Therapeutic role of deferred cytoreductive nephrectomy in patients with metastatic renal cell carcinoma treated with nivolumab plus ipilimumab.

OBJECTIVES: To explore the therapeutic role of deferred cytoreductive nephrectomy in patients with metastatic renal cell carcinoma treated with nivolumab plus ipilimumab. PATIENTS AND METHODS: Forty-one patients with synchronous metastatic renal cell carcinoma who received nivolumab plus ipilimumab as first-line systemic therapy at our affiliated institutions were retrospectively evaluated. We focused on the prognosis, including tumor responses in primary kidney and metastatic lesions in patients treated with deferred cytoreductive nephrectomy. In addition, the overall survival according to nephrectomy status (i.e. deferred cytoreductive nephrectomy vs. upfront cytoreductive nephrectomy vs. without cytoreductive nephrectomy) was compared. RESULTS: During a median follow-up period of 12.0 months, seven (30%) patients received deferred cytoreductive nephrectomy at a median time of 10.4 months after nivolumab plus ipilimumab initiation. All the patients showed tumor shrinkage in their primary kidney lesions, including six (86%) patients with ≥30% of shrinkage. Metastatic lesions were also shrunk by ≥30% in six (86%) patients, including two (29%) obtaining complete response. At the last time of follow-up, three (43%) patients were disease-free. The overall survival rate after nivolumab plus ipilimumab initiation tended to be higher in patients with deferred cytoreductive nephrectomy compared with those with upfront cytoreductive nephrectomy (1-year survival rate: 100% vs. 72.4%, P = 0.0587) and those without cytoreductive nephrectomy (vs. 58.2%, P = 0.0613). CONCLUSIONS: The present retrospective data showed that deferred cytoreductive nephrectomy had the potential to exert a therapeutic effect in a subset of patients who obtained favorable tumor responses to nivolumab plus ipilimumab for a certain period. Prospective randomized clinical trials are needed to confirm the prognostic impact of deferred cytoreductive nephrectomy after frontline immunotherapy in synchronous metastatic renal cell carcinoma.