Preliminary Study Diagnostic Value Of Diffusion Imaging ADC Histogram In Differentiating Prostate Cancer From Benign Prostatic Hyperplasia And Correlation With Gleason Scores

ObjectiveThis prospective study of prostate cancer and benign prostatic hyperplasia patients with MR diffusion weighted imaging（DWI）,were used to obtain apparent diffusion coefficient（ADC）histogram（ADC histogram）and histogram feature parameters from the lesion 3D volume,investigate the value of 3D ADC histogram and its characteristic parameter in the differentiation of prostate cancer and benign prostatic hyperplasia,and its correlation with Gleason score of prostate cancer are analyzed.Materials and methodsProspective analysis of March 2015 to February 2017 in the First Affiliated Hospital of Guangzhou Medical University Hospital and confirmed by biopsy or prostate lesions were confirmed by pathology in 66 cases,including prostate hyperplasia group（BPH group）33 patients,aged 46 to 80 years old,TPSA is1.03ng/ml⁷2.51ng/ml;prostate cancer group（PCa group）33 cases,age 52 to 84years old,TPSA 2.25ng/ml⁶11ng/ml.This group of 33 cases of Pca,according to the scores of Gleason were divided into 2 groups:20 cases of PCa Gleason score was 6 to 7,as in the differentiation group,aged 52 to 84 years old,TPSA 5.41ng/ml to 540.1ng/ml,13 cases;PCa Gleason score of 8 to 10,belong to low differentiation,age 62⁸2 years old TPSA,2.25ng/ml⁶11ng/ml.All the patients before treatment underwent routine MRI scanning and transverse（spin echo echo planar imaging,Spin Echo-Echo Planar Imaging,SE-EPI）DWI b=0,1500 s/mm2.sequence scan of the original DWI image of all patients on Philips workstation for postprocessing ADC map.The ADC map import to（Omin-Kinetics,OK）software provided by the GE company,according the size and location of lesions in sequence of T2WI,on ADC map layer hand draw focus on all levels and regions of interest ROI（to avoid cystic necrosis,hemorrhage and calcification area）.OK software to automatically calculate the ADC value of lesions in 3D histogram and its corresponding parameter value according to the multi level hand painted ROI,including the average number of ADC（ADCmean）,the median of ADC（ADCmedian）,ADC percentile（ADC10th,ADC25th,ADC50th,ADC75th,ADC90th）,ADC value histogram skewness and kurtosis;At the same time,the ADC value of the maximum level of ROI measured in all patients was recorded as 2D ADC value.The differences of T1WI,T2WI and DWI signal features between the PCa group and BPH group was analyzed by Fisher exact test.Using two independent samples t test were compared differentiation of2D ADC value between the PCa group and BPH group,as well as between the PCa low differentiation group and moderate differentiation group.Using two independent samples t test were compared differentiation of each ADC histogram parameter between the PCa group and BPH group,as well as between the PCa low differentiation group and moderate differentiation group.The correlation between ADC histogram parameter and 2D ADC value and 3 group was analyzed by Spearman correlation coefficient test.The ROC curve method was used to verify the diagnostic efficiency of T2WI signal,DWI signal,2D ADC value,ADC histogram parameters in PCa group and BPH group,and the diagnostic efficacy of differentiation group in PCa.ResultsThe signal performance of PCa group and BPH group in T2WI sequence was statistically different（x²=16.930,P<0.01）,and there was statistical difference in signal performance between PCa group and BPH group on DWI（x²=22.529,P<0.01）.2D ADC PCa group and BPH group were（×10-3mm²/s）（40.404±0.106 VS0.573±0.149）with statistical difference（P<0.01）;2D ADC differentiation group PCa low differentiation group and PCa（0.338±0.088 VS 0.447±0.095）with statistical difference（P<0.01）.In patients with PCa and BPH groups,the 3D ADC value histogram parameters ADCmedian（0.408±0.113 VS 0.566±0.152）,ADCmean（0.400±0.105 VS 0.561±0.154）,ADC10th（0.194±0.112 VS 0.389±0.169）,ADC25th（0.295±0.107 VS 0.471±0.162）,ADC50th（0.408±0.113 VS 0.565±0.152）,ADC75th（0.510±0.113 VS 0.654±0.150）and ADC90th（0.594±0.109 VS0.730±0.150）are statistically different（P<0.01）,Skewness and kurtosis values were not statistically significant differences（P>0.05）.In patients with PCa low differentiation group and moderate differentiation group,the 3D ADC value histogram parameters ADCmedian（0.345±0.121 VS 0.449±0.087）,ADCmean（0.339±0.100 VS 0.441±0.089）,ADC10th（0.122±0.072 VS 0.240±0.111）,ADC25th（0.231±0.088 VS 0.336±0.098）,ADC50th（0.344±0.121 VS 0.449±0.087）,ADC75th（0.449±0.124 VS 0.550±0.087）and ADC90th（0.536±0.122 VS0.632±0.083）are statistically different（P<0.05）,Skewness and kurtosis values were not statistically significant differences（P>0.05）.3D ADC histogram parameters ADCmedian,ADCmean,ADC10th,ADC25th,ADC50th,ADC75th,ADC90th and2D ADC value showed a significant negative correlation with benign and malignant degree in 3 group patients（P<0.01）,with ADC10th the most significant level（r=-0.635）.The T2WI of PCa and BPH of AUC was 0.680,the sensitivity and specificity of diagnosis were 69.70%and 66.6%,the AUC of DWI was 0.770,and the sensitivity and specificity of diagnosis were 69.70%and 84.85%respectively.2D ADC value in differential diagnosis of PCa and BPH groups,as well as PCa low differentiation group and moderate differentiation group,have efficiency,the AUC were 0.813 and 0.796 respectively.ADCmean,ADCmedian,ADC10th,ADC25th,ADC50th,ADC75th,ADC90th in differential diagnosis of PCa and BPH groups have better efficiency,ADC10th diagnostic performance best,its AUC to 0.836,the optimal cut-off value of 0.271×10^-3mm²/s,the diagnostic sensitivity and specificity were 78.79%and 84.85%.ADCmean,ADCmedian,ADC10th,ADC25th,ADC50th,ADC75th and ADC90th on the differentiation of PCa low differentiation group and moderate differentiation group have certain value,ADC10th diagnostic performance best,its AUC is 0.808,the optimal cut-off value of 0.219×10^-3mm²/s,the diagnostic sensitivity and specificity were 100%and 55%.Conclusion1.The routine T2WI sequences and DWI sequences showed statistical difference in the identification of PCa and BPH（P<0.01）,but their sensitivity needed to be improved（all 69.7%）;both of them to the PCa Gleason classification diagnosis of limited value.2.3D ADC histogram each percentile parameters and 2D ADC value on the identification of PCa and BPH,Gleason score of PCa has better diagnostic value,they are negative correlation with benign and malignant prostatic diseases（P<0.01）,the ADC10th parameters correlation is the highest,the correlation coefficient of r=-0.638.