长骨骨干骨肉瘤的影像学表现探讨

目的：分析长骨骨干骨肉瘤X线、CT和MRI表现,探讨有关的临床特点和鉴别诊断。方法：28例长骨骨干骨肉瘤患者,均经手术与病理证实,其中病变位于股骨干18例、腓骨干4例、肱骨干4例、胫骨干2例。所有患者均行X线、CT和MRI检查,对其影像学表现与手术病理结果进行对照,并由双盲法分析确认。结果：28例中,X线和CT显示广泛骨质破坏16例,骨膜反应22例。X线显示软组织肿块18例,肿瘤骨和瘤样钙化12例。CT平扫显示软组织肿块22例,增强扫描显示软组织肿块24例,肿瘤骨和瘤样钙化16例。MRI显示骨质破坏和骨膜反应10例,软组织肿块26例,其周围可见软组织水肿及骨髓水肿。骨膜反应在SE T1WI上呈等低信号,T2WI呈等信号。软组织肿块在T1W1为等信号,T2WI及STIR呈等高信号。软组织水肿及骨髓水肿在T2Wl及STIR呈高信号。MRI增强检查显示病灶均呈不均匀强化,骨髓水肿和软组织肿块均见强化。结论：X线、CT和MRI从不同方面反映长骨骨干骨肉瘤的影像病理特点,其发病率低,骨破坏范围大,无病理性骨折。成骨型骨干骨肉瘤较易诊断,溶骨型应与Ewing瘤、恶性巨细胞瘤等鉴别。

Imaging Features of Long-bone Osteosarcoma

Objective:To analyze the imaging features of long-bone osteosarcoma of X-ray,computed tomography(CT),and magnetic resonance image(MRI) in order to summarize the clinical characteristics and provide differential diagnosis of long-bone osteosarcoma.Methods: A total of 28 patients with long-bone osteosarcoma were all confirmed by pathological examination.The distribution was as follows: 18 in the femoral shaft,4 in the fibular shaft,4 in the humeral shaft,and 2 in the tibial shaft.The information gathered from X-ray,CT,and MRI was analyzed and compared to pathological examination in a double-blind way.Results: Among the 28 patients,X-ray and CT showed extensive bone destruction in 16 cases and periosteal reaction in 22 cases.X-ray showed 18 cases of soft tissue mass,and 12 of neoplastic bone and tumor calcification.Normal CT scan reported 22 cases of soft tissue mass.While with enhanced CT scan,there were 24 cases of soft tissue mass and 16 cases of neoplastic bone and tumor calcification.With MRI scan,10 cases were reported to present bone destruction and periosteal reaction,and 26 to present soft tissue mass,around which there were soft tissue and bone marrow swelling.On T1-weighted images,MRI showed low signal intensity of periosteal reaction and equal signal intensity of the soft tissue mass.On T2-weighted and STIR images,MRI showed equal signal intensity of periosteal reaction and high signal intensity of soft tissue swelling and bone marrow swelling.Uneven enhancement was observed at the diseased sites with enhanced MRI examination.There was enhancement both in the bone marrow swelling and soft tissue mass.Conclusion: X-ray,CT and MRI can reflect the imaging features of long-bone osteosarcoma from different aspects.Osteosarcoma has low incidence,with large area of bone destruction,but it has no pathological fractures.It is easier to diagnose long-bone osteosarcoma of ossification.Osteolytic osteosarcoma should be distinguished from Ewing sarcoma,malignant giant cell tumor and so on.