黏液炎症性纤维母细胞肉瘤临床病理特点

Clinicopathological characteristics of myxoinflammatory fibroblastic sarcoma

目的探讨黏液炎症性纤维母细胞肉瘤（MIFS）的临床病理学特征、免疫学表型及鉴别诊断。方法对2例四肢的MIFS进行光镜观察和免疫组化标记,并文献复习。结果MIFS可发生于任何年龄段,多发于40～50岁,肿块位于肢端皮下组织,境界不清,生长缓慢,偶伴疼痛。镜检：病变呈多结节状,玻璃样和黏液样间质相间的背景中有大量急慢性炎症细胞浸润。病变中肿瘤细胞呈3种典型形态：梭形细胞、神经节样细胞或RS细胞样细胞和脂母细胞样细胞。免疫组化：瘤细胞vimentin、CD34弥漫（＋）,CD68和Mac387灶性（＋）,SMA、CK、HHF-35、S-100、CD30和CD15均（-）。结论MIFS是一种罕见的低度恶性软组织肉瘤,瘤细胞由变异的纤维母细胞衍化而来。该瘤在局部呈侵袭性生长,具有较高的复发率,偶有转移。推荐局部扩大切除治疗。

Objective To study the clinical pathological features, immunophenotype and differential diagnosis of myxoinflammatory fibroblastic sarcoma （MIFS）. Methods Two cases of MIFS were investigated by microscopy, immunohistochemistry and literature review. Results Clinically, MIFS occurred in patients of all age, with a peak incidence in the fourth and fifth decade. It typically presented an ill defined and slowly growing mass of the distal extremities within the subcutaneous tissues, sometime with pain. Microscopically, the lesions were multinodular, and characterized by a myxohyaline stroma containing numemns inflammatory ceils. Amidst the inflammatory background there were scattered with spindle-shaped cells, ganglion or Reed-Sternberg-like ceils and multivacuolated lipoblast-like cells. Immunohistochemically, the fibroblast was strongly positive for vimentin and CD34, focal positive for CD68 and Mac387, negative for SMA, CK, HHF-35, S-100, CD30 and CD15. Conclusion MIFS is an extremely rare sarcoma of soft tissue, and the tumor ceils may derive from modified fibroblast. The tumor has a locally invasive growth potential, with a high rate of recurrence and rare metastasis. Local excision is recommended for the treatment of this tumor.