Ruiz-Arriaga Leon Felipe, Ramirez Teran Ana Laura, Ortiz-Hidalgo Carlos, Fonte-Avalos Veronica, Toussaint-Caire Sonia, Vega-Memije Ma Elisa, Anda-Juarez Mariana CatalinaDe
Department of Dermatopathology,'Dr. Manuel Gea Gonzalez' General Hospital, Mexico City.
Dermatol Online J. 2018 Apr 15;24(4):13030/qt5z02t0dk.
Myopericytoma is a soft-tissue tumor of perivascular cells (pericytes). It is slow-growing, usually asymptomatic, and generally benign, although a malignant variant has been described. The etiology is unknown, but it has been associated with local trauma. The most common location is on the distal extremities. Histologically, it is characterized by a well-circumscribed, non-encapsulated proliferation of spindle shaped cells similar to myofibroblasts with oval nuclei and eosinophilic cytoplasm, arranged in perivascular concentric rings. There are few mitoses and no necrosis is reported. The immunohistochemical analysis is positive for smooth muscle actin and negative or weakly positive for desmin. A low Ki-67 proliferation index is typical. Treatment is surgical excision with free margins. Recurrences after adequate excision are uncommon. We describe a 48-year-old woman with a myopericytoma in an unusual location (next to the inner corner of her left eye) who was treated with surgical excision; there has been no recurrence after 5 years of follow up.
肌周细胞瘤是一种血管周围细胞（周细胞）的软组织肿瘤。它生长缓慢，通常无症状，一般为良性，不过也有恶性变体的报道。病因不明，但与局部创伤有关。最常见的部位是四肢远端。组织学上，其特征是由梭形细胞构成的边界清楚、无包膜的增生，这些细胞类似于肌成纤维细胞，具有椭圆形细胞核和嗜酸性细胞质，呈血管周围同心圆状排列。有少数核分裂象，未报告有坏死。免疫组织化学分析显示平滑肌肌动蛋白呈阳性，结蛋白呈阴性或弱阳性。典型的Ki-67增殖指数较低。治疗方法是进行切缘阴性的手术切除。充分切除后复发并不常见。我们描述了一名48岁女性，其肌周细胞瘤位于一个不寻常的位置（左眼角内侧旁），接受了手术切除治疗；随访5年后未复发。
