Forcucci Jessica A, Sugianto Jessica Z, Wolff Daynna J, Maize John C, Ralston Jonathan S
Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC.
Am J Dermatopathol. 2015 Dec;37(12):920-3. doi: 10.1097/DAD.0000000000000286.
Spindle cell and pleomorphic lipoma constitute a spectrum of lipomatous lesions with characteristic clinical, morphologic, immunohistochemical, and molecular features. Multiple variants have been previously described including vascular, fibrous, plexiform, and those with significantly less fat termed "low-fat" and "fat-free" by Folpe. Cytogenetically, spindle cell lipomas frequently display monoallelic loss of 13q14 region, an abnormality also found in cellular angiofibroma and mammary-type myofibroblastoma. Pseudoangiomatous spindle cell lipoma, originally described by Fletcher et al in 1994, is a rare variant within the spindle cell/pleomorphic lipoma spectrum, with less than 20 published cases. It consists of an admixture of spindle cells, "ropey" collagen, variable amounts of mature fat, and irregular, branching slit-like vascular spaces. The authors present a case of a 1-cm subcutaneous lesion excised from the neck of a 70-year-old man with classic histologic and immunohistochemical features of "low-fat" pseudoangiomatous spindle cell lipoma. Fluorescence in situ hybridization demonstrated a loss of 13q14 region, a characteristic presumed cytogenetic finding of spindle cell lipoma, which has been previously unconfirmed in this variant.
梭形细胞脂肪瘤和多形性脂肪瘤构成了一系列具有特征性临床、形态学、免疫组化和分子特征的脂肪瘤性病变。先前已描述了多种变体，包括血管性、纤维性、丛状性，以及那些脂肪含量明显较少的，Folpe将其称为“低脂”和“无脂”型。细胞遗传学上，梭形细胞脂肪瘤常显示13q14区域的单等位基因缺失，这种异常也见于细胞性血管纤维瘤和乳腺型肌成纤维细胞瘤。假性血管瘤样梭形细胞脂肪瘤最初由Fletcher等人于1994年描述，是梭形细胞/多形性脂肪瘤谱系中的一种罕见变体，已发表病例少于20例。它由梭形细胞、“索状”胶原、不同数量的成熟脂肪和不规则分支的裂隙状血管腔混合而成。作者报告了一例从一名70岁男性颈部切除的1厘米皮下病变，具有“低脂”假性血管瘤样梭形细胞脂肪瘤的典型组织学和免疫组化特征。荧光原位杂交显示13q14区域缺失，这是梭形细胞脂肪瘤的一种假定细胞遗传学特征，此前在该变体中尚未得到证实。
