Based on the morphologic and immunohistochemical findings, the following histotypes were identified: (i) tumors (10/19 cases) with the characteristic morphology of myofibroblastoma and stained with vimentin, CD34, desmin, and α-smooth muscle actin; (ii) fibroblastic benign spindle cell tumors (5/19 cases) composed of fibroblast-like cells stained only with vimentin and CD34; (iii) tumors (2/19 cases) with the typical morphologic features of solitary fibrous tumor and stained with vimentin, CD34, and STAT6; (iv) 1 case of spindle cell lipoma stained with vimentin and CD34; and (v) 1 case of fibroma composed of a paucicellular, diffusely hyalinized stroma with expression of vimentin and CD34.
The adjacent deep preaponeurotic fat displayed nodules of collagen with myxoid change and occasional CD34 spindle cells suggestive of a spindle cell lipoma.
An analysis of the literature reveals that although CD34 immunoreactivity is characteristic of spindle cell lipoma and helps exclude nonlipomatous neoplasms, it does not clearly eliminate other well-differentiated lipomatous tumors.
Molecular Signature of Tumors with Monoallelic 13q14 Deletion: a Case Series of Spindle Cell Lipoma and Genetically-Related Tumors Demonstrating a Link Between FOXO1 Status and p38 MAPK Pathway.
Genetic information on pseudoangiomatous pleomorphic/spindle cell lipoma is restricted to a single case in which deletion of the forkhead box O1 (FOXO1) gene was found, using fluorescence in situ hybridization (FISH).
S-100-expression in spindle cell lipoma may cause problems in the differential diagnosis with neural and melanocytic neoplasms and emphasizes the plasticity of the spindle cells in spindle cell lipoma.
S-100-expression in spindle cell lipoma may cause problems in the differential diagnosis with neural and melanocytic neoplasms and emphasizes the plasticity of the spindle cells in spindle cell lipoma.
Based on the morphologic and immunohistochemical findings, the following histotypes were identified: (i) tumors (10/19 cases) with the characteristic morphology of myofibroblastoma and stained with vimentin, CD34, desmin, and α-smooth muscle actin; (ii) fibroblastic benign spindle cell tumors (5/19 cases) composed of fibroblast-like cells stained only with vimentin and CD34; (iii) tumors (2/19 cases) with the typical morphologic features of solitary fibrous tumor and stained with vimentin, CD34, and STAT6; (iv) 1 case of spindle cell lipoma stained with vimentin and CD34; and (v) 1 case of fibroma composed of a paucicellular, diffusely hyalinized stroma with expression of vimentin and CD34.
Based on the morphologic and immunohistochemical findings, the following histotypes were identified: (i) tumors (10/19 cases) with the characteristic morphology of myofibroblastoma and stained with vimentin, CD34, desmin, and α-smooth muscle actin; (ii) fibroblastic benign spindle cell tumors (5/19 cases) composed of fibroblast-like cells stained only with vimentin and CD34; (iii) tumors (2/19 cases) with the typical morphologic features of solitary fibrous tumor and stained with vimentin, CD34, and STAT6; (iv) 1 case of spindle cell lipoma stained with vimentin and CD34; and (v) 1 case of fibroma composed of a paucicellular, diffusely hyalinized stroma with expression of vimentin and CD34.
Based on the morphologic and immunohistochemical findings, the following histotypes were identified: (i) tumors (10/19 cases) with the characteristic morphology of myofibroblastoma and stained with vimentin, CD34, desmin, and α-smooth muscle actin; (ii) fibroblastic benign spindle cell tumors (5/19 cases) composed of fibroblast-like cells stained only with vimentin and CD34; (iii) tumors (2/19 cases) with the typical morphologic features of solitary fibrous tumor and stained with vimentin, CD34, and STAT6; (iv) 1 case of spindle cell lipoma stained with vimentin and CD34; and (v) 1 case of fibroma composed of a paucicellular, diffusely hyalinized stroma with expression of vimentin and CD34.
Of the initial 25 cases identified, comparative genomic hybridization (CGH) was uninformative in 2 cases; 5 were reclassified as WDL on the basis of molecular data (MDM2 amplification) and 6 as spindle cell lipoma (CGH profiles with a few gains and losses including a constant loss of chromosome 13 and frequent losses of chromosomes 16 and 6).