The CT Appearances Of Renal Cystic Mass And Clinical Manifestations Of Bosniak Classification

PurposeThis study retrospectively analyzed the CT features of cystic renal masss(CRM)and evaluated the diagnostic value of the Bosniak category system for CRM.Materials and methodsThis a retrospective study of 158 patients of General Hospital of Tianjin Medical University,diagnosed with cystic renal lesions between 2014.01.01 and 2017.09.30.All patients underwent enhancement CT examination and surgery.All the renal cystic lesions(CRM)which confirmed by surgery and pathology retrospectively and independently were assessed by a junior and a senior doctor,and the imaging features of the CT finding were recorded.The imaging features included the maximum diameter of the lesion,the site,and the average CT values,multilocular or not,the thickness of the wall,calcification,separation,mural nodules,and the enhancement of mural nodules.After imaging features were recorded,the lesions were evaluated with the Bosniak category and compared with pathological results.Result1.Of all 160 renal cystic lesions(CRM),28 lesions showed calcification,of which 25 lesions were confirmed as benign by pathology,only 3 lesions were malignant,the specificity is 82.0%,and the sensitivity is 14.3%;21 lesions showed thickened wall,of which 16 cases were confirmed as malignant,the specificity is 96.4%,and the sensitivity is 74.2%;31 lesions had septa,14 cases with thickening of septa,of which 11 lesions were malignant,the specificity is 97.8%,and the sensitivity is 52.4%;16 lesions showed mural nodules,of which 14 lesions were malignant,the specificity is 98.6%,and the sensitivity is 66.7%.2.The malignant rate of categoryⅠand categoryⅡlesions in junior and senior doctor groups was 0%,the malignant rate of category ⅡF in junior and senior doctor groups was 60% and 12.5%,the malignant rate of category Ⅲ in junior and senior doctor groups was 62.5% and 63.6%,the malignant rate of category Ⅳ in junior and senior doctor groups was 87.5 and 100%.Fisher-test was used to test the malignant rate among junior and senior doctor groups.CategoryⅠand categoryⅡlesions in junior and senior doctor groups has the malignant rate;the malignant rate of category ⅡF in junior doctor group was higher than in senior doctor group,P>0.05;the malignant rate of category Ⅲ in junior doctor group was lower than in senior doctor group,P>0.05;the malignant rate of category Ⅳ in junior doctor group was lower than in senior doctor group,P>0.05.3.The area under the ROC curves in junior and senior doctor groups were 0.985(P<0.001)and 0.988(P<0.001).Mann-Whitney U test was used to test the difference of diagnostic efficiency between junior and senior doctor groups,P=0.317,showed that was no statistical difference between the two groups.Kappa test was used to test consistency between junior and senior doctor groups,a Kappa value was 0.612,indicating that there were moderate agreement of this two groups,P<0.001.Conclusion1.Calcification in a cystic renal mass is not as important in diagnosis as is the presence of associated thickening of the wall and the septa,the appearance of mural nodules and enhancing soft-tissue elements.2.There was no statistical difference between the malignant rates of each category lesions in junior and senior doctor groups.The results show that Bosniak classification system has good stability and objectivity in the detection of malignant renal cystic lesions.3.Junior and senior doctor assess renal cystic lesions(CRM)with Bosniak classification system,both of the two have high diagnostic efficiency,and there was no statistical difference between diagnostic efficacy.The Bosniak category between junior and senior doctors showed moderate agreement.So,the Bosniak classification system is a simple,comprehensible,standardized guide for diagnosis and clinical treatment,which can obviously eliminate the influence of the subjective factors such as the clinical working time and experience of the doctor.