高级别表面骨肉瘤临床病理分析并文献复习

High-grade surface osteosarcoma: A clinicopathological analysis and literature review

目的:探讨高级别表面骨肉瘤(high-grade surface osteosarcoma,HGSO)的临床病理特征、诊断与鉴别诊断。方法:结合临床资料及影像学分析1例HGSO的形态特点并复习相关文献。结果:患者女性,17岁。以"发现右胫骨近段干骺部疼痛性肿块"入院。X线显示包块位于患骨皮质,呈云雾状矿化,伴针状骨膜反应及软组织肿块,其下骨皮质部分破坏或侵蚀,但髓腔完整。大体上肿瘤组织呈分叶状或隆起,软硬不一。镜下肿瘤细胞形成花边样骨样组织,细胞异质性及非典型性明显,核分裂活跃,表现为普通型骨肉瘤尤其骨母细胞型那样的组织学特点,但肿瘤附着于皮质,无或仅见轻度髓腔浸润。免疫组化示肿瘤细胞vimentin弥漫阳性,Ki-67高表达。尽管行截肢及术后辅助化疗,但36个月后患者死于肺转移。结论:HGSO是一种罕见的骨表面高度恶性肿瘤,预后不佳。熟悉其组织学特点有助于正确诊断。

Objective： To investigate the clinicopathologic features,diagnosis and differential diagnosis of high-grade surface osteosarcoma（ HGSO）. Methods： One case of HGSO was analysed morphologically in combination with clinical data and image findings. And the existing literature was reviewed. Results： The patient was a 17-year-old girl who was admitted to the hospital for a boring and sever painful/tender mass found close to the metaphysic of her proximal tibia. X-ray revealed a fluffy mineralized lesion with needle-like periosteal reaction and soft-tissue mass which situated on the surface of the affected bone. The underlying cortex was partially destroyed or eroded. Yet the medullar cavity remained intact. Grossly,the tumor was depicted as multilobulated or bulky appearance with a mixture of fleshy and hard area. Microscopically,based on the lace-like osteoid production,the tumor cells had marked heterogeneous/atypical with brisk mitotic activity. The pathologic features of HGSO displayed as the same of conventional osteosarcoma,especially the osteoblastic subtype,however,the tumor was attached on the cortex only and presented with no or,sometimes,minimal medullar cavity involvement. Immunohistochemically,the tumor cells were positive for vimentin. Meanwhile,it expressed Ki-67 in a high level. After ablative surgery 36 months and combination of post-operative adjuvant chemotherapy,the patient died of pulmonary metastasis despite amputation was performed. Conclusion： HGSO is a rare malignant bone-forming neoplasm that arises from the surface of the bone with high-grade cytological features and poor prognosis. Familiarity with its histologic characteristics is helpful to making correct diagnosis.