Durable response after discontinuation of nivolumab therapy in patients with metastatic renal cell carcinoma.

We investigated the efficacy of nivolumab treatment in patients with metastatic renal cell carcinoma who discontinued nivolumab treatment due to reasons other than disease progression. Of the 34 patients, 3 patients discontinued nivolumab therapy due to adverse events and were subsequently observed without additional treatment. The first patient discontinued nivolumab after 14 cycles of treatment due to type 1 diabetes mellitus and has maintained partial remission for 8 months. The second patient discontinued nivolumab after 11 cycles of treatment due to interstitial pneumonitis, and durable response was confirmed for 5 months. However, multiple lung lesions reappeared at 6 months after discontinuing nivolumab. The third patient discontinued nivolumab due to elevated liver enzymes after three cycles of treatment. At the time of discontinuation, a new liver lesion appeared, but the lesion decreased in size at 6 months after discontinuation. In the present study, a relatively durable response was observed in three patients who discontinued nivolumab without additional treatment.