Derivation of nephrogenic adenomas from renal tubular cells in kidney-transplant recipients.
BACKGROUND
Nephrogenic adenomas are benign, tumor-like lesions within the urothelial mucosa of the urinary tract that are not uncommon in renal-transplant recipients. We investigated the origin of nephrogenic adenomas in renal-transplant recipients.


METHODS
Tissue sections were analyzed by fluorescence in situ hybridization with the use of probes for the X and Y chromosomes, by immunohistochemical methods with the use of antibodies to renal tubular antigens, and by lectin histochemical methods. Forty-six nephrogenic adenomas from 29 patients were analyzed.


RESULTS
All nephrogenic adenomas in 14 female recipients of transplants from male donors and 10 male recipients of transplants from female donors showed the same sex-chromosome status as the donor kidney, but not the same sex-chromosome status as the recipient's surrounding bladder tissue. The nephrogenic adenomas from all 6 female recipients of transplants from female donors showed female chromosomes, and those from the 16 male recipients of transplants from male donors showed male chromosomes. The presence of aquaporin 1, PAX2, and lectin-binding capacity for peanut agglutinin, Lotus tetragonolobus agglutinin, and Sophora japonica agglutinin in nephrogenic adenomas indicated an origin from renal tubular cells.


CONCLUSIONS
Nephrogenic adenomas in renal-transplant recipients are derived from tubular cells of the renal transplants and are not metaplastic proliferations of the recipient's bladder urothelium.
Department of Clinical Pathology and Center of Excellence in Clinical and Experimental Oncology, University of Vienna General Hospital, Austria.
Peter R
PR
Mazal
Roland
R
Schaufler
Romana
R
Altenhuber-Müller
Andrea
A
Haitel
Bruno
B
Watschinger
Christian
C
Kratzik
Georg
G
Krupitza
Heinz
H
Regele
Franz T
FT
Meisl
Othmar
O
Zechner
Dontscho
D
Kerjaschki
Martin
M
Susani
D000236:Adenoma / Q000235:genetics* / Q000473:pathology; D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D016030:Kidney Transplantation / Q000009:adverse effects*; D007684:Kidney Tubules / Q000166:cytology*; D008297:Male; D008875:Middle Aged; D012730:Sex Chromosomes; D001743:Urinary Bladder / Q000473:pathology; D001749:Urinary Bladder Neoplasms / Q000235:genetics* / Q000473:pathology