A case of metastatic Xp11.2 translocation renal cell carcinoma showing a prolonged response to nivolumab as 6th-line treatment.

A female patient with Xp11.2 translocation renal cell carcinoma developed lung metastasis 24 months after partial nephrectomy that was performed at the age of 32. Sunitinib, everolimus, axitinib, temsirolimus and pazopanib were sequentially administered for 55 months and disease progression was observed. Then nivolumab was started as 6th-line treatment. After a transient increase in tumor size, metastatic tumors started to shrink. Eventually, nivolumab provided a partial response with a 35% reduction of tumor size at 50 months and freedom from progression for 60 months. The present case suggests that immune checkpoint inhibitors are effective in selected cases with Xp11.2 translocation renal cell carcinoma.