MDCT and dual-energy CT findings of chromophobe renal cell carcinoma / 实用放射学杂志

ABSTRACT

Objective To investigate the MDCT and dual-energy CT (DECT)features of chromophobe renal cell carcinoma (chRCC)and to improve the diagnostic accuracy before operation.Methods The data of MDCT(46 cases of 47 lesions)and DECT (10 cases )of 56 patients with pathologically confirmed 57 chRCC were retrospectively analyzed.All of them underwent plain scan-ning,corticomedullary phase and parenchymal phase scanning after contrast material injection.The lesions were divided into ≤4 cm group and > 4 cm group according to its maximum diameter.Qualitative and quantitative analysis were compared between the groups.Results 64.9% of chRCCs were round and oval,87.7% of chRCCs were solid or mainly solid tumors.The incidence of hemorrhage,necrosis,calcification,cystic degeneration of the tumors was approximately 38.6%,36.8%,10.5% and 12.3%,respec-tively.Central scar(1 7.5%)and vascular sign (24.6% )were seen in part of chRCCs.The tumors showed iso and high attenuation on plain CT scanning in 47.4% and 45.6% of the lesions,respectively.The enhancement pattern of wash-in and wash-out,prolonged enhancement and delayed enhancement were seen in approximately 24.6%,66.7% and 8.8% of the lesions,respectively.The shape, necrosis and cystic degeneration,vascular sign and density uniformity between the two groups were statistically different.The CT value of the lesions were 37.29 HU,82.58 HU and 78.97 HU on unenhanced,corticomedullary phase and parenchymal phase CT scanning.The lesion-kidney ratio on the three phases was 1.29,0.62 and 0.55,respectively.There was no significant difference be-tween CT values and LKR values.The lesions and its subtle signs were much clearer on the 80 kV images of DECT after contrast in-jection.Conclusion The MDCT and DECT findings of chRCC have certain characteristics.However,when the lesions showed atypi-cal CT findings because of its different degree of enhancement and variable enhancement pattern,it would be very difficult to get an accurate diagnosis and the final results depend on pathological diagnosis.