去分化软骨肉瘤的临床病理诊断

目的 探讨去分化软骨肉瘤的临床、影像和病理学特征及鉴别诊断.方法 收集并分析去分化软骨肉瘤14例的临床及影像学资料,通过光镜观察及免疫组织化学EnVision法(抗体包括波形蛋白、S-100蛋白、平滑肌肌动蛋白、KP-1、PGM-1)分析其病理学特征、免疫表型及鉴别诊断.结果 14例去分化软骨肉瘤平均年龄52岁,男女比9:5.好发部位与普通软骨肉瘤一致,即盆三角、肩三角、肋骨和膝关节上下.影像学表现为双重形态特征的恶性肿瘤.大体中央型多于周围型,组织学由分界清楚的高分化软骨性肿瘤和高级别间变性肉瘤构成.术前单点穿刺活检漏诊、误诊率高.肿瘤内间变性肉瘤成分按发生率高低依次为骨肉瘤、恶性纤维组织细胞瘤和纤维肉瘤.结论 去分化软骨肉瘤为软骨肉瘤的少见特殊类型,具有与普通软骨肉瘤和软骨母细胞型骨肉瘤不同的临床、影像学和病理学特征,预后很差.

Clinicopathologic diagnosis of de-differentiated chondrosarcoma

Objective To study the clinicopathologic and radiologic features of dedifferentiated chondrosarcoma, focusing on its diagnosis and differential diagnosis. Method Clinical, radiological and pathologic findings of 14 cases of dedifferentiated chondrosarcoma ( including biopsy and surgical specimens) were analyzed by hematoxylin and eosin stained sections and immunohistochemistry. Results The mean age of patients was 52 years. The male-to-female ratio was 9:5. The most common sites of involvement were pelvis , femur and humerus, similar to the conventional chondrosarcoma. Radiologically, they were malignant tumors with dimorphic pattern. Grossly, central chondrosarcomas were more common than those of the peripheral. An essential histological feature of dedifferentiated chondrosarcoma was an abrupt interface between the low-grade cartilaginous tumor and high-grade anaplastic sarcoma. The most common dedifferentiated components were osteosarcoma, malignant fibrous histocytoma and fibrosarcoma. False negative diagnosis and erroneous diagnosis were frequent when only one-time biopsy was available. Conclusions Dedifferentiated chondrosarcoma is a rare subtype of chondrosarcoma with poor prognosis, which has different features of clinical manifestation, imaging features and pathological characteristics, compared to conventional chondrosarcoma and chondroblastic osteosarcoma.