伴破骨样巨细胞平滑肌肉瘤的临床病理学观察

目的 探讨伴破骨样巨细胞平滑肌肉瘤的临床病理学特点及其鉴别诊断.方法 收集7例伴大量破骨样巨细胞平滑肌肉瘤病例的临床和影像学资料,行光镜观察、免疫组织化学(EnVision法)标记和电镜观察,并复习相关文献.结果 患者均为成年人,其中女性3例,男性4例,平均年龄 63岁.肿瘤位于大腿皮下软组织2例,左背部、腹膜后、小肠、乳腺和子宫各1例.组织学上,所有病例均由形态相对一致、呈交织条束状排列的梭形瘤细胞和大量的破骨样巨细胞组成,后者多散在分布于梭形细胞之间(6例),或形成巨细胞瘤样结节(1例).免疫组织化学标记显示,梭形细胞程度不等地表达平滑肌肌动蛋白、肌特异性肌动蛋白、结蛋白和高相对分子质量钙调结合蛋白,破骨样巨细胞表达CD68.电镜观察显示梭形细胞具平滑肌分化特征,破骨样巨细胞则具组织细胞分化.随访6例患者,均在术后发生复发或转移,其中3例带瘤生存,2例死亡.结论 (1)伴大量破骨样巨细胞的平滑肌肉瘤是平滑肌肉瘤的一种少见亚型,形态上与巨细胞型恶性纤维组织细胞瘤相似,诊断时应注意加以鉴别.(2)免疫组织化学标记和电镜观察提示肿瘤内的破骨样巨细胞起源于单核细胞/组织细胞系.(3)该肿瘤的恶性程度高,预后差.

Abstract：

Objective To study the clinicopathologic features of leiomyosarcoma with prominent osteoclast-like giant cells. Methods The clinical and pathologic features of 7 cases of leiomyosarcoma with prominent osteoclast-like giant cells were analyzed. Immunohistochemical and ultrastructural studies were performed. The literature was reviewed. Results All cases occurred in adults, with a mean age of 63 years. There was no significant soft tissue of thigh (number=2), left back (number=1), retroperitoneum (number=1), small intestine (number=1), breast (number=1) and uterus (number=1). Histologic examination showed that the tumor was composed of relatively uniform spindly cells arranged in interlacing fascicles. The hallmark was the presence of prominent osteoclast-like giant cells, either intimately admixed with the spindly cells (number=6) or forming giant cell tumor-like nodules (number=1). Immunohistochemically, the spindly cells expressed smooth muscle actin, muscle-specific actin, desmin and h-caldesmon in various degrees, whereas the osteoclast-like giant cells expressed CD68. Ultrastructural study showed smooth muscle differentiation in the spindly cells and histiocytic differentiation in the osteoclast-like giant cells. Follow-up data were available in 6 cases. There were local recurrences and/or metastases in all the 6 patients. Three patients were alive with unresectable or recurrent/metastatic disease and two patients died of the disease. Conclusions Leiomyosarcoma with prominent osteoclast-like giant cells is a rare variant of leiomyosarcoma which should be distinguished from the so-called giant cell variant of malignant fibrous histiocytoma. The osteoclast-like giant cells are of histiocytic differentiation. Surgical resection remains the mainstay of management of this high-grade sarcoma.

Leiomyosarcoma with prominent osteoclast-like giant cells: a clinicopathologic analysis of 7 cases and review of literature

Objective To study the clinicopathologic features of leiomyosarcoma with prominent osteoclast-like giant cells. Methods The clinical and pathologic features of 7 cases of leiomyosarcoma with prominent osteoclast-like giant cells were analyzed. Immunohistochemical and ultrastructural studies were performed. The literature was reviewed. Results All cases occurred in adults, with a mean age of 63 years. There was no significant soft tissue of thigh (number=2), left back (number=1), retroperitoneum (number=1), small intestine (number=1), breast (number=1) and uterus (number=1). Histologic examination showed that the tumor was composed of relatively uniform spindly cells arranged in interlacing fascicles. The hallmark was the presence of prominent osteoclast-like giant cells, either intimately admixed with the spindly cells (number=6) or forming giant cell tumor-like nodules (number=1). Immunohistochemically, the spindly cells expressed smooth muscle actin, muscle-specific actin, desmin and h-caldesmon in various degrees, whereas the osteoclast-like giant cells expressed CD68. Ultrastructural study showed smooth muscle differentiation in the spindly cells and histiocytic differentiation in the osteoclast-like giant cells. Follow-up data were available in 6 cases. There were local recurrences and/or metastases in all the 6 patients. Three patients were alive with unresectable or recurrent/metastatic disease and two patients died of the disease. Conclusions Leiomyosarcoma with prominent osteoclast-like giant cells is a rare variant of leiomyosarcoma which should be distinguished from the so-called giant cell variant of malignant fibrous histiocytoma. The osteoclast-like giant cells are of histiocytic differentiation. Surgical resection remains the mainstay of management of this high-grade sarcoma.