Resolution of a High Grade and Metastatic BK Polyomavirus-Associated Urothelial Cell Carcinoma Following Radical Allograft Nephroureterectomy and Immune Checkpoint Treatment: A Case Report

Transplant Proc. 2020 Nov;52(9):2720-2725. doi: 10.1016/j.transproceed.2020.06.012. Epub 2020 Jul 30.


Background: BK viral infection in the posttransplant setting continues to cause serious morbidity with effects ranging from allograft nephropathy and dysfunction to urothelial malignancy.

Results: In this report, we present a patient that developed BK-associated nephropathy and, 6 years later, locally advanced urothelial malignancy in the renal allograft with nodal, muscle, and extremity involvement. Following radical allograft nephroureterectomy, he was treated with palliative radiation and the immune checkpoint inhibitor atezolizumab. Follow-up imaging at 1 year demonstrated radiographic complete response.

Conclusions: This report supports the growing body of evidence supporting the association of urothelial malignancy and BK virus infection in renal transplant recipients. Further, it highlights the novel application of immune checkpoint inhibitors in the treatment of advanced posttransplant malignancy, in particular when the allograft is removed and the tumor is possibly of donor origin.

Publication types

  • Case Reports

MeSH terms

  • Allografts / surgery
  • Allografts / virology*
  • Antibodies, Monoclonal, Humanized / therapeutic use*
  • BK Virus
  • Carcinoma, Transitional Cell / therapy*
  • Carcinoma, Transitional Cell / virology*
  • Humans
  • Kidney Neoplasms / therapy*
  • Kidney Neoplasms / virology*
  • Kidney Transplantation
  • Male
  • Middle Aged
  • Nephroureterectomy
  • Polyomavirus Infections / complications
  • Polyomavirus Infections / virology
  • Transplantation, Homologous
  • Tumor Virus Infections / complications
  • Tumor Virus Infections / virology


  • Antibodies, Monoclonal, Humanized
  • atezolizumab