title: Bilaterally multicentric synchronous Wilms' tumor: successful conservative treatment despite persistence of nephrogenic rests.
abstract: We report a case of synchronous bilateral Wilms' tumor in a girl with incomplete Beck-with-Wiedemann syndrome and hemihypertrophy. Multiple small tumors were present in both kidneys. The initial diagnostic biopsy showed stage I monophasic blastematous Wilms' tumor of favorable histology, with multiple perilobar nephrogenic rests (nephroblastomatosis). By flow cytometry, tumor was diploid, with an S-phase fraction of 13.9%. Dactinomycin and vincristine were begun as per the National Wilms' Tumor Study IV (18 week course). After 1 month, only a single small lesion was evident, which persisted unchanged. Excisional biopsy 5 months after beginning chemotherapy showed entirely necrotic tumor but apparently unaltered nephrogenic rests. After completing chemotherapy, the child has done well, with normal renal function and no evidence of disease 3 years after diagnosis. Management of stage V Wilms' tumor is tailored to the individual case, being as conservative as possible to spare renal parenchyma. Given the high incidence of coexisting nephrogenic rests in bilateral Wilms' tumor, careful follow-up is required, as these potentially premalignant rests may resist chemotherapy.
authors.affiliation: Department of 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: S
authors.initials: S
authors.lastname: Toledano
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001506:Beckwith-Wiedemann Syndrome / Q000150:complications; D017024:Chemotherapy, Adjuvant; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000150:complications / Q000473:pathology* / Q000628:therapy*; D009378:Neoplasms, Multiple Primary / Q000150:complications / Q000473:pathology / Q000628:therapy*; D009392:Nephrectomy / Q000379:methods; D009396:Wilms Tumor / Q000150:complications / Q000473:pathology* / Q000628:therapy*