Department of Urology, University of Miami-Miller School of Medicine, PO Box 016960 (M-814), Miami, FL 33101, USA.
World J Urol. 2011 Dec;29(6):787-92. doi: 10.1007/s00345-010-0586-7. Epub 2010 Aug 18.
We investigate the use of 4-phase computerized tomography with intravenous contrast to help distinguish oncocytoma from renal cell carcinoma (RCC) in tumors <4 cm.
We retrospectively identified patients who underwent surgical management for renal tumors <4 cm from 2005 to 2008. Patients who had pre-operative CT evaluation as per our institution's renal mass protocol and had confirmed pathological diagnosis of either oncocytoma or RCC were included in the study. Enhancement readings were obtained for the tumor and the renal cortex using the same slice simultaneously.
Our cohort involved 69 patients (46 men, 23 women; mean age 66) who presented with 79 renal masses. Histopathologically 40 were clear cell, 22 papillary, 5 chromophobe RCC and 12 oncocytoma. On the arterial, venous and delayed phase images, oncocytoma showed the highest mean enhancement change, i.e.,546, 396 and 239% followed by clear cell RCC 261, 261 and 174%, chromophobe RCC 147, 127 and 66% and papillary RCC 137, 184 and 118%, respectively. The enhancement pattern differed significantly on comparing oncocytoma with RCC (P < 0.007). The mean percentage contrast excreted at the end of the delayed phase was 33.3, 13.8, 32 and 53% for clear cell, papillary, chromophobe and oncocytoma, respectively.
The enhancement and washout values in Hounsfield units obtained by multiphasic CT scan aid in distinguishing oncocytoma from the commonly seen subtypes of RCC in renal masses <4 cm. This preliminary study demonstrates that arterial phase enhancement greater than 500% and washout values of greater than 50% are exclusively seen in renal oncocytomas.
我们研究了使用 4 期计算机断层扫描（CT）加静脉对比剂，以帮助区分<4cm 的肿瘤中的嗜酸细胞瘤与肾细胞癌（RCC）。
我们回顾性地确定了 2005 年至 2008 年期间因肾肿瘤<4cm 而接受手术治疗的患者。这些患者的术前 CT 评估符合我们机构的肾肿瘤方案，并经病理诊断证实为嗜酸细胞瘤或 RCC。在同一切片上同时获得肿瘤和肾皮质的增强读数。
我们的队列包括 69 名患者（46 名男性，23 名女性；平均年龄 66 岁），他们共出现 79 个肾脏肿块。组织病理学上，40 个为透明细胞，22 个为乳头状，5 个为嫌色细胞，12 个为嗜酸细胞瘤。在动脉期、静脉期和延迟期图像上，嗜酸细胞瘤的平均增强变化最高，分别为 546%、396%和 239%，其次是透明细胞 RCC 261%、261%和 174%，嫌色细胞 RCC 147%、127%和 66%，乳头状 RCC 137%、184%和 118%。比较嗜酸细胞瘤与 RCC 的增强模式差异有统计学意义（P<0.007）。在延迟期结束时，平均排出的百分比分别为透明细胞、乳头状、嫌色细胞和嗜酸细胞瘤的 33.3%、13.8%、32%和 53%。
多期 CT 扫描获得的 Hounsfield 单位的增强和洗脱值有助于区分<4cm 的肿瘤中的嗜酸细胞瘤与常见的 RCC 亚型。这项初步研究表明，动脉期增强>500%和洗脱值>50%仅见于肾嗜酸细胞瘤。
