The Comparative Imaging Study Of Cystic Renal Masses

第一部分The diagnostic value of the imaging features (US, CEUS, CT, MRI) of cystic renal massesOBJECTIVE:To evaluate the diagnostic performance of the imaging features (US, CEUS, CT, MRI) of cystic renal mass for the discrimination of benign and malignant lesions.MATERIALS AND METHODS:One hundred and three patients (77men,26 women; age range,21-83years; mean age,49.5years) with 119 cystic renal masses were included in this prospective study. The thickness of the wall and septa of the masses on US (ultrasonography, US) (n=119), CEUS (contrast enhanced ultrasonography) (n=119), CT (n=65) and MRI(n=71) were measured. The imaging features, including thick wall (>2mm), thick septa (>2mm), solid component, poly-capsular space (≧5), enhanced wall, enhanced septa and enhanced solid component, were recorded. All the masses were finally divided into benign and malignant groups according to the result of histology (n=63) and follow-up (n=56). The imaging features between benign and malignant groups were compared, the diagnostic value of these features for malignant lesions was evaluated, respectively.RESULT:The wall thickness of benign (n=55) and malignant (n=64) cystic renal masses on US were 0.34(0.18)cm vs 0.47(0.30)cm (P<0.001), on CEUS were 0.22(0.10)cm vs 0.43(0.27)cm (P<0.001), on CT were 0.27 (0.13)cm vs 0.31(0.25)cm (P>0.05), on MRI were 0.27(0.17)cm vs 0.40(0.15)cm (P<0.05). The septa thickness of benign and malignant masses on US were 0.19(0.24)cm vs 0.42(0.31)cm (P<0.001), on CEUS were 0.12(0.12)cm vs 0.36(0.25)cm (P<0.001), on CT were 0.13(0.20)cm vs 0.34(0.35)cm (P<0.05), on MRI were 0.15(0.14)cm vs 0.33(0.22)cm (P<0.05). On US, CEUS, CT and MRI, there were more malignant masses with thick septa, solid component, poly-capsular space, enhanced septa and enhanced solid component than benign ones (P<0.05). On CEUS and MRI, there were no significant differences between the number of masses with enhanced wall in malignant and benign groups (P>0.05). On US and CT, there were no significant differences between the number of masses with thick wall in malignant and benign groups (P>0.05). For the diagnosis of malignant lesion, the sensitivity, specificity and accuracy of thick wall on US were 94.55%,9.38%,48.74%, on CEUS were 90.91%, 34.38%,60.50%, on CT were 72.73%,21.88%,47.69%, and on MRI were 94.44%, 22.86%,59.15%, respectively; the sensitivity, specificity and accuracy of thick septa on US were 78.18%,57.81%,67.23%, on CEUS were 78.18%,76.56%,77.31%, on CT were 63.64%,75.00%,69.23%, and on MRI were 77.78%,65.71%,71.83%, respectively; the sensitivity, specificity and accuracy of solid component on US were 67.27%,76.56%, 72.27%, on CT were 54.55%,87.50%,70.77%, on MRI were 58.33%,74.29%,66.20% respectively; the sensitivity, specificity and accuracy of poly-capsular space on US were 58.18%,75.00%,67.22%, on CEUS were 67.27%,79.69%,73.95%, on CT were 54.55%, 90.61%,72.31%, and on MRI were 72.22%,62.86%,67.61%, respectively; the sensitivity, specificity and accuracy of enhanced wall on CEUS were 96.36%,1.56%, 45.37%, on CT were 81.82%,56.25%,69.23%, and on MRI were 91.67%,20.00%, 56.34%, respectively; the sensitivity, specificity, accuracy of enhanced septa on CEUS were 90.91%,23.44%,54.62%, on CT were 66.67%,81.25%.70.77%, and on MRI were 75.00%,71.43%,73.24%, respectively; the sensitivity, specificity, accuracy of enhanced solid component on CEUS were 67.27%,79.69%,73.95%, on CT were 51.52%,87.50%, 69.23%, and on MRI were 55.56%,85.71%,70.42%, respectively.CONCULSION:For the diagnosis of malignant cystic renal masses, on US, CEUS, CT and MRI, poly-capsular space, thick septa, solid component, and enhanced solid component show good diagnostic value, thick wall and enhanced wall show high sensitivity but low specificity; on CT and MRI, enhanced septa shows good diagnostic value; on CEUS, enhanced speta shows high sensitivity but low specificity. The thickness of the speta of most malignant masses are>2mm while most benign masses are≦2mm. 第二部分The comparison of the diagnostic ability of US, CEUS, CECT and CEMRI for the discrimination of benign and malignant cystic renal massesOBJECTIVE:To compare the diagnostic ability of US (ultrasonography), CEUS (contrast enhanced ultrasonography), CECT (contrast enhanced computed tomography), and CEMRI (contrast enhanced magnetic resonance imaging) for the discrimination of benign and malignant cystic renal masses by using the Bosniak classification system.MATERIALS AND METHODS:One hundred and three patients (77men,26 women; age range,21-83years; mean age,49.5years) with 119 cystic renal masses were included in this prospectively study. One hundred and ninteen masses underwent both US and CEUS examination,65 masses underwent both CEUS and CECT examination,71 masses underwent both CEUS and CEMRI examination, and 37 masses underwent CEUS, CECT and CEMRI examination. US, CEUS, CECT, and CEMRI image were interpreted respectively by two radiologists with more than 10 years experience in oncologic imaging, the masses were diagnosed as benign or malignant by using the Bosniak classification system (benign, categoryⅡandⅡf; malignant, categoryⅢandⅣ). The agreement of US, CEUS, CECT and CEMRI result with final diagnosis (according to histology, n=63; according to follow-up, n=56) was compared, and their diagnostic ability were evaluated.RESULT:For the diagnosis of malignant lesion, the sensitivity, specificity, accuracy of CEUS and US (n=119) were 98.18% vs 92.73%,81.25% vs 37.50% and 89.08 vs 63.03%, respectively. The area of CEUS and US under ROC were 0.897 vs 0.651. The agreement for CEUS with final diagnosis was excellent (κ=0.7883), for US was poor (κ=0.2890). For the diagnosis of malignant lesion, the sensitivity, specificity, accuracy of CEUS and CECT (n=65) were 96.97% vs 63.64%,75.00% vs 81.25%,86.15 vs 73.21% respectively. The area of CEUS and CECT under ROC were 0.829 vs 0.724. The agreement for CEUS with final diagnosis was fair to good (κ=0.7221), for CECT was also fair to good (κ=0.4476). For the diagnosis of malignant lesion, the sensitivity, specificity, accuracy of CEUS and CEMRI (n=71) were 97.22% vs 80.56%,71.43% vs 77.14%,84.51 vs 78.87%, respectively. The area of CEUS and CEMRI under ROC were 0.843 vs 0.788. The agreement for CEUS with final diagnosis was fair to good (κ=0.6980), for CEMRI was also fair to good (κ=0.5772). For the diagnosis of malignant lesion, the sensitivity, specificity, accuracy of CEUS, CECT and CEMRI (n=37) were 94.74% vs 47.37% vs 68.42%,66.67% vs 77.78% vs 77.78%,81.08% vs 62.12% vs 72.97%. The area of CEUS, CECT and CEMRI under ROC were 0.807 vs 0.626 vs 0.731. The agreement for CEUS with final diagnosis was fair to good (κ=0.6186), for CECT was poor (κ=0.2493), and for CEMRI was fair to good (κ=0.4606).CONCLUSION:For the diagnosis of malignant cystic renal masses, US is not a reliable method, CEUS has better diagnostic ability than CECT and CEMRI (bigger area under ROC, better agreement with final diagnosis, higher sensitivity and accuracy), CEMRI has better diagnostic ability than CECT. Both CECT and CEMRI have higher specificity than CEUS.