Categories of response to first line vascular endothelial growth factor receptor targeted therapy and overall survival in patients with metastatic renal cell carcinoma

Introduction: Sequential use of targeted therapy (TT) has improved overall survival (OS) of patients with metastatic renal cell carcinoma (mRCC). The value of objective response (OR) as compared to stable disease (SD) is unclear. We aimed to investigate OR of first-line TT and its impact on OS. Material and methods: Retrospective analysis of OS among 331 mRCC patients with a first-line assessment according to RECIST 1.0. Characteristics between objective responders (complete response [CR] or partial remission [PR]), patients with SD and non-responders (progressive disease [PD] and toxicity [Tox]) were compared with the Chi-square test and the Kruskal-Wallis test. Kaplan-Meier analysis of OS and progression-free survival (PFS). Cox model analysis of Predictors of OS. Results: Best response was CR, PR, SD, PD and Tox in 9 (2.7%), 61 (18.4%), 167 (50.5%), 80 (24.2%) and 14 (4.2%) patients respectively resulting in an OR rate of 21%. Median OS in months: CR 63.2; PR 37.6; SD 35.9; PD 14.6; TOX 22.5 (p < 0.0001). Median PFS for responders was 14.8, 11.5 for patients with SD and 2.5 for non-responders (p < 0.0001). Similarly median OS was 38.7, 35.9 and 15.5 (p < 0.00001). Primary resistance and a first-line PFS < 6 months were the strongest independent predictors of OS. The achievement of OR as compared to SD did not impact OS. Conclusions: In our cohort of unselected patients OR was not associated with superior OS as compared to SD. (C) 2013 Elsevier Ltd. All rights reserved.