Clinical impact of early response to first-line VEGFR-TKI in patients with metastatic renal cell carcinoma on survival: A multi-institutional retrospective study

It remains unknown whether the early response to vascular endothelial growth factor receptor tyrosine kinase inhibitor (VEGFR-TKI) management in malignancies links to long-term survival. The objective of this study was to investigate the survival rates and predictive factors of early response in patients with metastatic renal cell carcinoma (mRCC) managed by VEGFR-TKIs. From Jan. 2008 to Oct. 2018, 496 patients were treated with VEGFR-TKIs as first-line treatment at the eight Japanese hospitals (Michinoku RCC). Early cessation was defined as VEGFR-TKIs being given up within 3 months after their initiation. The number of patients in early cessation VEGFR-TKIs (Cohort I) was 173 (34.9%), and in long-term use (Cohort II) was 323 (65.1%). The cancer-specific survival (CSS) and overall survival (OS) were better in Cohort II. IMDC Poor-risk was at risk of early cessation of a first-line VEGFR-TKI. Axitinib was the most preferred drug for long-term treatment. On closer examination, both Cohort I and II were divided into two groups, the patients ceased VEGFR-TKI due to adverse events (Group A [67 from Cohort I] and Group C [51 from Cohort II]) and disease progression (Group B [106 from Cohort I] and Group D [272 from Cohort II]). Despite that the cessation was adverse events, CSS and OS in Group A were worse than both Group C and D. Axitinib was administered with the safer profile. IMDC Poor risk was the risk factor for the early disease progression. Managing early adverse events may contribute to a better prognosis in mRCC patients treated VEGFR-TKIs.