title: Collecting duct carcinoma arising in association with BK nephropathy post-transplantation in a pediatric patient. A case report with immunohistochemical and in situ hybridization study.
abstract: The development of malignancy in a renal transplant graft is an uncommon phenomenon. A renal neoplasm developing in the adult donor kidney of a pediatric transplant recipient has only rarely been reported. We report a case of collecting duct carcinoma arising in association with BK virus nephropathy in an adult living-related donor renal allograft to a pediatric recipient. Our case is the second report of neoplasia occurring in association with BK virus nephropathy post-transplantation, suggesting that BK virus may play a role in oncogenesis. It has been proposed that the T-Ag protein encoded by the polyomavirus family of viruses disrupts chromosomal integrity, creating oncogenes, and inactivating tumor suppressor genes. In our study, immunohistochemical staining with antibody directed against BK virus large T antigen showed nuclear staining within urothelium, tubular epithelium, tubular intraepithelial neoplasia, and invasive carcinoma. In situ hybridization did not identify BK virus DNA within neoplastic cells. T-Ag protein expression has been shown to be tumor-specific in bladder, gastric, and colorectal cancers. The finding of T-Ag protein expression in both intraepithelial and invasive neoplastic tissues in our case raises the possibility of BK virus as a causative agent in oncogenesis.
authors.affiliation: Department of Pathology, University of Utah School of Medicine and Associated Regional and University Pathologists (ARUP) Laboratories, Salt Lake City, UT, USA. lyska.emerson@hsc.utah.edu
authors.forename: Lyska L
authors.initials: LL
authors.lastname: Emerson
authors.forename: Heather M
authors.initials: HM
authors.lastname: Carney
authors.forename: Lester J
authors.initials: LJ
authors.lastname: Layfield
authors.forename: Joseph R
authors.initials: JR
authors.lastname: Sherbotie
mesh_terms: D001739:BK Virus / Q000235:genetics* / Q000276:immunology; D002277:Carcinoma / Q000150:complications / Q000276:immunology / Q000821:virology*; D002648:Child; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D017403:In Situ Hybridization; D007674:Kidney Diseases / Q000150:complications / Q000628:therapy / Q000821:virology*; D007680:Kidney Neoplasms / Q000150:complications / Q000276:immunology / Q000821:virology*; D016030:Kidney Transplantation / Q000009:adverse effects / Q000379:methods; D007685:Kidney Tubules, Collecting / Q000473:pathology*; D008297:Male; D009361:Neoplasm Invasiveness; D011184:Postoperative Period