Papillary renal cell carcinoma (RCC) is a rare form of RCC, occurring in about 10-15% of RCC cases. A recent multi-centre retrospective study looked at the outcomes of patients with metastatic papillary RCC treated with immune checkpoint inhibitors alone. Patients had to have been treated with an immune checkpoint inhibitor, at any time point in their course of treatment.
Fifty-seven patients were included in the study. The majority (95%) of patients were treated with nivolumab. Patients were followed for a median of 12 months. The median time to treatment failure was 3.1 months, objective response rate was 11% and 33% of patients had stable disease. The median overall survival was 14.6 months.
Six patients experienced severe or life-threatening adverse events leading to discontinuation of treatment.
This study showed that immune checkpoint inhibitors had limited activity in patients with papillary RCC, and further trials are needed to explore potential therapeutic options.