As Dr. George had pointed out, it is interesting to note that Nivolumab can lead to a tumor flare phenomenon making RECIST criteria difficult to interpret when determining treatment response. Dr. Quinn also made a good point about the duration of treatment when we observe lesions increasing in size on scans.
Given these potential confounding factors, how does one assess for treatment failure in patients with metastatic RCC? How long should we maintain patients on treatment before calling it a failure? Would the authors or experts elaborate on this point?