Long-term survival of a kidney transplant patient with advanced renal cancer after combination therapy: a case report and literature review

De novo renal transplant carcinoma, especially in the context of bilateral renal carcinoma, is rare and often presents as small, low-grade papillary renal cell carcinoma (RCC). There is currently no consensus or effective treatment for advanced metastatic RCC after kidney transplantation. A 40-year-old man developed de novo renal transplant carcinoma with venous thrombus and lung metastases 13 years after transplantation. The patient underwent cytoreductive nephrectomy followed by sequential treatment with tyrosine kinase inhibitors (TKI) and anti-PD-1 monoclonal antibodies. After 2 years, the patient showed excellent graft function with no evidence of cancer progression. Despite subsequent graft failure, the disease remained controlled for more than 2 years and the patient survived for more than 3 years, which was significantly longer than the typical survival of 10 to 20 months in patients with advanced kidney cancer. The results suggest that combining cytoreductive nephrectomy with TKI and anti-PD-1 therapy may significantly prolong survival in patients with renal allograft carcinoma.