ABSTRACT
Objective To summarize the experience of using CT and MRI to diagnose the renal collecting duct carcinoma.Methods From February 2005 to January 2012,10 cases with renal collecting duct carcinoma,confirmed by pathology,were reviewed retrospectively.The data contained 6 men and 4 women,whose age ranged from 21 to 62 years (mean age 48 years).The flank pain was complained by 7 cases,waist discomfort was complained by 3 cases.In urine laboratory test,positive urine erythrocytes (++++) were found in 6 cases.In 10 cases,7 cases accepted CT examination and 3 cases accepted MRI examination.The growth pattern,lesion location,dynamic enhanced scan phase of the tumor and the way of spreading and metastasis were analyzed based on those CT and MRI images.Results The lesions were located in the left kidney in 6 cases,located in the right kidney in 4 cases.The size of tumors ranged from 4.4 cm×5.8 cm to 7.2 cm× 7.4 cm (mean size 5.7 cm× 6.4 cm).The mass,located in the center of renal parenchyma with irregular shape,showed infiltrative growth pattern.The shape of kidney was normal,whereas the border line between cortex and medulla was indistinct.The tumor involved the renal cortex and medulla in 4cases and involved the renal cortex,medulla,pelvis simultaneously in 6 cases.Among 7 patients who accepted the CT scanning,the solid mass was revealed in 6 cases.On CT plain scanning,the masses demonstrated slightly low or equal density within flaky or patchy low-density necrosis.Two cases showed small punctate calcification within the mass.One case was solid and cystic mass,which the cystic part of the mass showed irregular shape of the liquid-density.Among 3 patients accepted MRI scanning,all masses showed solid characters.The substantial part showed slightly hypointense on T1WI and low signal intensity on T2WI.The necrotic foci demonstrated low signal intensity on T1WI and high signal on T2WI.Dynamic enhanced scan revealed mild to moderate enhanced in the substantive part.The density of signal was lower than the renal cortex and slightly higher than the renal medulla in corticomedullary phase.It enhanced continuously in parenchymal phase,but still lower than the renal parenchyma.It enhanced continuously in the delayed phase,while the cystic or necrotic lesions were not observed the enhancement.Renal artery was surrounded by the mass in 2 cases.Tumor embolus was found in the renal vein in 2 cases,9 cases were noticed with renal hilum and paraortic hyperlymphonodus.The thoracic and lumbar spinal metastasis was found in 1 case and adrenal metastasis was found in another case.All patients underwent radical nephrectomy,that pathological diagnosis was renal collecting duct carcinoma.Conclusions The CT and MRI imaging characteristics of renal collecting duct carcinoma can be described as the mass located in the center of renal parenchyma with the infiltrative growth pattern.In MRI image,it demonstrates low signal intensity on T2WI.And a mild continuously enhanced can be observed on dynamic enhanced scanning.Moreover,the tumor often involves renal hilum,perirenal fat capsule,paraortic lymph node,and shows the tendency of distant metastasis.
ABSTRACT
Objective To discuss the diagnostic value of CT scan in kidney lymphoma. Methods Review the CT findings of 14 cases with kidney lymphoma proved by pathology.Eight cases were male and the other 6 cases were female,the average age was 52-year-old.Nine cases showed abdominal discomfort,2 cases showed abdominal pain,3 cases showed diarrhea,2 cases were accompanied with hematuria and 2 cases were with fever.Using Somatom Plus4 spiral CT and 4-slice Presto multi-slice spiral CT,plain scan and enhanced scan were carried out in 12 cases,arterial phase scan plus parenchymal phase scan were carried out in 2 cases.The direct and indirect signs were analyzed.Results The CT performance of 14 cases.Direct sign: Single node was in 1 case,which manifested uniform density on plain scanning and uniformly on contrast,the border was clear.Multiple nodes were in 6 cases,which presented clear border and lightly enhanced.the kidney's shape had no significantly outer convex.Diffusely invading tumor were in 7 cases,which had the finding of enlarged kidney,lightly enhanced lesions and ambiguous border.Indirect sign:the lymphoma nodes beside abdominal aortor and renal hilus enlaged were in 13 cases,in which the lymphoma nodes enlarged like array were in 4 cases,the lymphoma nodes swelled and fused,enveloped vessels,showed"abdominal aortic submerged sign"were in 3 cases.The lymphoma nodes swelled with uniform and lightly enahanted density were in 13 cases,in which the lymphoma nodes had clear border were in 9 cases.accompanied with sacral vertebra,sacral lymphoma was in 1 case,with perinephrium invasion were in 2 cases.The right kidney Surgically resected was 1 case,biopsy confirmed were 13 cases,pathology reports were all B-cell non-Hodgkin lymphoma. Conclusion For diagnosis of kidney lymphoma,the indirect typical signs have great importance besides direct important signs