Fons Mark E, Bachhuber Thomas, Plaza Jose A
Department of Dermatopathology, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
J Cutan Pathol. 2011 Jan;38(1):49-53. doi: 10.1111/j.1600-0560.2009.01420.x.
A case of cutaneous leiomyosarcoma originating in a symplastic pilar leiomyoma is described. The patient was a 60-year-old man who presented with a painless nodule on his chest. Thorough clinical examination did not reveal any evidence of tumor elsewhere. A punch biopsy was performed which showed a benign spindle cell neoplasm with focal cellular pleomorphism that had smooth muscle differentiation and was clearly originating from the arrector pili muscle, consistent with a cutaneous symplastic pilar leiomyoma. Immunohistochemical studies were performed and the tumor cells were strongly positive for smooth muscle actin (SMA) and desmin. Given the clinical information of a mass on the chest, clinical evaluation was recommended and a re-excision was performed. Histologically, the re-excision showed two distinct populations of cells. The upper portion of the tumor mirrored the initial biopsy; however, the base of the tumor showed hypercellular areas composed of spindle cells with marked pleomorphism and increased number of mitoses. The diagnosis of a cutaneous leiomyosarcoma originating in a symplastic pilar leiomyoma was given. This is the first report of this association of such occurrence reported in the literature.
本文描述了一例起源于增生性毛囊平滑肌瘤的皮肤平滑肌肉瘤病例。患者为一名60岁男性，胸部出现无痛性结节。全面的临床检查未发现其他部位有肿瘤迹象。进行了打孔活检，结果显示为良性梭形细胞瘤，具有局灶性细胞多形性，有平滑肌分化，且明确起源于立毛肌，符合皮肤增生性毛囊平滑肌瘤。进行了免疫组织化学研究，肿瘤细胞平滑肌肌动蛋白（SMA）和结蛋白呈强阳性。鉴于胸部肿物的临床信息，建议进行临床评估并再次切除。组织学检查显示，再次切除的标本中有两种不同类型的细胞。肿瘤上部与最初活检结果相似；然而，肿瘤底部显示为细胞增多区域，由具有明显多形性的梭形细胞组成，有丝分裂数量增加。诊断为起源于增生性毛囊平滑肌瘤的皮肤平滑肌肉瘤。这是文献中首次报道这种关联的此类病例。
