Monomorphous histiocytoma in a child. Report of a case with ultrastructural features suggestive of dendritic cell differentiation.
The authors describe a rapidly growing soft tissue tumor of predominantly histiocytic composition in an 8-year-old child. The tumor cells were identified as elements of the mononuclear phagocyte system by histologic, histochemical, immunologic, and electron microscopic study. Despite the presence of a minor fibroblastic component, the tumor did not conform to established criteria for a diagnosis of malignant fibrous histiocytoma. Formation of frequent desmosome-like intercellular junctions raised the possibility of dendritic reticulum cell differentiation, since the latter cells seem to be the only elements of the mononuclear phagocyte system that display such specialized cell junctions. The results of immunostaining were discrepant with those reported for normal dendritic reticulum cells, but the currently available information makes it doubtful that the entire neoplastic spectrum of dendritic cell differentiation can currently be diagnosed in surgical pathology.
Gonzalez-Crussi
F
F
Department of Pathology, Children's Memorial Hospital, Chicago, Illinois 60614.
Czapar
C A
CA
Chou
P
P
D002648:Child; D003593:Cytoplasm / Q000648:ultrastructure; D003713:Dendritic Cells / Q000648:ultrastructure*; D003896:Desmosomes / Q000648:ultrastructure; D005260:Female; D005350:Fibroma / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D012983:Soft Tissue Neoplasms / Q000473:pathology*; D013848:Thigh