RESUMEN
Objective To investigate the imaging characteristics of mucinous tubular and spindle cell carcinoma of the kindey (MTSCC-K).Methods Five cases of pathologically confirmed MTSCC-K were analyzed retrospectively.All patients underwent CT scanning,and 4 cases underwent conventional MR and diffusion weighted imaging (DWI) scanning.MR enhancement ratio for the tumor was calculated according to MR signal intensity of pre-and post-contrast in tumor and apparent diffusion coefficient (ADC) values of tumor and normal renal cortical.Results Two case located in the right kindey,and 3 cases located in the left kindey.The maximum diameter of lesions ranged from 3.2 cm to 7.1 cm.Five cases showed nearly round shape with clear borderline.Pseudocapsule was found in 4 cases,3 cases had necrosis and cystic,and 1 case had calcification.There were no hemorrhage,fat and invasion of adjacent tissue.Isodensity or hypodense tumors were found on plain CT.Isointense or hyperintense tumors were found on plain T1WI,while isointense or mixed-signal tumors were found on plain T2WI.Slightly homogeneous or heterogeneous enhancement was observed on dynamic enhanced CT or MR,and the solid component of tumors showed hyperintense on DWI and hypointense on ADC.The mean CT value of tumor at the plain,cortical and nephrographic phase was 32.6 HU,46.5 HU and 66.5 HU,respectively.The mean ADC value of tumor and normal renal cortical was 1.23 × 10-3 mm2/s and 2.31 × 10-3 mm2/s,respectively.The mean MR percentage of enhancement value of tumor was 32.7% and 104.9%,respectively.Conclusions The imaging characteristics of MTSCC-K include nearly round shape,pseudocapsule,clear borderline,necrosis,cystic and calcification.There is no invasion of adjacent tissue and seldom malignant appearances.Isodensity or hypodense can be observed on plain CT,isointense or hyperintense on plain T1WI,and a mild continuously enhancement on dynamic enhanced scanning.
RESUMEN
Objective To evaluate the correlation of ADC values on 3.0 T MR with the pathological grades in pT1b clear cell renal cell carcinoma(CCRCC).Methods Conventional MR images,ADC values and Fuhrman pathological grading of pT1b CCRCC were performed in 30 patients.Grade Ⅰ and Ⅱ were defined as low-grade group; grade Ⅲ and IV were defined as high-grade group.The differences of ADC values among four different pathologic grades were compared with a one-way analysis of variance. The comparison of ADC values of two different grade groups was performed with t test,and the ROC curve was performed to evaluate the diagnostic efficacy of ADC value. Correlation between pathological gradings and ADC values was assessed with Spearman rank correlation analysis. Results ( 1 ) The mean ADC value of grading Ⅰ ( 10 patients ), Ⅱ ( 8 patients ),Ⅲ ( 7 patients ),IV ( 5 patients ) was ( 0.94 ± 0.11 ) ×10-3 mm2/s,(0.82 ±0.13) × 10-3 mm2/s,(0.68 ±0.09) × 10-3 mm2/s,(0.59 ±0.03) × 10-3 mm2/s,respectively.Significant differences of ADC values among the four grades were present (F =16.422,P =0.000 ).( 2 ) The mean ADC value of the low-grade group was significantly higher than that of the high-grade group(t =5.738,P =0.000).Sensitivity and specificity of diagnosing the low-grade group was 88.9% and 83.3% respectively.There was a negative correlation between pathological grading and ADC value ( r =-0.807,P < 0.05). Conclusions The ADC values of pT1b CCRCC have close correlation with pathological gradings.They can be used to predict the degree of tumor malignancy preoperatively and guide surgical planning.