Immune Checkpoint Inhibitors in the Pre-operative Setting and Impact on the Primary Renal Tumor.

The treatment paradigm for metastatic renal cell cancer (RCC) has changed dramatically over the last decade with the United States Food and Drug Administration’s (FDA) approval of various combination regimens with a backbone of immune checkpoint inhibitors (ICI) [1–5]. Despite the documented efficacy of ICIs in the metastatic setting, many patients either do not respond or become resistant after an initial response. Furthermore, even after curative surgery for early stage kidney cancer, up to 60% of the highest risk patients are predicted to relapse [6]. Recently, the ICI pembrolizumab was approved by the FDA for use in the adjuvant setting following the positive results of a phase III trial showing a modest improvement in disease-free survival in favor of pembrolizumab compared to placebo [7]. However, the results of subsequent phase III trials using other ICIs in the adjuvant setting did not improve outcomes [8–10]. There is therefore a need to constantly modify treatment algorithms for patients with RCC. Exposure of tumors to pre-operative ICIs, either before