title: Primitive pelvic sarcoma resembling clear cell sarcoma of kidney.
abstract: Clear cell sarcoma of kidney (CCSK) is an aggressive childhood renal tumor of unknown histogenesis that has not been reported to occur outside the kidney. The article describes an extrarenal neoplasm arising in the pelvic soft tissues of a 13-year-old boy that was composed predominantly of uniform mesenchymal cells with optically clear cytoplasm supported by an arborizing network of small blood vessels, which was indistinguishable in appearance from CCSK. The electron microscopic findings, although nonspecific, were essentially identical to those of CCSK, with tumor cells displaying fine chromatin, electron-lucent cytoplasm, and intercellular collagen but no evidence of tissue-specific differentiation. Immunocytochemical studies showed positivity for vimentin but negative results for desmin, myoglobin, cytokeratin, epithelial membrane antigen, S-100 protein, neuron-specific enolase and factor VIII-related antigen. Tumor cells were also nonreactive with Ulex lectin. This unusual pelvic tumor and CCSK may both derive from primitive mesenchymal cells and may represent phenotypic but not necessarily histogenetic analogs.
authors.affiliation: Department of Pathology, Loma Linda University Medical Center, California 92354.
authors.forename: D A
authors.initials: DA
authors.lastname: Weeks
authors.forename: R L
authors.initials: RL
authors.lastname: Malott
authors.forename: C
authors.initials: C
authors.lastname: Zuppan
authors.forename: G W
authors.initials: GW
authors.lastname: Mierau
authors.forename: J B
authors.initials: JB
authors.lastname: Beckwith
mesh_terms: D000293:Adolescent; D003937:Diagnosis, Differential; D006801:Humans; D007150:Immunohistochemistry; D007680:Kidney Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000648:ultrastructure; D008297:Male; D008854:Microscopy, Electron; D010386:Pelvic Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000648:ultrastructure; D012509:Sarcoma / Q000175:diagnosis* / Q000473:pathology / Q000648:ultrastructure; D014746:Vimentin / Q000032:analysis
chemical_list: D014746:Vimentin