Musculoskeletal Tumors:Evaluation Of Three Dimensional Arterial Spin Labeling Perfusion Imaging And Biexponenrial Multiple B Values Diffusion Weighted Imaging And With Results Of Pathological Investigation

Objectives:1. To evaluate the value of magnetic resonance three dimensional arterial spin labeling (3D-ASL) perfusion imaging and biexponential multiple b values diffusion weighted imaging (Mb DWI) in differential diagnosis and quantitative analysis of musculoskeletal tumors.2. To study the relationship between pathologic indicators of angiogenesis including microvessel density and biological behaviour of tumors.3. To analyze the correlation of quantitative parameters of MRI, including TBF, standard ADC, fast ADC, and slow ADC with MVD.Materials and MethodsRoutine MRI,3D-ASL, biexponential Mb DWI, surgeon and pathological investigation were performed on forty patients with musculoskeletal tumors. TBF, standard ADC, slow ADC, fast ADC were measured in regions of interest after post-processing for3D-ASL and Mb DWI. Immunohistochemical staining of specimens was performed by using CD34monoclonal antibody to calculate MVD counts.MVD, TBF, standard ADC, fast ADC, and slow ADC of different groups were compared by independent sample t test.ROC curve was used to analysis ASL and Mb DWI, in order to determine the threshold and diagnostic reliability. The correlation between quantitative parameters of MRI,including TBF, standard ADC, fast ADC, slow ADC and MVD counts were evaluated using correlative analysis.Results1. All the pathology was comfirmed by biopsy or postoperative specimens.There were11benign tumors,8intermediate tumors and21malignant tumors.2. MVD counts:CD34of40cases reveal positive.The average MVD was10.05±4.66in the benign group,13.06±5.73in the intermediate group, and33.47±.66in the malignant group.There were significant differences of MVD among benign, intermediate and malignant group.There was significant difference of MVD between benign and malignant group, as well as intermediate and malignant group.There was no significant difference of MVD between benign and intermediate group.3. ASL:TBF was29.47±10.79ml/min/100g in benign group,26.96±9.91ml/min/100g in intermediate group, and82.95±29.47ml/min/100g in malignant group. There was significant difference of TBF between benign and malignant group,as well as intermediate and malignant group.There was no significant difference of TBF between benign and malignant group.According to the ROC analysis,area under curve was largest at0.956when consider45.5ml/min/100g as threshold of TBF in diagnosing. The diagnostic sensitivity and specificity are90.5%and100%correspondingly. 4. Mb DWI:Standard ADC, solw ADC, fast ADC of benign group were0.00402±0.00706mm2/s,0.00183±0.000471mm2/s and0.0107±0.00453mm2/s respectively. Standard ADC, solw ADC, fast ADC of intermediate group were0.00109±0.000469mm2/s0.00149±0.000667mm2/s and0.00675±0.00145mm2/s respectively. Standard ADC, solw ADC, fast ADC of malignant group are0.00115±0.000403mm2/s,0.00139±0.000614mm2/s and0.0167±0.00576mm2/s respectively.There was no significant difference of standard ADC, solw ADC and fast ADC between benign and intermediate group. There was no significant difference of standard ADC between benign and malignant group. There was significant difference of solw ADC and fast ADC between benign and malignant group (p<0.05). There was no significant difference of standard ADC and solw ADC between benign and intermediate group. There was significant difference of fast ADC between benign and intermediate group (p<0.05). According to the ROC analysis, area under curve was largest at0.871when consider0.011mm2/s as threshold of fast ADC in diagnosing. The diagnostic sensitivity and specificity are90.5%and78.9%correspondingly.5. Correlation between TBF, standard ADC, fast ADC, slow ADC and MVD: There was a significant positive correlation between TBF and MVD (r=0.784, p=0.000), as well as correlation between TBF and fast ADC(r=0.727, p=0.000).There was a moderate positive correlation between fast ADC and MVD (r=0.516, p=0.000). There were no significant correlation between slow ADC and MVD as well as correlation between standard ADC and MVD.Conclusion:1. The MVD represent the angiogenesis of musculoskeletal tumors, reflecting biological behavior of the tumor.2.3D-ASL and Mb DWI are valuable in differentiating benign from malignant musculoskeletal tumors. 3. ASL and biexponential Mb DWI can be used for evaluating the angiogenesis of musculoskeletal tumors and the blood flow of the tissue by reflecting MVD of musculoskeletal tumors as a completely noninvasive technique.Therefore they can detect the microcosmic structure of musculoskeletal tumors in vivo by noninvasive methods safely and rapidly.