肾嗜酸细胞腺瘤与透明细胞癌的多期螺旋CT增强特征对比研究

Characteristic finding of renal oncocytoma and clear-cell renal cell carcinoma with multiphase CT

目的 探讨肾嗜酸细胞腺瘤（RO）与透明细胞癌（ccRCC）（直径≤5 cm）在肾脏4期CT增强扫描中的强化特征.方法 回顾性分析11例经手术病理证实的RO与45例ccRCC的多期CT增强扫描图像.56例肿瘤在皮髓期均表现为非均质性强化,将肿瘤内实性成分分成高、低强化区两部分,分别测量肿瘤内高、低强化区及正常肾皮质在4期扫描中的CT值并采用x2检验和MannWhitney检验进行比较.结果 皮髓期RO内高强化区CT值的中位数（四分位距）为163.0 HU（ 141.0 ～ 178.0 HU）,低于ccRCC的CT值194.0 HU（166.5 ～235.0 HU）,差异有统计学意义（Z=-2.847,P=0.004）.分泌期与皮髓期相比,RO内原高强化区的CT值降低70.0 HU（41.0～86.0 HU）,低于透明细胞癌的CT差值87.0 HU （65.0 ～1 26.5 HU）,差异有统计学意义（Z= -2.032,P =0.042）.在11例嗜酸细胞腺瘤中,皮髓期显示为低强化的区域在分泌期CT值有所增加者有9例；在45例透明细胞癌中CT值增加者共21例,两者差异有统计学意义（x2=4.391,P=0.036）.分泌期,嗜酸细胞腺瘤内高低强化区CT差值9.0 HU（6.0～ 15.0 HU）,低于透明细胞癌16.0 HU（11.0～31.5 HU）,差异有统计学意义（Z=-2.622,P=0.009）.结论 皮髓期RO内高血供区强化程度低于ccRCC.分泌期,RO内原高强化区的对比剂退出程度不及ccRCC,原低强化区的CT值在此期多有进一步的提高,此时病变内部的密度较ccRCC更为均匀.

Objective To evaluate characteristic imaging findings of tumor attenuation in 4-phase CT between renal oncocytoma （ RO ） and clear-cell renal ceil carcinoma （ ccRCC ） of small tumor size （≤Scm）.Methods Fifty-six patients with histologically confirmed renal masses （11 ROs and 45 ccRCCs） were included in this study.Heterogeneous enhancement was found all tumors during the corticomedullary phase （CMP）.The CT values of the normal renal cortex,the relatively high enhanced region and the relatively less-enhanced region of the tumor were measured in each phase.Statistical comparison was carried out by Chi-square test or Mann-Whitney test.Results In CMP,the CT value of the relatively high enhanced region in RO [ 163.0 HU （ 141.0—178.0 HU） ] was significantly lower than that in ccRCC [ 194.0 HU （ 166.5—235.0 HU） ; Z = -2.847,P =0.004].Compared CMP with the excretory phase,the attenuation of the relatively highly enhanced region in RO [70.0 HU （41.0—86.0 HU）] were significantly lower than that in ccRCC [87.0 HU （65.0—126.5 HU） ] （Z= -2.032,P =0.042）.In the excretory phase,9 of 11 ROs had a further enhancement with its relatively less-enhanced region which was significantly higher than that in ccRCC （21/45 ; x2 = 4.391,P = 0.036）.Conclusions In CMP,the CT value of the relatively high enhanced region in RO was significantly lower than that in ccRCC.Compared with ccRCC,in the excretory phase,the RO had less attenuation of the relatively highly enhanced region with homogeneous density.