Abstract
Background
Renal cysts are common incidental findings in computed tomography (CT) of the abdomen and range from benign to cystic renal cell carcinoma (RCC). Cystic RCC has various pathology, clinical prognosis, and treatment options.
Objectives
To compare preoperative CT of cystic RCC with histopathology.
Methods
Preoperative CT of histopathologically proven cystic RCCs were retrospectively reviewed in this single-center cross-sectional observational study. Two investigators recorded consensus CT features for each cystic RCC. The means of descriptive continuous data were calculated. A chi-square test, Fisher’s exact test, or an ANOVA were used for compare the frequency of findings for each histopathological subtype.
Results
Of 38 cystic RCCs, 25 were clear cell RCC, 5 were papillary RCC, 4 were multilocular cystic RCC, 1 was chromophobe RCC, and 3 were mixed type/other type (papillary/chromophobe, clear cell/chromophobe, and sarcomatoid type). We classified 36 lesions as Bosniak category IV and 2 lesions as Bosniak category III. There was no significant difference in cyst attenuation in any phase. Solid attenuation of the tumors was significantly different for each type in corticomedullary and nephrogenic phases (P = 0.001 and 0.042, respectively). Clear cell RCC was enhanced the most on corticomedullary and nephrogenic phases (means 135.5 and 112.1 Hounsfield Units, respectively). Septal thickening, enhancement, and multilocularity were significantly different between subtypes, particularly in multilocular cystic RCCs (P = 0.018, 0.018, and 0.02, respectively).
Conclusion
Preoperative CT findings may help clinicians and radiologists to predict tumor subtypes and aid treatment planning.