title: Primitive myxoid mesenchymal tumor of infancy: report of two cases and review of the literature.
abstract: Primitive myxoid mesenchymal tumor of infancy is a recently recognized soft tissue tumor with only a few cases reported. Here, we reported another two cases of the lesion, a 5-month-old boy presenting with a soft tissue mass in the neck region that recurred 2 months later and a 3-day-old girl with a congenital superficial dorsal lumbar mass that extended to the spinal canal 1 month later. They shared similar histological patterns, such as unusual diffuse myxoid background, delicate vascular network, small cystic spaces, low to moderate cellularity, and primitive mesenchymal tumor cells. Immunohistochemically, the tumor cells showed positive for vimentin, CD99, CD117 and nestin, negative for myoid, lipoblastic, histiocytic, and neural markers. In conclusion, primitive myxoid mesenchymal tumor of infancy is a distinctive entity with its own clinical pathological features. Expression of CD99, CD117 and nestin may be consistent with the primitive nature of the tumor and may serve as ancillary markers for differential diagnosis from the other infantile tumors.
authors: Department of Pathology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
authors: Qixing
authors: Q
authors: Gong
authors: Zhen
authors: Z
authors: Wang
authors: Xiao
authors: X
authors: Li
authors: Qinhe
authors: Q
authors: Fan
mesh_terms: D000071443:12E7 Antigen; D015703:Antigens, CD / Q000378:metabolism; D014408:Biomarkers, Tumor; D015815:Cell Adhesion Molecules / Q000378:metabolism; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007381:Intermediate Filament Proteins / Q000378:metabolism; D008297:Male; D008637:Mesenchymoma / Q000151:congenital / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D009364:Neoplasm Recurrence, Local; D009419:Nerve Tissue Proteins / Q000378:metabolism; D064231:Nestin; D019009:Proto-Oncogene Proteins c-kit / Q000378:metabolism; D012983:Soft Tissue Neoplasms / Q000151:congenital / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D014746:Vimentin / Q000378:metabolism
chemical_list: D000071443:12E7 Antigen; D015703:Antigens, CD; D014408:Biomarkers, Tumor; C061828:CD99 protein, human; D015815:Cell Adhesion Molecules; D007381:Intermediate Filament Proteins; C577484:NES protein, human; D009419:Nerve Tissue Proteins; D064231:Nestin; D014746:Vimentin; D019009:Proto-Oncogene Proteins c-kit