.001). In the group of patients with a RDW of ≤15.3, median progression free survival (mPFS) (38.04 [16.3-59.7] months) was found to be significantly higher than those with a RDW of >15.3 (17.1 [11.8-22.5] months) (p = 0.04). In multivariate analysis, RDW level (≤15.3, >15.3), was determined to be prognostic markers (p = 0.022).

Conclusion: In mRCC patients, the RDW value measured before first-line VEGFR TKI therapy is an independent prognostic marker.