Significance of timing of therapeutic line on effectiveness of nivolumab for metastatic renal cell carcinoma

Objectives:This study aimed to clarify the significance of therapeutic timing on the effectiveness of nivolumab for treating metastatic renal cell carcinoma.Marterials and methods:Fifty-eight patients with metastatic renal cell carcinoma treated with nivolumab monotherapy were retrospectively studied.Patients who were treated with nivolumab as second-line therapy were included in the second-line group,while the others were included in the later-line group.The clinicopathological characteristics,effects of nivolumab,and prognoses of these groups were compared.Results:Twenty and thirty-eight patients were included in the second-line and later-line groups,respectively.There were no significant differences in the distribution of International Metastatic Renal Cell Carcinoma Database Consotium risk and other clinicopathological characteristics between the 2 groups.The proportion of patients whose objective best response was progressive disease in the second-line group was significantly lower than that in the later-line group(15%vs.50%,p=0.0090).The 50%progression-free survival with nivolumab in the second-line group was significantly better than that in the later-line group(not reached and 5 months,p=0.0018).Multivariate analysis showed that the second-line setting was an independent predictive factor for better progression-free survival(p=0.0028,hazard ratio=0.108).The 50%overall survival after starting nivolumab in the second-line and later-line groups was not reached and 27.8 months,respectively(p=0.2652).Conclusions:The therapeutic efficacy of nivolumab as second-line therapy is expected to be better than that of later therapy.