肾嗜酸细胞腺瘤的MDCT诊断

Diagnosis of Renal Oncocytoma by MDCT

目的：探讨肾嗜酸细胞腺瘤的MDCT诊断价值。方法：回顾性分析经病理证实的6例肾嗜酸细胞腺瘤的影像学表现，与病理资料对照并总结其特征。结果：6例均为单发肿瘤，其中左侧4例，右侧2例；直径2．1～11．8cm，平均直径6．1cm；CT平扫6例肿瘤密度均高于肾实质，钙化2例，包绕脂肪密度1例，3例可见包膜形成，出现中心放射样瘢痕3例；增强扫描皮质期强化高于髓质期4例，髓质期强化高于皮质期2例；6例病灶中1例出现节段样增强反转，3例表现为由周边向中心推进的渐进性强化，2例均匀强化，3例中央瘢痕均未见强化。结论：肾嗜酸细胞腺瘤有一定的CT表现特征，平扫稍高于肾实质的边界清楚的肿块，中心放射状瘢痕的出现及明显的渐进性强化有助于肾嗜酸细胞腺瘤的诊断，最终确诊需依赖于病理及免疫组化。

Purpose： To explore the value of multi-detector computed tomography （MDCT） in diagnosis of renal oncocytoma. Methods： Six cases of renal oncocytomas confirmed by pathology were enrolled in our study. The characteristics of these renal oncocytomas were summarized, their imaging findings were retrospectively analyzed. Results： All these 6 cases were with solitary tumor, 4 of them were on the left side, 2 on the right side; the size of these tumors ranged from 2.1 tol 1.8 cm （mean 6.1 cm）; the CT density of these tumors was all higher than that of renal parenchyma. Of all 6 tumors, 2 were with calcification, 1 with fat density, 2 with envelope, and 3 with central radial scar. On post-contrasted scan, the tumor was enhanced in cortex phase more heavily than that in parenchyma phase in 4 cases, enhanced in parenchyma phase more heavily than that in cortex phase in 2 cases; 1 case appeared as segmental enhancement, 3 cases were with progressive enhancement from peripheral to the center, 2 cases were with homogeneous enhancement, 3 cases with central scar were not enhanced. Conclusion： Renal oncocytoma has certain CT features. The density of the tumor is slightly higher than that of renal parenchyma. Central radial scar and progressive enhancement is helpful to diagnose renal oncocytoma. The final diagnosis depends on pathological and immunohistochemical exam results.