全身磁共振成像在多发性骨髓瘤诊断与临床分期中的价值

The Value of Whole-Body Magnetic Resonance Imaging in the Diagnosis and Staging System of Multiple Myeloma

目的：研究多发性骨髓瘤（MM）的全身磁共振成像（MRI）表现特点，探讨全身MRI参与临床分期的可能性。方法对45例初发的MM患者进行全身MRI检查，根据脊柱的MRI表现分型，分析MRI分型与骨髓活检瘤细胞所占百分比，将各型与临床分期对照，并以MRI表现参与Durie-Salmon（DS）分期。结果45例MM的MRI表现分为五型，其中正常型12例、弥漫型12例、局灶型7例、混合型8例和“盐和胡椒”型6例。正常型及“盐和胡椒”型平均骨髓瘤细胞百分比较低，分别为15.2%±3.5%和19.3%±4.3%，除2例“盐和胡椒”型外，均见于临床Ⅰ期；其余三型对应较高骨髓瘤细胞百分比，全部分布于Ⅱ期、Ⅲ期，其中弥漫型多见于Ⅲ期。与包含MRI表现的新分期方法相比，DS分期中总计有13例患者分期偏低。结论全身MRI分型有助于观察MM患者骨髓异常情况，其MRI表现与临床分期有一定相关性，将其表现加入DS分期可以显著提高对生存期预测的准确度。

Objective To determine the bone marrow infiltration of multiple myeloma （MM） with whole-body magnetic resonance imaging （MRI） in comparison with histopathological findings and clinical staging. To evaluate the prognostic value of a clinical staging system of whole body involvement using MRI in patients with MM. Methods 45 cases of newly diagnosed MM patients were studied with whole-body MRI. According to the type of spinal MRI findings, classification and analysis of whole-body MRI and bone marrow biopsy percentage of tumor cells were executed. With the control of various types with clinical stage, and MRI findings participated the Durie-Salmon （DS） staging. Results Five different infiltration patterns were described in MRI：a normal looking bone marrow signal was found in 12 patients, diffuse bone marrow infiltration in 12 patients, focal myeloma infiltration was found in 7 patients, a combined focal and diffuse infiltration pattern in 8 patients, and in 6 patients a so-called＆quot;salt-and-pepper＆quot;pattern. Percentage of normal type and＆quot;salt-and-pepper＆quot;type lower average myeloma cells were 15.2%±3.5%and 19.3%±4.3%, except for two cases of＆quot;salt-and-pepper＆quot;type, the other were seen in clinical stageⅠ. Compared to the other three types corresponding to a high percentage of tumor cells in bone marrow, all located in phase Ⅱ, phase Ⅲ, which diffused more common in phase Ⅲ.Compared with the new staging method including MRI manifestations, 13 cases in DS staging alone were less than new staging. Conclusion The whole-body MRI features can reveal bone marrow involvement of MM and may correlate to histology and clinical staging. A staging system of Durie and Salmon based on whole-body MRI provides a significant prognostic tool for patients with MM.