Differences in Contrast-Enhanced CT Features Between Clear Cell Renal Carcinoma and Non- Clear Cell Renal Carcinoma
Purpose: Different RCC has different behavioral characteristics and their management protocol also different. Our purpose was to differentiate clear cell renal carcinoma from Non clear cell renal carcinoma with the help of contrast enhanced CT imaging features, which might help the clinician to make early decision about the management of renal cell carcinoma. Materials and methods: We retrospectively analyzed 64 patients (39 clear cell and 25 non clear cell) of renal cell carcinoma (RCC) from February, 2014 to February, 2016. We excluded 2 cases of angiomyolipoma and one case of oncocytoma because of their benign characteristics. So, total number of non- clear cell renal carcinoma was 22. Two radiologists retrospectively reviewed CT studies in an independent and blinded fashion. We compared Patient age and sex; tumor size; margin(clear or ill defined); location; presence or absence of hemorrhage, necrosis, calcification; degree of enhancement (hypodense, isodense or hyperdense) ; pattern of enhancement(homogenous or heterogeneous);tumor spreading pattern including presence or absence of thrombus (inferior vena cava and renal vein), lymphadenopathy, ascites. We performed statistical analysis with the help of SPSS 17.1 Software. Results: In corticomedullary phase, most of Clear cell RCC 21 of39 (53.8%) tended to show hyperdense enhancement, whereas, most of non- clear 21 of 22(95%) showed hypodensity and only 1 of 22(5%) showed isodensity. When, we compared homogeneity and heterogeneity in between two groups, we found non- clear RCCs(86%) were more heterogeneous than clear cell RCCS (53%)(P <0.05). ccRCC 15 of 39 (38.5%) usually located in middle pole whereas most of non- clear cell RCC 15 of 22 (68.2%) did not show any specific polarity predilection( P<0.05).33 of 39(84.6%) ccRCC involved medulla, whereas 20 of 22 (90.9%) non clear cell RCC showed mixed involvement of cortex, medulla and pelvis but no specific tendency to locate(P <0.05). Calcification was more commo
