Application Value Of Whole-body Diffusion Weighted Imaging For The Assessment Of Bone Marrow Involvement And The Chemotherapy Response Evaluation In Malignant Lymphoma Patients

Part 1 A comparative study of combining whole body diffusion weighted imaging with whole body T2-weighted imaging and PET/CT for the detection of bone marrow involvement in malignant lymphoma patientsObjective:To compare the clinical value of combining WB-DWI with whole body T2WI and PET/CT for the diagnosis of bone marrow involvement in malignant lymphoma patients.Materials and methods:61 Patients with newly diagnosed,pathologically proven malignant lymphoma between August 2017 and December 2018 who underwent WB-DWI,T2WI,PET/CT and bone marrow biopsy were included in this prospective study.Bone marrow biopsy is the gold standard for bone marrow assessment.The type and location of lymphoma bone marrow infiltration were observed,and the diagnostic efficacy of the two imaging methods for bone marrow infiltration was calculated and compared.Results:The diagnostic sensitivity,specificity,accuracy,positive predictive value,negative predictive value and the area under receiver operating characteristic curve(ROC)of combining WB-DWI with whole body T2WI for the diagnosis of-bone marrow involvement in malignant lymphoma patients were 87.5%,93.3%,91.8%,82.4%,95.5%and 0.873,respectively.For PET/CT,they were 81.3%,91.1%,88.5,76.5%,93.2%and 0.819,respectively.The consistency between the two imaging methods and the results of bone marrow biopsy was good.And there was no significant difference in the diagnostic sensitivity,specificity,accuracy,positive predictive value,negative predictive value and the area under ROC curves between the two imaging methods(P>0.05).Conclusion:Both combining WB-DWI with whole body T2WI and PET/CT have good performance for the diagnosis of lymphoma bone marrow involvement.There is no significant difference between the results of two imaging methods for the assessment of bone marrow involvement in lymphoma patients,and the diagnostic value of the two methods is equal.Part 2 Application research of whole-body diffusion weighted imaging and apparent diffusion coefficient for the chemotherapy response evaluation of lymph node in malignant lymphoma patientsObjective:To investigate the application value of whole-body diffusion weighted imaging and apparent diffusion coefficient for the chemotherapy response evaluation of lymph nodes in malignant lymphoma patients.Materials and methods:18 Patients with newly diagnosed,pathologically proven malignant lymphoma between August 2017 and December 2018 who underwent WB-DWI before chemotherapy and after three courses chemotherapy were included in this prospective study.Another 10 healthy volunteers were selected for WB-DWI examination as the control group.ADC values of the same lesions in lymphoma patients were measured on ADC maps before chemotherapy and after the third course of chemotherapy,respectively.ADC values of healthy volunteers were measured in small axillary lymph nodes.Statistical analysis was performed on the difference of ADC values of lymph nodes in lymphoma patients before and after chemotherapy,and the difference was compared with that of healthy volunteers.Results:The mean ADC value of lymph nodes in malignant lynphoma patients before chemotherapy was 0.86 × 10-3 mm2/s,and the ADC value after the third course of chemotherapy was 1.84×10-3 mm2/s.The mean ADC value of small axillary lymph nodes in healthy volunteers was 2.19×10-3 mm2/s.There was a significant difference in ADC value of lymph nodes in malignant lymphoma patients before chemotherapy and after the third course of chemotherapy(t=-15.09,P<0.01).The difference between mean ADC value of lymph nodes in malignant lymphoma patients before chemotherapy and that of healthy volunteers was statistically significant(t=-14.159,P<0.01).And there was significant difference between ADC value of lymph nodes in malignant lymphoma patients after the third course of chemotherapy and that of healthy volunteers(t=-2.359,P=0.026).Conclusion:WB-DWI and quantitative analysis of ADC value have good clinical application value in monitoring the efficacy of chemotherapy in malignant lymphoma patients.