脊柱外骨孤立性浆细胞瘤的影像表现及误诊分析

摘要

Objective To assess the imaging features of solitary extra-spinal plasmacytoma. Methods The imaging studies of 22 patients with histologically confirmed solitary extra -spinal plasmacytomas were retrospectively analyzed. .Results On radiographs and CT , the lesions were expansile and lytic with well-defined margins , cortical thinning or erosion , no calcification or sclerotic rim..Residual bone trabecula was present in 11 patients whereas irregular periosteal reaction was found in only 1 patient. On MRI,.14 tumors were slightly T1 and T2 hyperintense relative to muscle or brain with homogenous enhancement and no necrosis. The lesions showed an infiltrative growth pattern. Associated soft-tissue mass was noted in 2 and peritumoral marrow edema in none. 63.6% (14/22) of the tumors were misdiagnosed as lymphomas (5), giant cell tumors (4), fibrosarcomas (2), metastases (2) and chordoma (1). Conclusion Most of the solitary extraspinal plasmacytomas have some specific imaging features , especially on MRI. However, differentiation from primary and secondary bone tumors may be difficult.%目的：探讨脊柱外骨孤立性浆细胞瘤（SPB）的影像学特点，提高影像诊断水平。方法搜集经手术病理证实的22例脊柱外SPB患者的术前影像资料，回顾性分析其X 线、CT、MRI表现以及误诊原因。结果22例脊柱外 SPB X 线及CT表现为膨胀性、溶骨性骨质破坏，边界较清，边缘见弧形压迹，骨皮质变薄、中断，无硬化边或钙化；11例病灶可见骨嵴从边缘向中心延伸；1例见不规则骨膜反应，其余病灶未见明显骨膜反应。MRI显示14例病灶呈稍短T1、稍长T2信号，增强明显强化；肿瘤局部突破骨皮质向外侵犯，呈“伪足征”；2例病灶周围形成软组织肿块；无瘤周骨髓水肿。14例术前影像学检查报告误诊，其中误诊为淋巴瘤5例，骨巨细胞瘤4例，纤维肉瘤2例，转移瘤2例，脊索瘤1例。结论脊柱外SPB的影像表现有一定特征，其MRI信号特点在SPB的诊断及鉴别诊断中有重要价值，但仍需与骨淋巴瘤、单发转移瘤相鉴别。