title: Clear cell sarcoma of the kidney: a review of 351 cases from the National Wilms Tumor Study Group Pathology Center.
abstract: We reviewed 351 cases of clear cell sarcoma of the kidney (CCSK), including 182 cases entered on National Wilms Tumor Study Group (NWTSG) trials 1-4 for which clinical follow-up information was available. Tumors were restaged using NWTS 5 criteria. Mean age at diagnosis in the NWTS group was 36 months with a range of 2 months to 14 years. The male to female ratio was 2:1. Typical gross features included large size (mean diameter 11.3 cm), a mucoid texture, foci of necrosis, and prominent cyst formation. Nine major histologic patterns were identified (classic, myxoid, sclerosing, cellular, epithelioid, palisading, spindle, storiform, and anaplastic); virtually all tumors contained multiple patterns that blended with one another. Immunohistochemical stains were performed on 45 cases; only vimentin was consistently immunoreactive. Consistently negative results with other antibodies helped exclude other tumors in the differential diagnosis; all CCSKs were cytokeratin-negative, including epithelioid tumors that mimicked Wilms tumor, and MIC2-negative, including cellular tumors that mimicked primitive neuroectodermal tumor. The p53 gene product was rarely overexpressed in non-anaplastic CCSKs, but strikingly overexpressed in two of three anaplastic CCSKs. Overall survival was 69%. Multivariate analysis revealed four independent prognostic factors for survival: treatment with doxorubicin, stage, age at diagnosis, and tumor necrosis. Of note, stage 1 patients had a remarkable 98% survival rate. No other histologic or clinical variable independently correlated with survival.
authors.affiliation: Department of Pathology, The Johns Hopkins Hospital, Baltimore, Maryland 21287, USA.
authors.forename: P
authors.initials: P
authors.lastname: Argani
authors.forename: E J
authors.initials: EJ
authors.lastname: Perlman
authors.forename: N E
authors.initials: NE
authors.lastname: Breslow
authors.forename: N G
authors.initials: NG
authors.lastname: Browning
authors.forename: D M
authors.initials: DM
authors.lastname: Green
authors.forename: G J
authors.initials: GJ
authors.lastname: D'Angio
authors.forename: J B
authors.initials: JB
authors.lastname: Beckwith
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007223:Infant; D007668:Kidney / Q000473:pathology; D007680:Kidney Neoplasms / Q000175:diagnosis / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D008297:Male; D015999:Multivariate Analysis; D009373:Neoplasms, Germ Cell and Embryonal / Q000175:diagnosis / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D009392:Nephrectomy; D011379:Prognosis; D012737:Sex Factors; D016019:Survival Analysis; D013997:Time Factors