title: Multinodular hyperplastic pannephric nephroblastomatosis with tubular differentiation: a new morphologic variant.
abstract: We report a case of bilateral nephromegaly detected prenatally with oligohydramnios. Delivered at 35 weeks, this black male infant rapidly developed renal failure, requiring dialysis. He lived 3 1/2 months. The kidneys were three times normal size and diffusely multinodular, with hypoplastic calyces, no corticomedullary demarcation, and no pyramids. Histologically, they revealed hyperplastic embryonal rests composed of tubules and ducts with prominent branching. The nodular rests were intermixed with areas of mature parenchyma, which showed prominent oxalosis. By flow cytometry, rests were diploid, with an S-phase fraction of 25.9%. The proliferation of embryonal collecting system analogs is attributed to excessively rapid and prolonged branching of the ureteric bud, dating from the fourth gestational month or earlier. This unique case may represent a new morphologic variant of universal nephroblastomatosis.
authors.affiliation: Division of Pediatric Pathology, Jackson Memorial Medical Center, University of Miami School of Medicine, Florida 33101, USA.
authors.forename: J J
authors.initials: JJ
authors.lastname: Regalado
authors.forename: M M
authors.initials: MM
authors.lastname: Rodriguez
authors.forename: J B
authors.initials: JB
authors.lastname: Beckwith
mesh_terms: D017809:Fatal Outcome; D006801:Humans; D007231:Infant, Newborn; D007680:Kidney Neoplasms / Q000473:pathology*; D008297:Male; D009378:Neoplasms, Multiple Primary / Q000473:pathology*; D011230:Precancerous Conditions / Q000473:pathology; D009396:Wilms Tumor / Q000473:pathology*